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Sample records for equipment review mechanical

  1. Lifetime of Mechanical Equipment

    Energy Technology Data Exchange (ETDEWEB)

    Leland, K.

    1999-07-01

    The gas plant at Kaarstoe was built as part of the Statpipe gas transport system and went on stream in 1985. In 1993 another line was routed from the Sleipner field to carry condensate, and the plant was extended accordingly. Today heavy additional supply- and export lines are under construction, and the plant is extended more than ever. The main role of the factory is to separate the raw gas into commercial products and to pump or ship it to the markets. The site covers a large number of well-known mechanical equipment. This presentation deals with piping, mechanical and structural disciplines. The lifetime of mechanical equipment is often difficult to predict as it depends on many factors, and the subject is complex. Mechanical equipment has been kept in-house, which provides detailed knowledge of the stages from a new to a 14 years old plant. The production regularity has always been very high, as required. The standard of the equipment is well kept, support systems are efficient, and human improvisation is extremely valuable.

  2. Mechanical (turbines and auxiliary equipment)

    CERN Document Server

    Sherry, A; Cruddace, AE

    2013-01-01

    Modern Power Station Practice, Volume 3: Mechanical (Turbines and Auxiliary Equipment) focuses on the development of turbines and auxiliary equipment used in power stations in Great Britain. Topics covered include thermodynamics and steam turbine theory; turbine auxiliary systems such as lubrication systems, feed water heating systems, and the condenser and cooling water plants. Miscellaneous station services, and pipework in power plants are also described. This book is comprised of five chapters and begins with an overview of thermodynamics and steam turbine theory, paying particular attenti

  3. Estimation of the cost of electro-mechanical equipment for small hydropower plants – review and comparison of methods

    Directory of Open Access Journals (Sweden)

    Lipiński Seweryn

    2017-01-01

    Full Text Available The estimate of the cost of electro-mechanical equipment for new small hydropower plants most often amounts to about 30-40% of the total budget. In case of modernization of existing installations, this estimation represents the main cost. This matter constitutes a research problem for at least few decades. Many models have been developed for that purpose. The aim of our work was to collect and analyse formulas that allow estimation of the cost of investment in electro-mechanical equipment for small hydropower plants. Over a dozen functions were analysed. To achieve the aim of our work, these functions were converted into the form allowing their comparison. Then the costs were simulated with respect to plants’ powers and net heads; such approach is novel and allows deeper discussion of the problem, as well as drawing broader conclusions. The following conclusions can be drawn: significant differences in results obtained by using various formulas were observed; there is a need for a wide study based on national investments in small hydropower plants that would allow to develop equations based on local data; the obtained formulas would let to determinate the costs of modernization or a new construction of small hydropower plant more precisely; special attention should be payed to formulas considering turbine type.

  4. Mechanical equipment for magnet measurement and alignment

    International Nuclear Information System (INIS)

    Harvey, A.

    1992-05-01

    The mechanical equipment for measuring and aligning (or fiducializing) magnets is described by reference to devices designed and built by a number of laboratories. Some of these are now available commercially. The descriptions are supplemented by a list of representative sources of hardware

  5. 29 CFR 1926.952 - Mechanical equipment.

    Science.gov (United States)

    2010-07-01

    ... equipment that are not covered with insulating protective equipment. (c) Derrick trucks, cranes and other lifting equipment. (1) All derrick trucks, cranes and other lifting equipment shall comply with subpart N...

  6. 21 CFR 211.68 - Automatic, mechanical, and electronic equipment.

    Science.gov (United States)

    2010-04-01

    ... SERVICES (CONTINUED) DRUGS: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR FINISHED PHARMACEUTICALS Equipment § 211.68 Automatic, mechanical, and electronic equipment. (a) Automatic, mechanical, or electronic... 21 Food and Drugs 4 2010-04-01 2010-04-01 false Automatic, mechanical, and electronic equipment...

  7. Review of equipment aging theory and technology. Final report

    International Nuclear Information System (INIS)

    Carfagno, S.P.; Gibson, R.J.

    1980-09-01

    The theory and technology of equipment aging is reviewed, particularly as they relate to the qualification of safety-system equipment for nuclear power generating stations. A fundamental degradation model is developed, and its relation to more restricted models (e.g., Arrhenius and inverse-stress models) is shown. The most common theoretical and empirical models of aging are introduced, and limitations on their practical application are analyzed. Reliability theory and its application to the acceleration of aging are also discussed. A compendium of aging data for materials and components, including degradation mechanisms, failure modes and activation energies, is included

  8. Review of equipment aging theory and technology. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Carfagno, S.P.; Gibson, R.J.

    1980-09-01

    The theory and technology of equipment aging is reviewed, particularly as they relate to the qualification of safety-system equipment for nuclear power generating stations. A fundamental degradation model is developed, and its relation to more restricted models (e.g., Arrhenius and inverse-stress models) is shown. The most common theoretical and empirical models of aging are introduced, and limitations on their practical application are analyzed. Reliability theory and its application to the acceleration of aging are also discussed. A compendium of aging data for materials and components, including degradation mechanisms, failure modes and activation energies, is included.

  9. Discussion on the safety classification of nuclear safety mechanical equipment

    International Nuclear Information System (INIS)

    Shen Wei

    2010-01-01

    The purpose and definition of the equipment safety classification in nuclear plant are introduced. The differences of several safety classification criterions are compared, and the object of safety classification is determined. According to the regulation, the definition and category of the safety functions are represented. The safety classification method, safety classification process, safety class interface, and the requirement for the safety class mechanical equipment are explored. At last, the relation of the safety classification between the mechanical and electrical equipment is presented, and the relation of the safety classification between mechanical equipment and system is also presented. (author)

  10. Environmental/dynamic mechanical equipment qualification and dynamic electrical equipment qualification program (EDQP)

    International Nuclear Information System (INIS)

    Hunter, J.A.

    1984-01-01

    Equipment qualification research is being conducted to investigate acceptable criteria, requirements, and methodologies for the dynamic (including seismic) and environmental qualification of mechanical equipment and for the dynamic (including seismic) qualification of electrical equipment. The program is organized into three elements: (1) General Research, (2) Environmental Research, and (3) Dynamic Research. This paper presents the highlights of the results to date in these three elements of the program

  11. Plutonium Immobilization Can Loading Equipment Review

    International Nuclear Information System (INIS)

    Kriikku, E.; Ward, C.; Stokes, M.; Randall, B.; Steed, J.; Jones, R.; Hamilton, L.

    1998-05-01

    This report lists the operations required to complete the Can Loading steps on the Pu Immobilization Plant Flow Sheets and evaluates the equipment options to complete each operation. This report recommends the most appropriate equipment to support Plutonium Immobilization Can Loading operations

  12. Design review report for modifications to RMCS safety class equipment

    International Nuclear Information System (INIS)

    Corbett, J.E.

    1997-01-01

    This report documents the completion of the formal design review for modifications to the Rotary Mode Core Sampling (RMCS) safety class equipment. These modifications are intended to support core sampling operations in waste tanks requiring flammable gas controls. The objective of this review was to approve the Engineering Change Notices affecting safety class equipment used in the RMCS system. The conclusion reached by the review committee was that these changes are acceptable

  13. Design review report for modifications to RMCS safety class equipment

    Energy Technology Data Exchange (ETDEWEB)

    Corbett, J.E.

    1997-05-30

    This report documents the completion of the formal design review for modifications to the Rotary Mode Core Sampling (RMCS) safety class equipment. These modifications are intended to support core sampling operations in waste tanks requiring flammable gas controls. The objective of this review was to approve the Engineering Change Notices affecting safety class equipment used in the RMCS system. The conclusion reached by the review committee was that these changes are acceptable.

  14. Collaboration Mechanism for Equipment Instruction of Multiple Energy Systems

    Science.gov (United States)

    Wang, Dong; Wang, Tuo; Wang, Qi; Zhang, Zhao; Zhao, Mingyu; Wang, Yinghui

    2018-01-01

    When multiple energy systems execute optimization instructions simultaneously, and the same equipment is Shared, the instruction conflict may occur. Aiming at the above problems, taking into account the control objectives of each system, the characteristics of different systems, such as comprehensive clean energy, energy efficiency, and peak filling, etc., designed the instruction coordination mechanism for the daemon. This mechanism mainly acts on the main station of the system, and form a final optimization instruction. For some specific scenarios, the collaboration mechanism of unlocking the terminal is supplemented. The mechanism determines the specific execution instructions based on the arrival time of the instruction. Finally, the experiment in Tianjin eco-city shows that this algorithm can meet the instruction and collaboration requirements of multi-energy systems, and ensure the safe operation of the equipment.

  15. PRECISION MOTION SYSTEM FOR OPTO-MECHANICAL EQUIPMENT OF MICROELECTRONICS

    Directory of Open Access Journals (Sweden)

    I. V. Dainiak

    2015-01-01

    Full Text Available The paper proposes a structure of precision motion system built on the basis of a circular multi-coordinate synchronous segment motor and reconfigurable parallel kinematic mechanism. The multi-coordinate synchronous segment motor may have from two to six movable segments depending on the design, and number of the segments generally defines an internal mobility of the motor. A specific feature of the parallel kinematic mechanism consists in the possibility of its structure reconfiguration by serial connection of two neighboring rods with the help of free elements of their spherical joints into triangular circuits with one spherical hinge at the common vertex. As result of this, the controlled motion of motor movable segments is transformed into the complex spatial displacement of circular platform with number of degrees of freedom up to six inclusively.A mathematical model for solution of the kinematic problem in the investigated parallel mechanism has been offered in the paper. The model allows to calculate a position of movable segments of multi-coordinate synchronous motor depending on the desired position and orientation of the executive circular platform. The parametric definition of base point positions in the motor segments in time allows eventually to form algorithms of programmable motions.The paper substantiates ability to embed the developed motion system into projection unit of opto-mechanical equipment while preserving traditional configuration scheme. This provides the possibility of adaptive adjustment of optical elements during operation; it allows to adjust the optical elements when the geometry of projection system is changed due to deterioration. As result, main characteristics of projection system: resolution, depth of field and image contrast and distortion are maintained at the required level. The developed motion system can be used as a coordinate system of positioning, alignment and scanning in the assembly and other

  16. Cleaning and sterilisation of infant feeding equipment: a systematic review.

    Science.gov (United States)

    Renfrew, Mary J; McLoughlin, Marie; McFadden, Alison

    2008-11-01

    To assess the clinical and cost-effectiveness of different methods of cleaning and sterilisation of infant feeding equipment used in the home. Systematic review of studies from developed countries on the effectiveness of methods of cleaning and sterilisation of infant feeding equipment used in the home. A brief telephone survey of UK-based manufacturers of infant feeding equipment and formula to ascertain the evidence base used for their recommendations, and a comparison of current relevant guidelines in developed countries, informed the work. National guidelines from six countries demonstrated variation and lack of evidence to support current guidance. Manufacturers did not report evidence of effectiveness to support their recommendations. Nine studies were identified; eight conducted between 1962 and 1985 and one in 1997. All had methodological weaknesses. Hand-washing was identified as fundamentally important. Health professionals were reported as not providing appropriate education on the importance and methods of cleaning and sterilisation. Mothers of subsequent babies and women from lower socio-economic groups were less likely to follow recommended procedures. There is a lack of good-quality evidence on effective ways of cleaning and sterilising infant feeding equipment in the home. The evidence base does not answer the question about which of the methods in common use is most effective or most likely to be used by parents. Hand-washing before handling feeding equipment remains important. Further research on the range of methods used in the home environment, including assessment of the views of parents and carers, is required.

  17. Harvest of table olives by mechanical harvesting equipment

    Directory of Open Access Journals (Sweden)

    Filippo Gambella

    2013-09-01

    Full Text Available In this work, we have evaluated the performance, of an electric comb equipped with five undulated fingers used for mechanized the harvesting of table olives. The first aim of the work was to test three different types of coating materials used for covering the fingers: Silicon (S, Vulcanized rubber (VR and Natural rubber (NR. The diameter of the coating materials tested were 7mm (D1, 14 mm (D2, 19 mm (D3 in order to evaluate the damage of different working conditions on the intact olives. During harvesting, silicon at 7mm and 14mm resulted in the largest percentage of undamaged the fruit (67% and 65%, natural rubber 63% and vulcanized rubber at the 54%. The second aim was to evaluate the combination, in terms of the best performance, of the machines used for mechanized harvesting of table olives. Several factors have been examined: undulating fingers variation thickness, different rotational speeds and different coating materials used to reduce the impact damage on olives. From the tests on olive tree we have determined that while plastic materials (S and (NR appear to have a positive role in harvest quality, the vibration transmitted to the operator’s hand is great from 6.48 m/s2 for S to 6.31 m/ s2 for NR and 2.92 m/s2 for VR, respect to the materials used.

  18. 49 CFR 176.905 - Motor vehicles or mechanical equipment powered by internal combustion engines.

    Science.gov (United States)

    2010-10-01

    ... of ignition. A motor vehicle or mechanical equipment showing any signs of leakage or electrical fault... equipment is stowed. (f) Each hold or compartment must be ventilated and fitted with an overhead water... smoke or fire detection system capable of alerting personnel on the bridge. (h) All electrical equipment...

  19. Technology review of commercial food service equipment - final report

    Energy Technology Data Exchange (ETDEWEB)

    Rahbar, S; Krsikapa, S [Canadian Gas Research Inst., Don Mills, ON (Canada); Fisher, D; Nickel, J; Ardley, S; Zabrowski, D [Fisher Consultants (Canada); Barker, R F [ed.

    1996-05-15

    Market and technical information on gas fired equipment used in the commercial food service sector in Canada and in each province or territory was presented. Results of a market study and technology review were integrated to establish energy consumption and energy saving potential in this sector. Eight categories of commercial cooking appliances were studied. They were: fryers, griddles, broilers, ranges, ovens, tilting skillets, steam kettles and steamers. Focus was on gas fired appliances, although electric appliances were also included. The total energy consumption of the appliances was estimated at 76,140.37 GBtu in 1994. Gas appliances accounted for 63 per cent of the total inventory and consumed 83 per cent of the total energy used. Cooking energy efficiencies for the gas fired commercial cooking equipment ranged from 10 per cent to 60 per cent. The electric appliances had cooking energy efficiencies ranging from 35 per cent to 95 per cent. A list of recommendations were made for the many opportunities to introduce higher efficiency commercial cooking appliances, essential to slow down or to stabilize the energy consumption of cooking appliances over the next decade. 66 refs., 14 tabs., 18 figs.

  20. A REVIEW ON TEXTILES IN SPACE PROTECTION EQUIPMENTS

    Directory of Open Access Journals (Sweden)

    SUNTER EROGLU Nilsen

    2017-05-01

    Full Text Available Astronauts need the lander for decelerate and bridle the speed when they land on the space surface slowly. This lander could be controlled velocity magnitude in any direction or orientation and provide protection. The landers consist of airbags and parachutes. The airbag is a type of vehicle safety device, have a soft cushioning and is an occupant restraint system. The parachute provides to slow the motion of an object through an atmosphere by the hauling. Space protection equipments must have some properties because of astronaut’s entry, descend and landing in safely. Textiles in airbags provide these properties especially which are light weight, low gas permeability, high strength, low cost, low temperature flexibility and low coefficient of friction. For textiles in parachutes must have properties such as smooth, porosity, air permeability, high strength, cost-effective, stability light weight and good in drag and lift. Airbags and parachutes in space protection equipment’s are improved in systems provide easy stability. Recently, inflatable technologies for space protection equipments plays a fundamental role in building re-entry capsule. It can be performed a variety of pre-flight analyses to ensure the success of the tests of protection systems from day to day. In this review, space protection systems, their textile materials and properties, their advantages and disadvantages are presented.

  1. 49 CFR 173.220 - Internal combustion engines, self-propelled vehicles, mechanical equipment containing internal...

    Science.gov (United States)

    2010-10-01

    ... and vehicles with certain electronic equipment when transported by aircraft or vessel. When an... vehicles, mechanical equipment containing internal combustion engines, and battery powered vehicles or... Than Class 1 and Class 7 § 173.220 Internal combustion engines, self-propelled vehicles, mechanical...

  2. Preventing infection from reusable medical equipment: a systematic review

    Directory of Open Access Journals (Sweden)

    Hart Tony

    2002-03-01

    Full Text Available Abstract Background In 2000, the World Health Organization (WHO had eight sets of conflicting recommendations for decontaminating medical equipment. We conducted a systematic review of observational studies to assist WHO in reconciling the various guidelines. This paper summarises the methods developed and illustrates the results for three procedures – alcohol, bleach and povidone iodine. Methods We developed a Medline search strategy and applied inclusion criteria specifying the decontamination procedures of interest and an outcome of microbial destruction for a set of marker organisms. We developed protocols to assess the quality of studies and categorised them according to the reliability of the methods used. Through an iterative process we identified best practice for the decontamination methods and key additional factors required to ensure their effectiveness. We identified 88 published papers for inclusion, describing 135 separate studies of decontamination. Results For disinfection with alcohol, best practice was identified from 23 studies as an exposure to 70–80% ethanol or isopropanol for at least 5 minutes. Bleach was effective for sterilization at a concentration of 5000 ppm for 5 minutes and for disinfection at 1000 ppm for 10 minutes (33 studies. Povidone iodine was only partially effective for disinfection at a concentration of 1% for 15 minutes (15 studies. Conclusions Our findings provide an evidence base for WHO guidelines on decontaminating medical equipment. The results support the recommended use of bleach and show that alcohol could be used more widely than current guidelines suggest, provided best practice is followed. The effectiveness of povidone iodine is uncertain.

  3. Limited usage of mechanical equipment in small-scale rice farming: a cause for concern

    Directory of Open Access Journals (Sweden)

    Gaudiose Mujawamariya

    2017-06-01

    Full Text Available The role of mechanization in agriculture is well documented in terms of improving productivity of farm labour and land and sustaining income status and welfare of small-scale farmers. In rice production, there is a high cost associated with labour intensive production practices especially in land preparation, weeding and harvesting, the limited adoption of mechanical equipment in these operations remains an issue of concern. The current study investigates the usage of mechanical equipment in a setting where majority of farmers are exposed to technologies but cases of non-usage/adoption are observed. The choice of usage of mechanical equipment is analysed through probit and poisson models. Mechanization generally has a positive effect on production. However, the cost associated with its usage high. The equipment should be made available and affordable to farmers especially because demand for rent is not met. Awareness is essential for adoption and ease of use of mechanization.

  4. Survey on requirements for independent reviews and inspections of electrical and I and C equipment

    International Nuclear Information System (INIS)

    Byman, Karin; Groenkvist, Stefan; Egerbo, Anders; Nilsson, Thomas

    2009-03-01

    In this survey, licensing procedures for the implementation of different kinds of components and systems in nuclear power plants have been studied in four European countries: Belgium (Finland), Germany, and Switzerland. The main focus has been to describe the general features of the licensing procedures for electrical and for instrumentation and control (IandC) equipment and systems. The regulatory framework for the operation of nuclear power plants in Belgium is based on the American regulations. The licensing procedure for each modification of significance for the safety of a plant is carried out by the authorised inspection organisation (AVN), which follows its own procedures for the review of the modification file, the commissioning, and conformity check of the installation. These procedures are very general and independent of the technical domain of the equipment or system and AVN uses the US regulations standard review plan (SRP) as a reference for technical reviews. The Federal Agency for Nuclear Control (FANC) is responsible for the surveillance of all nuclear activities in Belgium, but the private non-profit authorised inspection organisation (AVN) does perform inspections and other regulatory tasks delegated by FANC. Controls of electrical components and systems with regard to the general Belgian electrical regulations are performed by accredited inspection organisations. The regulatory framework for the safety of nuclear activities in Finland is domestic and detailed safety requirements are provided by the Radiation and Nuclear Safety Authority (STUK). They cover specific requirements for the licensing procedure for electrical and IandC equipment. In Finland, there are no general differences in the licensing procedure for electrical, instrumentation, and mechanical equipment and the licensing procedure is basically the same for all types of systems, structures and equipment. STUK has the responsibility for the regulatory control in Finland and may seek

  5. Flow measurement in mechanical ventilation: a review.

    Science.gov (United States)

    Schena, Emiliano; Massaroni, Carlo; Saccomandi, Paola; Cecchini, Stefano

    2015-03-01

    Accurate monitoring of flow rate and volume exchanges is essential to minimize ventilator-induced lung injury. Mechanical ventilators employ flowmeters to estimate the amount of gases delivered to patients and use the flow signal as a feedback to adjust the desired amount of gas to be delivered. Since flowmeters play a crucial role in this field, they are required to fulfill strict criteria in terms of dynamic and static characteristics. Therefore, mechanical ventilators are equipped with only the following kinds of flowmeters: linear pneumotachographs, fixed and variable orifice meters, hot wire anemometers, and ultrasonic flowmeters. This paper provides an overview of these sensors. Their working principles are described together with their relevant advantages and disadvantages. Furthermore, the most promising emerging approaches for flowmeters design (i.e., fiber optic technology and three dimensional micro-fabrication) are briefly reviewed showing their potential for this application. Copyright © 2015 IPEM. Published by Elsevier Ltd. All rights reserved.

  6. Mechanical engineering department technical review

    International Nuclear Information System (INIS)

    Carr, R.B.; Denney, R.M.

    1981-01-01

    The Mechanical Engineering Department Technical Review is published to: (1) inform the readers of various technical activities within the department, (2) promote exchange of ideas, and (3) give credit to the personnel who are achieving the results. The report is formatted into two parts: technical acievements and publication abstracts. The first is divided into eight sections, one for each division in the department providing the reader with the names of the personnel and the division accomplishing the work

  7. Mechanical Engineering Department. Technical review

    Energy Technology Data Exchange (ETDEWEB)

    Simecka, W.B.; Condouris, R.A.; Talaber, C. (eds.)

    1980-01-01

    The Mechanical Engineering Department Technical Review is published to (1) inform the readers of various technical activities within the Department, (2) promote exchange of ideas, and (3) give credit to the personnel who are achieving the results. The report is formatted into two parts: technical achievements and publication abstracts. The first is divided into eight sections, one for each Division in the Department providing the reader with the names of the personnel and the Division accomplishing the work.

  8. Mechanical Engineering Department Technical Review

    International Nuclear Information System (INIS)

    Carr, R.B.; Denney, R.M.

    1981-01-01

    The Mechanical Engineering Department Technical Review is published to inform readers of various technical activities within the Department, promote exchange of ideas, and give credit to personnel who are achieving the results. The report is presented in two parts: technical achievements and publication abstracts. The first is divided into seven sections, each of which reports on an engineering division and its specific activities related to nuclear tests, nuclear explosives, weapons, energy systems, engineering sciences, magnetic fusion, and materials fabrication

  9. Mechanical Engineering Department. Technical review

    International Nuclear Information System (INIS)

    Simecka, W.B.; Condouris, R.A.; Talaber, C.

    1980-01-01

    The Mechanical Engineering Department Technical Review is published to (1) inform the readers of various technical activities within the Department, (2) promote exchange of ideas, and (3) give credit to the personnel who are achieving the results. The report is formatted into two parts: technical achievements and publication abstracts. The first is divided into eight sections, one for each Division in the Department providing the reader with the names of the personnel and the Division accomplishing the work

  10. Equipment monitoring and diagnosis of their mechanical condition

    International Nuclear Information System (INIS)

    Morel, J.; Monnier, B.

    1994-01-01

    The main objectives of reactor monitoring are reviewed and the three monitoring types are described: reception controls and alarms, periodical controls, and specific monitoring. The monitoring process is then presented: information acquisition, dysfunction detection and diagnosis, risk analysis and maintenance action determination. Diagnosis assistance is now automated with expert systems such as DIVA (shaft vibration diagnosis) and DIAPO (primary pump diagnosis). Several application examples at EDF are described: SEXTEN reactor containment tightness monitoring, large and small-size turbo-machine monitoring, reactor inner structure monitoring, loose part detection in the primary circuit. All these informations will be centralized in a general monitoring and diagnosis assistance station. 3 fig

  11. Research on the energy and ecological efficiency of mechanical equipment remanufacturing systems

    Science.gov (United States)

    Shi, Junli; Cheng, Jinshi; Ma, Qinyi; Wang, Yajun

    2017-08-01

    According to the characteristics of mechanical equipment remanufacturing system, the dynamic performance of energy consumption and emission is explored, the equipment energy efficiency and emission analysis model is established firstly, and then energy and ecological efficiency analysis method of the remanufacturing system is put forward, at last, the energy and ecological efficiency of WD615.87 automotive diesel engine remanufacturing system as an example is analyzed, the way of energy efficiency improvementnt and environmental friendly mechanism of remanufacturing process is put forward.

  12. Versatile equipment for mechanical testing of active materials

    International Nuclear Information System (INIS)

    Bertsch, Johannes; Heimgartner, Peter

    2005-01-01

    At the Paul Scherrer Institute (PSI) 3 different project groups presently perform aging research on active materials. The research fields are fusion, high neutron flux targets and LWR relevant components. Up to now mechanical testing has been performed with small, low dose rate samples behind local shielding, not appropriate for highly activated material. To overcome this situation, a cell concept for active mechanical testing was elaborated and has been erected in PSI's Hotlab. It consists of 4 shielded cells. 3 connected cells are versatile and independently operable for highly beta/gamma active samples. One cell is an alpha/beta/gamma-box which will be realized in a second phase. This paper presents the versatility especially of the beta/gamma-cells: The different user groups perform experiments in these cells, whereas different machines can be placed into the cells. As consequence of the need of heavily shielded cell doors, a special strengthening and levelling of the floor has been required. In all cells the relevant media are installed. Besides the performance of the cells, the project progress as the difficulties and their solutions are described. (Author)

  13. Technology review of commercial food service equipment - final report

    Energy Technology Data Exchange (ETDEWEB)

    Rahbar, S; Krsikapa, S [Canadian Gas Research Inst., Don Mills, ON (Canada); Fisher, D; Nickel, J; Ardley, S; Zabrowski, D [Fisher Consultants (Canada); Barker, R F [ed.

    1996-05-15

    Technical information on commercial gas cooking appliances was presented. This second volume provided an appliance-by-appliance comprehensive assessment of the energy performance of commercial food service equipment. Energy assessments were made for the following categories of cooking equipment: fryers, griddles, broilers, ranges, Chinese ranges, ovens, steamers, steam kettles, and braising pans. Recommendations were made for improving the energy efficiency and overall performance of gas appliances to support of the Canadian gas utilities marketing and energy conservation initiatives. 71 refs., 37 tabs., 58 figs.

  14. Design/Operations review of core sampling trucks and associated equipment

    International Nuclear Information System (INIS)

    Shrivastava, H.P.

    1996-01-01

    A systematic review of the design and operations of the core sampling trucks was commissioned by Characterization Equipment Engineering of the Westinghouse Hanford Company in October 1995. The review team reviewed the design documents, specifications, operating procedure, training manuals and safety analysis reports. The review process, findings and corrective actions are summarized in this supporting document

  15. Teacher-Perceived Adequacy of Tools and Equipment Available to Teach Agricultural Mechanics

    Science.gov (United States)

    McCubbins, O. P.; Anderson, Ryan G.; Paulsen, Thomas H.; Wells, Trent

    2016-01-01

    Agricultural mechanics is an important component of a well-rounded school-based agricultural education (SBAE) program. Within agricultural mechanics courses lies a plethora of topics and skills to be covered. Adequate tools and equipment are vital in preparing students to fill an expanding, 21st century workforce. The issue of inadequate teaching…

  16. Survey on requirements for independent reviews and inspections of electrical and I and C equipment

    Energy Technology Data Exchange (ETDEWEB)

    Byman, Karin; Groenkvist, Stefan; Egerbo, Anders; Nilsson, Thomas (AaF Consult AB, Stockholm (Sweden))

    2009-03-15

    In this survey, licensing procedures for the implementation of different kinds of components and systems in nuclear power plants have been studied in four European countries: Belgium (Finland), Germany, and Switzerland. The main focus has been to describe the general features of the licensing procedures for electrical and for instrumentation and control (IandC) equipment and systems. The regulatory framework for the operation of nuclear power plants in Belgium is based on the American regulations. The licensing procedure for each modification of significance for the safety of a plant is carried out by the authorised inspection organisation (AVN), which follows its own procedures for the review of the modification file, the commissioning, and conformity check of the installation. These procedures are general and independent of the technical domain of the equipment or system and AVN uses the US regulations standard review plan (SRP) as a reference for technical reviews. The Federal Agency for Nuclear Control (FANC) is responsible for the surveillance of all nuclear activities in Belgium, but the private non-profit authorised inspection organisation (AVN) does perform inspections and other regulatory tasks delegated by FANC. Controls of electrical components and systems with regard to the general Belgian electrical regulations are performed by accredited inspection organisations. The regulatory framework for the safety of nuclear activities in Finland is domestic and detailed safety requirements are provided by the Radiation and Nuclear Safety Authority (STUK). They cover specific requirements for the licensing procedure for electrical and IandC equipment. In Finland, there are no general differences in the licensing procedure for electrical, instrumentation, and mechanical equipment and the licensing procedure is basically the same for all types of systems, structures and equipment. STUK has the responsibility for the regulatory control in Finland and may seek

  17. Review of Climatic Protection Techniques for Electronic Equipments.

    Science.gov (United States)

    1982-10-01

    that the water vapour to be measured is carried in a dry nitrogen gas flow to an electrolytic cell which electrolyses the water vapour to hydrogen and...environments, the major factor being protection from the effects of water and water vapour in the atmosphere aided by temperature effects. The effects of...moisture on equipments, achieving and maintaining a dry interior, sealing standards, water vapour barriers, desiccation, drying-out procedures and

  18. A Review of the Soldier’s Equipment Burden

    Science.gov (United States)

    2011-12-01

    allow heavy items to be packed close to the soldier’s natural centre of mass . The Infantryman, with such a large equipment burden, is in effect...COM Centre of Mass COTS Commercial Off-the-Shelf CPL Corporal DARPA Defense Advanced Research Project Agency DMO Defence Materiel...Eighteen soldiers had customised their packs, either the issued packs or their own. The most common customisation was the addition of an external

  19. Safety Review related to Commercial Grade Digital Equipment in Safety System

    International Nuclear Information System (INIS)

    Yu, Yeongjin; Park, Hyunshin; Yu, Yeongjin; Lee, Jaeheung

    2013-01-01

    The upgrades or replacement of I and C systems on safety system typically involve digital equipment developed in accordance with non-nuclear standards. However, the use of commercial grade digital equipment could include the vulnerability for software common-mode failure, electromagnetic interference and unanticipated problems. Although guidelines and standards for dedication methods of commercial grade digital equipment are provided, there are some difficulties to apply the methods to commercial grade digital equipment for safety system. This paper focuses on regulatory guidelines and relevant documents for commercial grade digital equipment and presents safety review experiences related to commercial grade digital equipment in safety system. This paper focuses on KINS regulatory guides and relevant documents for dedication of commercial grade digital equipment and presents safety review experiences related to commercial grade digital equipment in safety system. Dedication including critical characteristics is required to use the commercial grade digital equipment on safety system in accordance with KEPIC ENB 6370 and EPRI TR-106439. The dedication process should be controlled in a configuration management process. Appropriate methods, criteria and evaluation result should be provided to verify acceptability of the commercial digital equipment used for safety function

  20. Visualization environment for reviewing and experimenting with compaction equipment trajectories in context

    NARCIS (Netherlands)

    Vasenev, Alexandr; Hartmann, Timo; Miller, Seirgei Rosario; Doree, Andries G.

    Visualization Environments (VEs) can assist construction professionals in studying intricate interrelations between construction equipment trajectories and their context. Such VEs typically support them in either reviewing earlier conducted work or experimenting with possible alternatives. In the

  1. Review of foreign equipment for powered support control

    Energy Technology Data Exchange (ETDEWEB)

    Sikora, W; Sobczyk, J

    1986-10-01

    A new generation of control systems are comparatively evaluated developed by Dowty, Hemscheidt and Thyssen-Siemens for powered supports and shield supports. Types of functions controlled by each system are discussed: support advancing (lowering support canopy, advancing, increasing pressure), control of support position, advancing chain conveyor. The following control systems are described: fully automatic control, remote control from a gate road, manual control from an adjacent support unit. Types of electronic equipment used in the control systems are described: microcomputers (8-bit CMOS device), 8-bit microcomputers, transmission systems, measuring instruments. Advantages of control systems developed and manufactured by the 3 companies are comparatively evaluated.

  2. Safety review for seismic qualification on nuclear power plant equipment

    International Nuclear Information System (INIS)

    Fang Qingxian

    1995-01-01

    The standards and requirements for seismic qualification of nuclear power plant's component have been fully addressed, including the scope of seismic qualification, the approach and the method of common seismic qualification, the procedure of the seismic tests, and the criteria for the seismic qualification review. The problems discovered in the safety review and the solution for these problems and some other issues are also discussed

  3. 21 CFR 111.30 - What requirements apply to automated, mechanical, or electronic equipment?

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false What requirements apply to automated, mechanical, or electronic equipment? 111.30 Section 111.30 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION CURRENT GOOD MANUFACTURING...

  4. [A young child with respiratory acidosis and hypoxia from mechanical ventilation with equipment made for adults].

    Science.gov (United States)

    Joor, Fleur; Markhorst, Dick G; Kneyber, Martin C J; van Heerde, Marc

    2011-01-01

    During mechanical ventilation of young children, problems may arise due to the additional dead space of the ventilation circuit. This may lead to respiratory acidosis and even hypoxia in the child. A 3-month-old boy suffered from frequent apnoea. He was mechanically ventilated for this. Shortly after its initiation, he developed severe respiratory acidosis, hypoxemia and circulatory insufficiency. This was due to a large additional dead space caused by the use of equipment components made for adults. After he was switched to a circuit suitable for himself, he recovered rapidly. As a rule of thumb, an additional dead space of 1.5-2 ml/kg body weight is acceptable in young children. Emergency wards for young children should have specific equipment to mechanically ventilate them, and have a protocol paying explicit attention to the dead space.

  5. Review: equipment for anionic surfactant manufacture from oil palm

    Directory of Open Access Journals (Sweden)

    Jesús Alfonso Torres Ortega

    2010-05-01

    Full Text Available In the present study is performed a review of the current processes of sulfonation of various raw materials for determine the process conditions in order to present the state of the art of sulfonation processes for the manufacture of anionic surfactants. There has been a scientific literature with emphasis on several aspects: Technology, sulfonation reactors and operating conditions in the process, analytical techniques for monitoring the reaction degree, the mathematical models proposed in the literature for the sulfonation/sulfation in tubular absorbers, patenting and specialized industry publications in this area.

  6. Lunar astrobiology: a review and suggested laboratory equipment.

    Science.gov (United States)

    Gronstal, Aaron; Cockell, Charles S; Perino, Maria Antonietta; Bittner, Tobias; Clacey, Erik; Clark, Olathe; Ingold, Olivier; Alves de Oliveira, Catarina; Wathiong, Steven

    2007-10-01

    In October of 2005, the European Space Agency (ESA) and Alcatel Alenia Spazio released a "call to academia for innovative concepts and technologies for lunar exploration." In recent years, interest in lunar exploration has increased in numerous space programs around the globe, and the purpose of our study, in response to the ESA call, was to draw on the expertise of researchers and university students to examine science questions and technologies that could support human astrobiology activity on the Moon. In this mini review, we discuss astrobiology science questions of importance for a human presence on the surface of the Moon and we provide a summary of key instrumentation requirements to support a lunar astrobiology laboratory.

  7. Research program for seismic qualification of nuclear plant electrical and mechanical equipment. Task 3. Recommendations for improvement of equipment qualification methodology and criteria. Volume 3

    International Nuclear Information System (INIS)

    Kana, D.D.; Pomerening, D.J.

    1984-08-01

    The Research Program for Seismic Qualification of Nuclear Plant Electrical and Mechanical Equipment has spanned a period of three years and resulted in seven technical summary reports, each of which covered in detail the findings of different tasks and subtasks, and have been combined into five NUREG/CR volumes. Volume 3 presents recommendations for improvement of equipment qualification methodology and procedural clarification/modification. The fifth category identifies issues where adequate information does not exist to allow a recommendation to be made

  8. Research program for seismic qualification of nuclear plant electrical and mechanical equipment. Task 4. Use of fragility in seismic design of nuclear plant equipment. Volume 4

    International Nuclear Information System (INIS)

    Kana, D.D.; Pomerening, D.J.

    1984-08-01

    The Research Program for Seismic Qualification of Nuclear Plant Electrical and Mechanical Equipment has spanned a period of three years and resulted in seven technical summary reports, each of which have covered in detail the findings of different tasks and subtasks, and have been combined into five NUREG/CR volumes. Volume 4 presents study of the use of fragility concepts in the design of nuclear plant equipment and compares the results of state-of-the-art proof testing with fragility testing

  9. Management of waste electrical and electronic equipment in Romania: A mini-review.

    Science.gov (United States)

    Ciocoiu, Carmen Nadia; Colesca, Sofia Elena; Rudăreanu, Costin; Popescu, Maria-Loredana

    2016-02-01

    Around the world there are growing concerns for waste electrical and electronic equipment. This is motivated by the harmful effects of waste electrical and electronic equipment on the environment, but also by the perspectives of materials recovery. Differences between countries regarding waste electrical and electronic equipment management are notable in the European Union. Romania is among the countries that have made significant efforts to comply with European Union regulations, but failed reaching the collection target. The article presents a mini review of the waste electrical and electronic equipment management system in Romania, based on legislation and policy documents, statistical data, research studies and reports published by national and international organisations. The article debates subjects like legislative framework, the electrical and electronic equipment Romanian market, the waste electrical and electronic equipment collection system, waste electrical and electronic equipment processing and waste electrical and electronic equipment behaviour. The recast of the European directive brings new challenges to national authorities and to other stakeholders involved in the waste electrical and electronic equipment management. Considering the fact that Romania has managed a collection rate of roughly 1 kg capita(-1) in the last years, the new higher collection targets established by the waste electrical and electronic equipment Directive offer a serious challenge for the management system. Therefore, another aim of the article is to highlight the positive and negative aspects in the Romanian waste electrical and electronic equipment field, in order to identify the flows that should be corrected and the opportunities that could help improve this system to the point of meeting the European standards imposed by the European Directive. © The Author(s) 2015.

  10. Market Competitiveness Evaluation of Mechanical Equipment with a Pairwise Comparisons Hierarchical Model.

    Science.gov (United States)

    Hou, Fujun

    2016-01-01

    This paper provides a description of how market competitiveness evaluations concerning mechanical equipment can be made in the context of multi-criteria decision environments. It is assumed that, when we are evaluating the market competitiveness, there are limited number of candidates with some required qualifications, and the alternatives will be pairwise compared on a ratio scale. The qualifications are depicted as criteria in hierarchical structure. A hierarchical decision model called PCbHDM was used in this study based on an analysis of its desirable traits. Illustration and comparison shows that the PCbHDM provides a convenient and effective tool for evaluating the market competitiveness of mechanical equipment. The researchers and practitioners might use findings of this paper in application of PCbHDM.

  11. Search for the optimal size of printed circuit boards for mechanical structures for electronic equipment

    Directory of Open Access Journals (Sweden)

    Yefimenko A. A.

    2014-12-01

    Full Text Available The authors present a method, an algorithm and a program, designed to determine the optimal size of printed circuit boards (PCB of mechanical structures and different kinds of electronic equipment. The PCB filling factor is taken as an optimization criterion. The method allows one to quickly determine the dependence of the filling factor on the size of the PCB for various components.

  12. BOOK REVIEWS: Quantum Mechanics: Fundamentals

    Science.gov (United States)

    Whitaker, A.

    2004-02-01

    This review is of three books, all published by Springer, all on quantum theory at a level above introductory, but very different in content, style and intended audience. That of Gottfried and Yan is of exceptional interest, historical and otherwise. It is a second edition of Gottfried’s well-known book published by Benjamin in 1966. This was written as a text for a graduate quantum mechanics course, and has become one of the most used and respected accounts of quantum theory, at a level mathematically respectable but not rigorous. Quantum mechanics was already solidly established by 1966, but this second edition gives an indication of progress made and changes in perspective over the last thirty-five years, and also recognises the very substantial increase in knowledge of quantum theory obtained at the undergraduate level. Topics absent from the first edition but included in the second include the Feynman path integral, seen in 1966 as an imaginative but not very useful formulation of quantum theory. Feynman methods were given only a cursory mention by Gottfried. Their practical importance has now been fully recognised, and a substantial account of them is provided in the new book. Other new topics include semiclassical quantum mechanics, motion in a magnetic field, the S matrix and inelastic collisions, radiation and scattering of light, identical particle systems and the Dirac equation. A topic that was all but totally neglected in 1966, but which has flourished increasingly since, is that of the foundations of quantum theory. John Bell’s work of the mid-1960s has led to genuine theoretical and experimental achievement, which has facilitated the development of quantum optics and quantum information theory. Gottfried’s 1966 book played a modest part in this development. When Bell became increasingly irritated with the standard theoretical approach to quantum measurement, Viki Weisskopf repeatedly directed him to Gottfried’s book. Gottfried had devoted a

  13. A mechanical design for positioning of gm detector for system of avian flu virus detection equipment

    International Nuclear Information System (INIS)

    Rahmat; Budi Santoso; Krismawan; Abdul Jalil

    2010-01-01

    Mechanical design for positioning of GM detector system has been done. It is used for avian flu detection equipment. The requirements for the design are to protect detection system against shock, portable, and easy to maintain. The mechanical system consists of connectors, cable assemblies, holders, casing, housing and detectors cover. The selected material should have small gamma radiation absorption property in order to give optimum counts for the detector. The design result should give a system that is easy to operate, cheap and easy to assemble. (author)

  14. Mechanical design for positioning of GM detector for system of avian flu virus detection equipment

    International Nuclear Information System (INIS)

    Rahmat; Budi Santoso; Krismawan; Abdul Jalil

    2010-01-01

    Mechanical design for positioning of GM detector system has been done. It is used for avian flu detection equipment. The requirements for the design are to protect detection system against shock, portable, and easy to maintain. The mechanical system consists of connectors, cable assemblies, holders, casing, housing and detectors cover. The selected material should have small gamma radiation absorption property in order to give optimum counts for the detector. The design result should give a system that is easy to operate, cheap and easy to assemble. (author)

  15. Loosening and damage mechanism of thread-joined structures in nuclear power equipment

    International Nuclear Information System (INIS)

    Tang Hui

    1999-01-01

    The author proposes a loosening mechanism of thread-joined structures under vibrate environments in the nuclear power equipment and structures, which is on the base of the macro and imperceptible-mechanics analysis. It has answered the problems on the seizing, the adhesive wearing, the generation of cracks, the thread-tooth fracture. So it has a conclusion that the loosening of thread-joined structures is essential trend, in other words, the locking property of thread-pair is failure under vibrate environments

  16. Indoor pollutants emitted by office equipment: A review ofreported data and information needs

    Energy Technology Data Exchange (ETDEWEB)

    Destaillats, Hugo; Maddalena, Randy L.; Singer, Brett C.; Hodgson, Alfred T.; McKone, Thomas E.

    2007-02-01

    There is concern that potentially harmful pollutants may be emitted from office equipment. Although office equipment has been a focal point for governmental efforts to promote energy efficiency through programs such as the US EPA's Energy Star, little is known about the relationship between office equipment use and indoor air quality, and information on pollutant emissions is sparse. In this review, we summarize available information on emission rates and/or ambient concentrations of various pollutants that are related to office equipment use. Experimental methods used in the characterization of emissions are briefly described. The office equipment evaluated in this review includes computers (desktops and notebooks), printers (laser, ink-jet and all-in-one machines) and photocopy machines. Reported emission rates of the following pollutant groups are summarized: volatile organic chemicals (VOCs), ozone, particulate matter and several semivolatile organic chemicals (SVOCs). The latter include phthalate esters, brominated flame retardants, organophosphate flame retardants and polycyclic aromatic hydrocarbons (PAHs). We also review studies reporting airborne concentrations in indoor environments where office equipment was present and thought to be a significant contributor to the total pollutant burden (offices, residences, schools, electronics recycling plants). For certain pollutants, such as organophosphate flame retardants, the link between emission by office equipment and indoor air concentrations is relatively well established. However, indoor VOCs, ozone, PAHs and phthalate esters can originate from a variety of sources, and their source apportionment is less straightforward. This literature review identifies substances of toxicological significance, with the purpose of serving as a guide to evaluate their potential importance with respect to human exposures.

  17. Mechanical Engineering Department technical review

    Energy Technology Data Exchange (ETDEWEB)

    Carr, R.B.; Abrahamson, L.; Denney, R.M.; Dubois, B.E (eds.)

    1982-01-01

    Technical achievements and publication abstracts related to research in the following Divisions of Lawrence Livermore Laboratory are reported in this biannual review: Nuclear Fuel Engineering; Nuclear Explosives Engineering; Weapons Engineering; Energy Systems Engineering; Engineering Sciences; Magnetic Fusion Engineering; and Material Fabrication. (LCL)

  18. Skin mechanical properties and modeling: A review.

    Science.gov (United States)

    Joodaki, Hamed; Panzer, Matthew B

    2018-04-01

    The mechanical properties of the skin are important for various applications. Numerous tests have been conducted to characterize the mechanical behavior of this tissue, and this article presents a review on different experimental methods used. A discussion on the general mechanical behavior of the skin, including nonlinearity, viscoelasticity, anisotropy, loading history dependency, failure properties, and aging effects, is presented. Finally, commonly used constitutive models for simulating the mechanical response of skin are discussed in the context of representing the empirically observed behavior.

  19. Cost determination of the electro-mechanical equipment of a small hydro-power plant

    Energy Technology Data Exchange (ETDEWEB)

    Ogayar, B.; Vidal, P.G. [Grupo de Investigacion IDEA, Escuela Politecnica Superior, University of Jaen, Campus de Las Lagunillas, s/n. 23071-Jaen (Spain)

    2009-01-15

    One of the most important elements on the recovery of a small hydro-power plant is the electro-mechanical equipment (turbine-alternator), since the cost of the equipment means a high percentage of the total budget of the plant. The present paper intends to develop a series of equations which determine its cost from basic parameters such as power and net head. These calculations are focused at a level of previous study, so it will be necessary to carry out the engineering project and request a budget to companies specialized on the construction of electro-mechanical equipment to know its cost more accurately. Although there is a great diversity in the typology of turbines and alternators, data from manufacturers which cover all the considered range have been used. The above equations have been developed for the most common of turbines: Pelton, Francis, Kaplan and semiKaplan for a power range below 2 MW. The obtained equations have been validated with data from real installations which have been subject to analysis by engineering companies working on the assembly and design of small plants. (author)

  20. Mechanized covering application in equipment surfaces; Aplicacao mecanizada de revestimento em superficies de equipamentos

    Energy Technology Data Exchange (ETDEWEB)

    Abreu, Billy A. de; Broering, Carlos E. [Universidade Federal de Santa Catarina (UFSC), Florianopolis, SC (Brazil). Dept. de Engenharia Mecanica

    2004-07-01

    Facing such challenges, the main objective of this work is to develop automated equipment and new welding procedures to be used to repair tank reservoirs operating in corrosive media. The equipment is expected to be applied directly in the maintenance of petrochemical plants. The project consists on a mechanical displacement device, able to move along a flexible rail, which can be fixed to a concave or convex surface and fitting itself to the geometry. A transversal arm gives it a second movement ability, allowing oscillatory displacements and the exact positioning of the pistol. As it is widely known, the automated welding process results in a considerably increase in productivity and quality, when comparing to the hand made process. Therefore, knowing the parameters involved and adjusted the welding variables to the best values, it is expected to achieve welding free of imperfections, inconsistencies and errors, and able to be repetitive. (author)

  1. Mechanisms of radioprotection - a review

    International Nuclear Information System (INIS)

    Copeland, E.S.

    1978-01-01

    Theories of radiation protection can be considered at both the molecular and biochemical-physiological levels. Four molecular level protection hypotheses, radical scavenging, hydrogen transfer reactions, the mixed disulfide hypothesis and the endogenous non-protein sulfhydryl hypothesis, probably describe different aspects of the actual protection mechanism, although each has inconsistencies. At the biochemical-physiological level, hypothermia induction and biochemical shock may be involved in protection of the organism against radiation induced damage and death. It is most likely that no single mechanism can account for the protection offered by a radioprotective drug. Certain compounds may operate primarily by means of physiological effects resulting in hypoxia or hypothermia in critical tissues. Others may operate primarily by influencing the intrinsic radiosensitivity of target molecules by causing localized radical scavenging or by donating a hydrogen atom. Metabolic effects such as biochemical shock, release of endogenous non-protein sulfhydryls, induction of structural changes in target molecules or delay in DNA synthesis and cell division are also possible mechanisms for radioprotection. (author)

  2. Development of microstructure to optimise mechanical performance of power generation equipment

    International Nuclear Information System (INIS)

    Marshall, P.

    1986-11-01

    The factors responsible for the development of microstructure in CEGB construction ceramics and steels is assessed as a function of composition, thermomechanical treatment, thermal ageing and environmental degradation. The relationships between microstructure and mechanical properties (tensile, toughness, creep and fatigue) of relevance to structures operating in power generation equipment is then developed in quantitative terms. The conclusions from the assessment are as follows: 1 The relationship between microstructure and mechanical properties of construction ceramics and steels used in the power generation industry has been assessed. 2 Factors which significantly influence microstructure and thus mechanical properties are chemical composition, thermomechanical treatment, ageing and environmental degradation. The influence of such microstructural changes in tensile, toughness, fatigue and creep properties of ceramics and steels is assessed. 3 The benefits arising from an understanding of materials behaviour are discussed in terms of improved materials and the assessment of plant performance. (author)

  3. A preliminary design of mechanical device on industrial digital radiography equipment design

    International Nuclear Information System (INIS)

    Nur Khasan; Samuel Praptoyo

    2015-01-01

    A preliminary design of mechanical device on industrial digital radiography equipment has been done. this design is intended as a basis for the manufacture of complete facilities for the realization a prototype on industrial digital radiography equipment. the design and construction were carried out by paying attention to the general configuration of the basic design in which its mechanical design has several components with specific dimensions and heavy mass. this design consist of a main frame holder, flat panel detector support and hydraulic hand stacker for mounting the x-ray machine. this mechanical device design will then be fabricated to facilitate and assist work of digital radiographic retrieval. computer application programs sketch-up is used to draw this design and the analysis stress of autodesk inventor to analysis the strength construction design. the results of this design are the configuration drawing, sketch drawings of construction and the safety factor of construction design with a minimum value of 2.39 as well as a maximum value of 15 when to be simulated by the load 500 Kg which is 4 times of total workload. (author)

  4. Review of heavy ion reaction mechanisms

    International Nuclear Information System (INIS)

    Ngo, C.

    1986-04-01

    We review some of the many aspects of heavy-ion reaction mechanisms observed at bombarding energies smaller than approximately 50 MeV/u that is to say in what is called the low bombarding energy domain and the intermediate bombarding energy domain. We emphasize the results concerning the use of very heavy projectiles which has led to the observation of new mechanisms

  5. Shooting mechanisms in Nature : A systematic review

    NARCIS (Netherlands)

    Sakes, A.; van der Wiel, M.; Henselmans, P.W.J.; van Leeuwen, J.L.; Dodou, D.; Breedveld, P.

    2016-01-01

    Background
    In nature, shooting mechanisms are used for a variety of purposes, including prey capture, defense, and reproduction. This review offers insight into the working principles of shooting mechanisms in fungi, plants, and animals in the light of the specific functional demands that these

  6. Critical review of the equipment hatch of a large dry steel containment. The DEFENDER IMPROVEMENT

    International Nuclear Information System (INIS)

    Mantega, F.; Penno, E.; Vanini, P.

    1994-01-01

    Performances of the Containment System under Severe Accident conditions depend on a number of different features and components. The equipment hatch may be considered a critical component because it is a potential main contributor to the total Containment leak rate during a Severe accident and a potential (depending on the design) direct leak path between the containment atmosphere and the environment. The analytical study performed to anticipate the response of the equipment hatch of a large dry steel containment under Severe Accident condition has pointed out some questions of concern. The possible leak tightness failure mechanism are related to: the gaskets elastic characteristics degradation due to thermal and radiological aging; the deformation of the hatch sleeve induced by the containment wall; and the differential expansion between gasket material and steel. Beside, the equipment hatch may be considered a single barrier and although it is equipped with two gaskets, it is not difficult to demonstrate that a backup function cannot be assigned to the external gasket. For these reason it seems to be necessary to realize a wider application of the 'Defence in Depth' criteria in the design of this component. The DEFENDER (DEFENce in Depth Equipment hatch Requalification) might be a solution to increase the margin of safety of the equipment hatch under the Severe Accident condition. (author)

  7. Review and evaluation of technology, equipment, codes and standards for digitization of industrial radiographic film

    International Nuclear Information System (INIS)

    1992-05-01

    This reports contains a review and evaluation of the technology, equipment, and codes and standards related to the digitization of industrial radiographic film. The report presents recommendations and equipment-performance specifications that will allow the digitization of radiographic film from nuclear power plant components in order to produce faithful reproductions of flaw images of interest on the films. Justification for the specifications selected are provided. Performance demonstration tests for the digitization process are required and criteria for such tests is presented. Also several comments related to implementation of the technology are presented and discussed

  8. Equivalent mechanical parameters of oscillating rotary motors used in transport equipment

    Directory of Open Access Journals (Sweden)

    A. Andziulis

    2006-12-01

    Full Text Available In various appliances and equipment of sundry transport means there is a lot of diverse mechanisms of periodical movement. So, the various piston or membrane pumps of fuel feeding and lubrication systems, circulation pumps, air and refrigerating coolant compressors, etc. are the typical examples of innovative and well promising application of the oscillating motors. In these cases the moving part of a motor can be directly connected to the working body of driven mechanism without the additional gears. Consequently, the drive can be simplified in design and improved in efficiency and reliability. Application of the oscillating rotary motors, if used in the aforesaid devices, strictly depends on specific properties of mechanical system of a motor aggregated with the driven mechanism and considered as the one-piece unit on the whole. So, this study analyses how the properties of mechanical system, comprised of two moving parts interconnected eccentrically or centrically, can be evaluated by the equivalent rotational inertia, equivalent mass and by equivalent mechanical power factor which, in turn, determine the operating characteristics and basic possibilities of the motor.

  9. Mathematical modelling of a Fin Ray type mechanism, used in the case of the wrist rehabilitation equipment

    Directory of Open Access Journals (Sweden)

    Filip Ovidiu

    2017-01-01

    Full Text Available The paper presents the mathematical modelling of some Fin Ray-type mechanism, destined for the wrist-rehabilitation equipment, its driving being made by a pneumatic muscle. The validity of the mathematical modelling of Fin Ray mechanism is verified by threedimensional mechanism made in Pro/Engineer.

  10. SPECIFIC DEGRADATION STRUCTURE FEATURES AND MECHANICAL PROPERTIES OF FURNACE AND HEAT POWER EQUIPMENT ELEMENTS AFTER LONG-TERM OPERATION

    Directory of Open Access Journals (Sweden)

    F. I. Panteleenko

    2012-01-01

    Full Text Available The paper presents results of investigations on structure and mechanical properties of technological equipment elements made of heat-resistant steels. A scale of chrome and molybdenum steel microstructure degradation based on evaluation of  coagulated carbide size and material mechanical properties (a point from 0-operation without time limits, up to 4-operation prohibition has been proposed in the paper. It has been  established that an analysis of  steel microstructure directly on equipment elements by means of a portable microscope is an efficient express method for evaluation of equipment condition and structures due to control of material structure degradation rate of a diagnosed object.

  11. ERG review of waste package corrosion mechanisms

    International Nuclear Information System (INIS)

    Geisert, R.E.

    1988-01-01

    The Engineering Review Group (ERG) was established by the Office of Nuclear Waste Isolation (ONWI) to help evaluate engineering-related issues in the US Department of Energy's nuclear waste repository program. The ERG reviewed the waste package corrosion mechanisms. This report documents the ERG's comments and recommendations on these subjects and the ONWI response to the specific points raised by the ERG. 1 ref

  12. A Materials and Equipment Review of Selected U.S. Geothermal District Heating Systems

    Energy Technology Data Exchange (ETDEWEB)

    Rafferty, K D [P.E.

    0000-12-30

    Geothermal district heating systems are now quite common in the western U.S. A recent survey identified a total of 17 such systems. The performance of materials and equipment in 13 of these systems is reviewed in this paper. Specific areas covered include: production facilities, central plants, distribution, customer connection, metering and disposal. Those areas: characterized by the highest incidence of problems include: production well pumps, customer branch piping and energy metering.

  13. Automation and mechanization of in-service inspection of selected equipment in FRG's nuclear power plants

    International Nuclear Information System (INIS)

    Metke, E.

    1988-01-01

    The procedures and equipment are described for the automation and mechanization of in-service inspection in nuclear power plants in the FRG, used by the KWU company. Checks of the pressure vessel are done by visual means using a colour tv camera, the method of eddy currents and the ultrasonic method. An analysis is made of the time schedule of ultrasonic inspections, and the central column manipulator is described which allows to check all internal regions of the pressure vessel. Attention is also devoted to other devices, e.g., those for prestressing shanks, cleaning shanks, cleaning thread apertures, etc. A combined probe using the ultrasonic method and the eddy current method serves the inspection of heat exchange tubes in the steam generator. For inspecting the primary circuit the KWU company uses devices for checking and working the inner surface of pipes. Briefly described are examples of using KWU equipment in nuclear power plants in CMEA countries. (Z.M.). 11 figs., 6 refs

  14. An Expert System for Supporting the Design and Selection of Mechanical Equipment for Recreational Crafts

    Directory of Open Access Journals (Sweden)

    T. Gonciarz

    2014-06-01

    Full Text Available Expert Systems can be defined as computer programs, whose main task is to simulate a human expert, usually in a narrow field of expertise. Expert Systems have experienced tremendous growth and popularity since their commercial introduction in the early 1970’s. Today, Expert Systems are used in business, science, engineering, manufacturing and other engineering applications such as planning, scheduling, diagnosing equipment failures and are used in almost every stage of the manufacturing process and also in medicine and many other fields. Expert Systems belong to the field of artificial intelligence. An intelligent computer program that uses knowledge and inference procedures to solve problems that are difficult enough to require significant human expertise for the solution. The purpose of this paper is to present an Expert System which assists with the design of yachts and supports the selection of mechanical equipment for yachts and includes knowledge in the field of yachting engineering. Using the presented Expert System reduces the time during the design and production preparation process.

  15. Designing electronic equipment on the basis of standard mechanical structures using internet re­sour­ces

    Directory of Open Access Journals (Sweden)

    Karlangach A. P.

    2016-12-01

    Full Text Available The author proposes a method to design electronic equipment based on functional-node design method that involves the use of 2D- and 3D- models mechanical structures for electronic equipment as a way to reduce development time and errors when creating design documentation for electronic equipment. At present, most areas of science and technology are computerized, more problems in designing electronic equipment are dealt with using computer-aided design (CAD and Computer-aided manufacturing (CAM to reduce the time required for development and manufacturing of electronic equipment. Development of design documentation also requires a more effective approach, because the less the time for development of the design documentation is, the faster the developed device will go into production. The aim of the study is to develop a method of designing electronic equipment using 2D and 3D models of standard mechanical structures for electronic equipment using Internet resources. Based on the presented methods is an example of designing a device from standard bearing structures. Compared with traditional technology, the method of designing electronic equipment using standard parts has the following advantages: - reduces time and improves quality of development through the use of existing design documentation; - accelerates the implementation and introducing into production processes; - increases unification of design solutions.

  16. Mechanisms of beryl flotation: a literature review

    International Nuclear Information System (INIS)

    Torem, M.L.

    1988-01-01

    This paper shows a review about the investigations that have been done on the mechanisms of flotation of beryl and its dependence in relation to the presence of fluoride species. It is also analised the anionic flotation of the mineral and the effect of cations in the pulp of flotation. (author) [pt

  17. Osteoarthritis year in review 2015: mechanics.

    Science.gov (United States)

    Varady, N H; Grodzinsky, A J

    2016-01-01

    Motivated by the conceptual framework of multi-scale biomechanics, this narrative review highlights recent major advances with a focus on gait and joint kinematics, then tissue-level mechanics, cell mechanics and mechanotransduction, matrix mechanics, and finally the nanoscale mechanics of matrix macromolecules. A literature review was conducted from January 2014 to April 2015 using PubMed to identify major developments in mechanics related to osteoarthritis (OA). Studies of knee adduction, flexion, rotation, and contact mechanics have extended our understanding of medial compartment loading. In turn, advances in measurement methodologies have shown how injuries to both the meniscus and ligaments, together, can alter joint kinematics. At the tissue scale, novel findings have emerged regarding the mechanics of the meniscus as well as cartilage superficial zone. Moving to the cell level, poroelastic and poro-viscoelastic mechanisms underlying chondrocyte deformation have been reported, along with the response to osmotic stress. Further developments have emerged on the role of calcium signaling in chondrocyte mechanobiology, including exciting findings on the function of mechanically activated cation channels newly found to be expressed in chondrocytes. Finally, AFM-based nano-rheology systems have enabled studies of thin murine tissues and brush layers of matrix molecules over a wide range of loading rates including high rates corresponding to impact injury. With OA acknowledged to be a disease of the joint as an organ, understanding mechanical behavior at each length scale helps to elucidate the connections between cell biology, matrix biochemistry and tissue structure/function that may play a role in the pathomechanics of OA. Copyright © 2015 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  18. Osteoarthritis Year in Review 2015: Mechanics

    Science.gov (United States)

    Varady, Nathan H.; Grodzinsky, Alan J.

    2015-01-01

    Motivated by the conceptual framework of multi-scale biomechanics, this narrative review highlights recent major advances with a focus on gait and joint kinematics, then tissue-level mechanics, cell mechanics and mechanotransduction, matrix mechanics, and finally the nanoscale mechanics of matrix macromolecules. A literature review was conducted from January 2014 to April 2015 using PubMed to identify major developments in mechanics related to osteoarthritis (OA). Studies of knee adduction, flexion, rotation, and contact mechanics have extended our understanding of medial compartment loading. In turn, advances in measurement methodologies have shown how injuries to both the meniscus and ligaments, together, can alter joint kinematics. At the tissue scale, novel findings have emerged regarding the mechanics of the meniscus as well as cartilage superficial zone. Moving to the cell level, poroelastic and poroviscoelastic mechanisms underlying chondrocyte deformation have been reported, along with the response to osmotic stress. Further developments have emerged on the role of calcium signaling in chondrocyte mechanobiology, including exciting findings on the function of mechanically activated cation channels newly found to be expressed in chondrocytes. Finally, AFM-based nano-rheology systems have enabled studies of thin murine tissues and brush layers of matrix molecules over a wide range of loading rates including high rates corresponding to impact injury. With OA acknowledged to be a disease of the joint as an organ, understanding mechanical behavior at each length scale helps to elucidate the connections between cell biology, matrix biochemistry and tissue structure/function that may play a role in the pathomechanics of OA. PMID:26707990

  19. Experience of Implementing a Distributed Control System for Thermal and Mechanical and Electrical Equipment at the South-West CHP

    Energy Technology Data Exchange (ETDEWEB)

    Babkin, K. V., E-mail: babkin@uztec.ru; Tsvetkov, M. S.; Kostyuk, R. I.; Chugin, A. V. [SC “South-West CHP” (Russian Federation); Bilenko, V. A.; Molchanov, K. A.; Fedunov, V. V. [JSC “Interautomatika” (Russian Federation)

    2015-01-15

    Results of implementing an SPPA-T3000-based unified distributed control system for thermal and mechanical and electrical equipment at the South-West CHP are discussed. Hardware solutions for integration with local control systems, control of electrical equipment in compliance with the standards IEC 61850, Modbus RTU, and communication between the plant control system and the System Operator of the Unified Power System are described.

  20. Experience of Implementing a Distributed Control System for Thermal and Mechanical and Electrical Equipment at the South-West CHP

    International Nuclear Information System (INIS)

    Babkin, K. V.; Tsvetkov, M. S.; Kostyuk, R. I.; Chugin, A. V.; Bilenko, V. A.; Molchanov, K. A.; Fedunov, V. V.

    2015-01-01

    Results of implementing an SPPA-T3000-based unified distributed control system for thermal and mechanical and electrical equipment at the South-West CHP are discussed. Hardware solutions for integration with local control systems, control of electrical equipment in compliance with the standards IEC 61850, Modbus RTU, and communication between the plant control system and the System Operator of the Unified Power System are described

  1. High energy arcing fault fires in switchgear equipment : a literature review.

    Energy Technology Data Exchange (ETDEWEB)

    Nowlen, Steven Patrick; Brown, Jason W.; Wyant, Francis John

    2008-10-01

    In power generating plants, switchgear provide a means to isolate and de-energize specific electrical components and buses in order to clear downstream faults, perform routine maintenance, and replace necessary electrical equipment. These protective devices may be categorized by the insulating medium, such as air or oil, and are typically specified by voltage classes, i.e. low, medium, and high voltage. Given their high energy content, catastrophic failure of switchgear by means of a high energy arcing fault (HEAF) may occur. An incident such as this may lead to an explosion and fire within the switchgear, directly impact adjacent components, and possibly render dependent electrical equipment inoperable. Historically, HEAF events have been poorly documented and discussed in little detail. Recent incidents involving switchgear components at nuclear power plants, however, were scrupulously investigated. The phenomena itself is only understood on a very elementary level from preliminary experiments and theories; though many have argued that these early experiments were inaccurate due to primitive instrumentation or poorly justified methodologies and thus require re-evaluation. Within the past two decades, however, there has been a resurgence of research that analyzes previous work and modern technology. Developing a greater understanding of the HEAF phenomena, in particular the affects on switchgear equipment and other associated switching components, would allow power generating industries to minimize and possibly prevent future occurrences, thereby reducing costs associated with repair and downtime. This report presents the findings of a literature review focused on arc fault studies for electrical switching equipment. The specific objective of this review was to assess the availability of the types of information needed to support development of improved treatment methods in fire Probabilistic Risk Assessment (PRA) for nuclear power plant applications.

  2. Respiratory mechanics in brain injury: A review.

    Science.gov (United States)

    Koutsoukou, Antonia; Katsiari, Maria; Orfanos, Stylianos E; Kotanidou, Anastasia; Daganou, Maria; Kyriakopoulou, Magdalini; Koulouris, Nikolaos G; Rovina, Nikoletta

    2016-02-04

    Several clinical and experimental studies have shown that lung injury occurs shortly after brain damage. The responsible mechanisms involve neurogenic pulmonary edema, inflammation, the harmful action of neurotransmitters, or autonomic system dysfunction. Mechanical ventilation, an essential component of life support in brain-damaged patients (BD), may be an additional traumatic factor to the already injured or susceptible to injury lungs of these patients thus worsening lung injury, in case that non lung protective ventilator settings are applied. Measurement of respiratory mechanics in BD patients, as well as assessment of their evolution during mechanical ventilation, may lead to preclinical lung injury detection early enough, allowing thus the selection of the appropriate ventilator settings to avoid ventilator-induced lung injury. The aim of this review is to explore the mechanical properties of the respiratory system in BD patients along with the underlying mechanisms, and to translate the evidence of animal and clinical studies into therapeutic implications regarding the mechanical ventilation of these critically ill patients.

  3. Equipment considerations

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    Trace or ultratrace analyses require that the HPLC equipment used, including the detector, be optimal for such determinations. HPLC detectors are discussed at length in Chapter 4; discussion here is limited to the rest of the equipment. In general, commercial equipment is adequate for trace analysis; however, as the authors approach ultratrace analysis, it becomes very important to examine the equipment thoroughly and optimize it, where possible. For this reason they will review the equipment commonly used in HPLC and discuss the optimization steps. Detectability in HPLC is influenced by two factors (1): (a) baseline noise or other interferences that lead to errors in assigning the baseline absorbance; (b) peak width. 87 refs

  4. Topical review: spins and mechanics in diamond

    Science.gov (United States)

    Lee, Donghun; Lee, Kenneth W.; Cady, Jeffrey V.; Ovartchaiyapong, Preeti; Bleszynski Jayich, Ania C.

    2017-03-01

    There has been rapidly growing interest in hybrid quantum devices involving a solid-state spin and a macroscopic mechanical oscillator. Such hybrid devices create exciting opportunities to mediate interactions between disparate quantum bits (qubits) and to explore the quantum regime of macroscopic mechanical objects. In particular, a system consisting of the nitrogen-vacancy defect center (NV center) in diamond coupled to a high-quality-factor mechanical oscillator is an appealing candidate for such a hybrid quantum device, as it utilizes the highly coherent and versatile spin properties of the defect center. In this paper, we will review recent experimental progress on diamond-based hybrid quantum devices in which the spin and orbital dynamics of single defects are driven by the motion of a mechanical oscillator. In addition, we discuss prospective applications for this device, including long-range, phonon-mediated spin-spin interactions, and phonon cooling in the quantum regime. We conclude the review by evaluating the experimental limitations of current devices and identifying alternative device architectures that may reach the strong coupling regime.

  5. On the evolution of the regulatory guidance for seismic qualification of electric and active mechanical equipment for nuclear power plants

    International Nuclear Information System (INIS)

    Ng, Ching Hang; Chen, Pei-Ying

    2009-01-01

    All electric and active mechanical equipment important to safety for nuclear power plants must be seismically qualified by testing, analysis, or combined analysis and testing. The general requirements for seismic qualification of electric and active mechanical equipment in nuclear power plants are delineated in Appendix S, 'Earthquake Engineering Criteria for Nuclear Power Plants,' to Title 10, Part 50, 'Domestic Licensing of Production and Utilization Facilities,' of the Code of Federal Regulations (10 CFR Part 50), item 52.47(20) of 10 CFR 52.47, 'Contents of Applications; Technical Information,' and Appendix A, 'Seismic and Geologic Siting Criteria for Nuclear Power Plants,' to 10 CFR Part 100, 'Reactor Site Criteria.' The United States Nuclear Regulatory Commission (NRC) issued Revision 2 of Regulatory Guide (RG) 1.100, 'Seismic Qualification of Electric and Mechanical for Nuclear Power Plants' in 1988, which endorsed, with restrictions, exceptions, and clarifications, Institute of Electrical and Electronics Engineers (IEEE) Standard 344-1987 'IEEE Recommended Practice for Seismic Qualification of Class 1E Equipment for Nuclear Power Generating Stations,' for use in seismic qualification of both electric and mechanical equipment. In 2008, the staff at the NRC drafted Revision 3 of RG 1.100 to endorse, with restrictions, exceptions, and clarifications, the IEEE Std 344-2004 and the American Society of Mechanical Engineers (ASME) QME-1-2007 'Qualification of Active Mechanical Equipment Used in Nuclear Power Plants.' IEEE Std 344-2004 was an update of Std 344-1987 and ASME QME-1-2007 was an update of QME-1-2002. The major changes in IEEE Std 344-2004 and ASME QME-1-2007 include the update and expansion of criteria and procedures describing the use of experience data as a method for seismic qualification of Class 1E electric equipment (including I and C components) as well as active mechanical equipment. In this paper, the staff will compare the draft Revision 3 to

  6. Annual review of fluid mechanics. Volume 23

    International Nuclear Information System (INIS)

    Lumley, J.L.; Van Dyke, M.; Reed, H.L.

    1991-01-01

    Recent advances in theoretical, experimental, and computational fluid mechanics are discussed in a collection of annual review essays. Topics addressed include Lagrangian ocean studies, drag reduction in nature, the hydraulics of rotating strait and sill flow, analytical methods for the development of Reynolds-stress closures in turbulence, and exact solutions of the Navier-Stokes equations. Consideration is given to the theory of hurricanes, flow phenomena in CVD of thin films, particle-imaging techniques for experimental fluid mechanics, symmetry and symmetry-breaking bifurcations in fluid dynamics, turbulent mixing in stratified fluids, numerical simulation of transition in wall-bounded shear flows, fractals and multifractals in fluid turbulence, and coherent motions in the turbulent boundary layer

  7. Shooting Mechanisms in Nature: A Systematic Review.

    Directory of Open Access Journals (Sweden)

    Aimée Sakes

    Full Text Available In nature, shooting mechanisms are used for a variety of purposes, including prey capture, defense, and reproduction. This review offers insight into the working principles of shooting mechanisms in fungi, plants, and animals in the light of the specific functional demands that these mechanisms fulfill.We systematically searched the literature using Scopus and Web of Knowledge to retrieve articles about solid projectiles that either are produced in the body of the organism or belong to the body and undergo a ballistic phase. The shooting mechanisms were categorized based on the energy management prior to and during shooting.Shooting mechanisms were identified with projectile masses ranging from 1·10-9 mg in spores of the fungal phyla Ascomycota and Zygomycota to approximately 10,300 mg for the ballistic tongue of the toad Bufo alvarius. The energy for shooting is generated through osmosis in fungi, plants, and animals or muscle contraction in animals. Osmosis can be induced by water condensation on the system (in fungi, or water absorption in the system (reaching critical pressures up to 15.4 atmospheres; observed in fungi, plants, and animals, or water evaporation from the system (reaching up to -197 atmospheres; observed in plants and fungi. The generated energy is stored as elastic (potential energy in cell walls in fungi and plants and in elastic structures in animals, with two exceptions: (1 in the momentum catapult of Basidiomycota the energy is stored in a stalk (hilum by compression of the spore and droplets and (2 in Sphagnum energy is mainly stored in compressed air. Finally, the stored energy is transformed into kinetic energy of the projectile using a catapult mechanism delivering up to 4,137 J/kg in the osmotic shooting mechanism in cnidarians and 1,269 J/kg in the muscle-powered appendage strike of the mantis shrimp Odontodactylus scyllarus. The launch accelerations range from 6.6g in the frog Rana pipiens to 5,413,000g in

  8. New equipment for mechanization of warehouse operations and its use in Donbass timber yards and material stores. Novoe oborudovanie dlya mekhanizatsii skladskikh rabot i opyt ego primeneniya na lesnykh i materialinykh skladakh Donbassa

    Energy Technology Data Exchange (ETDEWEB)

    1985-01-01

    Constructional features and characteristics of new warehouse equipment are described which were developed by Donetsk Scientific Research Coal Institute in cooperation with other establishments. Experience is reviewed in the use of: turning platforms (PPG3); lifting-hoisting units (PTU); motor-hydraulic grab (MGK3M); fork-lift racks ZOD; complex KLT for mechanization of operations in timber yards; chain conveyors (T2Ts); cyclone bunkers; preparation of support timber (sawing units PRK, SRT); devices for packing and conveying timber, concrete and other materials; equipment for warehouses (racks UN, UP, KB) and others. The equipment is widely used in UkSSR Minugleprom stores and provides safer working conditions.

  9. Wire rope isolators for vibration isolation of equipment and structures – A review

    International Nuclear Information System (INIS)

    Balaji, P S; Rahman, M E; Lau, H H; Moussa, Leblouba

    2015-01-01

    Vibrations and shocks are studied using various techniques and analyzed to predict their detrimental effect on the equipment and structures. In cases, where the effects of vibration become unacceptable, it may cause structural damage and affect the operation of the equipment. Hence, adding a discrete system to isolate the vibration from source becomes necessary. The Wire Rope Isolator (WRI) can be used to effectively isolate the system from disturbing vibrations. The WRI is a type of passive isolator that exhibits nonlinear behavior. It consists of stranded wire rope held between two metal retainer bars and the metal wire rope is made up of individual wire strands that are in frictional contact with each other, hence, it is a kind of friction-type isolator. This paper compiles the research work on wire rope isolators. This paper presents the research work under two categories, namely monotonic and cyclic loading behaviors of WRI. The review also discusses the different terminologies associated with vibration isolation system and highlights the comparison between various isolation systems. (paper)

  10. Is protective equipment useful in preventing concussion? A systematic review of the literature.

    Science.gov (United States)

    Benson, B W; Hamilton, G M; Meeuwisse, W H; McCrory, P; Dvorak, J

    2009-05-01

    To determine if there is evidence that equipment use reduces sport concussion risk and/or severity. 12 electronic databases were searched using a combination of Medical Subject Headings and text words to identify relevant articles. Specific inclusion and exclusion criteria were used to select studies for review. Data extracted included design, study population, exposure/outcome measures and results. The quality of evidence was assessed based on epidemiologic criteria regarding internal and external validity (ie, strength of design, sample size/power calculation, selection bias, misclassification bias, control of potential confounding and effect modification). In total, 51 studies were selected for review. A comparison between studies was difficult due to the variability in research designs, definition of concussion, mouthguard/helmet/headgear/face shield types, measurements used to assess exposure and outcomes, and variety of sports assessed. The majority of studies were observational, with 23 analytical epidemiologic designs related to the subject area. Selection bias was a concern in the reviewed studies, as was the lack of measurement and control for potentially confounding variables. There is evidence that helmet use reduces head injury risk in skiing, snowboarding and bicycling, but the effect on concussion risk is inconclusive. No strong evidence exists for the use of mouthguards or face shields to reduce concussion risk. Evidence is provided to suggest that full facial protection in ice hockey may reduce concussion severity, as measured by time loss from competition.

  11. CEMENT BONDED COMPOSITES – A MECHANICAL REVIEW

    Directory of Open Access Journals (Sweden)

    Stephan Frybort

    2008-05-01

    Full Text Available Over the last years promising cement bonded wood composites for structural purposes have evolved. Durability, toughness, high dimen-sional stability, resistance against environmental influences such as biodegradation or weathering but also availability of the raw material as well as economic factors are features which can make cement-bonded composites superior to conventionally bonded composites. This paper reviews the relationship of diverse parameters, including density and particle size on mechanical and physical properties of cement bonded composites, based on published sources from the last 60 years. For general and recent information about bonding mechanisms, compatibility and setting problems, determination and improvement of compatibility, the used raw materials as well as accelerators are discussed. The main part deals with failure mechanisms in connection with several production parameters. Furthermore, the influence of particle size and geometry, orientation of the particles, cement-wood ratio and the effect of accelerators and treatment of the particles on modulus of elasticity, modulus of rupture as well as thickness swelling are discussed.

  12. Review of the regulation on the installation and use of X-ray equipment for medical diagnosis

    International Nuclear Information System (INIS)

    Alvarez Garcia, C.; Arguelles Sanchez, R.; Franco Artero, P.; Gil Gahete, M.; Rodriguez Marti, M.; Rueda Guerrero, M. D.; Villarroel Gonzalez-Eipe, R.

    2009-01-01

    The first regulation on the installation and use of X-ray equipment for the purposes of medical diagnosis was approved in 1991. This allowed the control of the safety of such equipment to be significantly improved. Royal Decree 1891/1991 has now been subjected to a review to update its contents and include the regulatory changes that have been incorporated in later standards, this having materialised with the Royal Decree 1085/2009, of July 3rd. (Author)

  13. Program plan for environmental qualification of mechanical and dynamic (including seismic) qualification of mechanical and electrical equipment program (EDQP)

    International Nuclear Information System (INIS)

    Weidenhamer, G.H.

    1986-06-01

    The equipment qualification program described in this plan is intended to provide the technical basis for resolving uncertainties in existing equipment qualification standards. In addition, research results are contributing to the resolution of safety issues GI-23, GI-87, USI-A44, titled, ''Reactor Coolant Pump Seal Failure,'' ''Failure of HPCI Steam Line Without Isolation,'' and ''Station Blackout,'' respectively. Also, research effort is being directed at providing information on the behavior of containment isolation valves under severe accident environments. Although the results of the latter research will not contribute to resolving uncertainties in qualification standards, it has proven cost effective to obtain this information under this program

  14. Annual review of fluid mechanics. Volume 15

    International Nuclear Information System (INIS)

    Van Dyke, M.; Wehausen, J.V.; Lumley, J.L.

    1983-01-01

    A survey of experimental results and analytical techniques for modelling various flows and the behavior of flows around flown-driven machinery is presented. Attention is given to analytical models for wind flows and power extraction by horizontal axis wind turbines. The phenomena occurring in the impact of compressible fluids with a solid body are described, as are the instabilities, pattern formation, and turbulence in flames. Homogeneous turbulence is explored, theories for autorotation by falling bodies are discussed, and attention is devoted to theoretical models for magneto-atmospheric waves and their presence in solar activity. The design characteristics of low Reynolds number airfoils are explored, and numerical and fluid mechanics formulations for integrable, chaotic, and turbulent vortex motion in two-dimensional flows are reviewed. Finally, measurements and models of turbulent wall jets for engineering purposes are examined

  15. Simplified method to evaluate seismic nozzle loads on mechanical equipment connected to unbraced piping

    International Nuclear Information System (INIS)

    Detroux, P.; Lafaille, J.P.

    1991-01-01

    After ten years of operation, the Belgian Nuclear Power Plants had to be seismically reassessed; especially, new requirements were imposed to the oldest units. The method, presented in this paper, is based on the principle that all the piping connected to the equipment is replaced by a clamped-hinged beam with or without concentrated mass and of a characteristic length depending on the diameter, schedule, mass per length of the connected piping and on the floor response spectra applicable at the location of the equipment. A theoretical justification of the method is presented for the simplest cases. The case of added concentrated mass is investigated. Finally, several comparisons with a full modal spectral analysis are presented

  16. A hybrid degradation tendency measurement method for mechanical equipment based on moving window and Grey–Markov model

    International Nuclear Information System (INIS)

    Jiang, Wei; Zhou, Jianzhong; Zheng, Yang; Liu, Han

    2017-01-01

    Accurate degradation tendency measurement is vital for the secure operation of mechanical equipment. However, the existing techniques and methodologies for degradation measurement still face challenges, such as lack of appropriate degradation indicator, insufficient accuracy, and poor capability to track the data fluctuation. To solve these problems, a hybrid degradation tendency measurement method for mechanical equipment based on a moving window and Grey–Markov model is proposed in this paper. In the proposed method, a 1D normalized degradation index based on multi-feature fusion is designed to assess the extent of degradation. Subsequently, the moving window algorithm is integrated with the Grey–Markov model for the dynamic update of the model. Two key parameters, namely the step size and the number of states, contribute to the adaptive modeling and multi-step prediction. Finally, three types of combination prediction models are established to measure the degradation trend of equipment. The effectiveness of the proposed method is validated with a case study on the health monitoring of turbine engines. Experimental results show that the proposed method has better performance, in terms of both measuring accuracy and data fluctuation tracing, in comparison with other conventional methods. (paper)

  17. A hybrid degradation tendency measurement method for mechanical equipment based on moving window and Grey-Markov model

    Science.gov (United States)

    Jiang, Wei; Zhou, Jianzhong; Zheng, Yang; Liu, Han

    2017-11-01

    Accurate degradation tendency measurement is vital for the secure operation of mechanical equipment. However, the existing techniques and methodologies for degradation measurement still face challenges, such as lack of appropriate degradation indicator, insufficient accuracy, and poor capability to track the data fluctuation. To solve these problems, a hybrid degradation tendency measurement method for mechanical equipment based on a moving window and Grey-Markov model is proposed in this paper. In the proposed method, a 1D normalized degradation index based on multi-feature fusion is designed to assess the extent of degradation. Subsequently, the moving window algorithm is integrated with the Grey-Markov model for the dynamic update of the model. Two key parameters, namely the step size and the number of states, contribute to the adaptive modeling and multi-step prediction. Finally, three types of combination prediction models are established to measure the degradation trend of equipment. The effectiveness of the proposed method is validated with a case study on the health monitoring of turbine engines. Experimental results show that the proposed method has better performance, in terms of both measuring accuracy and data fluctuation tracing, in comparison with other conventional methods.

  18. An intelligent service matching method for mechanical equipment condition monitoring using the fibre Bragg grating sensor network

    Science.gov (United States)

    Zhang, Fan; Zhou, Zude; Liu, Quan; Xu, Wenjun

    2017-02-01

    Due to the advantages of being able to function under harsh environmental conditions and serving as a distributed condition information source in a networked monitoring system, the fibre Bragg grating (FBG) sensor network has attracted considerable attention for equipment online condition monitoring. To provide an overall conditional view of the mechanical equipment operation, a networked service-oriented condition monitoring framework based on FBG sensing is proposed, together with an intelligent matching method for supporting monitoring service management. In the novel framework, three classes of progressive service matching approaches, including service-chain knowledge database service matching, multi-objective constrained service matching and workflow-driven human-interactive service matching, are developed and integrated with an enhanced particle swarm optimisation (PSO) algorithm as well as a workflow-driven mechanism. Moreover, the manufacturing domain ontology, FBG sensor network structure and monitoring object are considered to facilitate the automatic matching of condition monitoring services to overcome the limitations of traditional service processing methods. The experimental results demonstrate that FBG monitoring services can be selected intelligently, and the developed condition monitoring system can be re-built rapidly as new equipment joins the framework. The effectiveness of the service matching method is also verified by implementing a prototype system together with its performance analysis.

  19. Review on Fuel Loading Process and Performance for Advanced Fuel Handling Equipment

    International Nuclear Information System (INIS)

    Chang, Sang-Gyoon; Lee, Dae-Hee; Kim, Young-Baik; Lee, Deuck-Soo

    2007-01-01

    The fuel loading process and the performance of the advanced fuel handling equipment for OPR 1000 (Optimized Power Plant) are analyzed and evaluated. The fuel handling equipment, which acts critical processes in the refueling outage, has been improved to reduce fuel handling time. The analysis of the fuel loading process can be a useful tool to improve the performance of the fuel handling equipment effectively. Some recommendations for further improvement are provided based on this study

  20. Objectives of Experimental Validation of Mechanical Equipment for BN-1200 Reactor Plant

    International Nuclear Information System (INIS)

    Timofeev, A.V.; Lyubimov, M.A.

    2013-01-01

    Conclusion: Fabricating and testing the pilot specimens of CRDMs, mockups of main elevator units, and cantilever refueling mechanism make it possible to validate their design. Positive testing results will make it possible to start the work on developing: • final designs of the elevator and cantilever refueling mechanism; • manufacturing design documentation on CRDM prototypes

  1. Design features of selected mechanisms developed for use in Spacelab. [mechanical ground support equipment and environmental control

    Science.gov (United States)

    Inden, W.

    1979-01-01

    Selected mechanisms developed for the Spacelab program are discussed. These include: (1) the roller rail used to install/remove the Spacelab floor loaded with racks carrying experiments; (2) the foot restraint; and (3) the lithium hydroxide used for decontamination.

  2. Seismic resistance of equipment and building service systems: review of earthquake damage design requirements, and research applications in the USA

    International Nuclear Information System (INIS)

    Skjei, R.E.; Chakravartula, B.C.; Yanev, P.I.

    1979-01-01

    The history of earthquake damage and the resulting code design requirements for earthquake hazard mitigation for equipment in the USA is reviewed. Earthquake damage to essential service systems is summarized; observations for the 1964 Alaska and the 1971 San Fernando, California, earthquakes are stressed, and information from other events is included. USA building codes that reflect lessons learned from these earthquakes are discussed; brief summaries of widely used codes are presented. In conclusion there is a discussion of the desirability of adapting advanced technological concepts from the nuclear industry to equipment in conventional structures. (author)

  3. Engineering and Design: Reliability Analysis of Navigation Lock and Dam Mechanical and Electrical Equipment

    National Research Council Canada - National Science Library

    Beranek, Dwight

    2001-01-01

    This engineer technical letter (ETL) provides guidance for assessing the reliability of mechanical and electrical systems of navigation locks and dams and for establishing an engineering basis for major rehabilitation investment decisions...

  4. Pyrolysis and dehalogenation of plastics from waste electrical and electronic equipment (WEEE): a review.

    Science.gov (United States)

    Yang, Xiaoning; Sun, Lushi; Xiang, Jun; Hu, Song; Su, Sheng

    2013-02-01

    Plastics from waste electrical and electronic equipment (WEEE) have been an important environmental problem because these plastics commonly contain toxic halogenated flame retardants which may cause serious environmental pollution, especially the formation of carcinogenic substances polybrominated dibenzo dioxins/furans (PBDD/Fs), during treat process of these plastics. Pyrolysis has been proposed as a viable processing route for recycling the organic compounds in WEEE plastics into fuels and chemical feedstock. However, dehalogenation procedures are also necessary during treat process, because the oils collected in single pyrolysis process may contain numerous halogenated organic compounds, which would detrimentally impact the reuse of these pyrolysis oils. Currently, dehalogenation has become a significant topic in recycling of WEEE plastics by pyrolysis. In order to fulfill the better resource utilization of the WEEE plastics, the compositions, characteristics and dehalogenation methods during the pyrolysis recycling process of WEEE plastics were reviewed in this paper. Dehalogenation and the decomposition or pyrolysis of WEEE plastics can be carried out simultaneously or successively. It could be 'dehalogenating prior to pyrolysing plastics', 'performing dehalogenation and pyrolysis at the same time' or 'pyrolysing plastics first then upgrading pyrolysis oils'. The first strategy essentially is the two-stage pyrolysis with the release of halogen hydrides at low pyrolysis temperature region which is separate from the decomposition of polymer matrixes, thus obtaining halogenated free oil products. The second strategy is the most common method. Zeolite or other type of catalyst can be used in the pyrolysis process for removing organohalogens. The third strategy separate pyrolysis and dehalogenation of WEEE plastics, which can, to some degree, avoid the problem of oil value decline due to the use of catalyst, but obviously, this strategy may increase the cost of

  5. Recycling of non-metallic fractions from waste electrical and electronic equipment (WEEE): a review.

    Science.gov (United States)

    Wang, Ruixue; Xu, Zhenming

    2014-08-01

    The world's waste electrical and electronic equipment (WEEE) consumption has increased incredibly in recent decades, which have drawn much attention from the public. However, the major economic driving force for recycling of WEEE is the value of the metallic fractions (MFs). The non-metallic fractions (NMFs), which take up a large proportion of E-wastes, were treated by incineration or landfill in the past. NMFs from WEEE contain heavy metals, brominated flame retardant (BFRs) and other toxic and hazardous substances. Combustion as well as landfill may cause serious environmental problems. Therefore, research on resource reutilization and safe disposal of the NMFs from WEEE has a great significance from the viewpoint of environmental protection. Among the enormous variety of NMFs from WEEE, some of them are quite easy to recycle while others are difficult, such as plastics, glass and NMFs from waste printed circuit boards (WPCBs). In this paper, we mainly focus on the intractable NMFs from WEEE. Methods and technologies of recycling the two types of NMFs from WEEE, plastics, glass are reviewed in this paper. For WEEE plastics, the pyrolysis technology has the lowest energy consumption and the pyrolysis oil could be obtained, but the containing of BFRs makes the pyrolysis recycling process problematic. Supercritical fluids (SCF) and gasification technology have a potentially smaller environmental impact than pyrolysis process, but the energy consumption is higher. With regard to WEEE glass, lead removing is requisite before the reutilization of the cathode ray tube (CRT) funnel glass, and the recycling of liquid crystal display (LCD) glass is economically viable for the containing of precious metals (indium and tin). However, the environmental assessment of the recycling process is essential and important before the industrialized production stage. For example, noise and dust should be evaluated during the glass cutting process. This study could contribute

  6. Recycling of non-metallic fractions from waste electrical and electronic equipment (WEEE): A review

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ruixue; Xu, Zhenming, E-mail: zmxu@sjtu.edu.cn

    2014-08-15

    Highlights: • NMFs from WEEE were treated by incineration or land filling in the past. • Environmental risks such as heavy metals and BFRs will be the major problems during the NMFs recycling processes. • Methods and technologies of recycling the two types of NMFs from WEEE, plastics, glasses are reviewed. • More environmental impact assessment should be carried out to evaluate the environmental risks of the recycling products. - Abstract: The world’s waste electrical and electronic equipment (WEEE) consumption has increased incredibly in recent decades, which have drawn much attention from the public. However, the major economic driving force for recycling of WEEE is the value of the metallic fractions (MFs). The non-metallic fractions (NMFs), which take up a large proportion of E-wastes, were treated by incineration or landfill in the past. NMFs from WEEE contain heavy metals, brominated flame retardant (BFRs) and other toxic and hazardous substances. Combustion as well as landfill may cause serious environmental problems. Therefore, research on resource reutilization and safe disposal of the NMFs from WEEE has a great significance from the viewpoint of environmental protection. Among the enormous variety of NMFs from WEEE, some of them are quite easy to recycle while others are difficult, such as plastics, glass and NMFs from waste printed circuit boards (WPCBs). In this paper, we mainly focus on the intractable NMFs from WEEE. Methods and technologies of recycling the two types of NMFs from WEEE, plastics, glass are reviewed in this paper. For WEEE plastics, the pyrolysis technology has the lowest energy consumption and the pyrolysis oil could be obtained, but the containing of BFRs makes the pyrolysis recycling process problematic. Supercritical fluids (SCF) and gasification technology have a potentially smaller environmental impact than pyrolysis process, but the energy consumption is higher. With regard to WEEE glass, lead removing is requisite

  7. Efficacy and efficiency of poultry carcass composting using different mechanical mixing equipment for avian influenza outbreaks

    Directory of Open Access Journals (Sweden)

    Jennifer Elizabeth Keaten

    2017-05-01

    Full Text Available Background and Aim: Avian influenza (AI is a viral disease that caused the largest animal disease outbreak in the history of US agriculture. There are several disposal methods of AI infected poultry carcasses available in the US, which include on-site burial, landfill, incineration, rendering, and composting. Of these methods, composting is the most environmentally friendly and poses a low risk for biosecurity. The United States Department of Agriculture (USDA has developed a comprehensive plan for composting AI infected carcasses. The current protocols have the potential for areas of anaerobic pockets within the windrow due to inadequate mixing and the large carcass size of whole birds. This could lead to ineffective virus neutralization or prolonged composting times and higher resource costs. The purpose of this project was to determine if using a horizontal mixer (HM wagon to mix composting ingredients or a vertical mixer (VM wagon to mix and cut up the compositing ingredients is an economical and timely means to accelerate the tissue break-down and obtain optimal temperatures for poultry carcass composting during an AI outbreak. Materials and Methods: A replicated trial with three treatments, HM, conventional layering (CL and VM, and three replications was initiated at the Compost Research and Education Center part of the University of Maine Forest and Agricultural Experimental Station called High Moor Farm. Daily temperatures and screened core sample weights (screen weights on day 0, 16, and 30 were recorded for each of the compost piles. The time to build each replication was recorded and used to help calculate the cost of each method. Data on equipment, carbon material and labor costs were collected from private contractors from the 2014 to 2016 highly pathogenic AI (HPAI outbreak and used to compare costs between methods. Results: All treatment methods reached USDA protocol temperatures to neutralize the HPAI virus. Screen weights for

  8. 47 CFR 76.930 - Initiation of review of basic cable service and equipment rates.

    Science.gov (United States)

    2010-10-01

    ... rates for the basic service tier and associated equipment with a franchising authority within 30 days of receiving written notification from the franchising authority that the franchising authority has been...

  9. A simplified model of natural and mechanical removal to estimate cleanup equipment efficiency

    International Nuclear Information System (INIS)

    Lehr, W.

    2001-01-01

    Oil spill response organizations rely on modelling to make decisions in offshore response operations. Models are used to test different cleanup strategies and to measure the expected cost of cleanup and the reduction in environmental impact. The oil spill response community has traditionally used the concept of worst case scenario in developing contingency plans for spill response. However, there are many drawbacks to this approach. The Hazardous Materials Response Division of the National Oceanic and Atmospheric Administration in Cooperation with the U.S. Navy Supervisor of Salvage and Diving has developed a Trajectory Analysis Planner (TAP) which will give planners the tool to try out different cleanup strategies and equipment configurations based upon historical wind and current conditions instead of worst-case scenarios. The spill trajectory model is a classic example in oil spill modelling that uses advanced non-linear three-dimensional hydrodynamical sub-models to estimate surface currents under conditions where oceanographic initial conditions are not accurately known and forecasts of wind stress are unreliable. In order to get better answers, it is often necessary to refine input values rather than increasing the sophistication of the hydrodynamics. This paper described another spill example where the level of complexity of the algorithms needs to be evaluated with regard to the reliability of the input, the sensitivity of the answers to input and model parameters, and the comparative reliability of other algorithms in the model. 9 refs., 1 fig

  10. Remote mechanized equipment for the repair and replacement of boiling water reactor recirculation loop piping

    International Nuclear Information System (INIS)

    Mauser, D.; Busch, D.F.

    1983-01-01

    Equipment has been assembled for the remote repair or replacement of boiling water reactor nuclear plant piping in the diameter range of 4 to 28 inches (10-71 cm). The objectives of this program were to produce high-quality pipe welds, reduce plant downtime, and reduce man-rem exposure. The repair strategy was to permit repair personnel to install and check out the repair subsystems and then leave the radiation zone allowing the operations to be conducted at a distance of up to 300 feet (91 m) from the operator. The complete repair system comprises subsystems for pipe severing, dimensional gaging, joint preparation, counterboring, welding, postweld nondestructive inspection (conceptual design), and audio, electronic, and visual monitoring of all operations. Components for all subsystems, excluding those for postweld nondestructive inspection, were purchased and modified as needed for integration into the repair system. Subsystems were designed for two sizes of Type 304 stainless steelpipe. For smaller, 12-inch-diameter (30.5 cm) pipe, severing is accomplished by a power hack saw and joint preparation and counterboring by an internally mounted lathe. The 22-inch-diameter (56 cm) pipe is severed, prepared, and counterbored using an externally mounted, single-point machining device. Dimensional gaging is performed to characterize the pipe geometry relative to a fixed external reference surface, allowing the placement of the joint preparation and the counterbore to be optimized. For both pipe sizes, a track-mounted gas tungsten-arc welding head with filler wire feed is used

  11. The review conference mechanism in nuclear law: issues and opportunities

    International Nuclear Information System (INIS)

    Stoiber, C.

    2009-01-01

    This paper seeks to assess the major issues arising from reliance on the review conference mechanism as a measure for enhancing the effectiveness of multilateral legal instruments, particularly those in the nuclear field. In view of the perceived failure of the 2005 review conference of the Parties to the Treaty on the non-proliferation of nuclear weapons and the need to avoid a similar result at the upcoming 2010 review conference, it is hoped that this analysis will provide a timely review of the review conference mechanism. (N.C.)

  12. Respiratory mechanics in brain injury: A review

    OpenAIRE

    Koutsoukou, Antonia; Katsiari, Maria; Orfanos, Stylianos E; Kotanidou, Anastasia; Daganou, Maria; Kyriakopoulou, Magdalini; Koulouris, Nikolaos G; Rovina, Nikoletta

    2016-01-01

    Several clinical and experimental studies have shown that lung injury occurs shortly after brain damage. The responsible mechanisms involve neurogenic pulmonary edema, inflammation, the harmful action of neurotransmitters, or autonomic system dysfunction. Mechanical ventilation, an essential component of life support in brain-damaged patients (BD), may be an additional traumatic factor to the already injured or susceptible to injury lungs of these patients thus worsening lung injury, in case ...

  13. Time expenditure in computer aided time studies implemented for highly mechanized forest equipment

    Directory of Open Access Journals (Sweden)

    Elena Camelia Mușat

    2016-06-01

    Full Text Available Time studies represent important tools that are used in forest operations research to produce empirical models or to comparatively assess the performance of two or more operational alternatives with the general aim to predict the performance of operational behavior, choose the most adequate equipment or eliminate the useless time. There is a long tradition in collecting the needed data in a traditional fashion, but this approach has its limitations, and it is likely that in the future the use of professional software would be extended is such preoccupations as this kind of tools have been already implemented. However, little to no information is available in what concerns the performance of data analyzing tasks when using purpose-built professional time studying software in such research preoccupations, while the resources needed to conduct time studies, including here the time may be quite intensive. Our study aimed to model the relations between the variation of time needed to analyze the video-recorded time study data and the variation of some measured independent variables for a complex organization of a work cycle. The results of our study indicate that the number of work elements which were separated within a work cycle as well as the delay-free cycle time and the software functionalities that were used during data analysis, significantly affected the time expenditure needed to analyze the data (α=0.01, p<0.01. Under the conditions of this study, where the average duration of a work cycle was of about 48 seconds and the number of separated work elements was of about 14, the speed that was usedto replay the video files significantly affected the mean time expenditure which averaged about 273 seconds for half of the real speed and about 192 seconds for an analyzing speed that equaled the real speed. We argue that different study designs as well as the parameters used within the software are likely to produce

  14. Lawrence Livermore National Laboratory (LLNL) Experimental Test Site (Site 300) Salinity Evaluation and Minimization Plan for Cooling Towers and Mechanical Equipment Discharges

    Energy Technology Data Exchange (ETDEWEB)

    Daily III, W D

    2010-02-24

    This document was created to comply with the Central Valley Regional Water Quality Control Board (CVRWQCB) Waste Discharge Requirement (Order No. 98-148). This order established new requirements to assess the effect of and effort required to reduce salts in process water discharged to the subsurface. This includes the review of technical, operational, and management options available to reduce total dissolved solids (TDS) concentrations in cooling tower and mechanical equipment water discharges at Lawrence Livermore National Laboratory's (LLNL's) Experimental Test Site (Site 300) facility. It was observed that for the six cooling towers currently in operation, the total volume of groundwater used as make up water is about 27 gallons per minute and the discharge to the subsurface via percolation pits is 13 gallons per minute. The extracted groundwater has a TDS concentration of 700 mg/L. The cooling tower discharge concentrations range from 700 to 1,400 mg/L. There is also a small volume of mechanical equipment effluent being discharged to percolation pits, with a TDS range from 400 to 3,300 mg/L. The cooling towers and mechanical equipment are maintained and operated in a satisfactory manner. No major leaks were identified. Currently, there are no re-use options being employed. Several approaches known to reduce the blow down flow rate and/or TDS concentration being discharged to the percolation pits and septic systems were reviewed for technical feasibility and cost efficiency. These options range from efforts as simple as eliminating leaks to implementing advanced and innovative treatment methods. The various options considered, and their anticipated effect on water consumption, discharge volumes, and reduced concentrations are listed and compared in this report. Based on the assessment, it was recommended that there is enough variability in equipment usage, chemistry, flow rate, and discharge configurations that each discharge location at Site 300

  15. Lawrence Livermore National Laboratory (LLNL) Experimental Test Site (Site 300) Salinity Evaluation and Minimization Plan for Cooling Towers and Mechanical Equipment Discharges

    International Nuclear Information System (INIS)

    Daily, W.D. III

    2010-01-01

    This document was created to comply with the Central Valley Regional Water Quality Control Board (CVRWQCB) Waste Discharge Requirement (Order No. 98-148). This order established new requirements to assess the effect of and effort required to reduce salts in process water discharged to the subsurface. This includes the review of technical, operational, and management options available to reduce total dissolved solids (TDS) concentrations in cooling tower and mechanical equipment water discharges at Lawrence Livermore National Laboratory's (LLNL's) Experimental Test Site (Site 300) facility. It was observed that for the six cooling towers currently in operation, the total volume of groundwater used as make up water is about 27 gallons per minute and the discharge to the subsurface via percolation pits is 13 gallons per minute. The extracted groundwater has a TDS concentration of 700 mg/L. The cooling tower discharge concentrations range from 700 to 1,400 mg/L. There is also a small volume of mechanical equipment effluent being discharged to percolation pits, with a TDS range from 400 to 3,300 mg/L. The cooling towers and mechanical equipment are maintained and operated in a satisfactory manner. No major leaks were identified. Currently, there are no re-use options being employed. Several approaches known to reduce the blow down flow rate and/or TDS concentration being discharged to the percolation pits and septic systems were reviewed for technical feasibility and cost efficiency. These options range from efforts as simple as eliminating leaks to implementing advanced and innovative treatment methods. The various options considered, and their anticipated effect on water consumption, discharge volumes, and reduced concentrations are listed and compared in this report. Based on the assessment, it was recommended that there is enough variability in equipment usage, chemistry, flow rate, and discharge configurations that each discharge location at Site 300 should be

  16. Review: The fundamental mechanism of aqueous contaminant ...

    African Journals Online (AJOL)

    Contaminant co-precipitation with continuously generated and transformed iron corrosion products has received relatively little attention in comparison to other possible removal mechanisms (adsorption, oxidation, precipitation) in Fe0/H2O systems at near neutral pH values. A primary reason for this is that the use of ...

  17. Selection of equipment for equipment qualification

    International Nuclear Information System (INIS)

    Torr, K.G.

    1989-01-01

    This report describes the methodology applied in selecting equipment in the special safety systems for equipment qualification in the CANDU 600 MW nuclear generating stations at Gentilly 2 and Point Lepreau. Included is an explanation of the selection procedure adopted and the rationale behind the criteria used in identifying the equipment. The equipment items on the list have been grouped into three priority categories as a planning aid to AECB staff for a review of the qualification status of the special safety systems

  18. Effect of training and lifting equipment for preventing back pain in lifting and handling: systematic review

    NARCIS (Netherlands)

    Martimo, Kari-Pekka; Verbeek, Jos; Karppinen, Jaro; Furlan, Andrea D.; Takala, Esa-Pekka; Kuijer, P. Paul F. M.; Jauhiainen, Merja; Viikari-Juntura, Eira

    2008-01-01

    To determine whether advice and training on working techniques and lifting equipment prevent back pain in jobs that involve heavy lifting. Medline, Embase, CENTRAL, Cochrane Back Group's specialised register, CINAHL, Nioshtic, CISdoc, Science Citation Index, and PsychLIT were searched up to

  19. Review of the application of ergonomics design of trackless mining equipment (TME) - lessons and challenges

    CSIR Research Space (South Africa)

    James, JP

    2007-06-01

    Full Text Available the design of trackless mining equipment (TME) is poor, with improvised seating, poor cabin layouts and sub-standard display instrumentation. This paper will present the key findings of two studies assessing ergonomics risk factors associated with automated...

  20. Design review of the INTOR mechanical configuration

    International Nuclear Information System (INIS)

    Brown, T.G.

    1981-01-01

    The INTOR conceptual design has been carried out by design teams working in the home countries with periodic workshop sessions in Vienna to review the ongoing work and to make decisions on the evolving design. The decisions taken at each workshop session were then incorporated into each national design activity, so that the four national design contributions would progressively converge toward a single design with increasingly greater detail. This paper defines the final INTOR configuration that has evolved during the conceptual design phase, defining the major system design alternatives that were considered and the rationale for selecting the final system configuration

  1. Resonance-Based Sparse Signal Decomposition and its Application in Mechanical Fault Diagnosis: A Review.

    Science.gov (United States)

    Huang, Wentao; Sun, Hongjian; Wang, Weijie

    2017-06-03

    Mechanical equipment is the heart of industry. For this reason, mechanical fault diagnosis has drawn considerable attention. In terms of the rich information hidden in fault vibration signals, the processing and analysis techniques of vibration signals have become a crucial research issue in the field of mechanical fault diagnosis. Based on the theory of sparse decomposition, Selesnick proposed a novel nonlinear signal processing method: resonance-based sparse signal decomposition (RSSD). Since being put forward, RSSD has become widely recognized, and many RSSD-based methods have been developed to guide mechanical fault diagnosis. This paper attempts to summarize and review the theoretical developments and application advances of RSSD in mechanical fault diagnosis, and to provide a more comprehensive reference for those interested in RSSD and mechanical fault diagnosis. Followed by a brief introduction of RSSD's theoretical foundation, based on different optimization directions, applications of RSSD in mechanical fault diagnosis are categorized into five aspects: original RSSD, parameter optimized RSSD, subband optimized RSSD, integrated optimized RSSD, and RSSD combined with other methods. On this basis, outstanding issues in current RSSD study are also pointed out, as well as corresponding instructional solutions. We hope this review will provide an insightful reference for researchers and readers who are interested in RSSD and mechanical fault diagnosis.

  2. Annual review of fluid mechanics. Volume 22

    International Nuclear Information System (INIS)

    Lumley, J.L.; Van Dyke, M.; Reed, H.L.

    1990-01-01

    Topics presented include rapid granular flows, issues in viscoelastic fluid mechanics, wave loads on offshore structures, boundary layers in the general ocean circulation, parametrically forced surface waves, wave-mean flow interactions in the equatorial ocean, and local and global instabilities in spatially developing flows. Also presented are aerodynamics of human-powered flight, aerothermodynamics and transition in high-speed wind tunnels at NASA-Langley, wakes behind blunt bodies, and mixing, chaotic advection, and turbulence. Also addressed are the history of the Reynolds number, panel methods in computational fluid dynamics, numerical multipole and boundary integral equation techniques in Stokes flow, plasma turbulence, optical rheometry, and viscous-flow paradoxes

  3. The status and development of treatment techniques of typical waste electrical and electronic equipment in China: a review.

    Science.gov (United States)

    He, Yunxia; Xu, Zhenming

    2014-04-01

    A large quantity of waste electrical and electronic equipment (WEEE) is being generated because technical innovation promotes the unceasing renewal of products. China's household appliances and electronic products have entered the peak of obsolescence. Due to lack of technology and equipment, recycling of WEEE is causing serious environment pollution. In order to achieve the harmless disposal and resource utilization of WEEE, researchers have performed large quantities of work, and some demonstration projects have been built recently. In this paper, the treatment techniques of typical WEEE components, including printed circuit boards, refrigerator cabinets, toner cartridges, cathode ray tubes, liquid crystal display panels, batteries (Ni-Cd and Li-ion), hard disk drives, and wires are reviewed. An integrated recycling system with environmentally friendly and highly efficient techniques for processing WEEE is proposed. The orientation of further development for WEEE recycling is also proposed.

  4. Mechanical properties on geopolymer brick: A review

    Science.gov (United States)

    Deraman, L. M.; Abdullah, M. M. A.; Ming, L. Y.; Ibrahim, W. M. W.; Tahir, M. F. M.

    2017-09-01

    Bricks has stand for many years as durable construction substantial, especially in the area of civil engineering to construct buildings. Brick commonly used in the structure of buildings as a construction wall, cladding, facing perimeter, paving, garden wall and flooring. The contribution of ordinary Portland cement (OPC) in cement bricks production worldwide to greenhouse gas emissions. Due to this issue, some researchers have done their study with other materials to produce bricks, especially as a by-product material. Researchers take effort in this regard to synthesizing from by-product materials such as fly ash, bottom ash and kaolin that are rich in silicon and aluminium in the development of inorganic alumina-silicate polymer, called geopolymer Geopolymer is a polymerization reaction between various aluminosilicate oxides with silicates solution or alkali hydroxide solution forming polymerized Si-O-Al-O bonds. This paper summarized some research finding of mechanical properties of geopolymer brick using by-product materials.

  5. Mechanisms of action of lumbar supports : a systematic review

    NARCIS (Netherlands)

    van Poppel, M N; de Looze, M P; Koes, B W; Smid, T; Bouter, L M

    2000-01-01

    STUDY DESIGN: A systematic review and meta-analysis of studies on the putative mechanisms of action of lumbar supports in lifting activities. OBJECTIVE: To summarize the evidence bearing on the putative mechanisms of action of lumbar supports. SUMMARY OF BACKGROUND DATA: A restriction of trunk

  6. Mechanisms of action of lumbar supports: a sytematic review

    NARCIS (Netherlands)

    van Poppel-Bruinvels, M.N.M.; de Looze, M.P.; Koes, B.W.; Smid, T.; Bouter, L.M.

    2000-01-01

    Study Design. A systematic review and meta-analysis of studies on the putative mechanisms of action of lumbar supports in lifting activities. Objective. To summarize the evidence bearing on the putative mechanisms of action of lumbar supports. Summary of Background Data. A restriction of trunk

  7. Review of Mechanisms and Theories of Aging

    Directory of Open Access Journals (Sweden)

    Gholam Reza Azari

    2006-10-01

    Full Text Available Several factors have incentive role for study of aging which includes increasing of the average and maximum of human life span, the increase in percentage of elderly in the societies and proportion of the national expenditure utilized by them. The Recent views of aging indicating that aging is extremely a complex multifactorial process despite of earlier views about definite cause aging like gene or decline of a key factor(1. This brief review tries to inspect aging at the molecular, cellular, and systemic levels; and consider interaction between genetic and environmental factors. Evolutionary theories argue that aging results from a decline in the force of natural selection. On the other hand, molecular theories emphasis on the genetically regulation of aging and argue that aging results from changing in genes. There are cellular theories that telomere theory is most famous. Stress induced aging is in this group too. free radical theory is next known way for cellular damages. Finally, we see systemic theories that contain two main groups, neuroendocrine and immunologic theories.

  8. Reaction mechanisms in cellulose pyrolysis: a literature review

    Energy Technology Data Exchange (ETDEWEB)

    Molton, P.M.; Demmitt, T.F.

    1977-08-01

    A bibliographic review of 195 references is presented outlining the history of the research into the mechanisms of cellulose pyrolysis. Topics discussed are: initial product identification, mechanism of initial formation of levoglucosan, from cellulose and from related compounds, decomposition of cellulose to other compounds, formation of aromatics, pyrolysis of levoglucosan, crosslinking of cellulose, pyrolytic reactions of cellulose derivatives, and the effects of inorganic salts on the pyrolysis mechanism. (JSR)

  9. Mechanical Restraint - Which Interventions Prevent Episodes of Mechanical Restraint? - A Systematic Review

    DEFF Research Database (Denmark)

    Bak, Jesper; Brandt-Christensen, Anne Mette; Sestoft, Dorte Maria

    2012-01-01

    PURPOSE:  To identify interventions preventing mechanical restraints. DESIGN AND METHODS:  Systematic review of international research papers dealing with mechanical restraint. The review combines qualitative and quantitative research in a new way, describing the quality of evidence and the effect...... of intervention. FINDINGS:  Implementation of cognitive milieu therapy, combined interventions, and patient-centered care were the three interventions most likely to reduce the number of mechanical restraints. PRACTICE IMPLICATIONS:  There is a lack of high-quality and effective intervention studies. This leaves...... patients and metal health professionals with uncertainty when choosing interventions in an attempt to prevent mechanical restraints....

  10. Mechanical profiles of murder and murderers: An extensive review.

    Science.gov (United States)

    Kamaluddin, M R; Md Shariff, N S; Mat Saat, G A

    2018-04-01

    Murder is an extreme form of violent crime which occurs across all social, cultural, and ethnic spheres. It is therefore, crucial to understand the nature and the extent of mechanical profiles of murder and murderers. The purpose of this article is to review such critical aspects of murder in a nutshell. An archival research methodology was employed in this study where relevant search for literatures on these mechanical aspects related to murder was made across search engines such as Google Scholar and Elsevier with relevant articles selected for this review. This review discusses in an in-depth manner, pivotal mechanical profiles which include motives, methods of killing, choice of weapon, settings, targeted body parts, and murder victim concealment. In-depth understanding of each mechanical aspect offers an opportunity to the public at large to expand their knowledge on murder prevention manners which is vital for crime prevention efforts in the future.

  11. BOOK REVIEW: Statistical Mechanics of Turbulent Flows

    Science.gov (United States)

    Cambon, C.

    2004-10-01

    This is a handbook for a computational approach to reacting flows, including background material on statistical mechanics. In this sense, the title is somewhat misleading with respect to other books dedicated to the statistical theory of turbulence (e.g. Monin and Yaglom). In the present book, emphasis is placed on modelling (engineering closures) for computational fluid dynamics. The probabilistic (pdf) approach is applied to the local scalar field, motivated first by the nonlinearity of chemical source terms which appear in the transport equations of reacting species. The probabilistic and stochastic approaches are also used for the velocity field and particle position; nevertheless they are essentially limited to Lagrangian models for a local vector, with only single-point statistics, as for the scalar. Accordingly, conventional techniques, such as single-point closures for RANS (Reynolds-averaged Navier-Stokes) and subgrid-scale models for LES (large-eddy simulations), are described and in some cases reformulated using underlying Langevin models and filtered pdfs. Even if the theoretical approach to turbulence is not discussed in general, the essentials of probabilistic and stochastic-processes methods are described, with a useful reminder concerning statistics at the molecular level. The book comprises 7 chapters. Chapter 1 briefly states the goals and contents, with a very clear synoptic scheme on page 2. Chapter 2 presents definitions and examples of pdfs and related statistical moments. Chapter 3 deals with stochastic processes, pdf transport equations, from Kramer-Moyal to Fokker-Planck (for Markov processes), and moments equations. Stochastic differential equations are introduced and their relationship to pdfs described. This chapter ends with a discussion of stochastic modelling. The equations of fluid mechanics and thermodynamics are addressed in chapter 4. Classical conservation equations (mass, velocity, internal energy) are derived from their

  12. A comprehensive review of rollover accidents involving vehicles equipped with Electronic Stability Control (ESC) systems.

    Science.gov (United States)

    Padmanaban, Jeya; Shields, Leland E; Scheibe, Robert R; Eyges, Vitaly E

    2008-10-01

    This study investigated 478 police accident reports from 9 states to examine and characterize rollover crashes involving ESC-equipped vehicles. The focus was on the sequence of critical events leading to loss of control and rollover, and the interactions between the accident, driver, and environment. Results show that, while ESC is effective in reducing loss of control leading to certain rollover crashes, its effectiveness is diminished in others, particularly when the vehicle departs the roadway or when environmental factors such as slick road conditions or driver factors such as speeding, distraction, fatigue, impairment, or overcorrection are present.

  13. Solvent extraction equipment evaluation study. Part 1. Review of the literature

    Energy Technology Data Exchange (ETDEWEB)

    Geier, R.G.; Browne, L.M. (comps.)

    1977-01-01

    This is Part 1 of a three-part document that reviews the solvent extraction contactors available for use in radiochemical reprocessing plants. The three parts are: Part 1: A Review of the Literature, Part 2: Workshop Proceedings, Part 3: A Summary. The main objective of the document is to provide an information base to aid in contactor selection and design of future reprocessing plants. The Literature Review (Part 1) brings together scattered data on all major contactors in use today. It contains an annotated bibliography of the citations used in the review and a complete listing of all the citations screened prior to the review. These bibliographies should aid in determining which reports would be most useful if additional information is desired.

  14. Solvent extraction equipment evaluation study. Part 1. Review of the literature

    International Nuclear Information System (INIS)

    Geier, R.G.; Browne, L.M.

    1977-01-01

    This is Part 1 of a three-part document that reviews the solvent extraction contactors available for use in radiochemical reprocessing plants. The three parts are: Part 1: A Review of the Literature, Part 2: Workshop Proceedings, Part 3: A Summary. The main objective of the document is to provide an information base to aid in contactor selection and design of future reprocessing plants. The Literature Review (Part 1) brings together scattered data on all major contactors in use today. It contains an annotated bibliography of the citations used in the review and a complete listing of all the citations screened prior to the review. These bibliographies should aid in determining which reports would be most useful if additional information is desired

  15. A Critical Review of Landslide Failure Mechanisms

    Science.gov (United States)

    Stead, D.; Wolter, A.; Clague, J. J.

    2011-12-01

    During the last ten years several comprehensive geotechnical studies have been completed on major historic landslides including Randa in Switzerland, Frank in Canada, Aknes in Norway, La Clapiere in France and Vaiont in Italy. In addition, numerous researchers have documented deep-seated gravitational deformations and a wide variety of large prehistoric rock slope failures. The information provided by these studies is evidence of the significant advances made in our ability to map, monitor and model landslides. Over the same period, the mining industry has developed large open pits with slope heights exceeding 1000 m that provide important analogues to high mountain slopes. In this paper we analyse data from the literature to illustrate the importance of brittle fracture, 3D controls, anisotropy, overburden stress, geomorphic processes, groundwater and temperature in major landslides and provide some indicators as to the research required to further understand the complexity of rock slope failure mechanisms. The nature of the landslide failure surface has received inadequate attention in the past, with failure surfaces typically considered in 2D and simulated as discrete, smooth and often planar features. Current work shows that failure surfaces are inherently three-dimensional and have much structural variability across the area of the landslide scarp, reflecting complex structural histories. Such anisotropy and variations may result in multiple events or distinct blocks that move at different rates. Just as most failure surfaces vary spatially, they may also change with depth and thus should more realistically be considered failure zones rather than discrete surfaces. The increasing recognition of the importance of step-path failures, internal dilation and brittle fracture are indicative of the complexity in slope failure surfaces. Related to the variation in failure surface characteristics is the importance of 3D rotational displacements and both the

  16. Imaging of placental transport mechanisms: a review.

    Science.gov (United States)

    Sölder, Elisabeth; Rohr, Irena; Kremser, Christian; Hutzler, Peter; Debbage, Paul L

    2009-05-01

    Functional analysis of material transfers requires precise statement of residence times in each tissue compartment. For the placenta, neither extractive biochemistry, isotope partitioning, nor mass-based quantitative assays provide adequate spatial resolution to allow the necessary precision. Dual-perfusion assays of material transfer in isolated placental cotyledons provide time-series data for two compartments, the maternal and fetal blood, but fail to distinguish the two cellular compartments (syncytiotrophoblast, fetal endothelium) which actively regulate rates of transfer in each direction for essentially every important molecule type. At present, no definitive technology exists for functional analysis of placental transfer functions. The challenge in developing such a technology lies in the exquisitely small and delicate structures involved, which are scaled at cellular and subcellular sizes (between 50 nm and 50 microm). The only available technologies attaining this high spatial resolution are imaging technologies, primarily light and electron microscopy. To achieve the high-quality images necessary, confocal laser scanning microscopy (CLSM) is required, to provide a uniform optical sectioning plane. In turn, this requires relatively high fluorescence intensities. Design of an adequate technology therefore bases on CLSM imaging fluorochrome-tagged tracers. The temporal resolution necessary to analyse placental material transfers is expected to be of the order of a few seconds, so that conventional wet-fixation protocols are too slow. For adequately rapid fixation, snap-freezing is required. As part of this review we report results obtained from an appropriately designed experimental protocol, analysed by CLSM and transmission electron microscopy (TEM). The images acquired were tested for uniformity of illumination and fluorescence emission strength. Relevant data was encoded in the green channel of the trichrome images obtained, and this was thresholded by

  17. REVIEW OF EQUIPMENT USED IN RUSSIAN PRACTICE FOR ACCOUNTING MEASUREMENTS OF NUCLEAR MATERIALS

    International Nuclear Information System (INIS)

    NEYMOTIN, L.

    1999-01-01

    The objective of this work was to analyze instrumentation and methodologies used at Russian nuclear facilities for measurement of item nuclear materials, materials in bulk form, and waste streams; specify possibilities for the application of accounting measurements; and develop recommendations for improvement. The major steps and results: Representative conversion, enrichment (gas centrifuge), fuel fabrication, spent fuel reprocessing, and chemical-metallurgical production facilities in Russia were selected; Full lists of nuclear materials were prepared; Information about measurement methods and instrumentation for each type of nuclear material were gathered; and Recommendations on methodological and instrumentation support of accounting measurements for all types of materials were formulated. The analysis showed that the existing measurement methods and instrumentation serve mostly to support the technological process control and nuclear and radiation safety control. Requirements for these applications are lower than requirements for MC and A applications. To improve the state of MC and A at Russian nuclear facilities, significant changes in instrumentation support will be required, specifically in weighing equipment, volume measurements, and destructive and non-destructive analysis equipment, along with certified reference materials

  18. Review of material recovery from used electric and electronic equipment-alternative options for resource conservation.

    Science.gov (United States)

    Friege, Henning

    2012-09-01

    For waste from electric and electronic equipment, the WEEE Directive stipulates the separate collection of electric and electronic waste. As to new electric and electronic devices, the Restriction of Hazardous Substances (RoHS) Directive bans the use of certain chemicals dangerous for man and environment. From the implementation of the WEEE directive, many unsolved problems have been documented: poor collection success, emission of dangerous substances during collection and recycling, irretrievable loss of valuable metals among others. As to RoHS, data from the literature show a satisfying success. The problems identified in the process can be reduced to some basic dilemmas at the borders between waste management, product policy and chemical safety. The objectives of the WEEE Directive and the specific targets for use and recycling of appliances are not consistent. There is no focus on scarce resources. Extended producer responsibility is not sufficient to guarantee sustainable waste management. Waste management reaches its limits due to problems of implementation but also due to physical laws. A holistic approach is necessary looking at all branch points and sinks in the stream of used products and waste from electric and electronic equipment. This may be done with respect to the general rules for sustainable management of material streams covering the three dimensions of sustainable policy. The relationships between the players in the field of electric and electronic devices have to be taken into account. Most of the problems identified in the implementation process will not be solved by the current amendment of the WEEE Directive.

  19. Woody biomass comminution and sorting - a review of mechanical methods

    Energy Technology Data Exchange (ETDEWEB)

    Eriksson, Gunnar [Swedish Univ. of Agricultural Sciences, Dept. of Forest Resource Management, Umeaa (Sweden)], e-mail: gunnar.eriksson@slu.se

    2012-11-01

    The increased demand for woody biomass for heat and electricity and biorefineries means that each bio component must be used efficiently. Any increase in raw material supply in the short term is likely to require the use of trees from early thinnings, logging residues and stumps, assortments of low value compared to stemwood. However, sorting of the novel materials into bio components may increase their value considerably. The challenge is to 1) maximise the overall values of the different raw material fractions for different users, 2) minimise costs for raw material extraction, processing, storage and transportation. Comminution of the raw material (e.g. to chips, chunks, flakes and powder) and sorting the bio components (e.g. separating bark from pulp chips and separating alkali-rich needles and shots for combustion and gasification applications) are crucial processes in this optimisation. The purpose of this study has been to make a literature review of principles for comminution and sorting, with an emphasis on mechanical methods suitable outside industries. More efficient comminution methods can be developed when the wood is to a larger extent cut along the fibre direction, and closer to the surface (with less pressure to the sides of the knife). By using coarse comminution (chunking) rather than fine comminution (chipping), productivity at landings can be increased and energy saved, the resulting product will have better storage and drying properties. At terminals, any further comminution (if necessary) could use larger-scale equipment of higher efficiency. Rolls and flails can be used to an increasing extent for removing foliage and twigs, possibly in the terrain (for instance fitted on grapples). Physical parameters used for sorting of the main components of trees include particle size, density and shape (aerodynamic drag and lift), optical and IR properties and X-ray fluorescence. Although methods developed for pulp chip production from whole trees may not

  20. A Global Review of Incentive Programs to Accelerate Energy-Efficient Appliances and Equipment

    Energy Technology Data Exchange (ETDEWEB)

    de la Rue du Can, Stephane; Phadke, Amol; Leventis, Greg; Gopal, Anand

    2013-08-01

    Incentive programs are an essential policy tool to move the market toward energy-efficient products. They offer a favorable complement to mandatory standards and labeling policies by accelerating the market penetration of energy-efficient products above equipment standard requirements and by preparing the market for increased future mandatory requirements. They sway purchase decisions and in some cases production decisions and retail stocking decisions toward energy-efficient products. Incentive programs are structured according to their regulatory environment, the way they are financed, by how the incentive is targeted, and by who administers them. This report categorizes the main elements of incentive programs, using case studies from the Major Economies Forum to illustrate their characteristics. To inform future policy and program design, it seeks to recognize design advantages and disadvantages through a qualitative overview of the variety of programs in use around the globe. Examples range from rebate programs administered by utilities under an Energy-Efficiency Resource Standards (EERS) regulatory framework (California, USA) to the distribution of Eco-Points that reward customers for buying efficient appliances under a government recovery program (Japan). We found that evaluations have demonstrated that financial incentives programs have greater impact when they target highly efficient technologies that have a small market share. We also found that the benefits and drawbacks of different program design aspects depend on the market barriers addressed, the target equipment, and the local market context and that no program design surpasses the others. The key to successful program design and implementation is a thorough understanding of the market and effective identification of the most important local factors hindering the penetration of energy-efficient technologies.

  1. Biofilms and mechanics: a review of experimental techniques and findings

    International Nuclear Information System (INIS)

    Gordon, Vernita D; Davis-Fields, Megan; Kovach, Kristin; Rodesney, Christopher A

    2017-01-01

    Biofilms are developmentally-dynamic communities of sessile microbes that adhere to each other and, often, to other structures in their environment. The cohesive mechanical forces binding microbes to each other confer mechanical and structural stability on the biofilm and give rise to biofilm viscoelasticity. The adhesive mechanical forces binding microbes to other structures in their environment can promote biofilm initiation and mechanosensing that leads to changes in biological activity. Thus, physical mechanics is intrinsic to characteristics that distinguish biofilms from free-swimming or free-floating microbes in liquid culture. However, very little is known about the specifics of what mechanical traits characterize different types of biofilms at different stages of development. Even less is known about how mechanical inputs impact microbial biology and how microbes can adjust their mechanical coupling to, and interaction with, their environment. These knowledge gaps arise, in part, from the challenges associated with experimental measurements of microbial and biofilm biomechanics. Here, we review extant experimental techniques and their most-salient findings to date. At the end of this review we indicate areas where significant advances in the state-of-the art are heading. (topical review)

  2. Finite element modelling of cornea mechanics: a review

    Directory of Open Access Journals (Sweden)

    Talisa Mohammad Nejad

    2014-01-01

    Full Text Available The cornea is a transparent tissue in front of the eye that refracts light and facilitates vision. A slight change in the geometry of the cornea remarkably affects the optical power. Because of this sensitivity, biomechanical study of the cornea can reveal much about its performance and function. In vivo and in vitro studies have been conducted to investigate the mechanics of the cornea and determine its characteristics. Numerical techniques such as the finite element method (FEM have been extensively implemented as effective and noninvasive methods for analyzing corneal mechanics and possible disorders. This article reviews the use of FEM for assessing the mechanical behavior of the cornea. Different applications of FEM in corneal disease studies, surgical predictions, impact simulations, and clinical applications have been reviewed. Some suggestions for the future of this type of modeling in the area of corneal mechanics are also discussed.

  3. Procurement strategic analysis of nuclear safety equipment

    International Nuclear Information System (INIS)

    Wu Caixia; Yang Haifeng; Li Xiaoyang; Li Shixin

    2013-01-01

    The nuclear power development plan in China puts forward a challenge on procurement of nuclear safety equipment. Based on the characteristics of the procurement of nuclear safety equipment, requirements are raised for procurement process, including further clarification of equipment technical specification, establishment and improvement of the expert database of the nuclear power industry, adoption of more reasonable evaluation method and establishment of a unified platform for nuclear power plants to procure nuclear safety equipment. This paper makes recommendation of procurement strategy for nuclear power production enterprises from following aspects, making a plan of procurement progress, dividing procurement packages rationally, establishing supplier database through qualification review and implementing classified management, promoting localization process of key equipment continually and further improving the system and mechanism of procurement of nuclear safety equipment. (authors)

  4. Development of a urinary lithiasis localizer mechanism to couple ultrasound and extracorporeal lithotripsy equipment in canine model

    Directory of Open Access Journals (Sweden)

    Enrico Andrade

    2006-10-01

    Full Text Available INTRODUCTION: Due to the evolution of extracorporeal lithotripsy equipment (ESWL and presently, the fact that most part of the equipment does not present ultrasound to localize urinary calculi, a system that allows adapting ultrasound equipment to ESWL equipment was developed, disposing only of fluoroscopy. Thus, this equipment was developed and was tested in urinary stones in canine models, to check its precision in relation to fluoroscopy. METHOD: Seven male dogs were utilized with the introduction, in the bladder through the ureteral route, of chalkstones, with initial localization by fluoroscopy, with a further ultrasound coincidence check localization of the vesical stones, being submitted to ESWL with a 3-hour, 21 days and 60 days follow-up after the procedure. RESULTS: Success of localization in all animals was verified presenting elimination of stones in the first micturitions, after ESWL. No complications were verified in those animals for 60 days. CONCLUSION: We verified that this equipment can lead to an update of the equipment that use only fluoroscopy, increasing in this way, their technical capacity in the treatment of urinary calculi, mainly in cases of non-radiopaque stones.

  5. The African Peer Review Mechanism: The South African Experience ...

    African Journals Online (AJOL)

    This article compares the results of the African Peer Review Mechanism (APRM) report on South Africa with the evaluation done on the same issues by three academics from different health professions. Four areas which closely affect health and health care (democracy and good political governance; economic governance ...

  6. A review of mechanisms underlying anticarcinogenicity by brassica vegetables

    NARCIS (Netherlands)

    Verhoeven, D.T.H.; Verhagen, H.; Goldbohm, R.A.; Brandt, P.A. van den; Poppel, G. van

    1997-01-01

    The mechanisms by which brassica vegetables might decrease the risk of cancer are reviewed in this paper. Brassicas, including all types of cabbages, broccoli, cauliflower and Brussels sprouts, may be protective against cancer due to their relatively high glucosinolate content. Glucosinolates are

  7. Biofilms and mechanics: a review of experimental techniques and findings

    Science.gov (United States)

    Gordon, Vernita D.; Davis-Fields, Megan; Kovach, Kristin; Rodesney, Christopher A.

    2017-06-01

    Biofilms are developmentally-dynamic communities of sessile microbes that adhere to each other and, often, to other structures in their environment. The cohesive mechanical forces binding microbes to each other confer mechanical and structural stability on the biofilm and give rise to biofilm viscoelasticity. The adhesive mechanical forces binding microbes to other structures in their environment can promote biofilm initiation and mechanosensing that leads to changes in biological activity. Thus, physical mechanics is intrinsic to characteristics that distinguish biofilms from free-swimming or free-floating microbes in liquid culture. However, very little is known about the specifics of what mechanical traits characterize different types of biofilms at different stages of development. Even less is known about how mechanical inputs impact microbial biology and how microbes can adjust their mechanical coupling to, and interaction with, their environment. These knowledge gaps arise, in part, from the challenges associated with experimental measurements of microbial and biofilm biomechanics. Here, we review extant experimental techniques and their most-salient findings to date. At the end of this review we indicate areas where significant advances in the state-of-the art are heading.

  8. Social Information Processing Mechanisms and Victimization: A Literature Review.

    Science.gov (United States)

    van Reemst, Lisa; Fischer, Tamar F C; Zwirs, Barbara W C

    2016-01-01

    The aim of the current literature review, which is based on 64 empirical studies, was to assess to what extent mechanisms of the Social Information Processing (SIP) model of Crick and Dodge (1994) are related to victimization. The reviewed studies have provided support for the relation between victimization and several social information processing mechanisms, especially the interpretation of cues and self-efficacy (as part of the response decision). The relationship between victimization and other mechanisms, such as the response generation, was only studied in a few articles. Until now research has often focused on just one step of the model, instead of attempting to measure the associations between multiple mechanisms and victimization in multivariate analyses. Such analyses would be interesting to gain more insight into the SIP model and its relationship with victimization. The few available longitudinal studies show that mechanisms both predict victimization (internal locus of control, negative self-evaluations and less assertive response selection) and are predicted by victimization (hostile attribution of intent and negative evaluations of others). Associations between victimization and SIP mechanisms vary across different types and severity of victimization (stronger in personal and severe victimization), and different populations (stronger among young victims). Practice could focus on these stronger associations and the interpretation of cues. More research is needed however, to investigate whether intervention programs that address SIP mechanisms are suitable for victimization and all relevant populations. © The Author(s) 2014.

  9. Review of Mechanics and Applications of Auxetic Structures

    Directory of Open Access Journals (Sweden)

    Mariam Mir

    2014-01-01

    Full Text Available One of the important mechanical properties of materials is Poisson’s ratio, which is positive for most of the materials. However, certain materials exhibit “auxetic” properties; that is, they have a negative Poisson’s ratio. Thus auxetic and non-auxetic materials exhibit different deformation mechanisms. A specific microscopic structure in the auxetic materials is important for maintaining a negative Poisson’s ratio. Based on their distinct nature auxetic materials execute certain unique properties in contrast to other materials, which are reviewed in this paper. Thus auxetic materials have important applications in the biomedical field which are also a part of this review article. Many auxetic materials have been discovered, fabricated, and synthesized which differ on the basis of structure, scale and deformation mechanism. The different types of auxetic materials such as auxetic cellular solids, microscopic auxetic polymers, molecular auxetic materials, and auxetic composites have been reviewed comprehensively in this paper. Modeling of auxetic structures is of considerable importance and needs appropriate stress strain configurations; thus different aspects of auxetic modeling have also been reviewed. Packing parameters and relative densities are of prime importance in this regard. This review would thus help the researchers in determining and deciding the various aspects of auxetic nature for their products.

  10. Toughening Mechanisms in Nanolayered MAX Phase Ceramics—A Review

    Directory of Open Access Journals (Sweden)

    Xinhua Chen

    2017-03-01

    Full Text Available Advanced engineering and functional ceramics are sensitive to damage cracks, which delay the wide applications of these materials in various fields. Ceramic composites with enhanced fracture toughness may trigger a paradigm for design and application of the brittle components. This paper reviews the toughening mechanisms for the nanolayered MAX phase ceramics. The main toughening mechanisms for these ternary compounds were controlled by particle toughening, phase-transformation toughening and fiber-reinforced toughening, as well as texture toughening. Based on the various toughening mechanisms in MAX phase, models of SiC particles and fibers toughening Ti3SiC2 are established to predict and explain the toughening mechanisms. The modeling work provides insights and guidance to fabricate MAX phase-related composites with optimized microstructures in order to achieve the desired mechanical properties required for harsh application environments.

  11. Resilience in LGB Youths: A Systematic Review of Protection Mechanisms

    Directory of Open Access Journals (Sweden)

    Daniela Fonseca Freitas

    Full Text Available Abstract: Given the mental health disparities among LGB and heterosexual youth, literature has increasingly emphasized the need to identify the mechanisms that promote resilience among sexual minorities. This systematic review sought to answer the question: what are the protection mechanisms against homophobia among LGB youth? Of the 147 references located in the search, 13 studies were analyzed. The identified protection mechanisms were organized by two criteria: specific to sexual orientation or general, and considered to be at the personal, relational and contextual level. Most of the mechanisms revealed to solely promote the positive adjustment in the presence of risk. General protective mechanisms frequently revealed to be more compensatory of the risks than those specific to sexual orientation.

  12. Detoxification Mechanisms of Mercury Toxicity in Plants: A Review

    Directory of Open Access Journals (Sweden)

    Shilpa Shrivastava

    2015-12-01

    Full Text Available Mercury is one of the most toxic heavy metals present in the earth’s crust. It has been considered as environmental pollutant because of its potent toxicity to plants and humans. In this review, we discuss mercury toxicity responses on plant metabolism and its detoxification mechanism by phytochelatins and antioxidant enzymes. Some light is also shed on selenium antagonistic study with mercury. Due to its potential toxicity, it has attracted attention in fields of soil science and plant nutrition. Mercury has harmful toxic effects on the molecular and physiobiochemical behavior of plants. Mostly research work has been done on seed germination, and shoot, root, and leaf morphology. Enzyme responses with respect to mercury as a result Hg accumulated in food chain is also reviewed here. Hence, this review may provide a compiled data for other researches in this direction, to provide a better mechanism or details about mercury’s noxious effect in the ecosystem.

  13. Statistical analysis of the behaviour of the mechanical equipment of EDFs power plants - evaluation of the availability and safety of thermal and nuclear units

    International Nuclear Information System (INIS)

    Procaccia, H.; Brillon, A.; Cravero, M.; Lucenet, G.

    1975-01-01

    The investigation and research directorate of EDF has undertaken a statistical analysis of the behaviour of large mechanical equipment at conventional power stations during the ten years following the operating reports of these stations. It has thus been possible to determine the intrinsic reliability, the failure rate, the mean repair time, and the mean good operating time of feed water reheating points, power turbines, pumps and boilers of the various EDF plants (125 and 250 MW) leading to a consideration of the feasibility of an extrapolation to present and future plants. Based on these elementary investigation two methods of calculation have been developed. One is used to assess the overall availability of a thermal or nuclear power station based on the knowledge of the failure rates of the equipment, each piece of equipment being associated with an idea of its technical importance in the functioning of the equipment. A numerical application is given for 125 and 250 MW conventional plants. The purpose of the other method is to estimate the operational safety of the safety equipment of nuclear power stations, based on the development of tree diagrams for faults in basic equipment. A numerical example is given for the cooling systems for Phenix and for one of the Super Phenix versions. (author)

  14. The mechanisms underpinning peer support: a literature review.

    Science.gov (United States)

    Watson, Emma

    2017-12-20

    The employment of Peer Support Workers, who themselves have experience of significant emotional distress, can promote recovery at an individual and organisational level. While research examining the benefits of peer support within mental health services continues to grow, an understanding of how, and through what processes, these benefits are reached remains under-developed. To review the published research literature relating to the process of peer support and its underpinning mechanisms to better understand how and why it works. A scoping review of published literature identified studies relating to peer support mechanisms, processes and relationships. Studies were summarised and findings analysed. Five mechanisms were found to underpin peer support relationships (lived experience, love labour, the liminal position of the peer worker, strengths-focussed social and practical support, and the helper role). The identified mechanisms can underpin both the success and difficulties associated with peer support relationships. Further research should review a broader range of literature and clarify how these mechanisms contribute to peer support in different contexts.

  15. Shouldering the load: A review of Joan Stevenson's work on occupational lifting and design evaluation of load carriage equipment.

    Science.gov (United States)

    Costigan, Patrick A; Morin, Evelyn L; Reid, Susan A

    2014-01-01

    In this paper, Dr. Joan Stevenson's work on assessment of the effects of lifting, supporting and transporting loads is reviewed. A defining attribute of this work is the use of objective, biomechanical measures as the basis from which a fuller understanding of all factors affecting worker performance can be obtained, and how such performance should be measured and evaluated. The central objectives and conclusions of Dr. Stevenson's research programs spanning the years from 1985 through 2012 are summarized and discussed in terms of an overall research trajectory. The guiding principle of Dr. Stevenson's work is to reduce the potential harm to which workers are exposed through the development of bona fide occupational standards, a better understanding of risk factors leading to low back pain, and the establishment of an enhanced objective design process for functional load-bearing clothing and equipment.

  16. Biomechanics and mechanical signaling in the ovary: a systematic review.

    Science.gov (United States)

    Shah, Jaimin S; Sabouni, Reem; Cayton Vaught, Kamaria C; Owen, Carter M; Albertini, David F; Segars, James H

    2018-04-24

    Mammalian oogenesis and folliculogenesis share a dynamic connection that is critical for gamete development. For maintenance of quiescence or follicular activation, follicles must respond to soluble signals (growth factors and hormones) and physical stresses, including mechanical forces and osmotic shifts. Likewise, mechanical processes are involved in cortical tension and cell polarity in oocytes. Our objective was to examine the contribution and influence of biomechanical signaling in female mammalian gametogenesis. We performed a systematic review to assess and summarize the effects of mechanical signaling and mechanotransduction in oocyte maturation and folliculogenesis and to explore possible clinical applications. The review identified 2568 publications of which 122 met the inclusion criteria. The integration of mechanical and cell signaling pathways in gametogenesis is complex. Follicular activation or quiescence are influenced by mechanical signaling through the Hippo and Akt pathways involving the yes-associated protein (YAP), transcriptional coactivator with PDZ-binding motif (TAZ), phosphatase and tensin homolog deleted from chromosome 10 (PTEN) gene, the mammalian target of rapamycin (mTOR), and forkhead box O3 (FOXO3) gene. There is overwhelming evidence that mechanical signaling plays a crucial role in development of the ovary, follicle, and oocyte throughout gametogenesis. Emerging data suggest the complexities of mechanotransduction and the biomechanics of oocytes and follicles are integral to understanding of primary ovarian insufficiency, ovarian aging, polycystic ovary syndrome, and applications of fertility preservation.

  17. Portraying mechanics of plant growth promoting rhizobacteria (PGPR: A review

    Directory of Open Access Journals (Sweden)

    Dweipayan Goswami

    2016-12-01

    Full Text Available Population growth and increase in food requirement is the global problem. It is inevitable to introduce new practices that help to increase agricultural productivity. Use of plant growth promoting rhizobacteria (PGPR has shown potentials to be a promising technique in the practice of sustainable agriculture. A group of natural soil microbial flora acquire dwelling in the rhizosphere and on the surface of the plant roots which impose beneficial effect on the overall well-being of the plant are categorized as PGPR. Researchers are actively involved in understanding plant growth promoting mechanics employed by PGPR. Broadly, these are divided into direct and indirect mechanics. Any mechanism that directly enhances plant growth either by providing nutrients or by producing growth regulators are portrayed as direct mechanics. Whereas, any mechanisms that protects plant from acquiring infections (biotic stress or helps plant to grow healthily under environmental stresses (abiotic stress are considered indirect mechanics. This review is focused to describe cogent mechanics employed by PGPR that assists plant to sustain healthy growth. Also, we emphasized on the PGPR-based products which have been commercially developed exploiting these mechanics of PGPR.

  18. Review of student difficulties in upper-level quantum mechanics

    Directory of Open Access Journals (Sweden)

    Chandralekha Singh

    2015-09-01

    Full Text Available [This paper is part of the Focused Collection on Upper Division Physics Courses.] Learning advanced physics, in general, is challenging not only due to the increased mathematical sophistication but also because one must continue to build on all of the prior knowledge acquired at the introductory and intermediate levels. In addition, learning quantum mechanics can be especially challenging because the paradigms of classical mechanics and quantum mechanics are very different. Here, we review research on student reasoning difficulties in learning upper-level quantum mechanics and research on students’ problem-solving and metacognitive skills in these courses. Some of these studies were multiuniversity investigations. The investigations suggest that there is large diversity in student performance in upper-level quantum mechanics regardless of the university, textbook, or instructor, and many students in these courses have not acquired a functional understanding of the fundamental concepts. The nature of reasoning difficulties in learning quantum mechanics is analogous to reasoning difficulties found via research in introductory physics courses. The reasoning difficulties were often due to overgeneralizations of concepts learned in one context to another context where they are not directly applicable. Reasoning difficulties in distinguishing between closely related concepts and in making sense of the formalism of quantum mechanics were common. We conclude with a brief summary of the research-based approaches that take advantage of research on student difficulties in order to improve teaching and learning of quantum mechanics.

  19. A novel mechanical design of broken rope protection device for enhancing the safety performances of overhead manned equipment in coal mine

    Directory of Open Access Journals (Sweden)

    Xiaoguang Zhang

    2015-08-01

    Full Text Available A novel mechanical design of the broken rope protection device is proposed to enhance the safety performances of the overhead manned equipment. According to the operating characteristics and functional requirements of the overhead manned equipment, a three-dimensional mechanical model of the broken rope protection device was redesigned. Based on the known parameters of the mechanical model, the stress and strength of the main components are readjusted using the statics characteristics of finite element analysis. To ensure the reliability of the control system of the broken rope protection device, the process of people’s falling, the response performance of the tension sensor, and the signal extraction of the broken rope are analyzed under different loading and unloading speeds. The working principle of the broken rope protection device is expounded in detail. The experimental results showed that better effect is obtained by the new broken rope protection device, which is characterized by good durability, low investment, and high reliability.

  20. Learning Team Review 2016-0001: Installing Outlets for Programmatic Equipment

    Energy Technology Data Exchange (ETDEWEB)

    Dunwoody, John Tyler [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Obrey, Kimberly Ann [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Bridgewater, Jon S. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Griego, Frank X. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Brenner, Andrew Karl [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Lopez, Ted T. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Henderson, Kevin C. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Gordon, Lloyd Baumgardner [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Blumberg, Paul A. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Wilburn, Dianne Williams [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-09-08

    The purpose of a Learning Team is to transfer and communicate the information into operational feedback and improvement. We want to pay attention to the small things that go wrong because they are often early warning signals and may provide insight into the health of the whole system. An ESR was placed in the October of 2015 to move/install a number of 120V and 208V outlets in 455-104B to support programmatic furnace needs. Electrical design review was completed for ESR 22217 on February 22, 2016 and a Design Change Form completed describing the modification needed as: demolish 1 existing receptacle and circuit leaving conduit and jbox for use to install new receptacle and 5 new receptacles/circuits are required and one existing receptacle is to be relocated, listed under FSR 149229. The FSR scope of work was written:: Please have the Electricians come out to perform demolition (1ea.), installation (6ea.)& relocation (1ea.) of receptacles / circuits. ESR 22217 & DCF-16-35-0455-1281 is in place for this work. Coordinate final receptacle locations with Laboratory Resident. Contact John Dunwoody or O-MC for this information. WO# 545580-01 was signed on April 20, 2016.: Electricians to perform demolition, installation, & relocation of receptacles / circuits PER attached DCF-16-0455-1281-SK-1.

  1. Myositis non-inflammatory mechanisms: An up-dated review.

    Science.gov (United States)

    Manole, Emilia; Bastian, Alexandra E; Butoianu, Niculina; Goebel, Hans H

    2017-01-01

    Idiopathic inflammatory myopathies (IIM) represent a heterogeneous group of rare muscular diseases, with no clearly known causes. IIM frequently have an incomplete response to treatment due to the difficulty in distinguishing between IIM forms, and due to neglect their non-inflammatory causes. Important data concerning non-immune mechanisms in IIM pathology have been recently accumulated. There is a correlation between inflammatory and non-inflammatory mechanisms, but their involvement in IIM pathogenesis is still unknown. Here we review some of the most important data regarding the non-immune IIM pathology, highlighting possible future therapeutic targets: endoplasmic reticulum stress, ATP metabolism, ROS generation, autophagy, and microRNAs disturbances.

  2. Mental Models for Mechanical Comprehension. A Review of Literature.

    Science.gov (United States)

    1986-06-01

    models, constructionism , infinirm t - ,’a f.mrfn.~ gl 19 ABSTRACT (Continue on reverse if necessary and identify by block number) 4 This literature...review describes the recent research on mental models of mechanical comprehension. Three methodological approaches ( constructionism , information...things for a teacher to do to aid students’ attempts at understanding the forces involved: 1. Prepare an engaging social context. 2. Juxtapose several

  3. Underlying mechanisms of transient luminous events: a review

    OpenAIRE

    V. V. Surkov; M. Hayakawa

    2012-01-01

    Transient luminous events (TLEs) occasionally observed above a strong thunderstorm system have been the subject of a great deal of research during recent years. The main goal of this review is to introduce readers to recent theories of electrodynamics processes associated with TLEs. We examine the simplest versions of these theories in order to make their physics as transparent as possible. The study is begun with the conventional mechanism for air breakdown at stratospheric...

  4. Metal Additive Manufacturing: A Review of Mechanical Properties

    Science.gov (United States)

    Lewandowski, John J.; Seifi, Mohsen

    2016-07-01

    This article reviews published data on the mechanical properties of additively manufactured metallic materials. The additive manufacturing techniques utilized to generate samples covered in this review include powder bed fusion (e.g., EBM, SLM, DMLS) and directed energy deposition (e.g., LENS, EBF3). Although only a limited number of metallic alloy systems are currently available for additive manufacturing (e.g., Ti-6Al-4V, TiAl, stainless steel, Inconel 625/718, and Al-Si-10Mg), the bulk of the published mechanical properties information has been generated on Ti-6Al-4V. However, summary tables for published mechanical properties and/or key figures are included for each of the alloys listed above, grouped by the additive technique used to generate the data. Published values for mechanical properties obtained from hardness, tension/compression, fracture toughness, fatigue crack growth, and high cycle fatigue are included for as-built, heat-treated, and/or HIP conditions, when available. The effects of test orientation/build direction on properties, when available, are also provided, along with discussion of the potential source(s) (e.g., texture, microstructure changes, defects) of anisotropy in properties. Recommendations for additional work are also provided.

  5. Exercise-induced rhabdomyolysis mechanisms and prevention: A literature review

    Directory of Open Access Journals (Sweden)

    Jooyoung Kim

    2016-09-01

    Full Text Available Exercise-induced rhabdomyolysis (exRML, a pathophysiological condition of skeletal muscle cell damage that may cause acute renal failure and in some cases death. Increased Ca2+ level in cells along with functional degradation of cell signaling system and cell matrix have been suggested as the major pathological mechanisms associated with exRML. The onset of exRML may be exhibited in athletes as well as in general population. Previous studies have reported that possible causes of exRML were associated with excessive eccentric contractions in high temperature, abnormal electrolytes balance, and nutritional deficiencies possible genetic defects. However, the underlying mechanisms of exRML have not been clearly established among health professionals or sports medicine personnel. Therefore, we reviewed the possible mechanisms and correlated prevention of exRML, while providing useful and practical information for the athlete and general exercising population.

  6. Neural mechanisms underlying morphine withdrawal in addicted patients: a review

    Directory of Open Access Journals (Sweden)

    Nima Babhadiashar

    2015-06-01

    Full Text Available Morphine is one of the most potent alkaloid in opium, which has substantial medical uses and needs and it is the first active principle purified from herbal source. Morphine has commonly been used for relief of moderate to severe pain as it acts directly on the central nervous system; nonetheless, its chronic abuse increases tolerance and physical dependence, which is commonly known as opiate addiction. Morphine withdrawal syndrome is physiological and behavioral symptoms that stem from prolonged exposure to morphine. A majority of brain regions are hypofunctional over prolonged abstinence and acute morphine withdrawal. Furthermore, several neural mechanisms are likely to contribute to morphine withdrawal. The present review summarizes the literature pertaining to neural mechanisms underlying morphine withdrawal. Despite the fact that morphine withdrawal is a complex process, it is suggested that neural mechanisms play key roles in morphine withdrawal.

  7. Bioinspired Bouligand cellulose nanocrystal composites: a review of mechanical properties

    Science.gov (United States)

    Natarajan, Bharath; Gilman, Jeffrey W.

    2017-12-01

    The twisted plywood, or Bouligand, structure is the most commonly observed microstructural motif in natural materials that possess high mechanical strength and toughness, such as that found in bone and the mantis shrimp dactyl club. These materials are isotropically toughened by a low volume fraction of soft, energy-dissipating polymer and by the Bouligand structure itself, through shear wave filtering and crack twisting, deflection and arrest. Cellulose nanocrystals (CNCs) are excellent candidates for the bottom-up fabrication of these structures, as they naturally self-assemble into `chiral nematic' films when cast from solutions and possess outstanding mechanical properties. In this article, we present a review of the fabrication techniques and the corresponding mechanical properties of Bouligand biomimetic CNC nanocomposites, while drawing comparison to the performance standards set by tough natural composite materials. This article is part of a discussion meeting issue `New horizons for cellulose nanotechnology'.

  8. Bio-mimetic mechanisms of natural hierarchical materials: a review.

    Science.gov (United States)

    Chen, Qiang; Pugno, Nicola M

    2013-03-01

    Natural selection and evolution develop a huge amount of biological materials in different environments (e.g. lotus in water and opuntia in desert). These biological materials possess many inspiring properties, which hint scientists and engineers to find some useful clues to create new materials or update the existing ones. In this review, we highlight some well-studied (e.g. nacre shell) and newly-studied (e.g. turtle shell) natural materials, and summarize their hierarchical structures and mechanisms behind their mechanical properties, from animals to plants. These fascinating mechanisms suggest to researchers to investigate natural materials deeply and broadly, and to design or fabricate new bio-inspired materials to serve our life. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Mississippi Curriculum Framework for Diesel Equipment Technology (CIP: 47.0605--Diesel Engine Mechanic & Repairer). Postsecondary Programs.

    Science.gov (United States)

    Mississippi Research and Curriculum Unit for Vocational and Technical Education, State College.

    This document, which is intended for use by community and junior colleges throughout Mississippi, contains curriculum frameworks for the course sequences in the diesel equipment technology programs cluster. Presented in the introductory section are a description of the program and suggested course sequence. Section I lists baseline competencies,…

  10. Fire protection in nuclear power plants. Pt. 3. Fire protection for mechanical and electrotechnical equipment and components

    International Nuclear Information System (INIS)

    1994-01-01

    The KTA rule applies to LWRs and defines requirements to be met for fire protection of equipment and installations of the safety system, and all safety-relevant systems, and of those operating systems that under the effect of fire, may cause improper functioning of safety system components. (orig./HP) [de

  11. Equipment qualification research program: program plan

    International Nuclear Information System (INIS)

    Dong, R.G.; Smith, P.D.

    1982-01-01

    The Lawrence Livermore National Laboratory (LLNL) under the sponsorship of the US Nuclear Regulatory Commission (NRC) has developed this program plan for research in equipment qualification (EQA). In this report the research program which will be executed in accordance with this plan will be referred to as the Equipment Qualification Research Program (EQRP). Covered are electrical and mechanical equipment under the conditions described in the OBJECTIVE section of this report. The EQRP has two phases; Phase I is primarily to produce early results and to develop information for Phase II. Phase I will last 18 months and consists of six projects. The first project is program management. The second project is responsible for in-depth evaluation and review of EQ issues and EQ processes. The third project is responsible for detailed planning to initiate Phase II. The remaining three projects address specific equipment; i.e., valves, electrical equipment, and a pump

  12. Summary review of rock mechanics workshop on radioactive waste disposal

    International Nuclear Information System (INIS)

    Carter, N.L.; Goodman, R.E.; Merrill, R.H.

    1977-01-01

    Presentations, critiques and recommendations for the disposal of commercial radioactive waste based upon an analysis of the information presented at the Rock Mechanics Review/Workshop, Denver, Colorado, December 16-17, 1976 are summarized. The workshop, comprised of both formal and informal sessions, with about 50 participants, was hosted by RE/SPEC Inc. and Dr. Paul F. Gnirk, President and was sponsored by the Office of Waste Isolation (OWI), led by Dr. William C. McClain. The panel of reviewers, responsible for this report, consisted of Neville L. Carter, Richard E. Goodman, and Robert H. Merrill. These panel members were selected not only on the basis of their experience in various aspects of Rock Mechanics and Mining Engineering but also because they have had no previous active participation in problems concerning disposal of radioactive waste. By way of a general comment, the review panel was very favorably impressed with the Rock Mechanics research efforts, supported by OWI, on this problem and with the level of technical competence of those carrying out the research. Despite the rather preliminary nature of the results presented and the youth of the program itself, it is clear that the essential ingredients for a successful program are at hand, especially as regards disposal in natural salt formations. These include laboratory studies of appropriate rock deformation, numerical analyses of thermal and mechanical stresses around openings, and in situ field tests. We shall comment on each of these three major areas in turn. We shall then offer recommendations for their improvement, and, finally, we shall make more general recommendations for future considerations of the OWI radioactive waste disposal program

  13. Yogurt and Cardiometabolic Diseases: A Critical Review of Potential Mechanisms.

    Science.gov (United States)

    Fernandez, Melissa Anne; Panahi, Shirin; Daniel, Noémie; Tremblay, Angelo; Marette, André

    2017-11-01

    Associations between yogurt intake and risk of diet-related cardiometabolic diseases (CMDs) have been the subject of recent research in epidemiologic nutrition. A healthy dietary pattern has been identified as a pillar for the prevention of weight gain and CMDs. Epidemiologic studies suggest that yogurt consumption is linked to healthy dietary patterns, lifestyles, and reduced risk of CMDs, particularly type 2 diabetes. However, to our knowledge, few to no randomized controlled trials have investigated yogurt intake in relation to cardiometabolic clinical outcomes. Furthermore, there has been little attempt to clarify the mechanisms that underlie the potential beneficial effects of yogurt consumption on CMDs. Yogurt is a nutrient-dense dairy food and has been suggested to reduce weight gain and prevent CMDs by contributing to intakes of protein, calcium, bioactive lipids, and several other micronutrients. In addition, fermentation with bacterial strains generates bioactive peptides, resulting in a potentially greater beneficial effect of yogurt on metabolic health than nonfermented dairy products such as milk. To date, there is little concrete evidence that the mechanisms proposed in observational studies to explain positive results of yogurt on CMDs or parameters are valid. Many proposed mechanisms are based on assumptions that commercial yogurts contain strain-specific probiotics, that viable yogurt cultures are present in adequate quantities, and that yogurt provides a minimum threshold dose of nutrients or bioactive components capable of exerting a physiologic effect. Therefore, the primary objective of this review is to investigate the plausibility of potential mechanisms commonly cited in the literature in order to shed light on the inverse associations reported between yogurt intake and various cardiometabolic health parameters that are related to its nutrient profile, bacterial constituents, and food matrix. This article reviews current gaps and challenges

  14. Underlying mechanisms of transient luminous events: a review

    Directory of Open Access Journals (Sweden)

    V. V. Surkov

    2012-08-01

    Full Text Available Transient luminous events (TLEs occasionally observed above a strong thunderstorm system have been the subject of a great deal of research during recent years. The main goal of this review is to introduce readers to recent theories of electrodynamics processes associated with TLEs. We examine the simplest versions of these theories in order to make their physics as transparent as possible. The study is begun with the conventional mechanism for air breakdown at stratospheric and mesospheric altitudes. An electron impact ionization and dissociative attachment to neutrals are discussed. A streamer size and mobility of electrons as a function of altitude in the atmosphere are estimated on the basis of similarity law. An alternative mechanism of air breakdown, runaway electron mechanism, is discussed. In this section we focus on a runaway breakdown field, characteristic length to increase avalanche of runaway electrons and on the role played by fast seed electrons in generation of the runaway breakdown. An effect of thunderclouds charge distribution on initiation of blue jets and gigantic jets is examined. A model in which the blue jet is treated as upward-propagating positive leader with a streamer zone/corona on the top is discussed. Sprite models based on streamer-like mechanism of air breakdown in the presence of atmospheric conductivity are reviewed. To analyze conditions for sprite generation, thunderstorm electric field arising just after positive cloud-to-ground stroke is compared with the thresholds for propagation of positively/negatively charged streamers and with runway breakdown. Our own estimate of tendril's length at the bottom of sprite is obtained to demonstrate that the runaway breakdown can trigger the streamer formation. In conclusion we discuss physical mechanisms of VLF (very low frequency and ELF (extremely low frequency phenomena associated with sprites.

  15. Implementation and adoption of mechanical patient lift equipment in the hospital setting: The importance of organizational and cultural factors.

    Science.gov (United States)

    Schoenfisch, Ashley L; Myers, Douglas J; Pompeii, Lisa A; Lipscomb, Hester J

    2011-12-01

    Work focused on understanding implementation and adoption of interventions designed to prevent patient-handling injuries in the hospital setting is lacking in the injury literature and may be more insightful than more traditional evaluation measures. Data from focus groups with health care workers were used to describe barriers and promoters of the adoption of patient lift equipment and a shift to a "minimal-manual lift environment" at two affiliated hospitals. Several factors influencing the adoption of the lift equipment and patient-handling policy were noted: time, knowledge/ability, staffing, patient characteristics, and organizational and cultural aspects of work. The adoption process was complex, and considerable variability by hospital and across units was observed. The use of qualitative data can enhance the understanding of factors that influence implementation and adoption of interventions designed to prevent patient-handling injuries among health care workers. Copyright © 2011 Wiley Periodicals, Inc.

  16. Mini-review: Molecular mechanisms of antifouling compounds

    KAUST Repository

    Qian, Pei-Yuan

    2013-04-01

    Various antifouling (AF) coatings have been developed to protect submerged surfaces by deterring the settlement of the colonizing stages of fouling organisms. A review of the literature shows that effective AF compounds with specific targets are ones often considered non-toxic. Such compounds act variously on ion channels, quorum sensing systems, neurotransmitters, production/release of adhesive, and specific enzymes that regulate energy production or primary metabolism. In contrast, AF compounds with general targets may or may not act through toxic mechanisms. These compounds affect a variety of biological activities including algal photosynthesis, energy production, stress responses, genotoxic damage, immunosuppressed protein expression, oxidation, neurotransmission, surface chemistry, the formation of biofilms, and adhesive production/release. Among all the targets, adhesive production/release is the most common, possibly due to a more extensive research effort in this area. Overall, the specific molecular targets and the molecular mechanisms of most AF compounds have not been identified. Thus, the information available is insufficient to draw firm conclusions about the types of molecular targets to be used as sensitive biomarkers for future design and screening of compounds with AF potential. In this review, the relevant advantages and disadvantages of the molecular tools available for studying the molecular targets of AF compounds are highlighted briefly and the molecular mechanisms of the AF compounds, which are largely a source of speculation in the literature, are discussed. © 2013 Copyright Taylor and Francis Group, LLC.

  17. Capital Equipment Replacement Decisions

    OpenAIRE

    Batterham, Robert L.; Fraser, K.I.

    1995-01-01

    This paper reviews the literature on the optimal replacement of capital equipment, especially farm machinery. It also considers the influence of taxation and capital rationing on replacement decisions. It concludes that special taxation provisions such as accelerated depreciation and investment allowances are unlikely to greatly influence farmers' capital equipment replacement decisions in Australia.

  18. Mechanical characterization of composite materials by optical techniques: A review

    Science.gov (United States)

    Bruno, Luigi

    2018-05-01

    The present review provides an overview of work published in recent years dealing with the mechanical characterization of composite materials performed by optical techniques. The paper emphasizes the strengths derived from the employment of full-field methods when the strain field of an anisotropic material must be evaluated. This is framed in contrast to the use of conventional measurement techniques, which provide single values of the measured quantities unable to offer thorough descriptions of deformation distribution. The review outlines the intensity and articulation of work in this research field to date and its ongoing importance not only in the academy, but also in industrial sectors where composite materials represent a strategic resource for development.

  19. Review of coaxial flow gas core nuclear rocket fluid mechanics

    International Nuclear Information System (INIS)

    Weinstein, H.

    1976-01-01

    In a prematurely aborted attempt to demonstrate the feasibility of using a gas core nuclear reactor as a rocket engine, NASA initiated a number of studies on the relevant fluid mechanics problems. These studies were carried out at NASA laboratories, universities and industrial research laboratories. Because of the relatively sudden termination of most of this work, a unified overview was never presented which demonstrated the accomplishments of the program and pointed out the areas where additional work was required for a full understanding of the cavity flow. This review attempts to fulfill a part of this need in two important areas

  20. [Review: plant polyphenols modulate lipid metabolism and related molecular mechanism].

    Science.gov (United States)

    Dai, Yan-li; Zou, Yu-xiao; Liu, Fan; Li, Hong-zhi

    2015-11-01

    Lipid metabolism disorder is an important risk factor to obesity, hyperlipidemia and type 2 diabetes as well as other chronic metabolic disease. It is also a key target in preventing metabolic syndrome, chronic disease prevention. Plant polyphenol plays an important role in maintaining or improving lipid profile in a variety of ways. including regulating cholesterol absorption, inhibiting synthesis and secretion of triglyceride, and lowering plasma low density lipoprotein oxidation, etc. The purpose of this article is to review the lipid regulation effects of plant polyphenols and its related mechanisms.

  1. Reviews Equipment: Vibration detector Equipment: SPARK Science Learning System PS-2008 Equipment: Pelton wheel water turbine Book: Atomic: The First War of Physics and the Secret History of the Atom Bomb 1939-49 Book: Outliers: The Story of Success Book: T-Minus: The Race to the Moon Equipment: Fridge Rover Equipment: Red Tide School Spectrophotometer Web Watch

    Science.gov (United States)

    2010-03-01

    WE RECOMMEND Vibration detector SEP equipment measures minor tremors in the classroom SPARK Science Learning System PS-2008 Datalogger is easy to use and has lots of added possibilities Atomic: The First War of Physics and the Secret History of the Atom Bomb 1939-49 Book is crammed with the latest on the atom bomb T-Minus: The Race to the Moon Graphic novel depicts the politics as well as the science Fridge Rover Toy car can teach magnetics and energy, and is great fun Red Tide School Spectrophotometer Professional standard equipment for the classroom WORTH A LOOK Pelton wheel water turbine Classroom-sized version of the classic has advantages Outliers: The Story of Success Study of why maths is unpopular is relevant to physics teaching WEB WATCH IOP webcasts are improving but are still not as impressive as Jodrell Bank's Chromoscope website

  2. A Review of Disintegration Mechanisms and Measurement Techniques.

    Science.gov (United States)

    Markl, Daniel; Zeitler, J Axel

    2017-05-01

    Pharmaceutical solid dosage forms (tablets or capsules) are the predominant form to administer active pharmaceutical ingredients (APIs) to the patient. Tablets are typically powder compacts consisting of several different excipients in addition to the API. Excipients are added to a formulation in order to achieve the desired fill weight of a dosage form, to improve the processability or to affect the drug release behaviour in the body. These complex porous systems undergo different mechanisms when they come in contact with physiological fluids. The performance of a drug is primarily influenced by the disintegration and dissolution behaviour of the powder compact. The disintegration process is specifically critical for immediate-release dosage forms. Its mechanisms and the factors impacting disintegration are discussed and methods used to study the disintegration in-situ are presented. This review further summarises mathematical models used to simulate disintegration phenomena and to predict drug release kinetics.

  3. A review of acrylamide toxicity and its mechanism

    Directory of Open Access Journals (Sweden)

    Ehsan Zamani

    2017-05-01

    Full Text Available Acrylamide (AA is an important industrial chemical agent that is mainly used in the production of polymers and copolymers. Recently it has been attention because of its production in the diet at high-temperature (>120 ºC processes such as cooking, frying, toasting, roasting or baking of high carbohydrate foods. According to high exposure to acrylamide, recognition of its toxic effect is necessary. Neurotoxicity, reproductive toxicity and immunotoxicity of AA were observed in several studies. There isn’t a clear mechanism that justifies this toxicity. In this study we reviewed the mechanisms of AA toxicity especially oxidative stress and apoptosis. AA can cause neurotoxicity, reproductive toxicity and genotoxicity on animal models. It showed neurotoxicity in human. We suggested the oxidative stress is the main factor for inducing of acrylamide toxicities. We advised that modifying of food processing methods can be as a good way for decreasing of AA production in foods.

  4. Mechanical behavior and stress effects in hard superconductors: a review

    International Nuclear Information System (INIS)

    Koch, C.C.; Easton, D.S.

    1977-11-01

    The mechanical properties of type II superconducting materials are reviewed as well as the effect of stress on the superconducting properties of these materials. The bcc alloys niobium-titanium and niobium-zirconium exhibit good strength and extensive ductility at room temperature. Mechanical tests on these alloys at 4.2 0 K revealed serrated stress-strain curves, nonlinear elastic effects and reduced ductility. The nonlinear behavior is probably due to twinning and detwinning or a reversible stress-induced martensitic transformation. The brittle A-15 compound superconductors, such as Nb 3 Sn and V 3 Ga, exhibit unusual elastic properties and structural instabilities at cryogenic temperatures. Multifilamentary composites consisting of superconducting filaments in a normal metal matrix are generally used for superconducting devices. The mechanical properties of alloy and compound composites, tapes, as well as composites of niobium carbonitride chemically vapor deposited on high strength carbon fibers are presented. Hysteretic stress-strain behavior in the metal matrix composites produces significant heat generation, an effect which may lead to degradation in the performance of high field magnets. Measurements of the critical current density, J/sub c/, under stress in a magnetic field are reported. Modest stress-reversible degradation in J/sub c/ was observed in niobium-titanium composites, while more serious degradation was found in Nb 3 Sn samples. The importance of mechanical behavior to device performance is discussed

  5. Humidity Sensors Principle, Mechanism, and Fabrication Technologies: A Comprehensive Review

    Science.gov (United States)

    Farahani, Hamid; Wagiran, Rahman; Hamidon, Mohd Nizar

    2014-01-01

    Humidity measurement is one of the most significant issues in various areas of applications such as instrumentation, automated systems, agriculture, climatology and GIS. Numerous sorts of humidity sensors fabricated and developed for industrial and laboratory applications are reviewed and presented in this article. The survey frequently concentrates on the RH sensors based upon their organic and inorganic functional materials, e.g., porous ceramics (semiconductors), polymers, ceramic/polymer and electrolytes, as well as conduction mechanism and fabrication technologies. A significant aim of this review is to provide a distinct categorization pursuant to state of the art humidity sensor types, principles of work, sensing substances, transduction mechanisms, and production technologies. Furthermore, performance characteristics of the different humidity sensors such as electrical and statistical data will be detailed and gives an added value to the report. By comparison of overall prospects of the sensors it was revealed that there are still drawbacks as to efficiency of sensing elements and conduction values. The flexibility offered by thick film and thin film processes either in the preparation of materials or in the choice of shape and size of the sensor structure provides advantages over other technologies. These ceramic sensors show faster response than other types. PMID:24784036

  6. Humidity Sensors Principle, Mechanism, and Fabrication Technologies: A Comprehensive Review

    Directory of Open Access Journals (Sweden)

    Hamid Farahani

    2014-04-01

    Full Text Available Humidity measurement is one of the most significant issues in various areas of applications such as instrumentation, automated systems, agriculture, climatology and GIS. Numerous sorts of humidity sensors fabricated and developed for industrial and laboratory applications are reviewed and presented in this article. The survey frequently concentrates on the RH sensors based upon their organic and inorganic functional materials, e.g., porous ceramics (semiconductors, polymers, ceramic/polymer and electrolytes, as well as conduction mechanism and fabrication technologies. A significant aim of this review is to provide a distinct categorization pursuant to state of the art humidity sensor types, principles of work, sensing substances, transduction mechanisms, and production technologies. Furthermore, performance characteristics of the different humidity sensors such as electrical and statistical data will be detailed and gives an added value to the report. By comparison of overall prospects of the sensors it was revealed that there are still drawbacks as to efficiency of sensing elements and conduction values. The flexibility offered by thick film and thin film processes either in the preparation of materials or in the choice of shape and size of the sensor structure provides advantages over other technologies. These ceramic sensors show faster response than other types.

  7. Mechanisms Involved in Exercise-Induced Cardioprotection: A Systematic Review

    Science.gov (United States)

    Borges, Juliana Pereira; Lessa, Marcos Adriano

    2015-01-01

    Background Acute myocardial infarction is the leading cause of morbidity and mortality worldwide. Furthermore, research has shown that exercise, in addition to reducing cardiovascular risk factors, can also protect the heart against injury due to ischemia and reperfusion through a direct effect on the myocardium. However, the specific mechanism involved in exerciseinduced cardiac preconditioning is still under debate. Objective To perform a systematic review of the studies that have addressed the mechanisms by which aerobic exercise promotes direct cardioprotection against ischemia and reperfusion injury. Methods A search was conducted using MEDLINE, Literatura Latino-Americana e do Caribe de Informação em Ciências da Saúde, and Scientific Electronic Library Online databases. Data were extracted in a standardized manner by two independent researchers, who were responsible for assessing the methodological quality of the studies. Results The search retrieved 78 studies; after evaluating the abstracts, 30 studies were excluded. The manuscripts of the remaining 48 studies were completely read and, of these, 20 were excluded. Finally, 28 studies were included in this systematic review. Conclusion On the basis of the selected studies, the following are potentially involved in the cardioprotective response to exercise: increased heat shock protein production, nitric oxide pathway involvement, increased cardiac antioxidant capacity, improvement in ATP-dependent potassium channel function, and opioid system activation. Despite all the previous investigations, further research is still necessary to obtain more consistent conclusions. PMID:25830711

  8. Assessment of the TRANSREC-350 mechanical recovery capacity of the oil spill response equipment in Prince William Sound

    International Nuclear Information System (INIS)

    Provant, S.G.

    1992-01-01

    Studies were conducted to determine the compliance of oil spill response equipment in Prince William Sound, Alaska, to state standards. Data on the observed performance of the Framo TRANSREC skimmer, which represents a large portion of the initial response skimming capability of the Sound's equipment, were obtained from Norwegian experience. The results of the analysis are based on the level of performance expected from well-trained skimmer crews responding to a 300,000 bbl spill under the worst average weather conditions over a 72-h period. Certain assumptions are made about volumes of evaporation and decanting. Results indicate that the volume of oil expected to be recovered would be 188,900 bbl, which would expand via emulsion formation to 303,000 bbl. In addition, a volume of free water would be taken in with the emulsion, which would be reduced by decanting. The overall storage capacity needed would then be 382,300 bbl. With the present available configuration of skimmers and barges, the maximum available storage capacity is 370,000 bbl. Skimmer capability can be maximized by matching storage capacity to recovery capability or by developing and demonstrating a capability to offload the recovered oil effectively such that transfer operations do not materially affect recovery operations. Recommendations are made for spill response organizations to improve their operations. 4 refs., 9 figs

  9. Fracture Mechanics Analyses for Interface Crack Problems - A Review

    Science.gov (United States)

    Krueger, Ronald; Shivakumar, Kunigal; Raju, Ivatury S.

    2013-01-01

    Recent developments in fracture mechanics analyses of the interfacial crack problem are reviewed. The intent of the review is to renew the awareness of the oscillatory singularity at the crack tip of a bimaterial interface and the problems that occur when calculating mode mixity using numerical methods such as the finite element method in conjunction with the virtual crack closure technique. Established approaches to overcome the nonconvergence issue of the individual mode strain energy release rates are reviewed. In the recent literature many attempts to overcome the nonconvergence issue have been developed. Among the many approaches found only a few methods hold the promise of providing practical solutions. These are the resin interlayer method, the method that chooses the crack tip element size greater than the oscillation zone, the crack tip element method that is based on plate theory and the crack surface displacement extrapolation method. Each of the methods is validated on a very limited set of simple interface crack problems. However, their utility for a wide range of interfacial crack problems is yet to be established.

  10. Mechanical valve obstruction: Review of diagnostic and treatment strategies

    Science.gov (United States)

    Salamon, Jason; Munoz-Mendoza, Jerson; Liebelt, Jared J; Taub, Cynthia C

    2015-01-01

    Prosthetic valve obstruction (PVO) is a rare but feared complication of mechanical valve replacement. Diagnostic evaluation should focus on differentiating prosthetic valve thrombosis (PVT) from pannus formation, as their treatment options differ. History of sub-optimal anti-coagulation and post-op time course to development of PVO are useful clinical characteristics in differentiating thrombus from pannus formation. Treatment of PVT is influenced by the patient’s symptoms, valve location, degree of obstruction and thrombus size and may include thrombolysis or surgical intervention. Alternatively, pannus formation requires surgical intervention. The purpose of this article is to review the pathophysiology, epidemiology, diagnostic approach and treatment options for aortic and mitral valve PVO. PMID:26730292

  11. Seismic and dynamic qualification of safety-related electrical and mechanical equipment in operating nuclear power plants: development of a method to generate generic floor-response spectra

    International Nuclear Information System (INIS)

    Curreri, J.; Costantino, C.; Subudhi, M.; Reich, M.

    1983-09-01

    Generic floor response spectra were developed for use in the qualification of electrical and mechanical equipment in operating nuclear power plants. The characteristics of 1000 floor response spectra were studied to determine the generic spectra. The procedure developed uses as much or as little information that currently exists at the plant relating to the question of equipment qualification. The general approach was to study the effects on the dynamic characteristics of each of the elements in the chain of events that goes between the loads and the responses. This includes the loads, the soils and the structures. A free-field earthquake response spectra was used to generate horizontal earthquake time histories. The excitation was applied through the soil and into the various structures to produce responses in equipment. An entire range of soil conditions was used with each structure. Actual PWR and BWR - Mark I structural models were used. For each model, the stiffness properties were varied, with the same mass, so as to extend the fundamental base structure natural frequency from 2 cps to 36 cps. The natural frequencies of the structures were varied to obtain maximum response conditions. The actual properties were first used to locate the natural frequencies. The stiffness properties were than varied, with the same mass, to extend the range of the fundamental base structure natural frequency. The intention was to have the coupled structural material frequencies in the vicinity of the peak amplitude frequency content of the excitation spectrum. Particular attention was therefore given to the frequency band between 2 Hz and 4 Hz. A horizontal generic floor response spectra is proposed for the top level of a generic structure. Reduction factors are applied to the peak acceleration for equipment at lower levels

  12. Epoxy Resin Based Composites, Mechanical and Tribological Properties: A Review

    Directory of Open Access Journals (Sweden)

    S.A. Bello

    2015-12-01

    Full Text Available High fuel consumption by automobile and aerospace vehicles built from legacy alloys has been a great challenge to global design and material engineers. This has called for researches into material development for the production of lighter materials of the same or even superior mechanical properties to the existing materials in this area of applications. This forms a part of efforts to achieve the global vision 2025 i.e to reduce the fuel consumption by automobile and aerospace vehicles by at least 75 %. Many researchers have identified advanced composites as suitable materials in this regard. Among the common matrices used for the development of advanced composites, epoxy resin has attained a dominance among its counterparts because of its excellent properties including chemical, thermal and electrical resistance properties, mechanical properties and dimensional stability. This review is a reflection of the extensive study on the currently ongoing research aimed at development of epoxy resin hybrid nanocomposites for engineering applications. In this paper, brief explanation has been given to different terms related to the research work and also, some previous works (in accordance with materials within authors’ reach in the area of the ongoing research have been reported.

  13. A review of NOx formation mechanisms in recovery furnaces

    International Nuclear Information System (INIS)

    Nichols, K.M.; Thompson, L.M.; Empie, H.J.

    1993-01-01

    Review of NOx formation studies shows that NO forms in recovery furnaces primarily by two independent mechanisms, thermal and fuel. Thermal NO formation is extremely temperature-sensitive. However, theoretical predictions indicate that recovery furnace temperatures are not high enough to form significant thermal NO. Fuel NO formation is less temperature-sensitive, and is related to fuel nitrogen content. Black liquors are shown to contain 0.05 to 0.24 weight percent fuel nitrogen. Conversion of just 20% of this would yield approximately 25-120 ppm NOx (at 8% 0 2 ) in the flue gas, enough to represent the majority of the total NOx. Data from operating recovery furnaces show NOx emissions ranging from near zero to over 100 ppm at 8% 0 2 . An apparent increase in recovery furnace NOx emissions was observed with increasing solids. This increase is much less than predicted by thermal NO formation theory, indicating that other NO formation/destruction mechanisms, such as fuel NO formation, are important. No data are available to show the relative importance of thermal and fuel NO to total NOx during black liquor combustion

  14. Review: Bioenergetic Fields and Their Biologic Effects Mechanism

    Directory of Open Access Journals (Sweden)

    Zahra Movaffaghi

    2007-04-01

    Full Text Available As interests in complementary and alternative medicine grows, the scientists are looking forward in researches which determine the mechanisms in which they exert their effectiveness. Some of these modalities like Yoga, Acupuncture, and especially other bio-field therapies such as none contact therapeutic touch, affects the bio-field which spreads throughout the body and into the space around it. According to physic’s law, when electricity flows throw the living tissues, like what happens in our heart and brain, biomagnetic fields are being induced in the surrounding space. Beside that moving charges like ions and free radicals which finally produce electromagnetic fields. Using very sensitive magnetometers, biomagnetic fields have been detected and get amplified up to 1000 times by meditation. This phenomenon could be the basis for most of most complementaty therapeutic approaches like therapeutic touch. On the other hand the electrical, magnetic and bio-magnetic fields have a well known application in conventional medicine. Modern research about bio-magnetism and magneto-biology suggests that in term of both aspects, the effects and the mechanisms for all the different looking modalities used in conventional medicine and complementary medicine which have commons in their fundamentals. This article reviews some of the recent works on biological effects of natural or artificial electromagnetic fields.

  15. Mississippi Curriculum Framework for Diesel Equipment Repair & Service (Program CIP: 47.0605--Diesel Engine Mechanic & Repairer). Secondary Programs.

    Science.gov (United States)

    Mississippi Research and Curriculum Unit for Vocational and Technical Education, State College.

    This document, which reflects Mississippi's statutory requirement that instructional programs be based on core curricula and performance-based assessment, contains outlines of the instructional units required in local instructional management plans and daily lesson plans for diesel engine mechanics I and II. Presented first are a program…

  16. Underlying Mechanisms of Tinnitus: Review and Clinical Implications

    Science.gov (United States)

    Henry, James A.; Roberts, Larry E.; Caspary, Donald M.; Theodoroff, Sarah M.; Salvi, Richard J.

    2016-01-01

    Background The study of tinnitus mechanisms has increased tenfold in the last decade. The common denominator for all of these studies is the goal of elucidating the underlying neural mechanisms of tinnitus with the ultimate purpose of finding a cure. While these basic science findings may not be immediately applicable to the clinician who works directly with patients to assist them in managing their reactions to tinnitus, a clear understanding of these findings is needed to develop the most effective procedures for alleviating tinnitus. Purpose The goal of this review is to provide audiologists and other health-care professionals with a basic understanding of the neurophysiological changes in the auditory system likely to be responsible for tinnitus. Results It is increasingly clear that tinnitus is a pathology involving neuroplastic changes in central auditory structures that take place when the brain is deprived of its normal input by pathology in the cochlea. Cochlear pathology is not always expressed in the audiogram but may be detected by more sensitive measures. Neural changes can occur at the level of synapses between inner hair cells and the auditory nerve and within multiple levels of the central auditory pathway. Long-term maintenance of tinnitus is likely a function of a complex network of structures involving central auditory and nonauditory systems. Conclusions Patients often have expectations that a treatment exists to cure their tinnitus. They should be made aware that research is increasing to discover such a cure and that their reactions to tinnitus can be mitigated through the use of evidence-based behavioral interventions. PMID:24622858

  17. Plant effects on soil denitrification - a review of potential mechanisms

    Science.gov (United States)

    Malique, Francois; Butterbach-Bahl, Klaus; Dannenmann, Michael

    2017-04-01

    Denitrification is a microbial process occurring in soils, both producing and consuming the potent greenhouse gas nitrous oxide (NO), competing for nitrate with plants and hydrological leaching pathways, removing nutrients and reactive nitrogen from the biosphere, and closing the global nitrogen cycle. Despite its obvious importance, denitrification remained among the least well quantified biogeochemical processes in soils. This is due to enormous methodological difficulties involved in the direct quantification of soil microbial denitrification rates (mainly with regard to the terminal product N2) and the denitrification nitrogen gas product ratios (NO:N2O:N2), Plants may affect denitrification through a myriad of mechanisms such as e.g., competition for nitrate and water, through oxygen consumption, by regulating litter quality and changing soil pH, and via the exudation of labile carbon or secondary plant compounds involved in shaping the rhizospheric microbial community. However, plant effects on denitrification so far hardly were quantified so that the actual extent of plant control on denitrification is largely unknown. Here, we summarize the current knowledge on mechanisms how plants can affect denitrification rates and N gas product ratios in soils at temporal scales from hours to days and years. We review earlier research to quantify plant effects on denitrification as well as critically discuss the limited methods currently available to quantify plant-soil-denitrifier interactions. Finally, we provide pointers to use plants as tools to manage denitrification, e.g. to improve N use efficiency in agricultural ecosystems and to minimize soil nitrous oxide emissions.

  18. The importance of social networks in their association to drug equipment sharing among injection drug users: a review.

    Science.gov (United States)

    De, Prithwish; Cox, Joseph; Boivin, Jean-François; Platt, Robert W; Jolly, Ann M

    2007-11-01

    To examine the scientific evidence regarding the association between characteristics of social networks of injection drug users (IDUs) and the sharing of drug injection equipment. A search was performed on MEDLINE, EMBASE, BIOSIS, Current Contents, PsycINFO databases and other sources to identify published studies on social networks of IDUs. Papers were selected based on their examination of social network factors in relation to the sharing of syringes and drug preparation equipment (e.g. containers, filters, water). Additional relevant papers were found from the reference list of identified articles. Network correlates of drug equipment sharing are multi-factorial and include structural factors (network size, density, position, turnover), compositional factors (network member characteristics, role and quality of relationships with members) and behavioural factors (injecting norms, patterns of drug use, severity of drug addiction). Factors appear to be related differentially to equipment sharing. Social network characteristics are associated with drug injection risk behaviours and should be considered alongside personal risk behaviours in prevention programmes. Recommendations for future research into the social networks of IDUs are proposed.

  19. Methods for medical device and equipment procurement and prioritization within low- and middle-income countries: findings of a systematic literature review.

    Science.gov (United States)

    Diaconu, Karin; Chen, Yen-Fu; Cummins, Carole; Jimenez Moyao, Gabriela; Manaseki-Holland, Semira; Lilford, Richard

    2017-08-18

    Forty to 70 % of medical devices and equipment in low- and middle-income countries are broken, unused or unfit for purpose; this impairs service delivery to patients and results in lost resources. Undiscerning procurement processes are at the heart of this issue. We conducted a systematic review of the literature to August 2013 with no time or language restrictions to identify what product selection or prioritization methods are recommended or used for medical device and equipment procurement planning within low- and middle-income countries. We explore the factors/evidence-base proposed for consideration within such methods and identify prioritization criteria. We included 217 documents (corresponding to 250 texts) in the narrative synthesis. Of these 111 featured in the meta-summary. We identify experience and needs-based methods used to reach procurement decisions. Equipment costs (including maintenance) and health needs are the dominant issues considered. Extracted data suggest that procurement officials should prioritize devices with low- and middle-income country appropriate technical specifications - i.e. devices and equipment that can be used given available human resources, infrastructure and maintenance capacity. Suboptimal device use is directly linked to incomplete costing and inadequate consideration of maintenance services and user training during procurement planning. Accurate estimation of life-cycle costing and careful consideration of device servicing are of crucial importance.

  20. Mechanics of aerosols in nuclear reactor safety: a review

    International Nuclear Information System (INIS)

    Loyalka, S.K.

    1983-01-01

    Although the estimated public risks from nuclear reactors are not high, a significant fraction of these arises from the accident sequences that lead to severe core damage. Calculation of release fractions of the core radioactive inventories for such accidents requires an understanding of the evolution of aerosols in primary coolant systems and reactor containment. The state-of-the-art in the mechanics of a single aerosol particle is reviewed and available work on coagulation of two aerosol particles is discussed. Progress in kinetic theory descriptions and experimental works is described and directions of future work are noted. The General Dynamic Equation for the aerosol distribution is considered, and several forms of this for conditions of interest are noted. Methods of solution that are discussed include analytical techniques, similarity transforms, moments methods and numerical techniques. Computer programs that have been developed in the past few years are also discussed, and their capabilities and limitations are noted. Finally, the comparison of computed results with the available experimental data is discussed, and needs for future research are emphasized. (author)

  1. Innovation and problem solving: a review of common mechanisms.

    Science.gov (United States)

    Griffin, Andrea S; Guez, David

    2014-11-01

    Behavioural innovations have become central to our thinking about how animals adjust to changing environments. It is now well established that animals vary in their ability to innovate, but understanding why remains a challenge. This is because innovations are rare, so studying innovation requires alternative experimental assays that create opportunities for animals to express their ability to invent new behaviours, or use pre-existing ones in new contexts. Problem solving of extractive foraging tasks has been put forward as a suitable experimental assay. We review the rapidly expanding literature on problem solving of extractive foraging tasks in order to better understand to what extent the processes underpinning problem solving, and the factors influencing problem solving, are in line with those predicted, and found, to underpin and influence innovation in the wild. Our aim is to determine whether problem solving can be used as an experimental proxy of innovation. We find that in most respects, problem solving is determined by the same underpinning mechanisms, and is influenced by the same factors, as those predicted to underpin, and to influence, innovation. We conclude that problem solving is a valid experimental assay for studying innovation, propose a conceptual model of problem solving in which motor diversity plays a more central role than has been considered to date, and provide recommendations for future research using problem solving to investigate innovation. This article is part of a Special Issue entitled: Cognition in the wild. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. An Updated Review of the Molecular Mechanisms in Drug Hypersensitivity

    Directory of Open Access Journals (Sweden)

    Chun-Bing Chen

    2018-01-01

    Full Text Available Drug hypersensitivity may manifest ranging from milder skin reactions (e.g., maculopapular exanthema and urticaria to severe systemic reactions, such as anaphylaxis, drug reactions with eosinophilia and systemic symptoms (DRESS/drug-induced hypersensitivity syndrome (DIHS, or Stevens–Johnson syndrome (SJS/toxic epidermal necrolysis (TEN. Current pharmacogenomic studies have made important strides in the prevention of some drug hypersensitivity through the identification of relevant genetic variants, particularly for genes encoding drug-metabolizing enzymes and human leukocyte antigens (HLAs. The associations identified by these studies are usually drug, phenotype, and ethnic specific. The drug presentation models that explain how small drug antigens might interact with HLA and T cell receptor (TCR molecules in drug hypersensitivity include the hapten theory, the p-i concept, the altered peptide repertoire model, and the altered TCR repertoire model. The broad spectrum of clinical manifestations of drug hypersensitivity involving different drugs, as well as the various pathomechanisms involved, makes the diagnosis and management of it more challenging. This review highlights recent advances in our understanding of the predisposing factors, immune mechanisms, pathogenesis, diagnostic tools, and therapeutic approaches for drug hypersensitivity.

  3. Anthocyanin Biosynthesis and Degradation Mechanisms in Solanaceous Vegetables: A Review

    Directory of Open Access Journals (Sweden)

    Ying Liu

    2018-03-01

    Full Text Available Anthocyanins are a group of polyphenolic pigments that are ubiquitously found in the plant kingdom. In plants, anthocyanins play a role not only in reproduction, by attracting pollinators and seed dispersers, but also in protection against various abiotic and biotic stresses. There is accumulating evidence that anthocyanins have health-promoting properties, which makes anthocyanin metabolism an interesting target for breeders and researchers. In this review, the state of the art knowledge concerning anthocyanins in the Solanaceous vegetables, i.e., pepper, tomato, eggplant, and potato, is discussed, including biochemistry and biological function of anthocyanins, as well as their genetic and environmental regulation. Anthocyanin accumulation is determined by the balance between biosynthesis and degradation. Although the anthocyanin biosynthetic pathway has been well-studied in Solanaceous vegetables, more research is needed on the inhibition of biosynthesis and, in particular, the anthocyanin degradation mechanisms if we want to control anthocyanin content of Solanaceous vegetables. In addition, anthocyanin metabolism is distinctly affected by environmental conditions, but the molecular regulation of these effects is poorly understood. Existing knowledge is summarized and current gaps in our understanding are highlighted and discussed, to create opportunities for the development of anthocyanin-rich crops through breeding and environmental management.

  4. Nonextensive statistical mechanics: a brief review of its present status

    Directory of Open Access Journals (Sweden)

    CONSTANTINO TSALLIS

    2002-09-01

    Full Text Available We briefly review the present status of nonextensive statistical mechanics. We focus on (i the central equations of the formalism, (ii the most recent applications in physics and other sciences, (iii the a priori determination (from microscopic dynamics of the entropic index q for two important classes of physical systems, namely low-dimensional maps (both dissipative and conservative and long-range interacting many-body hamiltonian classical systems.Revisamos sumariamente o estado presente da mecânica estatística não-extensiva. Focalizamos em (i as equacões centrais do formalismo; (ii as aplicações mais recentes na física e em outras ciências, (iii a determinação a priori (da dinâmica microscópica do índice entrópico q para duas classes importantes de sistemas físicos, a saber, mapas de baixa dimensão (tanto dissipativos quanto conservativos e sistemas clássicos hamiltonianos de muitos corpos com interações de longo alcance.

  5. An Updated Review of the Molecular Mechanisms in Drug Hypersensitivity

    Science.gov (United States)

    Abe, Riichiro; Pan, Ren-You; Wang, Chuang-Wei

    2018-01-01

    Drug hypersensitivity may manifest ranging from milder skin reactions (e.g., maculopapular exanthema and urticaria) to severe systemic reactions, such as anaphylaxis, drug reactions with eosinophilia and systemic symptoms (DRESS)/drug-induced hypersensitivity syndrome (DIHS), or Stevens–Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN). Current pharmacogenomic studies have made important strides in the prevention of some drug hypersensitivity through the identification of relevant genetic variants, particularly for genes encoding drug-metabolizing enzymes and human leukocyte antigens (HLAs). The associations identified by these studies are usually drug, phenotype, and ethnic specific. The drug presentation models that explain how small drug antigens might interact with HLA and T cell receptor (TCR) molecules in drug hypersensitivity include the hapten theory, the p-i concept, the altered peptide repertoire model, and the altered TCR repertoire model. The broad spectrum of clinical manifestations of drug hypersensitivity involving different drugs, as well as the various pathomechanisms involved, makes the diagnosis and management of it more challenging. This review highlights recent advances in our understanding of the predisposing factors, immune mechanisms, pathogenesis, diagnostic tools, and therapeutic approaches for drug hypersensitivity. PMID:29651444

  6. Anthocyanin biosynthesis and degradation mechanisms in Solanaceous vegetables: a review

    Science.gov (United States)

    Liu, Ying; Tikunov, Yury; Schouten, Rob E.; Marcelis, Leo F. M.; Visser, Richard G. F.; Bovy, Arnaud

    2018-03-01

    Anthocyanins are a group of polyphenolic pigments that are ubiquitously found in the plant kingdom. In plants, anthocyanins play a role not only in reproduction, by attracting pollinators and seed dispersers, but also in protection against various abiotic and biotic stresses. There is accumulating evidence that anthocyanins have health-promoting properties, which makes anthocyanin metabolism an interesting target for breeders and researchers. In this review, the state of the art knowledge concerning anthocyanins in the Solanaceous vegetables, i.e. pepper, tomato, eggplant and potato, is discussed, including biochemistry and biological function of anthocyanins, as well as their genetic and environmental regulation. Anthocyanin accumulation is determined by the balance between biosynthesis and degradation. Although the anthocyanin biosynthetic pathway has been well studied in Solanaceous vegetables, more research is needed on the inhibition of biosynthesis and, in particular, the anthocyanin degradation mechanisms if we want to control anthocyanin content of Solanaceous vegetables. In addition, anthocyanin metabolism is distinctly affected by environmental conditions, but the molecular regulation of these effects is poorly understood. Existing knowledge is summarized and current gaps in our understanding are highlighted and discussed, to create opportunities for the development of anthocyanin-rich crops through breeding and environmental management.

  7. Rearrangement of the layout of the welding equipment of a company in the metal mechanical sector using the Systematic Layout Planning method (SLP

    Directory of Open Access Journals (Sweden)

    Silvio Alexsandro Turati

    2016-06-01

    Full Text Available The correct physical layout is relevant to the operational efficiency of the company. This study proposes rearranging the layout of the welding equipment of a company in the metal mechanical sector, which is located in Araras/SP, aiming to improve the production workflow. The Systematic Layout Planning method (SLP was used, with the field research divided into steps: obtaining detailed information about the process and the product; meetings with stakeholders; determining inter-related activities; analyzing space requirements; developing a new layout. The new layout has space allocated for the purchasing of new machinery, the existing machinery has been redistributed by specialty, and the unloading of raw materials has been transferred to the shed, maximizing the use of overhead cranes and keeping the stock close to the warehouse. In addition, forklift traffic flow has decreased; new movement corridors were demarcated; and painting areas were isolated. In conclusion, the SLP method proved efficient in creating a layout.

  8. The structure and physical-mechanical properties of the heat-resistant Ni-Co-Cr-Al-Y intermetallic coating obtained using rebuilt plasma equipment

    Science.gov (United States)

    Tarasenko, Yu. P.; Tsareva, I. N.; Berdnik, O. B.; Fel, Ya. A.; Kuzmin, V. I.; Mikhalchenko, A. A.; Kartaev, E. V.

    2014-12-01

    Results of a study of the structure, physico-mechanical properties, and the resistance to heat of Ni-Co-Cr-Al-Y intermetallic coatings obtained by powder spraying on the standard UPU-3D plasma spray facility (plasmatron with self-establishing arc length) and on the rebuilt facility equipped with the enhanced-power PNK-50 plasmatron with sectionalized inter-electrode insert, are reported. Coatings of higher density ( ρ = 7.9 g/cm3) and higher microhardness (H μ = 770 kg-force/mm2) with lower porosity values ( P = 5.7 %, P c = 5.1 %, and P 0 = 0.6 %) and high resistance to heat ((M - M0)/M0 = 1.2) were obtained. The developed coating is intended for protection of the working surfaces of turbine engine blades in gas-turbine power plants.

  9. A review on mechanical properties of magnesium based nano composites

    Science.gov (United States)

    Tarafder, Nilanjan; Prasad, M. Lakshmi Vara

    2018-04-01

    A review was done on Magnesium (Mg) based composite materials reinforced with different nano particles such as TiO2, Cu, Y2O3, SiC, ZrO2 and Al2O3. TiO2 and Al2O3 nanoparticles were synthesised by melt deposition process. Cu, Y2O3, SiC and ZrO2 nanoparticles were synthesised by powder metallurgy process. Composite microstructural characteristics shows that the nano-size reinforcements are uniformly distributed in the composite matrix and also minimum porosity with solid interfacial integrity. The mechanical properties showed yield strength improvement by 0.2 percentage and Ultimate tensile strength (UTS) was also improved for all the nano-particles. But UTS was adversely affected with TiO2 reinforcement while ductility was increased. With Cu reinforcement elastic modulus, hardness and fracture resistance increased and improved the co-efficient of thermal expansion (CTE) of Mg based matrix. By Y2O3 reinforcement hardness, fracture resistance was improved and ductility reached maximum by 0.22 volume percentage of Y2O3 and decreased with succeeding increase in Y2O3 reinforcement. The readings exposed that mechanical properties were gathered from the composite comprising 2.0 weight percentage of Y2O3. Ductility and fracture resistance increased with ZrO2 reinforcement in Mg matrix. Using Al2O3 as reinforcement in Mg composite matrix hardness, elastic modulus and ductility was increased but porosity reduced with well interfacial integrity. Dissipation of energy in the form of damping capacity was resolved by classical vibration theory. The result showed that an increasing up to 0.4 volume percentage alumina content increases the damping capacity up to 34 percent. In another sample, addition of 2 weight percentage nano-Al2O3 particles showed big possibility in reducing CTE from 27.9-25.9×10-6 K-1 in Magnesium, tensile and yield strength amplified by 40MPa. In another test, Mg/1.1Al2O3 nanocomposite was manufactured by solidification process followed by hot extrusion

  10. Plastic deformation mechanisms of the uranium-alpha. Review

    International Nuclear Information System (INIS)

    Loureiro, A.P.

    1975-01-01

    A survey of the bibliography on the behaviour of the alpha-Uranium during its plastic deformation is made, with the aim of knowing the mechanisms which control that deformation. An analysis is made of some of the mechanisms suggested in the literature as controlling, with particular emphasis on the Peierls-Nabarro mechanism

  11. Obesity and Pulmonary Hypertension: A Review of Pathophysiologic Mechanisms

    Directory of Open Access Journals (Sweden)

    Scott E. Friedman

    2012-01-01

    Full Text Available Pulmonary hypertension (PH is a potentially life-threatening condition arising from a wide variety of pathophysiologic mechanisms. Effective treatment requires a systematic diagnostic approach to identify all reversible mechanisms. Many of these mechanisms are relevant to those afflicted with obesity. The unique mechanisms of PH in the obese include obstructive sleep apnea, obesity hypoventilation syndrome, anorexigen use, cardiomyopathy of obesity, and pulmonary thromboembolic disease. Novel mechanisms of PH in the obese include endothelial dysfunction and hyperuricemia. A wide range of effective therapies exist to mitigate the disability of PH in the obese.

  12. Seismic verification of nuclear plant equipment anchorage

    International Nuclear Information System (INIS)

    Lepiece, M.; Van Vyve, J.

    1991-01-01

    More than 60% of the electrical power of Belgium is generated by seven PWR nuclear power plants. For three of them, the electro-mechanical equipment had to be reassessed after ten years of operation, because the seismic requirements were upgraded from 0.1 g to 0.17 g free field ground acceleration. The seismic requalification of the active equipment was a critical problem as the classical methods were too conservative. The approach based on the use of the past experience on the seismic behavior of nonnuclear equipment, chosen and developed by the SQUG, had to be transposed to the Belgian N.P.P. The decision of the accept-ability of equipment relies heavily on the aseismatic capacity of anchorage. The Electrical Power Research Institute (EPRI) developed the procedure and guideline for the demonstration of the aseismatic adequacy of equipment anchorage in a cost-effective and consistent manner, to support the decision by Seismic Review Team. The field inspection procedure to identify the type of fasteners and detect their possible defects and the verification procedure developed to calculate the aseismatic capacity of equipment anchorage on the strength of fasteners, the aseismatic capacity of anchorage and the comparison of the capacity with the demand are reported. (K.I.)

  13. Genetic and epigenetic mechanisms of epilepsy: a review

    Directory of Open Access Journals (Sweden)

    Chen T

    2017-07-01

    Full Text Available Tian Chen,1,* Mohan Giri,2,* Zhenyi Xia,3 Yadu Nanda Subedi,2 Yan Li1 1Department of Health Management Center, Chongqing Three Gorges Central Hospital, Chongqing, People’s Republic of China; 2National Center for Rheumatic Diseases, Ratopul, Gaushala, Kathmandu, Nepal; 3Department of Thoracic Surgery, Chongqing Three Gorges Central Hospital, Chongqing, People’s Republic of China *These authors contributed equally to this work Abstract: Epilepsy is a common episodic neurological disorder or condition characterized by recurrent epileptic seizures, and genetics seems to play a key role in its etiology. Early linkage studies have localized multiple loci that may harbor susceptibility genes to epilepsy, and mutational analyses have detected a number of mutations involved in both ion channel and nonion channel genes in patients with idiopathic epilepsy. Genome-wide studies of epilepsy have found copy number variants at 2q24.2-q24.3, 7q11.22, 15q11.2-q13.3, and 16p13.11-p13.2, some of which disrupt multiple genes, such as NRXN1, AUTS2, NLGN1, CNTNAP2, GRIN2A, PRRT2, NIPA2, and BMP5, implicated for neurodevelopmental disorders, including intellectual disability and autism. Unfortunately, only a few common genetic variants have been associated with epilepsy. Recent exome-sequencing studies have found some genetic mutations, most of which are located in nonion channel genes such as the LGI1, PRRT2, EFHC1, PRICKLE, RBFOX1, and DEPDC5 and in probands with rare forms of familial epilepsy, and some of these genes are involved with the neurodevelopment. Since epigenetics plays a role in neuronal function from embryogenesis and early brain development to tissue-specific gene expression, epigenetic regulation may contribute to the genetic mechanism of neurodevelopment through which a gene and the environment interacting with each other affect the development of epilepsy. This review focused on the analytic tools used to identify epilepsy and then provided a

  14. Nacre biomineralisation: A review on the mechanisms of crystal nucleation.

    Science.gov (United States)

    Nudelman, Fabio

    2015-10-01

    The wide diversity of biogenic minerals that is found in nature, each with its own morphology, mechanical properties and composition, is remarkable. In order to produce minerals that are optimally adapted for their function, biomineralisation usually occurs under strict cellular control. This control is exerted by specialised proteins and polysaccharides that assemble into a 3-dimensional organic matrix framework, forming a microenvironment where mineral deposition takes place. Molluscs are unique in that they use a striking variety of structural motifs to build their shells, each made of crystals with different morphologies and different calcium carbonate polymorphs. Much of want is known about mollusc shell formation comes from studies on the nacreous layer, or mother-of-pearl. In this review, we discuss two existing models on the nucleation of aragonite crystals during nacre formation: heteroepitaxial nucleation and mineral bridges. The heteroepitaxial nucleation model is based on the identification of chemical functional groups and aragonite-nucleating proteins at the centre of crystal imprints. It proposes that during nacre formation, each aragonite tablet nucleates independently on a nucleation site that is formed by acidic proteins and/or glycoproteins adsorbed on the chitin scaffold. The mineral bridges model is based on the identification of physical connections between the crystals in a stack, which results in a large number of crystals across several layers sharing the same crystallographic orientation. These observations suggest that there is one nucleation event per stack of tablets. Once the first crystal nucleates and reaches the top interlamellar matrix, it continues growing through pores, giving rise to the next layer of nacre, subsequently propagating into a stack. We compare both models and propose that they work in concert to control crystal nucleation in nacre. De novo crystal nucleation has to occur at least once per stack of aligned crystals

  15. Analysis of Technical State of Thermal and Mechanical Equipment of Thermal Power Stations in the Republic of Belarus under Conditions of Investment Deficit

    Directory of Open Access Journals (Sweden)

    S. N. Shichko

    2004-01-01

    Full Text Available The paper contains an analysis of the equipment state at a number of thermal power stations. This analysis is made on the basis of indifferent curves. Relationship of two factors is taken as a criterion for estimation of the equipment state. These factors are faultiness (parameter of failure fi"equency and operating time from the moment when the equipment was put into operation. It is noted that operation of the equipment in excess of specified life without replacement of so-called «weab> elements and estimation of metal state will lead to conditions of high risk in opieration of such equipment.

  16. Experimental equipment, ch. 6

    International Nuclear Information System (INIS)

    Boomstra, F.; Hoogenboom, A.M.; Prins, C.M.; Strasters, B.A.; Vermeer, A.; Wit, P. de; Zwol, N.A. van.

    1977-01-01

    The experimental equipment in use at Utrecht university is discussed. Attention is paid to the tandem Van de Graaff accelerator and the 4MV and 1MV accelerators. The detection systems for gamma-ray spectroscopy are reviewed with emphasis on the compton-suppression spectrometer. The data-handling system used for experiments with the tandem is also briefly discussed

  17. Safeguards techniques and equipment

    International Nuclear Information System (INIS)

    1997-01-01

    The current booklet is intended to give a full and balanced description of the techniques and equipment used for both nuclear material accountancy and containment and surveillance measures, and for the new safeguards measure of environmental sampling. As new verification measures continue to be developed, the material in the booklet will be periodically reviewed and updated versions issued. (author)

  18. A Review of Sex Determining Mechanisms in Geckos (Gekkota: Squamata)

    OpenAIRE

    Gamble, T.

    2010-01-01

    Geckos are a species-rich clade of reptiles possessing diverse sex determining mechanisms. Some species possess genetic sex determination, with both male and female heterogamety, while other species have temperature-dependent sex determination. I compiled information from the literature on the taxonomic distribution of these sex determining mechanisms in geckos. Using phylogenetic data from the literature, I reconstructed the minimum number of transitions among these sex determining mechanism...

  19. 78 FR 36190 - Agency Information Collection Activities; Submission for OMB Review; IT Dashboard Feedback Mechanism

    Science.gov (United States)

    2013-06-17

    ... Information Collection Activities; Submission for OMB Review; IT Dashboard Feedback Mechanism AGENCY: Office... to review and approve a previously approved information collection requirement regarding IT Dashboard... identified by Information Collection 3090- 0285, IT Dashboard Feedback Mechanism, by any of the following...

  20. Sufficient Flexibility and Capacity in Electricity Markets with Renewables: A Review of Innovative Market Mechanisms

    DEFF Research Database (Denmark)

    Sekamane, Jonas Khubute; Katz, Jonas; Skytte, Klaus

    2017-01-01

    This review of the literature collects innovative market mechanisms that tend to get overlooked in the discussion of whether unassisted energy-only markets can ensure sufficient capacity or if capacity remuneration mechanisms are required. The paper complements existing literature reviews...... and pinpoints advantageous research areas relating to the market design of electricity systems with high shares of variable renewable energy...

  1. Proceedings of the Annual Mechanics of Composites Review (6th),

    Science.gov (United States)

    1981-02-01

    LONG RANGE ARTILLERY PROJECTILES: E. Lenoe, D. Oplinger, K. Ghandi , Army Materials & Mechanics Research Center 129 PRELIMINARY DESIGN ASSESSMENT OF...RANGE ARTILLERY PROJECTILES E. Lenoe, D. Oplinger, K. Ghandi Army Materials & Mechanics Research Center/DRXMR-TM Watertown, MA 02172 Material not

  2. Mini-review: Molecular mechanisms of antifouling compounds

    KAUST Repository

    Qian, Pei-Yuan; Chen, Lianguo; Xu, Ying

    2013-01-01

    Various antifouling (AF) coatings have been developed to protect submerged surfaces by deterring the settlement of the colonizing stages of fouling organisms. A review of the literature shows that effective AF compounds with specific targets

  3. Policy-Relevant Systematic Reviews to Strengthen Health Systems: Models and Mechanisms to Support Their Production

    Science.gov (United States)

    Oliver, Sandra; Dickson, Kelly

    2016-01-01

    Support for producing systematic reviews about health systems is less well developed than for those about clinical practice. From interviewing policy makers and systematic reviewers we identified institutional mechanisms which bring systematic reviews and policy priorities closer by harnessing organisational and individual motivations, emphasising…

  4. Potential mechanisms linking probiotics to diabetes: a narrative review of the literature

    OpenAIRE

    Miraghajani, Maryam; Dehsoukhteh, Somayeh Shahraki; Rafie, Nahid; Hamedani, Sahar Golpour; Sabihi, Sima; Ghiasvand, Reza

    2017-01-01

    ABSTRACT CONTEXT AND OBJECTIVE: Some studies have suggested a wide range of possible mechanisms through which probiotics may play a role in diabetes prevention and treatment. However, the underlying mechanisms are not fully understood. We conducted this study to review the potential mechanisms suggested for the effect of probiotics in diabetes. DESIGN AND SETTING: Narrative review conducted at the Food Security Research Center of Isfahan. METHODS: A search in the electronic databases ME...

  5. Development of Universal Methodology of Specimen Free Nondestructive Inspection (Control) of Mechanical Properties of NPP Equipment Metal in all Stages of Lifetime

    International Nuclear Information System (INIS)

    Bakirov, M.; Chubarov, S.; Frolov, I.; Kiselev, I.; Gastrock, J.; Dripke, M.

    2011-01-01

    indications on tensile yield stress elevation due to hardening and also loss in ductility. The work-hardening index may be easily obtained, giving information on the ability of the material (e.g. pressure vessel steel and weld) to deform plastically without brittle fracture. Taking into account the experience of the Center of Material Science and Lifetime Management Ltd. (CMSLM Ltd.) in the use of methods of hardness testing for the inspection of the equipment of NPP of Russian manufacture in Russia, Germany, Czech, Slovakia, Bulgaria, and also similar successful works in this direction in USA (Oakridge), to Czech (NRI Rez) and other countries, it can be seen that the most promising direction in the field of specimen-free inspection of mechanical properties by use of hardness and hardness-related characteristics is use of the kinetic indentation method (KIM, ABIT). This method is based on recording the process of elastoplastic deformation caused by the indentation of a ball indenter. This method allows one to obtain, besides hardness values, tensile properties, elongation, work hardening coefficient, true-stress/true strain diagrammes which normally required the destructive testing of small specimens. However, till now there is no universal method of interpreting the information obtained, although it is generally known that irradiation causes a loss in ductility and increase in hardness and lowering of the work-hardening coefficient. Thus, it is necessary to develop a uniform methodology of using KIM, ABIT with reference to the inspection of materials which will allow unifying the inspection of materials of various classes of the equipment of NPP over all stages of life cycle. With the purpose of introduction of such a methodology it is necessary to develop and realize the program in the frames of IAEA with the above name. (author)

  6. Conservative management of mechanical neck disorders: a systematic review

    NARCIS (Netherlands)

    Gross, Anita R.; Goldsmith, Charlie; Hoving, Jan L.; Haines, Ted; Peloso, Paul; Aker, Peter; Santaguida, Pasqualina; Myers, Cynthia

    2007-01-01

    OBJECTIVE: To determine if conservative treatments (manual therapies, physical medicine methods, medication, and patient education) relieved pain or improved function/disability, patient satisfaction, and global perceived effect in adults with acute, subacute, and chronic mechanical neck disorders

  7. A Review of Sex Determining Mechanisms in Geckos (Gekkota: Squamata)

    Science.gov (United States)

    Gamble, T.

    2010-01-01

    Geckos are a species-rich clade of reptiles possessing diverse sex determining mechanisms. Some species possess genetic sex determination, with both male and female heterogamety, while other species have temperature-dependent sex determination. I compiled information from the literature on the taxonomic distribution of these sex determining mechanisms in geckos. Using phylogenetic data from the literature, I reconstructed the minimum number of transitions among these sex determining mechanisms with parsimony-based ancestral state reconstruction. While only a small number of gecko species have been characterized, numerous changes among sex determining mechanisms were inferred. This diversity, coupled with the high frequency of transitions, makes geckos excellent candidates as a model clade for the study of vertebrate sex determination and evolution. PMID:20234154

  8. Chair in mechanical equipment in the mining industry and geotechnics at Clausthal Technological University; Professur fuer maschinelle Betriebsmittel in Bergbau und Geotechnik an der TU Clausthal

    Energy Technology Data Exchange (ETDEWEB)

    Langefeld, O.; Bergmann, O. [Technische Univ. Clausthal, Clausthal-Zellerfeld (Germany). Inst. fuer Bergbau

    2002-10-10

    The aim of this chair at the Institute for Mining at Clausthal Technological University is to familiarise the future engineer with the state of the art in the field of mechanical equipment. The main emphasis of the teaching is in particular the description of coal-mining and roadheading machines as well as conveying and storage technology. In the field of research basic investigations are currently being conducted on flexible bulk material containers, on determination of heat characteristics of insulating and construction materials as well as development of direct methanol fuel cells. (orig.) [German] Den zukuenftigen Ingenieur mit dem Stand der Technik im Bereich der maschinellen Betriebsmittel vertraut zu machen, ist das Ziel dieser Professur des Instituts fuer Bergbau an der TU Clausthal. Schwerpunkte der Lehre sind insbesondere die Darstellung von Gewinnungs- und Vortriebsmaschinen sowie die Foerder- und Lagertechnik. Auf dem Gebiet der Forschung werden zur Zeit Grundlagenuntersuchungen an flexiblem Schuettgutbehaeltern, an der Ermittlung waermetechnischer Kennwerte von Isolier- und Baustoffen sowie die Entwicklung von Direkten Methanolbrennstoffzellen betrieben. (orig.)

  9. [Hydrotherapy equipment].

    Science.gov (United States)

    Tsibikov, V B; Ragozin, S I; Mikheeva, L V

    1985-01-01

    A flow-chart is developed demonstrating the relation between medical and prophylactic institutions within the organizational structure of the rehabilitation system and main types of rehabilitation procedures. In order to ascertain the priority in equipping rehabilitation services with adequate hardware the special priority criterion is introduced. The highest priority is assigned to balneotherapeutic and fangotherapeutic services. Based on the operation-by-operation analysis of clinical processes related to service and performance of balneologic procedures the preliminary set of clinical devices designed for baths, basins and showers in hospitals and rehabilitation departments is defined in a generalized form.

  10. Methods, Mechanism, and Applications of Photodeposition in Photocatalysis: A Review

    NARCIS (Netherlands)

    Wenderich, Kasper; Mul, Guido

    2016-01-01

    In this review, for a variety of metals and semiconductors, an attempt is made to generalize observations in the literature on the effect of process conditions applied during photodeposition on (i) particle size distributions, (ii) oxidation states of the metals obtained, and (iii) consequences for

  11. Pain and disability in osteoarthritis : a review of biobehavioral mechanisms

    NARCIS (Netherlands)

    Dekker, J; Boot, B; van der Woude, L H; Bijlsma, J W

    Pain and disability are cardinal symptoms in osteoarthritis. The literature is reviewed in order to identify causes of these symptoms at the articular, kinesiological, and psychological level. It is concluded that pain and disability are associated with degeneration of cartilage and bone (articular

  12. A review on the molecular mechanism of plants rooting modulated ...

    African Journals Online (AJOL)

    Phytohormones, especially auxin, played an essential role in regulating roots developments. This review focused on recent advances in the research of plants rooting genomics and proteomics, including auxin biosynthesis, metabolism, transport, and signaling pathway which are involved in modulating plants rooting and ...

  13. Book review: Partial Differential Equations and Fluid Mechanics

    NARCIS (Netherlands)

    Muntean, A.

    2011-01-01

    The baak is the result of the workshop Partial Differential Equations and Fluid Dynamics that look place at the Mathematics Institute of the University of Warwick. May 21st - 23rd, 2007. It contains ten review and research papers which provide an accessible summary of a wide range of active research

  14. A 100-Year Review: A century of dairy processing advancements-Pasteurization, cleaning and sanitation, and sanitary equipment design.

    Science.gov (United States)

    Rankin, S A; Bradley, R L; Miller, G; Mildenhall, K B

    2017-12-01

    Over the past century, advancements within the mainstream dairy foods processing industry have acted in complement with other dairy-affiliated industries to produce a human food that has few rivals with regard to safety, nutrition, and sustainability. These advancements, such as milk pasteurization, may appear commonplace in the context of a modern dairy processing plant, but some consideration of how these advancements came into being serve as a basis for considering what advancements will come to bear on the next century of processing advancements. In the year 1917, depending on where one resided, most milk was presented to the consumer through privately owned dairy animals, small local or regional dairy farms, or small urban commercial dairies with minimal, or at best nascent, processing capabilities. In 1917, much of the retail milk in the United States was packaged and sold in returnable quart-sized clear glass bottles fitted with caps of various design and composition. Some reports suggest that the cost of that quart of milk was approximately 9 cents-an estimated $2.00 in 2017 US dollars. Comparing that 1917 quart of milk to a quart of milk in 2017 suggests several differences in microbiological, compositional, and nutritional value as well as flavor characteristics. Although a more comprehensive timeline of significant processing advancements is noted in the AppendixTable A1 to this paper, we have selected 3 advancements to highlight; namely, the development of milk pasteurization, cleaning and sanitizing technologies, and sanitary specifications for processing equipment. Finally, we provide some insights into the future of milk processing and suggest areas where technological advancements may need continued or strengthened attention and development as a means of securing milk as a food of high safety and value for the next century to come. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  15. Review of Student Difficulties in Upper-Level Quantum Mechanics

    Science.gov (United States)

    Singh, Chandralekha; Marshman, Emily

    2015-01-01

    Learning advanced physics, in general, is challenging not only due to the increased mathematical sophistication but also because one must continue to build on all of the prior knowledge acquired at the introductory and intermediate levels. In addition, learning quantum mechanics can be especially challenging because the paradigms of classical…

  16. Tumor necrosis factor antagonist mechanisms of action: a comprehensive review

    NARCIS (Netherlands)

    Tracey, Daniel; Klareskog, Lars; Sasso, Eric H.; Salfeld, Jochen G.; Tak, Paul P.

    2008-01-01

    During the past 30 years, elucidation of the pathogenesis of rheumatoid arthritis, Crohn's disease, psoriasis, psoriatic arthritis and ankylosing spondylitis at the cellular and molecular levels has revealed that these diseases share common mechanisms and are more closely related than was previously

  17. Suicide Clusters: A Review of Risk Factors and Mechanisms

    Science.gov (United States)

    Haw, Camilla; Hawton, Keith; Niedzwiedz, Claire; Platt, Steve

    2013-01-01

    Suicide clusters, although uncommon, cause great concern in the communities in which they occur. We searched the world literature on suicide clusters and describe the risk factors and proposed psychological mechanisms underlying the spatio-temporal clustering of suicides (point clusters). Potential risk factors include male gender, being an…

  18. Current Status of Mechanical Circulatory Support: A Systematic Review

    Directory of Open Access Journals (Sweden)

    Kyriakos Spiliopoulos

    2012-01-01

    Full Text Available Heart failure is a major public health problem and its management requires a significant amount of health care resources. Even with administration of the best available medical treatment, the mortality associated with the disease remains high. As therapeutical strategies for heart failure have been refined, the number of patients suffering from the disease has expanded dramatically. Although heart transplantation still represents the gold standard therapeutical approach, the implantation of mechanical circulatory support devices (MCSDs evolved to a well-established management for this disease. The limited applicability of heart transplantation caused by a shortage of donor organs and the concurrent expand of the patient population with end-stage heart failure led to a considerable utilization of MCSDs. This paper outlines the current status of mechanical circulatory support.

  19. A Review of the Mechanical Properties of Concrete Containing Biofillers

    Science.gov (United States)

    Ezdiani Mohamad, Mazizah; Mahmood, Ali A.; Min, Alicia Yik Yee; Khalid, Nur Hafizah A.

    2016-11-01

    Sustainable construction is a rapidly increasing research area. Investigators of all backgrounds are using industrial and agro wastes to replace Portland cement in concrete to reduce greenhouse emissions and the corresponding decline in general health. Many types of wastes have been used as cement replacements in concrete including: fly ash, slag and rice husk ash in addition to others. This study investigates the possibility of producing a sustainable approach to construction through the partial replacement of concrete using biofillers. This will be achieved by studying the physical and mechanical properties of two widely available biological wastes in Malaysia; eggshell and palm oil fuel ash (POFA). The mechanical properties tests that were studied and compared are the compression, tensile and flexural tests.

  20. Review of research on the mechanical properties of the human tooth

    Science.gov (United States)

    Zhang, Ya-Rong; Du, Wen; Zhou, Xue-Dong; Yu, Hai-Yang

    2014-01-01

    ‘Bronze teeth' reflect the mechanical properties of natural teeth to a certain extent. Their mechanical properties resemble those of a tough metal, and the gradient of these properties lies in the direction from outside to inside. These attributes confer human teeth with effective mastication ability. Understanding the various mechanical properties of human teeth and dental materials is the basis for the development of restorative materials. In this study, the elastic properties, dynamic mechanical properties (visco-elasticity) and fracture mechanical properties of enamel and dentin were reviewed to provide a more thorough understanding of the mechanical properties of human teeth. PMID:24743065

  1. A Review of Neuropathic Pain: From Diagnostic Tests to Mechanisms

    OpenAIRE

    Truini, Andrea

    2017-01-01

    Neuropathic pain develops when the somatosensory nervous system is affected by a lesion or disease. Diagnostic tests aimed at assessing somatosensory afferent pathway damage are therefore useful for diagnosing neuropathic pain. Neuropathic pain manifests with a range of different symptoms such as ongoing burning pain, squeezing or pressure pain, paroxysmal electric shock-like sensations, stabbing pain, or mechanical dynamic allodynia. The various types of neuropathic pain are associated with ...

  2. Chest physiotherapy in mechanically ventilated children: a review.

    Science.gov (United States)

    Krause, M F; Hoehn, T

    2000-05-01

    Many physicians, nurses, and respiratory care practitioners consider chest physiotherapy (CP) a standard therapy in mechanically ventilated children beyond the newborn period. CP includes percussion, vibration, postural drainage, assisted coughing, and suctioning via the endotracheal tube. We searched the medical literature by using the key words "chest physiotherapy" and "chest physical therapy" (among others) by means of the MEDLINE and Current Contents databases. Because of the paucity of objective data, we examined all reports dealing with this topic, including studies on adult patients. For data extraction, not enough material existed to perform a meta-analysis. Despite its widespread use, almost no literature dealing with this treatment modality in pediatric patients exists. Studies with mechanically ventilated pediatric and adult patients have shown that CP is the most irritating routine intensive care procedure to patients. An increase in oxygen consumption often occurs when a patient receives CP accompanied by an elevation in heart rate, blood pressure, and intracranial pressure. CP leads to short-term decreases in oxygen, partial pressure in the blood, and major fluctuations in cardiac output. Changes in these vital signs and other variables may be even more pronounced in pediatric patients because the lung of a child is characterized by a higher closing capacity and the chest walls are characterized by a much higher compliance, thus predisposing the child to the development of atelectasis secondary to percussion and vibration. CP in mechanically ventilated children may not be considered a standard therapy. Controlled studies examining the impact of CP on the duration of mechanical ventilatory support, critical illness, and hospital stay are needed.

  3. Mechanisms of the anorexia of aging-a review.

    Science.gov (United States)

    Wysokiński, Adam; Sobów, Tomasz; Kłoszewska, Iwona; Kostka, Tomasz

    2015-08-01

    Many, even healthy, older people fail to adequately regulate food intake and experience loss of weight. Aging-associated changes in the regulation of appetite and the lack of hunger have been termed as the anorexia of aging. The etiology of the anorexia of aging is multi-factorial and includes a combination of physiological changes associated with aging (decline in smell and taste, reduced central and peripheral drive to eat, delayed gastric emptying), pathological conditions (depression, dementia, somatic diseases, medications and iatrogenic interventions, oral-health status), and social factors (poverty, loneliness). However, exact mechanisms of the anorexia of aging remain to be elucidated. Many neurobiological mechanisms may be secondary to age-related changes in body composition and not associated with anorexia per se. Therefore, further studies on pathophysiological mechanisms of the anorexia of aging should employ accurate measurement of body fat and lean mass. The anorexia of aging is associated with protein-energy malnutrition, sarcopenia, frailty, functional deterioration, morbidity, and mortality. Since this symptom can lead to dramatic consequences, early identification and effective interventions are needed. One of the most important goals in the geriatric care is to optimize nutritional status of the elderly.

  4. Multi-axial mechanical stimulation of tissue engineered cartilage: Review

    Directory of Open Access Journals (Sweden)

    S D Waldman

    2007-04-01

    Full Text Available The development of tissue engineered cartilage is a promising new approach for the repair of damaged or diseased tissue. Since it has proven difficult to generate cartilaginous tissue with properties similar to that of native articular cartilage, several studies have used mechanical stimuli as a means to improve the quantity and quality of the developed tissue. In this study, we have investigated the effect of multi-axial loading applied during in vitro tissue formation to better reflect the physiological forces that chondrocytes are subjected to in vivo. Dynamic combined compression-shear stimulation (5% compression and 5% shear strain amplitudes increased both collagen and proteoglycan synthesis (76 ± 8% and 73 ± 5%, respectively over the static (unstimulated controls. When this multi-axial loading condition was applied to the chondrocyte cultures over a four week period, there were significant improvements in both extracellular matrix (ECM accumulation and the mechanical properties of the in vitro-formed tissue (3-fold increase in compressive modulus and 1.75-fold increase in shear modulus. Stimulated tissues were also significantly thinner than the static controls (19% reduction suggesting that there was a degree of ECM consolidation as a result of long-term multi-axial loading. This study demonstrated that stimulation by multi-axial forces can improve the quality of the in vitro-formed tissue, but additional studies are required to further optimize the conditions to favour improved biochemical and mechanical properties of the developed tissue.

  5. Cryogenic equipment

    International Nuclear Information System (INIS)

    Leger, L.; Javellaud, J.; Caro, C.; Gilguy, R.; Testard, O.

    1966-06-01

    The cryostats presented here were built from standard parts; this makes it possible to construct a great variety of apparatus at minimum cost. The liquid nitrogen and helium reservoirs were designed so as to reduce losses to a minimum, and so as to make the cryostats as autonomous as possible. The experimental enclosure which is generally placed in the lower part of the apparatus requires a separate study in every case. Furthermore, complete assemblies such as transfer rods, isolated traps and high vacuum valves, were designed with a similar regard for the economic aspects and for the need for standardization. This equipment thus satisfies a great variety of experimental needs; it is readily adaptable and the consumptions of helium and liquid nitrogen are very low. (authors) [fr

  6. BOOK REVIEW: Mind, Matter and Quantum Mechanics (2nd edition)

    Science.gov (United States)

    Mahler, G.

    2004-07-01

    Quantum mechanics is usually defined in terms of some loosely connected axioms and rules. Such a foundation is far from the beauty of, e.g., the `principles' underlying classical mechanics. Motivated, in addition, by notorious interpretation problems, there have been numerous attempts to modify or `complete' quantum mechanics. A first attempt was based on so-called hidden variables; its proponents essentially tried to expel the non-classical nature of quantum mechanics. More recent proposals intend to complete quantum mechanics not within mechanics proper but on a `higher (synthetic) level'; by means of a combination with gravitation theory (R Penrose), with quantum information theory (C M Caves, C A Fuchs) or with psychology and brain science (H P Stapp). I think it is fair to say that in each case the combination is with a subject that, per se, suffers from a very limited understanding that is even more severe than that of quantum mechanics. This was acceptable, though, if it could convincingly be argued that scientific progress desperately needs to join forces. Quantum mechanics of a closed system was a beautiful and well understood theory with its respective state being presented as a point on a deterministic trajectory in Liouville space---not unlike the motion of a classical N-particle system in its 6N-dimensional phase-space. Unfortunately, we need an inside and an outside view, we need an external reference frame, we need an observer. This unavoidable partition is the origin of most of the troubles we have with quantum mechanics. A pragmatic solution is introduced in the form of so-called measurement postulates: one of the various incompatible properties of the system under consideration is supposed to be realized (i.e. to become a fact, to be defined without fundamental dispersion) based on `instantaneous' projections within some externally selected measurement basis. As a result, the theory becomes essentially statistical rather than deterministic

  7. Metal Additive Manufacturing: A Review of Mechanical Properties (Postprint)

    Science.gov (United States)

    2016-04-21

    treated 1,257 1,436 Laser IN718 As built NA NA 590 845 11 NA 188 Heat treated 1,133 1,240 9 EBF3 IN718 As built XY 159 580 910 22 NA 189 EBF3 IN718 As... Raman S, Christensen A. 2010. Mechanical evaluation of porous titanium (Ti6Al4V) structures with electron beam melting (EBM). J. Mech. Behav. Biomed...335 Raman Studies of Carbon Nanostructures Ado Jorio and Antonio G. Souza Filho

  8. A literature review of empirical studies of philanthropy : eight mechanisms that drive charitable giving.

    NARCIS (Netherlands)

    Bekkers, René; Wiepking, Pamala

    2010-01-01

    The authors present an overview of the academic literature on charitable giving based on a literature review of more than 500 articles. They structure their review around the central question of why people donate money to charitable organizations. We identify eight mechanisms as the most important

  9. Insights into teaching quantum mechanics in secondary and lower undergraduate education: A literature review

    NARCIS (Netherlands)

    Krijtenburg-Lewerissa, Kim; Pol, Henk; Brinkman, Alexander; van Joolingen, Wouter|info:eu-repo/dai/nl/073458872

    2017-01-01

    This study presents a review of the current state of research on teaching quantum mechanics in secondary and lower undergraduate education. A conceptual approach to quantum mechanics is being implemented in more and more introductory physics courses around the world. Because of the differences

  10. Reviews Equipment: Chameleon Nano Flakes Book: Requiem for a Species Equipment: Laser Sound System Equipment: EasySense VISION Equipment: UV Flash Kit Book: The Demon-Haunted World Book: Nonsense on Stilts Book: How to Think about Weird Things Web Watch

    Science.gov (United States)

    2011-03-01

    WE RECOMMEND Requiem for a Species This book delivers a sober message about climate change Laser Sound System Sound kit is useful for laser demonstrations EasySense VISION Data Harvest produces another easy-to-use data logger UV Flash Kit Useful equipment captures shadows on film The Demon-Haunted World World-famous astronomer attacks pseudoscience in this book Nonsense on Stilts A thought-provoking analysis of hard and soft sciences How to Think about Weird Things This book explores the credibility of astrologers and their ilk WORTH A LOOK Chameleon Nano Flakes Product lacks good instructions and guidelines WEB WATCH Amateur scientists help out researchers with a variety of online projects

  11. Reviews Equipment: Data logger Book: Imagined Worlds Equipment: Mini data loggers Equipment: PICAXE-18M2 data logger Books: Engineering: A Very Short Introduction and To Engineer Is Human Book: Soap, Science, & Flat-Screen TVs Equipment: uLog and SensorLab Web Watch

    Science.gov (United States)

    2012-07-01

    WE RECOMMEND Data logger Fourier NOVA LINK: data logging and analysis To Engineer is Human Engineering: essays and insights Soap, Science, & Flat-Screen TVs People, politics, business and science overlap uLog sensors and sensor adapter A new addition to the LogIT range offers simplicity and ease of use WORTH A LOOK Imagined Worlds Socio-scientific predictions for the future Mini light data logger and mini temperature data logger Small-scale equipment for schools SensorLab Plus LogIT's supporting software, with extra features HANDLE WITH CARE CAXE110P PICAXE-18M2 data logger Data logger 'on view' but disappoints Engineering: A Very Short Introduction A broad-brush treatment fails to satisfy WEB WATCH Two very different websites for students: advanced physics questions answered and a more general BBC science resource

  12. Methods for Force Analysis of Overconstrained Parallel Mechanisms: A Review

    Science.gov (United States)

    Liu, Wen-Lan; Xu, Yun-Dou; Yao, Jian-Tao; Zhao, Yong-Sheng

    2017-11-01

    The force analysis of overconstrained PMs is relatively complex and difficult, for which the methods have always been a research hotspot. However, few literatures analyze the characteristics and application scopes of the various methods, which is not convenient for researchers and engineers to master and adopt them properly. A review of the methods for force analysis of both passive and active overconstrained PMs is presented. The existing force analysis methods for these two kinds of overconstrained PMs are classified according to their main ideas. Each category is briefly demonstrated and evaluated from such aspects as the calculation amount, the comprehensiveness of considering limbs' deformation, and the existence of explicit expressions of the solutions, which provides an important reference for researchers and engineers to quickly find a suitable method. The similarities and differences between the statically indeterminate problem of passive overconstrained PMs and that of active overconstrained PMs are discussed, and a universal method for these two kinds of overconstrained PMs is pointed out. The existing deficiencies and development directions of the force analysis methods for overconstrained systems are indicated based on the overview.

  13. Raynaud's Phenomenon: a Brief Review of the Underlying Mechanisms

    Directory of Open Access Journals (Sweden)

    Manal Fardoun

    2016-11-01

    Full Text Available Raynaud's phenomenon (RP is characterized by exaggerated cold-induced vasoconstriction. This augmented vasoconstriction occurs by virtue of a reflex response to cooling via the sympathetic nervous system as well as by local activation of α2C adrenoceptors (α2C-AR. In a cold-initiated, mitochondrion-mediated mechanism involving reactive oxygen species and the Rho/ROCK pathway, cytoskeletal rearrangement in vascular smooth muscle cells (VSMCs orchestrates the translocation of α2C-AR to the cell membrane, where this receptor readily interacts with its ligand. Different parameters are involved in this spatial and functional rescue of α2C-AR. Of notable relevance is the female hormone, 17β-estradiol, or estrogen. This is consistent with the high prevalence of RP in pre-menopausal women compared to age-matched males. In addition to dissecting the role of these various players, the contribution of pollution as well as genetic background to the onset and prevalence of RP are also discussed. Different therapeutic approaches employed as treatment modalities for this disease are also highlighted and analyzed. The lack of an appropriate animal model for RP mandates that more efforts be undertaken in order to better understand and eventually treat this disease. Although several lines of treatment are utilized, it is important to note that precaution is often effective in reducing severity or frequency of RP attacks.

  14. Review: Wind impacts on plant growth, mechanics and damage.

    Science.gov (United States)

    Gardiner, Barry; Berry, Peter; Moulia, Bruno

    2016-04-01

    Land plants have adapted to survive under a range of wind climates and this involve changes in chemical composition, physical structure and morphology at all scales from the cell to the whole plant. Under strong winds plants can re-orientate themselves, reconfigure their canopies, or shed needles, leaves and branches in order to reduce the drag. If the wind is too strong the plants oscillate until the roots or stem fail. The mechanisms of root and stem failure are very similar in different plants although the exact details of the failure may be different. Cereals and other herbaceous crops can often recover after wind damage and even woody plants can partially recovery if there is sufficient access to water and nutrients. Wind damage can have major economic impacts on crops, forests and urban trees. This can be reduced by management that is sensitive to the local site and climatic conditions and accounts for the ability of plants to acclimate to their local wind climate. Wind is also a major disturbance in many plant ecosystems and can play a crucial role in plant regeneration and the change of successional stage. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  15. Psychological and neural mechanisms of experimental extinction: a selective review.

    Science.gov (United States)

    Delamater, Andrew R; Westbrook, R Frederick

    2014-02-01

    The present review examines key psychological concepts in the study of experimental extinction and implications these have for an understanding of the underlying neurobiology of extinction learning. We suggest that many of the signature characteristics of extinction learning (spontaneous recovery, renewal, reinstatement, rapid reacquisition) can be accommodated by the standard associative learning theory assumption that extinction results in partial erasure of the original learning together with new inhibitory learning. Moreover, we consider recent behavioral and neural evidence that supports the partial erasure view of extinction, but also note shortcomings in our understanding of extinction circuits as these relate to the negative prediction error concept. Recent work suggests that common prediction error and stimulus-specific prediction error terms both may be required to explain neural plasticity both in acquisition and extinction learning. In addition, we suggest that many issues in the content of extinction learning have not been fully addressed in current research, but that neurobiological approaches should be especially helpful in addressing such issues. These include questions about the nature of extinction learning (excitatory CS-No US, inhibitory CS-US learning, occasion setting processes), especially as this relates to studies of the micro-circuitry of extinction, as well as its representational content (sensory, motivational, response). An additional understudied problem in extinction research is the role played by attention processes and their underlying neural networks, although some research and theory converge on the idea that extinction is accompanied by attention decrements (i.e., habituation-like processes). Copyright © 2013 Elsevier Inc. All rights reserved.

  16. Parameters affecting mechanical and thermal responses in bone drilling: A review.

    Science.gov (United States)

    Lee, JuEun; Chavez, Craig L; Park, Joorok

    2018-04-11

    Surgical bone drilling is performed variously to correct bone fractures, install prosthetics, or for therapeutic treatment. The primary concern in bone drilling is to extract donor bone sections and create receiving holes without damaging the bone tissue either mechanically or thermally. We review current results from experimental and theoretical studies to investigate the parameters related to such effects. This leads to a comprehensive understanding of the mechanical and thermal aspects of bone drilling to reduce their unwanted complications. This review examines the important bone-drilling parameters of bone structure, drill-bit geometry, operating conditions, and material evacuation, and considers the current techniques used in bone drilling. We then analyze the associated mechanical and thermal effects and their contributions to bone-drilling performance. In this review, we identify a favorable range for each parameter to reduce unwanted complications due to mechanical or thermal effects. Copyright © 2018 Elsevier Ltd. All rights reserved.

  17. Review of International Experience with Renewable Energy Obligation Support Mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Wiser, R.

    2005-06-01

    The main policy instruments currently used in the EU Member States to achieve the targets set for electricity produced from renewable energy sources are: (1) the quota obligation system; (2) the feed-in tariff system; and (3) the tendering system. The current study aims to review the experience gained with the quota obligation system. The report provides an overview of the regions where obligation systems have been implemented and contains a detailed evaluation of the performance of the obligation systems in the USA, the UK and in Sweden. The obligation systems in these countries have been evaluated based on the following criteria: Effectiveness; Market efficiency; Certainty for the renewable energy industry; Cost effectiveness; Stakeholder support for the obligation system; and Equity. The evaluation of international experiences with the obligation system gives rise to a mixed picture. Although an obligation in theory is effective and cost effective, it seems too early to conclude that the system delivers these promises in practice. On the one hand this is due to the limited period of implementation that makes it hard to distinguish between the direct effect of the system and some teething problems that will be solved in due time. On the other hand, the conclusion can be drawn that the obligation is a complex system, which will only function well if designed carefully. It does seem worthwhile, however, to continue monitoring the experiences with the obligation system abroad, because this will further reveal whether the system is indeed effective and cost effective in practice. In the longer term, e.g. beyond 2010, the introduction of an obligation system in the Netherlands could be considered. Finally, as the design of support schemes is being improved, it appears that the basic concepts of both the obligation system and the feed in system have been refined in such a way that the two systems are gradually converging. An important difference between the two systems

  18. Practical application of the benchmarking technique to increase reliability and efficiency of power installations and main heat-mechanic equipment of thermal power plants

    Science.gov (United States)

    Rimov, A. A.; Chukanova, T. I.; Trofimov, Yu. V.

    2016-12-01

    facilitating the analysis of the benchmarking results permitting to represent the quality loss of this power installation in the form of the difference between the actual value of the key indicator or comparison indicator and the best quartile of the existing distribution. The uncertainty of the obtained values of the quality loss indicators was evaluated by transforming the standard uncertainties of the input values into the expanded uncertainties of the output values with the confidence level of 95%. The efficiency of the technique is demonstrated in terms of benchmarking of the main thermal and mechanical equipment of the extraction power-generating units T-250 and power installations of the thermal power plants with the main steam pressure 130 atm.

  19. Review on structural fatigue of NiTi shape memory alloys: Pure mechanical and thermo-mechanical ones

    Directory of Open Access Journals (Sweden)

    Guozheng Kang

    2015-11-01

    Full Text Available Structural fatigue of NiTi shape memory alloys is a key issue that should be solved in order to promote their engineering applications and utilize their unique shape memory effect and super-elasticity more sufficiently. In this paper, the latest progresses made in experimental and theoretical analyses for the structural fatigue features of NiTi shape memory alloys are reviewed. First, macroscopic experimental observations to the pure mechanical and thermo-mechanical fatigue features of the alloys are summarized; then the state-of-arts in the mechanism analysis of fatigue rupture are addressed; further, advances in the construction of fatigue failure models are provided; finally, summary and future topics are outlined.

  20. Medical Issues: Equipment

    Science.gov (United States)

    ... Information Packets Equipment Pool Living With SMA Medical Issues Palliative Breathing Orthopedics Nutrition Equipment Daily Life At ... curesma.org > support & care > living with sma > medical issues > equipment Equipment Individuals with SMA often require a ...

  1. Technical note. A review of the mechanical integrity of the canister

    International Nuclear Information System (INIS)

    Segle, Peter

    2012-01-01

    Background: The Swedish Radiation Safety Authority (SSM) reviews the Swedish Nuclear Fuel Company's (SKB) applications under the Act on Nuclear Activities (SFS 1984:3) for the construction and operation of a repository for spent nuclear fuel and for an encapsulation facility. As part of the review, SSM commissions consultants to carry out work in order to obtain information on specific issues. The results from the consultants' tasks are reported in SSM's Technical Note series. Objectives of the project: This project is part of SSM:s review of SKB:s license application for final disposal of spent nuclear fuel. The assignment concerns a review of the mechanical integrity of the canister. Summary by the author: An introductory review of SR-Site has been conducted with respect to the mechanical integrity of the canister. The review is focused on the copper canister and the nodular cast iron insert. Review results show that a number of loads and loading scenarios for the copper canister has not been analysed by SKB. The importance of sufficient creep ductility of the copper material and sufficient ductility and fracture toughness of the nodular cast iron material is pointed out in the review. A sensitivity study is suggested where the impact of these properties on the mechanical integrity of the canister is investigated. It is also suggested that potential damage mechanisms influencing these properties are further investigated. SKB's modelling of creep elongation at rupture under repository conditions is questioned. Needs for complementary information from SKB for the main review of SR-Site is listed. A list of review topics for SSM is also suggested

  2. Semiconductor Manufacturing equipment introduction

    International Nuclear Information System (INIS)

    Im, Jong Sun

    2001-02-01

    This book deals with semiconductor manufacturing equipment. It is comprised of nine chapters, which are manufacturing process of semiconductor device, history of semiconductor manufacturing equipment, kinds and role of semiconductor manufacturing equipment, construction and method of semiconductor manufacturing equipment, introduction of various semiconductor manufacturing equipment, spots of semiconductor manufacturing, technical elements of semiconductor manufacturing equipment, road map of technology of semiconductor manufacturing equipment and semiconductor manufacturing equipment in the 21st century.

  3. Endocrine-disrupting Chemicals: Review of Toxicological Mechanisms Using Molecular Pathway Analysis

    Science.gov (United States)

    Yang, Oneyeol; Kim, Hye Lim; Weon, Jong-Il; Seo, Young Rok

    2015-01-01

    Endocrine disruptors are known to cause harmful effects to human through various exposure routes. These chemicals mainly appear to interfere with the endocrine or hormone systems. As importantly, numerous studies have demonstrated that the accumulation of endocrine disruptors can induce fatal disorders including obesity and cancer. Using diverse biological tools, the potential molecular mechanisms related with these diseases by exposure of endocrine disruptors. Recently, pathway analysis, a bioinformatics tool, is being widely used to predict the potential mechanism or biological network of certain chemicals. In this review, we initially summarize the major molecular mechanisms involved in the induction of the above mentioned diseases by endocrine disruptors. Additionally, we provide the potential markers and signaling mechanisms discovered via pathway analysis under exposure to representative endocrine disruptors, bisphenol, diethylhexylphthalate, and nonylphenol. The review emphasizes the importance of pathway analysis using bioinformatics to finding the specific mechanisms of toxic chemicals, including endocrine disruptors. PMID:25853100

  4. Guide to optimized replacement of equipment seals

    International Nuclear Information System (INIS)

    Gleason, J.F.

    1990-03-01

    A reevaluation of current scheduled replacement intervals of polymeric seals in plant equipment can achieve significant benefits. Information is provided which has the potential for increasing replacement intervals based on better information on how seals have performed through unique nuclear industry tests to qualify equipment, improved elastomers and increased knowledge of the failure mechanisms and related performance. The research was performed by reviewing applications of elastomeric seals in nuclear plants and practice associated with defining seal replacement intervals in the nuclear power and other industries. Performance indicators and how they predict degradation of seals were evaluated. Guidelines and a flow chart for reevaluating seal replacement intervals are provided. 29 refs., 38 figs., 8 tabs

  5. The meridian system and mechanism of acupuncture: a comparative review. Part 3: Mechanisms of acupuncture therapies.

    Science.gov (United States)

    Chang, Shyang

    2013-06-01

    The human body is a hierarchical organism containing many levels of mutually interacting oscillatory systems. From the viewpoint of traditional Chinese medicine, health is a state of harmony emergent from the interactions of these systems and disease is a state of discord. Hence, human diseases are considered as disturbed functions rather than changed structures. Indeed, the change from normal to abnormal structure may be beneficent rather than maleficent. For example, when one kidney becomes twice the normal size following the destruction of the other kidney, it is good and not bad for us because we might be dead otherwise. Therefore, in Part 3 of this three-part series, emphasis is mainly laid on the acupuncture mechanisms of treating disturbed physiological functions rather than disordered structures. At first, the basic tenets of conventional neuroscience and cardiology are reevaluated so that clear understanding of how nervous and cardiovascular systems work together can be obtained. Then, the general principles of diagnosis and treatment in traditional Chinese medicine from the integrative perspective of complex dynamic systems are proposed. Finally, mechanisms of acupuncture therapies for treating 14 different categories of disorders will be elucidated via the magneto-electric inductive effects of the meridian system. Copyright © 2013. Published by Elsevier B.V.

  6. A review of protective factors and causal mechanisms that enhance the mental health of Indigenous Circumpolar youth

    OpenAIRE

    Petrasek MacDonald, Joanna; Ford, James D.; Cunsolo Willox, Ashlee; Ross, Nancy A.

    2013-01-01

    Objectives To review the protective factors and causal mechanisms which promote and enhance Indigenous youth mental health in the Circumpolar North. Study design A systematic literature review of peer-reviewed English-language research was conducted to systematically examine the protective factors and causal mechanisms which promote and enhance Indigenous youth mental health in the Circumpolar North. Methods This review followed the Preferred Reporting Items for Systematic Reviews and Meta-An...

  7. Standard Review Plan for the review of financial assurance mechanisms for decommissioning under 10 CFR Parts 30, 40, 70, and 72

    International Nuclear Information System (INIS)

    1989-08-01

    Standard Review Plan (SRP) for the Review of Financial Assurance Mechanisms for Decommissioning under 10 CFR Parts 30, 40, 70 and 72, is prepared for the guidance of Nuclear Regulatory Commission staff reviewers in performing reviews of applications from material licensees affected by the decommissioning regulations established June 27, 1988 (53FR24018). The principal purpose of the SRP is to assure the quality and uniformity of staff reviews and to present a base from which to evaluate the financial assurance aspects of the applications. The SRP identifies who performs the review, the matters that are reviewed, the basis for the review, how the review is performed, and the conclusions that are sought

  8. Support motions for mechanical components during earthquakes

    International Nuclear Information System (INIS)

    Hadjian, A.H.

    1979-01-01

    The functioning of mechanical and other equipment during and after earthquakes may not only be necessary to avoid catastrophic consequences, such as in nuclear facilities, but also to guarantee the adequate functioning of emergency facilities (hospitals and fire stations, for example) that are necessary to cope with the aftermath of an earthquake. The state-of-the-art methods used for prescribing support motions to equipment in structures is reviewed from the elementary to the more complex. Also reviewed are the justifications for the uncoupling of the equipment from the structure for purposes of analysis, and the impacts that uncertainties in the total process may have on equipment design. (author)

  9. Scientific Equipment Division - Overview

    International Nuclear Information System (INIS)

    Halik, J.

    2001-01-01

    Full text: The Scientific Equipment Division consists of the Design Group and the Mechanical Workshop. The activity of the Division includes the following: - designing of devices and equipment for experiments in physics, their mechanical construction and assembly. In particular, there are vacuum chambers and installations for HV and UHV; - maintenance and upgrading of the existing installations and equipment in our Institute; - participation of our engineers and technicians in design works, equipment assembly and maintenance for experiments in foreign laboratories. The Design Group is equipped with PC-computers and AutoCAD graphic software (release 2000 and Mechanical Desktop 4.0) and a AO plotter, what allows us to make drawings and 2- and 3-dimensional mechanical documentation to the world standards. The Mechanical Workshop can offer a wide range of machining and treatment methods with satisfactory tolerances and surface quality. It offers the following possibilities: - turning - cylindrical elements of a length up to 2000 mm and a diameter up to 400 mm, and also disc-type elements of a diameter up to 600 mm and a length not exceeding 300 mm; - milling - elements of length up to 1000 mm and gear wheels of diameter up to 300 mm; - grinding - flat surfaces of dimensions up to 300 mm x 1000 mm and cylindrical elements of a diameter up to 200 mm and a length up to 800 mm; - drilling - holes of a diameter up to 50 mm; - welding - electrical and gas welding, including TIG vacuum-tight welding; - soft and hard soldering; - mechanical works including precision engineering; - plastics treatment - machining and polishing using diamond milling, modelling, lamination of various shapes and materials, including plexiglas, scintillators and light-guides; - painting - paint spraying with possibility of using furnace-fred drier of internal dimensions of 800 mm x 800 mm x 800 mm. Our workshop posses CNC milling machine which can be used for machining of work-pieces up to 500 kg

  10. APPLIED MECHANICS REVIEWS, WADEX WORD AND AUTHOR INDEX, VOLUME XVI, 1963,

    Science.gov (United States)

    Author inDEX ) an IBM 1401 prepared mechanical index, extension of KWIC. WADEX usable for browsing and searching. This second WADEX is based on 8,000 titles of APPLIED MECHANICS REVIEWS (AMR), Vol. 16, 1963, an international critical review magazine. In WADEX, titles printed fully with author names, and as many lines used as necessary (60 characters per line). WADEX entry: word in title (except forbidden word) or author’s name. Alphabetically sequenced entries printed out of context. Words are single words or hypenated word pairs or ’Tagged Words’ (TW).

  11. The meridian system and mechanism of acupuncture—A comparative review. Part 1: The meridian system

    Directory of Open Access Journals (Sweden)

    Shyang Chang

    2012-12-01

    Full Text Available In traditional Chinese medicine (TCM, acupuncture has been used to heal various diseases and physiologic malfunctions in clinical practice for more than 2500 years. Due to its efficacy, acupuncture has been recommended by the World Health Organization in 1980 as an effective alternative therapy for 43 different disorders. Over the past few decades, various theories of the meridian system and mechanisms have been proposed to explain how acupuncture might work. Most of these mechanisms, however, cannot yet explain conclusively why acupuncture is efficacious in treating so many different diseases. A plausible mechanism has been unavailable until recently. This is the first of a three-part series that aims to provide a comparative review of the aforementioned topics. Part 1 reviews the current indications for acupuncture, basic concepts of TCM, and the essence of the meridian system. To establish a mathematically rigorous framework of TCM, the chaotic wave theory of fractal continuum is proposed. This theory is then applied to characterize the essence of the meridian system. Parts 2 and 3 will review the possible mechanisms of acupuncture analgesia and acupuncture therapies, respectively, based on biochemical, bioelectromagnetic, chaotic wave, and neurophysiologic approaches. It is sincerely hoped that this series of review articles can promote an understanding of the meridian system and acupuncture mechanisms to help patients in a logical and passionate way.

  12. [Equipment and technology in robotics].

    Science.gov (United States)

    Murphy, Declan; Challacombe, Ben; Nedas, Tim; Elhage, Oussama; Althoefer, Kaspar; Seneviratne, Lakmal; Dasgupta, Prokar

    2007-05-01

    We review the evolution and current status of robotic equipment and technology in urology. We also describe future developments in the key areas of virtual reality simulation, mechatronics and nanorobotics. The history of robotic technology is reviewed and put into the context of current systems. Experts in the associated fields of nanorobotics, mechatronics and virtual reality simulation simulation review the important future developments in these areas.

  13. The Role of Malware in Reported Cyber Espionage: A Review of the Impact and Mechanism

    OpenAIRE

    Gaute Wangen

    2015-01-01

    This is the journal's PDF originally published in Information, http://dx.doi.org/10.3390/info6020183 The recent emergence of the targeted use of malware in cyber espionage versus industry requires a systematic review for better understanding of its impact and mechanism. This paper proposes a basic taxonomy to document major cyber espionage incidents, describing and comparing their impacts (geographic or political targets, origins and motivations) and their mechanisms (dropper, propagation,...

  14. Concise review: Bone marrow for the treatment of spinal cord injury: mechanisms and clinical applications.

    OpenAIRE

    Wright, KT; El Masri, W; Osman, A; Chowdhury, J; Johnson, WEB

    2011-01-01

    Transplantation of bone marrow stem cells into spinal cord lesions enhances axonal regeneration and promotes functional recovery in animal studies. There are two types of adult bone marrow stem cell; hematopoietic stem cells (HSCs), and mesenchymal stem cells (MSCs). The mechanisms by which HSCs and MSCs might promote spinal cord repair following transplantation have been extensively investigated. The objective of this review is to discuss these mechanisms; we briefly consider the controversi...

  15. Qualification of electrical equipment. A United States nuclear system supplier perspective

    International Nuclear Information System (INIS)

    Jordan, W.G.

    1978-01-01

    At Westinghouse Pressurized Water Reactor Systems Division (PWR-SD) qualification. of safety related electrical equipment can be segregated into three distinct generations: (1) the initial seismic and environmental qualification programs for electrical equipment (1969-1972); (2) the supplemental sismic and environmental qualification programs (1975-1977); and (3) the seismic and environmental qualification programs to meet IEEE-323-1974, IEEE Standard for Qualifying Class 1E Equipment for Nuclear Power Generating Stations''(1975). The latter two programs (in a licensing framework), as they are most current, with emphasis on electrical equipment (e.g. transmitters, rack mounted equipment) as opposed to electro-mechanical equipment (valve operators, pump motors) are reviewed. (author)

  16. Review of collapse triggering mechanism of collapsible soils due to wetting

    Directory of Open Access Journals (Sweden)

    Ping Li

    2016-04-01

    Full Text Available Loess soil deposits are widely distributed in arid and semi-arid regions and constitute about 10% of land area of the world. These soils typically have a loose honeycomb-type meta-stable structure that is susceptible to a large reduction in total volume or collapse upon wetting. Collapse characteristics contribute to various problems to infrastructures that are constructed on loess soils. For this reason, collapse triggering mechanism for loess soils has been of significant interest for researchers and practitioners all over the world. This paper aims at providing a state-of-the-art review on collapse mechanism with special reference to loess soil deposits. The collapse mechanism studies are summarized under three different categories, i.e. traditional approaches, microstructure approach, and soil mechanics-based approaches. The traditional and microstructure approaches for interpreting the collapse behavior are comprehensively summarized and critically reviewed based on the experimental results from the literature. The soil mechanics-based approaches proposed based on the experimental results of both compacted soils and natural loess soils are reviewed highlighting their strengths and limitations for estimating the collapse behavior. Simpler soil mechanics-based approaches with less parameters or parameters that are easy-to-determine from conventional tests are suggested for future research to better understand the collapse behavior of natural loess soils. Such studies would be more valuable for use in conventional geotechnical engineering practice applications.

  17. BOOK REVIEW: Advanced Mechanics and General Relativity Advanced Mechanics and General Relativity

    Science.gov (United States)

    Louko, Jorma

    2011-04-01

    Joel Franklin's textbook `Advanced Mechanics and General Relativity' comprises two partially overlapping, partially complementary introductory paths into general relativity at advanced undergraduate level. Path I starts with the Lagrangian and Hamiltonian formulations of Newtonian point particle motion, emphasising the action principle and the connection between symmetries and conservation laws. The concepts are then adapted to point particle motion in Minkowski space, introducing Lorentz transformations as symmetries of the action. There follows a focused development of tensor calculus, parallel transport and curvature, using examples from Newtonian mechanics and special relativity, culminating in the field equations of general relativity. The Schwarzschild solution is analysed, including a detailed discussion of the tidal forces on a radially infalling observer. Basics of gravitational radiation are examined, highlighting the similarities to and differences from electromagnetic radiation. The final topics in Path I are equatorial geodesics in Kerr and the motion of a relativistic string in Minkowski space. Path II starts by introducing scalar field theory on Minkowski space as a limit of point masses connected by springs, emphasising the action principle, conservation laws and the energy-momentum tensor. The action principle for electromagnetism is introduced, and the coupling of electromagnetism to a complex scalar field is developed in a detailed and pedagogical fashion. A free symmetric second-rank tensor field on Minkowski space is introduced, and the action principle of general relativity is recovered from coupling the second-rank tensor to its own energy-momentum tensor. Path II then merges with Path I and, supplanted with judicious early selections from Path I, can proceed to the Schwarzschild solution. The choice of material in each path is logical and focused. A notable example in Path I is that Lorentz transformations in Minkowki space are introduced

  18. Commissioning and maintenance experience on mechanical equipment in steam generators of captive power plant at HWP, Manuguru (Paper No. 5.3)

    International Nuclear Information System (INIS)

    Bhatnagar, R.; Sinha, Ashok; Mohan Rao, A.C.

    1992-01-01

    Heavy Water Project (Manuguru) is having a captive power plant to cater to the demands of steam and power for the main plant. During the commissioning and initial run of the steam generators and their auxiliaries, teething/initial problems were encountered in nearly all the equipment of the steam generators. This paper briefly describes some of the major problems faced during the commissioning of the steam generators. (author). 4 figs

  19. Reviews Book: Enjoyable Physics Equipment: SEP Colorimeter Box Book: Pursuing Power and Light Equipment: SEP Bottle Rocket Launcher Equipment: Sciencescope GLE Datalogger Equipment: EDU Logger Book: Physics of Sailing Book: The Lightness of Being Software: Logotron Insight iLog Studio iPhone Apps Lecture: 2010 IOP Schools and Colleges Lecture Web Watch

    Science.gov (United States)

    2010-09-01

    WE RECOMMEND Enjoyable Physics Mechanics book makes learning more fun SEP Colorimeter Box A useful and inexpensive colorimeter for the classroom Pursuing Power and Light Account of the development of science in the 19th centuary SEP Bottle Rocket Launcher An excellent resource for teaching about projectiles GLE Datalogger GPS software is combined with a datalogger EDU Logger Remote datalogger has greater sensing abilities Logotron Insight iLog Studio Software enables datlogging, data analysis and modelling iPhone Apps Mobile phone games aid study of gravity WORTH A LOOK Physics of Sailing Book journeys through the importance of physics in sailing The Lightness of Being Study of what the world is made from LECTURE The 2010 IOP Schools and Colleges Lecture presents the physics of fusion WEB WATCH Planet Scicast pushes boundaries of pupil creativity

  20. TOPICAL REVIEW: Black silicon method X: a review on high speed and selective plasma etching of silicon with profile control: an in-depth comparison between Bosch and cryostat DRIE processes as a roadmap to next generation equipment

    Science.gov (United States)

    Jansen, H V; de Boer, M J; Unnikrishnan, S; Louwerse, M C; Elwenspoek, M C

    2009-03-01

    impact (due to metallic masks and/or exposed silicon) are the main sources of heat that might raise the wafer temperature uncontrollably, and they show the weakness of the helium backside technique using mechanical clamping. Electrostatic clamping, an alternative technique, should minimize this problem because it is less susceptible to heat transfer when its thermal resistance and the gap of the helium backside cavity are minimized; however, it is not a subject of the current study. Because oxygen-growth-based etch processes (due to their ultra thin inhibiting layer) rely more heavily on a constant wafer temperature than fluorocarbon-based processes, oxygen etches are more affected by temperature fluctuations and drifts during the etching. The fourth outcome of this review is a phenomenological model, which explains and predicts many features with respect to loading, flow and pressure behaviour in DRIE equipment including a diffusion zone. The model is a reshape of the flow model constructed by Mogab, who studied the loading effect in plasma etching. Despite the downside of needing a cryostat, it is shown that—when selecting proper conditions—a cryogenic two-step pulsed mode can be used as a successful technique to achieve high speed and selective plasma etching with an etch rate around 25 µm min-1 (selectivity beyond 1000. With the model in hand, it can be predicted that the etch rate can be doubled (50 µm min-1 at an efficiency of 33% for the fluorine generation from the SF6 feed gas) by minimizing the time the free radicals need to pass the diffusion zone. It is anticipated that this residence time can be reduced sufficiently by a proper inductive coupled plasma (ICP) source design (e.g. plasma shower head and concentrator). In order to preserve the correct profile at such high etch rates, the pressure during the bottom removal step should be minimized and, therefore, the synchronized three-step pulsed mode is believed to be essential to reach such high etch

  1. Atomic Force Microscopy in Characterizing Cell Mechanics for Biomedical Applications: A Review.

    Science.gov (United States)

    Li, Mi; Dang, Dan; Liu, Lianqing; Xi, Ning; Wang, Yuechao

    2017-09-01

    Cell mechanics is a novel label-free biomarker for indicating cell states and pathological changes. The advent of atomic force microscopy (AFM) provides a powerful tool for quantifying the mechanical properties of single living cells in aqueous conditions. The wide use of AFM in characterizing cell mechanics in the past two decades has yielded remarkable novel insights in understanding the development and progression of certain diseases, such as cancer, showing the huge potential of cell mechanics for practical applications in the field of biomedicine. In this paper, we reviewed the utilization of AFM to characterize cell mechanics. First, the principle and method of AFM single-cell mechanical analysis was presented, along with the mechanical responses of cells to representative external stimuli measured by AFM. Next, the unique changes of cell mechanics in two types of physiological processes (stem cell differentiation, cancer metastasis) revealed by AFM were summarized. After that, the molecular mechanisms guiding cell mechanics were analyzed. Finally the challenges and future directions were discussed.

  2. Schizophrenia and depression: A systematic review of the effectiveness and the working mechanisms behind acupuncture

    NARCIS (Netherlands)

    Bosch, M.P.C.; Noort, M.W.M.L. van den; Staudte, H.; Lim, S.

    2015-01-01

    OBJECTIVE: This systematic review assessed clinical evidence for the use of acupuncture as an add-on treatment in patients with depression and schizophrenia and for its underlying working mechanisms. DATA SOURCES: Four databases (Medline, Scopus, ERIC, and the Cochrane Library) were searched with a

  3. Respiratory Care year in review 2013: airway management, noninvasive monitoring, and invasive mechanical ventilation.

    Science.gov (United States)

    Durbin, Charles G; Blanch, Lluís; Fan, Eddy; Hess, Dean R

    2014-04-01

    Fundamental to respiratory care practice are airway management, noninvasive monitoring, and invasive mechanical ventilation. The purpose of this paper is to review the recent literature related to these topics in a manner that is most likely to have interest to the readers of Respiratory Care.

  4. Tutorial review of spent-fuel degradation mechanisms under dry-storage conditions

    International Nuclear Information System (INIS)

    Einziger, R.E.

    1983-02-01

    This tutorial reviews our present understanding of fuel-rod degradation over a range of possible dry-storage environments. Three areas are covered: (1) why study fuel-rod degradation; (2) cladding-degradation mechanisms; and (3) the status of fuel-oxidation studies

  5. Chronic post-thoracotomy pain: a critical review of pathogenic mechanisms and strategies for prevention

    DEFF Research Database (Denmark)

    Wildgaard, Kim; Ravn, Jesper; Kehlet, Henrik

    2009-01-01

    Chronic pain complaints after thoracic surgery represent a significant clinical problem in 25-60% of patients. Results from thoracic and other surgical procedures suggest multiple pathogenic mechanisms that include pre-, intra-, and postoperative factors. This review attempts to analyse the metho...

  6. Order information coding in working memory: Review of behavioural studies and cognitive mechanisms

    Directory of Open Access Journals (Sweden)

    Barbara Dolenc

    2014-06-01

    Full Text Available Executive processes, such as coding for sequential order, are of extreme importance for higher-order cognitive tasks. One of the significant questions is, how order information is coded in working memory and what cognitive mechanisms and processes mediate it. The aim of this review paper is to summarize results of studies that explore whether order and item memory are two separable processes. Furthermore, we reviewed evidence for each of the proposed cognitive mechanism that might mediate order processing. Previous behavioural and neuroimaging data suggest different representation and processing of item and order information in working memory. Both information are maintained and recalled separately and this separation seems to hold for recognition as well as for recall. To explain the result of studies of order coding, numerous cognitive mechanisms were proposed. We focused on four different mechanisms by which order information might be coded and retrieved, namely inter-item associations, direct coding, hierarchical coding and magnitude coding. Each of the mechanisms can explain some of the aspect of order information coding, however none of them is able to explain all of the empirical findings. Due to its complex nature it is not surprising that a single mechanism has difficulties accounting for all the behavioral data and order memory may be more accurately characterized as the result of a set of mechanisms rather than a single one. Moreover, the findings beget a question of whether different types of memory for order information might exist.

  7. Modified Continuum Mechanics Modeling on Size-Dependent Properties of Piezoelectric Nanomaterials: A Review

    Directory of Open Access Journals (Sweden)

    Zhi Yan

    2017-01-01

    Full Text Available Piezoelectric nanomaterials (PNs are attractive for applications including sensing, actuating, energy harvesting, among others in nano-electro-mechanical-systems (NEMS because of their excellent electromechanical coupling, mechanical and physical properties. However, the properties of PNs do not coincide with their bulk counterparts and depend on the particular size. A large amount of efforts have been devoted to studying the size-dependent properties of PNs by using experimental characterization, atomistic simulation and continuum mechanics modeling with the consideration of the scale features of the nanomaterials. This paper reviews the recent progresses and achievements in the research on the continuum mechanics modeling of the size-dependent mechanical and physical properties of PNs. We start from the fundamentals of the modified continuum mechanics models for PNs, including the theories of surface piezoelectricity, flexoelectricity and non-local piezoelectricity, with the introduction of the modified piezoelectric beam and plate models particularly for nanostructured piezoelectric materials with certain configurations. Then, we give a review on the investigation of the size-dependent properties of PNs by using the modified continuum mechanics models, such as the electromechanical coupling, bending, vibration, buckling, wave propagation and dynamic characteristics. Finally, analytical modeling and analysis of nanoscale actuators and energy harvesters based on piezoelectric nanostructures are presented.

  8. Modified Continuum Mechanics Modeling on Size-Dependent Properties of Piezoelectric Nanomaterials: A Review.

    Science.gov (United States)

    Yan, Zhi; Jiang, Liying

    2017-01-26

    Piezoelectric nanomaterials (PNs) are attractive for applications including sensing, actuating, energy harvesting, among others in nano-electro-mechanical-systems (NEMS) because of their excellent electromechanical coupling, mechanical and physical properties. However, the properties of PNs do not coincide with their bulk counterparts and depend on the particular size. A large amount of efforts have been devoted to studying the size-dependent properties of PNs by using experimental characterization, atomistic simulation and continuum mechanics modeling with the consideration of the scale features of the nanomaterials. This paper reviews the recent progresses and achievements in the research on the continuum mechanics modeling of the size-dependent mechanical and physical properties of PNs. We start from the fundamentals of the modified continuum mechanics models for PNs, including the theories of surface piezoelectricity, flexoelectricity and non-local piezoelectricity, with the introduction of the modified piezoelectric beam and plate models particularly for nanostructured piezoelectric materials with certain configurations. Then, we give a review on the investigation of the size-dependent properties of PNs by using the modified continuum mechanics models, such as the electromechanical coupling, bending, vibration, buckling, wave propagation and dynamic characteristics. Finally, analytical modeling and analysis of nanoscale actuators and energy harvesters based on piezoelectric nanostructures are presented.

  9. Interfacial mechanisms of heterogeneous Fenton reactions catalyzed by iron-based materials: A review.

    Science.gov (United States)

    He, Jie; Yang, Xiaofang; Men, Bin; Wang, Dongsheng

    2016-01-01

    The heterogeneous Fenton reaction can generate highly reactive hydroxyl radicals (OH) from reactions between recyclable solid catalysts and H2O2 at acidic or even circumneutral pH. Hence, it can effectively oxidize refractory organics in water or soils and has become a promising environmentally friendly treatment technology. Due to the complex reaction system, the mechanism behind heterogeneous Fenton reactions remains unresolved but fascinating, and is crucial for understanding Fenton chemistry and the development and application of efficient heterogeneous Fenton technologies. Iron-based materials usually possess high catalytic activity, low cost, negligible toxicity and easy recovery, and are a superior type of heterogeneous Fenton catalysts. Therefore, this article reviews the fundamental but important interfacial mechanisms of heterogeneous Fenton reactions catalyzed by iron-based materials. OH, hydroperoxyl radicals/superoxide anions (HO2/O2(-)) and high-valent iron are the three main types of reactive oxygen species (ROS), with different oxidation reactivity and selectivity. Based on the mechanisms of ROS generation, the interfacial mechanisms of heterogeneous Fenton systems can be classified as the homogeneous Fenton mechanism induced by surface-leached iron, the heterogeneous catalysis mechanism, and the heterogeneous reaction-induced homogeneous mechanism. Different heterogeneous Fenton systems catalyzed by characteristic iron-based materials are comprehensively reviewed. Finally, related future research directions are also suggested. Copyright © 2015. Published by Elsevier B.V.

  10. Potential mechanisms linking probiotics to diabetes: a narrative review of the literature

    Directory of Open Access Journals (Sweden)

    Maryam Miraghajani

    Full Text Available ABSTRACT CONTEXT AND OBJECTIVE: Some studies have suggested a wide range of possible mechanisms through which probiotics may play a role in diabetes prevention and treatment. However, the underlying mechanisms are not fully understood. We conducted this study to review the potential mechanisms suggested for the effect of probiotics in diabetes. DESIGN AND SETTING: Narrative review conducted at the Food Security Research Center of Isfahan. METHODS: A search in the electronic databases MEDLINE (PubMed, Cochrane Library, Web of Science and Google scholar was performed up to October 2016. RESULTS: The initial search yielded 1214 reports. After removing duplicates, 704 titles and abstracts were screened. Finally, out of 83 full-text articles that were reviewed for eligibility, 30 articles were included in the final analysis. The anti-diabetic mechanisms for probiotics reported encompass intraluminal and direct effects on the intestinal mucosa and microbiota (n = 13, anti-inflammatory and immunomodulatory effects (n = 10, antioxidative effects (n = 5, effects on endoplasmic reticulum (ER stress and expression of genes involved in glucose homeostasis and insulin resistance (n = 6, with some studies pointing to more than one mechanism. CONCLUSION: The results may throw some light on the capacity of probiotics as a novel approach towards controlling diabetes. However, further human studies are warranted to elucidate and confirm the potential role of probiotics in diabetes prevention and treatment. Also, it needs to be ascertained whether the effectiveness of probiotics in diabetes prevention and treatment is dependent on the strain of the microorganisms.

  11. Mechanism change in a simulation of peer review: from junk support to elitism.

    Science.gov (United States)

    Paolucci, Mario; Grimaldo, Francisco

    2014-01-01

    Peer review works as the hinge of the scientific process, mediating between research and the awareness/acceptance of its results. While it might seem obvious that science would regulate itself scientifically, the consensus on peer review is eroding; a deeper understanding of its workings and potential alternatives is sorely needed. Employing a theoretical approach supported by agent-based simulation, we examined computational models of peer review, performing what we propose to call redesign , that is, the replication of simulations using different mechanisms . Here, we show that we are able to obtain the high sensitivity to rational cheating that is present in literature. In addition, we also show how this result appears to be fragile against small variations in mechanisms. Therefore, we argue that exploration of the parameter space is not enough if we want to support theoretical statements with simulation, and that exploration at the level of mechanisms is needed. These findings also support prudence in the application of simulation results based on single mechanisms, and endorse the use of complex agent platforms that encourage experimentation of diverse mechanisms.

  12. Review of thermodinamic and mechanical properties of hydrogen-transition metal systems

    International Nuclear Information System (INIS)

    Mathias, H.; Katz, Y.

    1978-04-01

    A large body of fundamental and empirical knowledge has been acquired during many years of research concerning the interactions between hydrogen and metals, the location of hydrogen in metal structures, its mobility in metals and its influence on mechanical properties of metals. Much progress has been made in the understanding of related phenomena, and various theories have been proposed, but considerable disagreement still exist about basic mechanisms involved. The growing interest in these subjects and their important role in science and technology are well documented by many reviews and symposia. A general survey of these topics with reference to experimental results and theories related to thermodynamic and mechanical properties of hydrogen-transition metal systems, such as H-Pd, H-Ti, H-Fe etc. is given in the present review. Special emphasis is given to hydrogen embrittlement of metals

  13. Regulatory mechanisms for absenteeism in the health sector: a systematic review of strategies and their implementation.

    Science.gov (United States)

    Kisakye, Angela N; Tweheyo, Raymond; Ssengooba, Freddie; Pariyo, George W; Rutebemberwa, Elizeus; Kiwanuka, Suzanne N

    2016-01-01

    A systematic review was undertaken to identify regulatory mechanisms aimed at mitigating health care worker absenteeism, to describe where and how they have been implemented as well as their possible effects. The goal was to propose potential policy options for managing the problem of absenteeism among human resources for health in low- and middle-income countries. Mechanisms described in this review are at the local workplace and broader national policy level. A comprehensive online search was conducted on EMBASE, CINAHL, PubMed, Google Scholar, Google, and Social Science Citation Index using MEDLINE search terms. Retrieved studies were uploaded onto reference manager and screened by two independent reviewers. Only publications in English were included. Data were extracted and synthesized according to the objectives of the review. Twenty six of the 4,975 published articles retrieved were included. All were from high-income countries and covered all cadres of health workers. The regulatory mechanisms and possible effects include 1) organizational-level mechanisms being reported as effective in curbing absenteeism in low- and middle-income countries (LMICs); 2) prohibition of private sector activities in LMICs offering benefits but presenting a challenge for the government to monitor the health workforce; 3) contractual changes from temporary to fixed posts having been associated with no reduction in absenteeism and not being appropriate for LMICs; 4) multifaceted work interventions being implemented in most settings; 5) the possibility of using financial and incentive regulatory mechanisms in LMICs; 6) health intervention mechanisms reducing absenteeism when integrated with exercise programs; and 7) attendance by legislation during emergencies being criticized for violating human rights in the United States and not being effective in curbing absenteeism. Most countries have applied multiple strategies to mitigate health care worker absenteeism. The success of these

  14. Regulatory mechanisms for absenteeism in the health sector: a systematic review of strategies and their implementation

    Science.gov (United States)

    Kisakye, Angela N; Tweheyo, Raymond; Ssengooba, Freddie; Pariyo, George W; Rutebemberwa, Elizeus; Kiwanuka, Suzanne N

    2016-01-01

    Background A systematic review was undertaken to identify regulatory mechanisms aimed at mitigating health care worker absenteeism, to describe where and how they have been implemented as well as their possible effects. The goal was to propose potential policy options for managing the problem of absenteeism among human resources for health in low- and middle-income countries. Mechanisms described in this review are at the local workplace and broader national policy level. Methods A comprehensive online search was conducted on EMBASE, CINAHL, PubMed, Google Scholar, Google, and Social Science Citation Index using MEDLINE search terms. Retrieved studies were uploaded onto reference manager and screened by two independent reviewers. Only publications in English were included. Data were extracted and synthesized according to the objectives of the review. Results Twenty six of the 4,975 published articles retrieved were included. All were from high-income countries and covered all cadres of health workers. The regulatory mechanisms and possible effects include 1) organizational-level mechanisms being reported as effective in curbing absenteeism in low- and middle-income countries (LMICs); 2) prohibition of private sector activities in LMICs offering benefits but presenting a challenge for the government to monitor the health workforce; 3) contractual changes from temporary to fixed posts having been associated with no reduction in absenteeism and not being appropriate for LMICs; 4) multifaceted work interventions being implemented in most settings; 5) the possibility of using financial and incentive regulatory mechanisms in LMICs; 6) health intervention mechanisms reducing absenteeism when integrated with exercise programs; and 7) attendance by legislation during emergencies being criticized for violating human rights in the United States and not being effective in curbing absenteeism. Conclusion Most countries have applied multiple strategies to mitigate health care

  15. Improvement suggestions on license extension management for civil nuclear safety equipment activities

    International Nuclear Information System (INIS)

    Sun Xingjian; Liu Hongji; Han Guoli; Jia Fengcai

    2013-01-01

    Based on the concepts of Clear Requirements, Comprehensive Review, Objective Assessment, Dynamic Management, this paper gives improvement suggestions on license extension management for civil nuclear safety equipment design, manufacture, installation and non-destructive examination activities, which include establishing a relatively unified license extension review standard, combining multi-views and close linking license review and supervision, full utilizing the daily supervision and inspection results, as well as further improving motivation and elimination mechanism. (authors)

  16. Cellular and Molecular Mechanisms in Perioperative Hepatic Protection: A Review of Current Interventions

    Directory of Open Access Journals (Sweden)

    Zahra Talebi

    2017-05-01

    Full Text Available Liver is one of the most important organs needing great concern during the perioperative period. There are a number of different mechanisms that interact with liver cells and might affect their integrity and cell live. Though these mechanisms are not all the same, there is a great common point: all affect the metabolic pathways of the liver. Ischemia, anesthetic drug effects and other perioperative insults may affect the liver. Disturbance in an organ’s blood flow is an inherent part of diverse surgical procedures, which leads to lack of oxygen and nutrient supply. These ischemic periods can be particularly long in case of liver surgeries, such as resection of large hepatic tumors, management of hepatic trauma and liver transplant. Once the blood flow and oxygen supply are restored, the interruption of blood flow affects the oxygen dependent cells in liver, which require mitochondrial oxidative phosphorylation for their metabolism. Molecular mechanisms such as Redox status, ionic interchange disturbances as well as different mediators and cells like KC, SEC, dendritic cells, leukocytes, and lymphocytes, are involved in the process ultimately leading to cell death by apoptosis and necrosis. This review provides an overview on the cellular and molecular mechanisms involved in liver injuries, categorizing these mechanisms in 3 different classes: preoperative mechanisms, intraoperative mechanisms and postoperative mechanisms. Each of them are discussed in a different part of the manuscript

  17. Review of important rock mechanics studies required for underground high level nuclear waste repository program

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, S.; Cho, W. J

    2007-01-15

    Disposal concept adapting room and pillar method, which is a confirmed technique in mining and tunnel construction for long time, has advantages at cost, safety, technical feasibility, flexibility, and international cooperation point of views. Then the important rock mechanics principals and in situ and laboratory tests for understanding the behavior of rock, buffer, and backfill as well as their interactions will be reviewed. The accurate understanding of them is important for developing a safe disposal concept and successful operation of underground repository for permanent disposal of radioactive wastes. First of all, In this study, current status of rock mechanics studies for HLW disposal in foreign countries such as Sweden, USA, Canada, Finland, Japan, and France were reviewed. After then the in situ and laboratory tests for site characterization were summarized. Furthermore, rock mechanics studies required during the whole procedure for the disposal project from repository design to the final closure will be reviewed systematically. This study will help for developing a disposal system including site selection, repository design, operation, maintenance, and closure of a repository in deep underground rock. By introducing the required rock mechanics tests at different stages, it would be helpful from the planning stage to the operation stage of a radioactive waste disposal project.

  18. Review of important rock mechanics studies required for underground high level nuclear waste repository program

    International Nuclear Information System (INIS)

    Kwon, S.; Cho, W. J.

    2007-01-01

    Disposal concept adapting room and pillar method, which is a confirmed technique in mining and tunnel construction for long time, has advantages at cost, safety, technical feasibility, flexibility, and international cooperation point of views. Then the important rock mechanics principals and in situ and laboratory tests for understanding the behavior of rock, buffer, and backfill as well as their interactions will be reviewed. The accurate understanding of them is important for developing a safe disposal concept and successful operation of underground repository for permanent disposal of radioactive wastes. First of all, In this study, current status of rock mechanics studies for HLW disposal in foreign countries such as Sweden, USA, Canada, Finland, Japan, and France were reviewed. After then the in situ and laboratory tests for site characterization were summarized. Furthermore, rock mechanics studies required during the whole procedure for the disposal project from repository design to the final closure will be reviewed systematically. This study will help for developing a disposal system including site selection, repository design, operation, maintenance, and closure of a repository in deep underground rock. By introducing the required rock mechanics tests at different stages, it would be helpful from the planning stage to the operation stage of a radioactive waste disposal project

  19. Identification of mechanisms enabling integrated care for patients with chronic diseases: a literature review

    Directory of Open Access Journals (Sweden)

    Denise van der Klauw

    2014-07-01

    Full Text Available Introduction: Notwithstanding care for chronically ill patients requires a shift towards care that is well coordinated and focused on prevention and self-care, the concept of integrated care lacks specificity and clarity. This article presents a literature review to identify mechanisms for achieving integrated care objectives.Theory and methods: Existing models often present a large variety of dimensions, archetypes and categories of integration without specifying them. Models and programmes describing integrated care for chronic diseases were reviewed. Data were extracted related to objectives and clusters of mechanisms of integration.Results: Thirty-four studies presented four objectives: functional, organisational, professional and service integration. We categorised approaches and interventions to achieve these objectives by strategy and clusters of ‘mechanisms of integration’: degree, patient centredness and normative aspects.Conclusions and discussion: The clarification of mechanisms to achieve objectives of integrated care as presented may be used as starting point for the development and refinement of integrated care programmes, including methodological grounding of their evaluation. Given that most studies reviewed lack both empirical data and descriptions of the methods used, future research needs to close these gaps. Validation of the findings by a large panel of experts is suggested as recommendation to work towards a grounded framework.

  20. Factors influencing efficiency of sliding mechanics to close extraction space: a systematic review.

    Science.gov (United States)

    Barlow, M; Kula, K

    2008-05-01

    To review recent literature to determine strength of clinical evidence concerning the influence of various factors on the efficiency (rate of tooth movement) of closing extraction spaces using sliding mechanics. A comprehensive systematic review on prospective clinical trials. An electronic search (1966-2006) of several databases limiting the searches to English and using several keywords was performed. Also a hand search of five key journals specifically searching for prospective clinical trials relevant to orthodontic space closure using sliding mechanics was completed. Outcome Measure - Rate of tooth movement. Ten prospective clinical trials comparing rates of closure under different variables and focusing only on sliding mechanics were selected for review. Of these ten trials on rate of closure, two compared arch wire variables, seven compared material variables used to apply force, and one examined bracket variables. Other articles which were not prospective clinical trials on sliding mechanics, but containing relevant information were examined and included as background information. CONCLUSION - The results of clinical research support laboratory results that nickel-titanium coil springs produce a more consistent force and a faster rate of closure when compared with active ligatures as a method of force delivery to close extraction space along a continuous arch wire; however, elastomeric chain produces similar rates of closure when compared with nickel-titanium springs. Clinical and laboratory research suggest little advantage of 200 g nickel-titanium springs over 150 g springs. More clinical research is needed in this area.

  1. Massage therapy: understanding the mechanisms of action on blood pressure. A scoping review.

    Science.gov (United States)

    Nelson, Nicole L

    2015-10-01

    Massage therapy (MT) has shown potential in reducing blood pressure (BP); however, the psychophysiological pathways and structures involved in this outcome are unclear. The aims of this scoping review were twofold. (1) To summarize the current knowledge of the mechanisms of action of MT on BP. (2) To highlight the research gaps and challenges that researchers must overcome to further elucidate how MT attenuates BP. A scoping review was conducted to examine the evidence regarding the mechanisms of action of MT on BP. This review included the thematic analysis of 27 publications that considered the influence of MT on BP. Based on this analysis, six potential BP mediating pathways were identified Current theories suggest that MT exerts sympatholytic effects through physiologic and psychological mechanisms, improves hypothalamus-pituitary-adrenocortical axis function, and increases in blood flow, which, in turn, may improve endothelial function. Future study is needed, using more scientifically rigorous methodology, to fully elucidate the mechanism of action of MT. Copyright © 2015 American Society of Hypertension. Published by Elsevier Inc. All rights reserved.

  2. Review of the Mechanisms and Effects of Noninvasive Body Contouring Devices on Cellulite and Subcutaneous Fat

    Science.gov (United States)

    Alizadeh, Zahra; Halabchi, Farzin; Mazaheri, Reza; Abolhasani, Maryam; Tabesh, Mastaneh

    2016-01-01

    Context Today, different kinds of non-invasive body contouring modalities, including cryolipolysis, radiofrequency (RF), low-level laser therapy (LLLT), and high-intensity focused ultrasound (HIFU) are available for reducing the volume of subcutaneous adipose tissue or cellulite. Each procedure has distinct mechanisms for stimulating apoptosis or necrosis adipose tissue. In addition to the mentioned techniques, some investigations are underway for analyzing the efficacy of other techniques such as whole body vibration (WBV) and extracorporeal shockwave therapy (ESWT). In the present review the mechanisms, effects and side effects of the mentioned methods have been discussed. The effect of these devices on cellulite or subcutaneous fat reduction has been assessed. Evidence Acquisition We searched pubmed, google scholar and the cochrane databases for systemic reviews, review articles, meta-analysis and randomized clinical trials up to February 2015. The keywords were subcutaneous fat, cellulite, obesity, noninvasive body contouring, cryolipolysis, RF, LLLT, HIFU, ESWT and WBV with full names and abbreviations. Results We included seven reviews and 66 original articles in the present narrative review. Most of them were applied on normal weight or overweight participants (body mass index cellulite in some body areas. However, the clinical effects are mild to moderate, for example 2 - 4 cm circumference reduction as a sign of subcutaneous fat reduction during total treatment sessions. Overall, there is no definitive noninvasive treatment method for cellulite. Additionally, due to the methodological differences in the existing evidence, comparing the techniques is difficult. PMID:28123436

  3. Mechanical bowel preparation and oral antibiotic prophylaxis in colorectal surgery: Analysis of evidence and narrative review.

    Science.gov (United States)

    Badia, Josep M; Arroyo-García, Nares

    2018-05-14

    The role of oral antibiotic prophylaxis and mechanical bowel preparation in colorectal surgery remains controversial. The lack of efficacy of mechanical preparation to improve infection rates, its adverse effects, and multimodal rehabilitation programs have led to a decline in its use. This review aims to evaluate current evidence on antegrade colonic cleansing combined with oral antibiotics for the prevention of surgical site infections. In experimental studies, oral antibiotics decrease the bacterial inoculum, both in the bowel lumen and surgical field. Clinical studies have shown a reduction in infection rates when oral antibiotic prophylaxis is combined with mechanical preparation. Oral antibiotics alone seem to be effective in reducing infection in observational studies, but their effect is inferior to the combined preparation. In conclusion, the combination of oral antibiotics and mechanical preparation should be considered the gold standard for the prophylaxis of postoperative infections in colorectal surgery. Copyright © 2018 AEC. Publicado por Elsevier España, S.L.U. All rights reserved.

  4. On Finsler Geometry and Applications in Mechanics: Review and New Perspectives

    Directory of Open Access Journals (Sweden)

    J. D. Clayton

    2015-01-01

    direction as well as position, and a number of connections emerge associated with various covariant derivatives involving affine and nonlinear coefficients. Finsler geometry encompasses Riemannian, Euclidean, and Minkowskian geometries as special cases, and thus it affords great generality for describing a number of phenomena in physics. Here, descriptions of finite deformation of continuous media are of primary focus. After a review of necessary mathematical definitions and derivations, prior work involving application of Finsler geometry in continuum mechanics of solids is reviewed. A new theoretical description of continua with microstructure is then outlined, merging concepts from Finsler geometry and phase field theories of materials science.

  5. TiO2-based memristors and ReRAM: materials, mechanisms and models (a review)

    International Nuclear Information System (INIS)

    Gale, Ella

    2014-01-01

    The memristor is the fundamental nonlinear circuit element, with uses in computing and computer memory. Resistive Random Access Memory (ReRAM) is a resistive switching memory proposed as a non-volatile memory. In this review we shall summarize the state of the art for these closely-related fields, concentrating on titanium dioxide, the well-utilized and archetypal material for both. We shall cover material properties, switching mechanisms and models to demonstrate what ReRAM and memristor scientists can learn from each other and examine the outlook for these technologies. (invited review)

  6. Regulatory mechanisms for absenteeism in the health sector: a systematic review of strategies and their implementation

    Directory of Open Access Journals (Sweden)

    Kisakye AN

    2016-11-01

    Full Text Available Angela N Kisakye,1 Raymond Tweheyo,1 Freddie Ssengooba,1 George W Pariyo,2 Elizeus Rutebemberwa,1 Suzanne N Kiwanuka1 1Department of Health Policy Planning and Management, Makerere University School of Public Health, Kampala, Uganda; 2Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA Background: A systematic review was undertaken to identify regulatory mechanisms aimed at mitigating health care worker absenteeism, to describe where and how they have been implemented as well as their possible effects. The goal was to propose potential policy options for managing the problem of absenteeism among human resources for health in low- and middle-income countries. Mechanisms described in this review are at the local workplace and broader national policy level. Methods: A comprehensive online search was conducted on EMBASE, CINAHL, PubMed, Google Scholar, Google, and Social Science Citation Index using MEDLINE search terms. Retrieved studies were uploaded onto reference manager and screened by two independent reviewers. Only publications in English were included. Data were extracted and synthesized according to the objectives of the review. Results: Twenty six of the 4,975 published articles retrieved were included. All were from high-income countries and covered all cadres of health workers. The regulatory mechanisms and possible effects include 1 organizational-level mechanisms being reported as effective in curbing absenteeism in low- and middle-income countries (LMICs; 2 prohibition of private sector activities in LMICs offering benefits but presenting a challenge for the government to monitor the health workforce; 3 contractual changes from temporary to fixed posts having been associated with no reduction in absenteeism and not being appropriate for LMICs; 4 multifaceted work interventions being implemented in most settings; 5 the possibility of using financial and incentive regulatory mechanisms

  7. Education on invasive mechanical ventilation involving intensive care nurses: a systematic review.

    Science.gov (United States)

    Guilhermino, Michelle C; Inder, Kerry J; Sundin, Deborah

    2018-03-26

    Intensive care unit nurses are critical for managing mechanical ventilation. Continuing education is essential in building and maintaining nurses' knowledge and skills, potentially improving patient outcomes. The aim of this study was to determine whether continuing education programmes on invasive mechanical ventilation involving intensive care unit nurses are effective in improving patient outcomes. Five electronic databases were searched from 2001 to 2016 using keywords such as mechanical ventilation, nursing and education. Inclusion criteria were invasive mechanical ventilation continuing education programmes that involved nurses and measured patient outcomes. Primary outcomes were intensive care unit mortality and in-hospital mortality. Secondary outcomes included hospital and intensive care unit length of stay, length of intubation, failed weaning trials, re-intubation incidence, ventilation-associated pneumonia rate and lung-protective ventilator strategies. Studies were excluded if they excluded nurses, patients were ventilated for less than 24 h, the education content focused on protocol implementation or oral care exclusively or the outcomes were participant satisfaction. Quality was assessed by two reviewers using an education intervention critical appraisal worksheet and a risk of bias assessment tool. Data were extracted independently by two reviewers and analysed narratively due to heterogeneity. Twelve studies met the inclusion criteria for full review: 11 pre- and post-intervention observational and 1 quasi-experimental design. Studies reported statistically significant reductions in hospital length of stay, length of intubation, ventilator-associated pneumonia rates, failed weaning trials and improvements in lung-protective ventilation compliance. Non-statistically significant results were reported for in-hospital and intensive care unit mortality, re-intubation and intensive care unit length of stay. Limited evidence of the effectiveness of

  8. A review of penetration mechanisms and dynamic properties of tungsten and depleted uranium penetrators

    International Nuclear Information System (INIS)

    Andrew, S.P.; Caligiuri, R.D.; Eiselstein, L.E.

    1991-01-01

    Over the last decade, depleted uranium (DU) and tungsten alloys have been the materials of choice for kinetic energy penetrators. However, despite improvements in mechanical properties in recent years, the penetration performance of tungsten still lags behind that of DU. One possible reason is the difference in deformation mechanisms- DU alloys tend to shear band as they penetrate the target material, whereas tungsten penetrators tend to mushroom. As a first step to determining whether shear banding is truly the reason for superior DU performance, a review and summary of the available information was performed. This paper presents a state-of-the-art review of the formulation, high strain- rate properties, and penetration phenomena of penetrators manufactured from both tungsten and DU alloys. Specifically, the effects of composition, processing, and heat treatment on mechanical properties and penetration mechanisms of these alloys are discussed. Penetration data and models for penetration mechanisms (in particular shear banding) are also presented, as well as the applicability of these models and their salient features

  9. Using Vector Projection Method to evaluate maintainability of mechanical system in design review

    International Nuclear Information System (INIS)

    Chen Lu; Cai Jianguo

    2003-01-01

    Maintainability of a mechanical system is one of the system design parameters that has a great impact in terms of ease of maintenance. In this article, based on the definition of the terms of maintenance and maintainability, an important tool of Design for Maintenance is developed as a way to improve maintainability through design. A set of standard and organized guidelines is provided and maintainability factors in terms of physical design, logistics support and ergonomics are identified. As a specific application of design review, a methodology so called Vector Projection Method is developed to evaluate the maintainability of the mechanical system. Lastly, an example is discussed

  10. Mechanical Properties of Magnesium-Rare Earth Alloy Systems: A Review

    Directory of Open Access Journals (Sweden)

    Sravya Tekumalla

    2014-12-01

    Full Text Available Magnesium-rare earth based alloys are increasingly being investigated due to the formation of highly stable strengthening phases, activation of additional deformation modes and improvement in mechanical properties. Several investigations have been done to study the effect of rare earths when they are alloyed to pure magnesium and other Mg alloys. In this review, the mechanical properties of the previously investigated different magnesium-rare earth based binary alloys, ternary alloys and other higher alloys with more than three alloying elements are presented.

  11. Atomistic modeling of BN nanofillers for mechanical and thermal properties: a review.

    Science.gov (United States)

    Kumar, Rajesh; Parashar, Avinash

    2016-01-07

    Due to their exceptional mechanical properties, thermal conductivity and a wide band gap (5-6 eV), boron nitride nanotubes and nanosheets have promising applications in the field of engineering and biomedical science. Accurate modeling of failure or fracture in a nanomaterial inherently involves coupling of atomic domains of cracks and voids as well as a deformation mechanism originating from grain boundaries. This review highlights the recent progress made in the atomistic modeling of boron nitride nanofillers. Continuous improvements in computational power have made it possible to study the structural properties of these nanofillers at the atomistic scale.

  12. A review of Green's function methods in computational fluid mechanics: Background, recent developments and future directions

    International Nuclear Information System (INIS)

    Dorning, J.

    1981-01-01

    The research and development over the past eight years on local Green's function methods for the high-accuracy, high-efficiency numerical solution of nuclear engineering problems is reviewed. The basic concepts and key ideas are presented by starting with an expository review of the original fully two-dimensional local Green's function methods developed for neutron diffusion and heat conduction, and continuing through the progressively more complicated and more efficient nodal Green's function methods for neutron diffusion, heat conduction and neutron transport to establish the background for the recent development of Green's function methods in computational fluid mechanics. Some of the impressive numerical results obtained via these classes of methods for nuclear engineering problems are briefly summarized. Finally, speculations are proffered on future directions in which the development of these types of methods in fluid mechanics and other areas might lead. (orig.) [de

  13. Science review: Mechanisms of impaired adrenal function in sepsis and molecular actions of glucocorticoids

    OpenAIRE

    Prigent, Hélène; Maxime, Virginie; Annane, Djillali

    2004-01-01

    This review describes current knowledge on the mechanisms that underlie glucocorticoid insufficiency in sepsis and the molecular action of glucocorticoids. In patients with severe sepsis, numerous factors predispose to glucocorticoid insufficiency, including drugs, coagulation disorders and inflammatory mediators. These factors may compromise the hypothalamic–pituitary axis (i.e. secondary adrenal insufficiency) or the adrenal glands (i.e. primary adrenal failure), or may impair glucocorticoi...

  14. Applied structural and solid mechanics section: 1983 review and 1984 programs

    International Nuclear Information System (INIS)

    Chadha, J.A.

    1984-01-01

    This report reviews briefly the applied research and problem solving work carried out by the Applied Structural and Solid Mechanics Section during 1983. In 1983 there was a strong demand for services in the areas of theroretical and experimental stress analysis, heat transfer analysis, nonlinear analysis, and general structural analyses related to nuclear and thermal power plant, and transmission line components. Development of capabilities in these areas progressed well. Proposed work programs for 1984 are outlined in this report

  15. How Does Paying Attention Improve Sexual Functioning in Women? A Review of Mechanisms.

    Science.gov (United States)

    Arora, Nikita; Brotto, Lori A

    2017-07-01

    Female sexual dysfunction (FSD), consisting of a constellation of distressing sexual symptoms, is highly prevalent worldwide. Given the central role played by psychological factors in the development of FSD, psychologically and in particular mindfulness-based interventions have arisen as potential treatment options for women. Although mindfulness-based interventions have been evaluated in samples of women with gynecologic cancer; a history of sexual abuse; multiple sclerosis; and spinal cord injury; and provoked vestibulodynia, the mechanisms by which mindfulness leads to improvements in sexual functioning are largely unstudied. To summarize the literature on mechanisms of mindfulness interventions in general and to hypothesize which mechanisms most likely apply to samples of women with FSD. Medline was searched with terms such as mindfulness, meditation, mediator, mode, moderator, mechanism, sex, and sexual dysfunction. Only studies that conducted a formal mediation or moderation analysis were included. We also conducted a broader review on mechanisms in other populations, with slightly modified inclusion criteria: the terms sex and sexual dysfunction were removed and only studies from 2012 to 2016 and studies that included an active mindfulness intervention were included. In general populations, trait mindfulness and decentering were the most common mechanisms identified for the efficacy of mindfulness. In four studies that examined mediators of improvement in samples with FSD, the following mediators were found to be significant: relationship satisfaction, genital self-image, interoceptive awareness, depressed mood, anxiety, and trait mindfulness, of which interoceptive awareness had the most supporting evidence. Clinicians and researchers can use the identified mediators of improvement (ie, interoceptive awareness, depression, and trait mindfulness) when making decisions about which patient might be more likely to benefit from a mindfulness-based approach to

  16. Mechanics of the Delayed Fracture of Viscoelastic Bodies with Cracks: Theory and Experiment (Review)

    Science.gov (United States)

    Kaminsky, A. A.

    2014-09-01

    Theoretical and experimental studies on the deformation and delayed fracture of viscoelastic bodies due to slow subcritical crack growth are reviewed. The focus of this review is on studies of subcritical growth of cracks with well-developed fracture process zones, the conditions that lead to their critical development, and all stages of slow crack growth from initiation to the onset of catastrophic growth. Models, criteria, and methods used to study the delayed fracture of viscoelastic bodies with through and internal cracks are analyzed. Experimental studies of the fracture process zones in polymers using physical and mechanical methods as well as theoretical studies of these zones using fracture mesomechanics models that take into account the structural and rheological features of polymers are reviewed. Particular attention is given to crack growth in anisotropic media, the effect of the aging of viscoelastic materials on their delayed fracture, safe external loads that do not cause cracks to propagate, the mechanism of multiple-flaw fracture of viscoelastic bodies with several cracks and, especially, processes causing cracks to coalesce into a main crack, which may result in a break of the body. Methods and results of solving two- and three-dimensional problems of the mechanics of delayed fracture of aging and non-aging viscoelastic bodies with cracks under constant and variable external loads, wedging, and biaxial loads are given

  17. Systematic Reviews of Mechanisms for Financing Family Planning: Findings, Implications, and Future Agenda.

    Science.gov (United States)

    Lissner, Craig L; Ali, Moazzam

    2016-12-01

    The article describes an international collaboration that systematically reviewed the evidence on financing mechanisms for family planning/contraception, assessed the strength of and summarized the evidence, identified research gaps, and proposed a new research agenda to address the gaps. The review found that the evidence base is weak owing to the paucity of studies, diversity in findings, and variations in intervention, study design, and outcome measures. Of more than 17,000 papers reviewed only 38 met the eligibility criteria. A number of general recommendations on the directions and areas of future research can be drawn. There is a strong need for more robust study designs on the effectiveness of financial incentives in family planning. © 2016 The Population Council, Inc.

  18. L-Area STS MTR/NRU/NRX Grapple Assembly Closure Mechanics Review

    International Nuclear Information System (INIS)

    Huizenga, D. J.

    2016-01-01

    A review of the closure mechanics associated with the Shielded Transfer System (STS) MTR/NRU/NRX grapple assembly utilized at the Savannah River Site (SRS) was performed. This review was prompted by an operational event which occurred at the Canadian Nuclear Laboratories (CNL) utilizing a DTS-XL grapple assembly which is essentially identical to the STS MTR/NRU/NRX grapple assembly used at the SRS. The CNL operational event occurred when a NRU/NRX fuel basket containing spent nuclear fuel assemblies was inadvertently released by the DTS-XL grapple assembly during a transfer. The SM review of the STS MTR/NRU/NRX grapple assembly will examine the operational aspects of the STS and the engineered features of the STS which prevent such an event at the SRS. The design requirements for the STS NRU/NRX modifications and the overall layout of the STS are provided in other documents.

  19. Lessons learned in testing of Safeguards equipment

    International Nuclear Information System (INIS)

    Pepper, Susan; Farnitano, Michael; Carelli, Joseph

    2001-01-01

    Full text: During the 1990s, the IAEA Department of Safeguards began a transition from analog to digital equipment. This included surveillance equipment, seals, NDA measurement systems, and other instruments. The transition to digital equipment was intended to facilitate compatibility between and integration of instruments, remote communication of data, improved data storage, and modernization. Many of the instruments are designed to operate on battery power during loss of facility power, and therefore, are designed to consume minimal power. In 2000, the IAEA experienced a number of failures in digital image surveillance (DIS) equipment. A study of the performance data revealed that the failures occurred in 'high risk' environments where the systems were exposed to neutrons. As a supporter of IAEA equipment development and implementation, the U.S. Support Program worked with the IAEA, the equipment designer, and the equipment manufacturer in special meetings on DIS to determine the cause of the failures. It was as a result of these meetings that single event upset (SEU) was determined to be the root cause of the failures. The meeting participants also identified a list of actions to improve the reliability of DIS systems. As a result of the DIS meetings and the identified actions, the U.S. Support Program approved a request from the IAEA and established Task E.125, 'Remote Monitoring and Unattended Digital Surveillance Systems.' This task is an umbrella task intended to provide a mechanism for response to IAEA needs related to improving the reliability of unattended, remote monitoring and DIS equipment. Subtasks approved under this task include: E.125.1, 'SDIS Software Consolidation and DCM-14 Audit' - This subtask involves the consolidation of a number of individual upgrades to the SDIS and review of the DCM-14 software. As the sponsor of the design of the DCM-14 by Dr. Neumann, the German Support Program is also a participant in this subtask; E.125.2, 'DIS

  20. A Review of Low Frequency Electromagnetic Wave Phenomena Related to Tropospheric-Ionospheric Coupling Mechanisms

    Science.gov (United States)

    Simoes, Fernando; Pfaff, Robert; Berthelier, Jean-Jacques; Klenzing, Jeffrey

    2012-01-01

    Investigation of coupling mechanisms between the troposphere and the ionosphere requires a multidisciplinary approach involving several branches of atmospheric sciences, from meteorology, atmospheric chemistry, and fulminology to aeronomy, plasma physics, and space weather. In this work, we review low frequency electromagnetic wave propagation in the Earth-ionosphere cavity from a troposphere-ionosphere coupling perspective. We discuss electromagnetic wave generation, propagation, and resonance phenomena, considering atmospheric, ionospheric and magnetospheric sources, from lightning and transient luminous events at low altitude to Alfven waves and particle precipitation related to solar and magnetospheric processes. We review in situ ionospheric processes as well as surface and space weather phenomena that drive troposphere-ionosphere dynamics. Effects of aerosols, water vapor distribution, thermodynamic parameters, and cloud charge separation and electrification processes on atmospheric electricity and electromagnetic waves are reviewed. We also briefly revisit ionospheric irregularities such as spread-F and explosive spread-F, sporadic-E, traveling ionospheric disturbances, Trimpi effect, and hiss and plasma turbulence. Regarding the role of the lower boundary of the cavity, we review transient surface phenomena, including seismic activity, earthquakes, volcanic processes and dust electrification. The role of surface and atmospheric gravity waves in ionospheric dynamics is also briefly addressed. We summarize analytical and numerical tools and techniques to model low frequency electromagnetic wave propagation and solving inverse problems and summarize in a final section a few challenging subjects that are important for a better understanding of tropospheric-ionospheric coupling mechanisms.

  1. Protective equipment use among female rugby players.

    Science.gov (United States)

    Comstock, R Dawn; Fields, Sarah K; Knox, Christy L

    2005-07-01

    Our objective was to assess the prevalence of protective equipment use and the motivation for using protective equipment among a sample of US female rugby players. We surveyed a convenience sample of 234 current US female rugby players from 14 teams participating in a US women's rugby tournament, obtaining self-reported demographic, rugby exposure, and protective equipment use information. Mouthguards were the most commonly used piece of protective equipment: 90.8% of players reported having always worn a mouthguard while playing or practicing rugby within their most recent 3 months of play. Fewer than 15% of players reported having always worn other types of protective equipment. Equipment use varied by playing position. Whereas over 80% of players in all other positions always wore a mouthguard, 66.7% of scrum halves reported always wearing one. Both backs and forwards reported wearing shoulder pads, but only forwards reported always wearing padded headgear. Mouthguards, padded headgear, and shoulder pads were worn "to prevent injury," whereas ankle braces, neoprene sleeves, and athletic tape on joints were worn "to protect a current/recent injury." This is the first study of female rugby players to assess the prevalence of protective equipment use by playing position and the motivation for using protective equipment. With the exception of mouthguards, US female rugby players infrequently use protective equipment. Protective equipment use varies by playing position. Some types of protective equipment appear to be used as primary prevention mechanisms, whereas others are used as secondary or tertiary prevention mechanisms.

  2. Effect of process parameters on microstructure and mechanical properties of friction stir welded joints: A review

    Science.gov (United States)

    Wanare, S. P.; Kalyankar, V. D.

    2018-04-01

    Friction stir welding is emerging as a promising technique for joining of lighter metal alloys due to its several advantages over conventional fusion welding processes such as low thermal distortion, good mechanical properties, fine weld joint microstructure, etc. This review article mainly focuses on analysis of microstructure and mechanical properties of friction stir welded joints. Various microstructure characterization techniques used by previous researchers such as optical microscopes, x-ray diffraction, electron probe microscope, transmission electron microscope, scanning electron microscopes with electron back scattered diffraction, electron dispersive microscopy, etc. are thoroughly overviewed and their results are discussed. The effects of friction stir welding process parameters such as tool rotational speed, welding speed, tool plunge depth, axial force, tool shoulder diameter to tool pin diameter ratio, tool geometry etc. on microstructure and mechanical properties of welded joints are studied and critical observations are noted down. The microstructure examination carried out by previous researchers on various zones of welded joints such as weld zone, heat affected zone and base metal are studied and critical remarks have been presented. Mechanical performances of friction stir welded joints based on tensile test, micro-hardness test, etc. are discussed. This article includes exhaustive literature review of standard research articles which may become ready information for subsequent researchers to establish their line of action.

  3. Silver (Ag) Transport Mechanisms in TRISO coated particles: A Critical Review

    Energy Technology Data Exchange (ETDEWEB)

    I J van Rooyen; J H Neethling; J A A Engelbrecht; P M van Rooyen; G Strydom

    2012-10-01

    Transport of 110mAg in the intact SiC layer of TRISO coated particles has been studied for approximately 30 years without arriving at a satisfactory explanation of the transport mechanism. In this paper the possible mechanisms postulated in previous experimental studies, both in-reactor and out-of reactor research environment studies are critically reviewed and of particular interest are relevance to very high temperature gas reactor operating and accident conditions. Among the factors thought to influence Ag transport are grain boundary stoichiometry, SiC grain size and shape, the presence of free silicon, nano-cracks, thermal decomposition, palladium attack, transmutation products, layer thinning and coated particle shape. Additionally new insight to nature and location of fission products has been gained via recent post irradiation electron microscopy examination of TRISO coated particles from the DOE’s fuel development program. The combined effect of critical review and new analyses indicates a direction for investigating possible the Ag transport mechanism including the confidence level with which these mechanisms may be experimentally verified.

  4. Mechanisms of action of fungi and bacteria used as biofertilizers in agricultural soils : a systematic review

    Directory of Open Access Journals (Sweden)

    Sara Paulina Restrepo-Correa

    2017-05-01

    Full Text Available Phosphorus, nitrogen, iron and potassium are some compounds necessary for plant growth and development; chemical fertilizers used to increase concentration significantly affect the environment and soil ecosystems. According to the scientific literature, microorganisms with biofertilizer potential have demonstrated various mechanisms of action to solubilize these compounds and thus meet the requirements of plants. This systematic review collects scientific information that describes the mechanisms of action of microbial fertilizers in agricultural soils, published between 2004 and 2014, in three different databases; ScienceDirect, SpringerLink and Scopus,using the search path (biofertilizer AND (bacteria OR fungi AND (effect OR action OR mechanism. After using different inclusion and exclusion criteria, the search displayed a total of 63 original articles, including six unindexed documents. As a result of the systematic review, it indicates that the production of various organic acids allows soil acidification, facilitating absorption of elements. It was also observed that solubilization of P is the most described mechanism, by obtaining a solubilizing of 726.5 mg/L of P due to P. pseudoalcaligenes

  5. Silver (Ag) transport mechanisms in TRISO coated particles: A critical review

    Energy Technology Data Exchange (ETDEWEB)

    Rooyen, I.J. van, E-mail: isabella.vanrooyen@inl.gov [Idaho National Laboratory, Idaho Falls, ID 83415-6188 (United States); Dunzik-Gougar, M.L. [Department of Nuclear Engineering, Idaho State University, ID (United States); Rooyen, P.M. van [Philip M. van Rooyen Network Consultants, Midlands Estates (South Africa)

    2014-05-01

    Transport of {sup 110m}Ag in the intact SiC layer of TRISO coated particles has been studied for approximately 30 years without arriving at a satisfactory explanation of the transport mechanism. In this paper the possible mechanisms postulated in previous experimental studies, both in-reactor and out-of reactor research environment studies are critically reviewed and of particular interest are relevance to very high temperature gas reactor operating and accident conditions. Among the factors thought to influence Ag transport are grain boundary stoichiometry, SiC grain size and shape, the presence of free silicon, nano-cracks, thermal decomposition, palladium attack, transmutation products, layer thinning and coated particle shape. Additionally new insight to nature and location of fission products has been gained via recent post irradiation electron microscopy examination of TRISO coated particles from the DOE's fuel development program. The combined effect of critical review and new analyses indicates a direction for investigating possible the Ag transport mechanism including the confidence level with which these mechanisms may be experimentally verified.

  6. Mechanisms of Acupuncture Therapy in Ischemic Stroke Rehabilitation: A Literature Review of Basic Studies.

    Science.gov (United States)

    Chavez, Lina M; Huang, Shiang-Suo; MacDonald, Iona; Lin, Jaung-Geng; Lee, Yu-Chen; Chen, Yi-Hung

    2017-10-28

    Acupuncture is recommended by the World Health Organization (WHO) as an alternative and complementary strategy for stroke treatment and for improving stroke care. Clinical trial and meta-analysis findings have demonstrated the efficacy of acupuncture in improving balance function, reducing spasticity, and increasing muscle strength and general well-being post-stroke. The mechanisms underlying the beneficial effects of acupuncture in stroke rehabilitation remain unclear. The aim of this study was to conduct a literature review, summarize the current known mechanisms in ischemic stroke rehabilitation through acupuncture and electroacupuncture (EA) therapy, and to detail the frequently used acupoints implicated in these effects. The evidence in this review indicates that five major different mechanisms are involved in the beneficial effects of acupuncture/EA on ischemic stroke rehabilitation: (1) Promotion of neurogenesis and cell proliferation in the central nervous system (CNS); (2) Regulation of cerebral blood flow in the ischemic area; (3) Anti-apoptosis in the ischemic area; (4) Regulation of neurochemicals; and, (5) Improvement of impaired long-term potentiation (LTP) and memory after stroke. The most frequently used acupoints in basic studies include Baihui (GV20), Zusanli (ST36), Quchi (LI11), Shuigou (GV26), Dazhui (GV14), and Hegu (LI4). Our findings show that acupuncture exerts a beneficial effect on ischemic stroke through modulation of different mechanisms originating in the CNS.

  7. Advances in classical and analytical mechanics: A reviews of author’s results

    Directory of Open Access Journals (Sweden)

    Hedrih-Stevanović Katica R.

    2013-01-01

    Full Text Available A review, in subjective choice, of author’s scientific results in area of: classical mechanics, analytical mechanics of discrete hereditary systems, analytical mechanics of discrete fractional order system vibrations, elastodynamics, nonlinear dynamics and hybrid system dynamics is presented. Main original author’s results were presented through the mathematical methods of mechanics with examples of applications for solving problems of mechanical real system dynamics abstracted to the theoretical models of mechanical discrete or continuum systems, as well as hybrid systems. Paper, also, presents serries of methods and scientific results authored by professors Mitropolyski, Andjelić and Rašković, as well as author’s of this paper original scientific research results obtained by methods of her professors. Vector method based on mass inertia moment vectors and corresponding deviational vector components for pole and oriented axis, defined in 1991 by K. Hedrih, is presented. Results in construction of analytical dynamics of hereditary discrete system obtained in collaboration with O. A. Gorosho are presented. Also, some selections of results author’s postgraduate students and doctorantes in area of nonlinear dynamics are presented. A list of scientific projects headed by author of this paper is presented with a list of doctoral dissertation and magister of sciences thesis which contain scientific research results obtained under the supervision by author of this paper or their fist doctoral candidates. [Projekat Ministarstva nauke Republike Srbije, br. ON174001: Dynamics of hybrid systems with complex structures

  8. Review on Molecular Mechanisms of Antifouling Compounds: An Update since 2012.

    Science.gov (United States)

    Chen, Lianguo; Qian, Pei-Yuan

    2017-08-28

    Better understanding of the mechanisms of antifouling compounds is recognized to be of high value in establishing sensitive biomarkers, allowing the targeted optimization of antifouling compounds and guaranteeing environmental safety. Despite vigorous efforts to find new antifouling compounds, information about the mechanisms of antifouling is still scarce. This review summarizes the progress into understanding the molecular mechanisms underlying antifouling activity since 2012. Non-toxic mechanisms aimed at specific targets, including inhibitors of transmembrane transport, quorum sensing inhibitors, neurotransmission blockers, adhesive production/release inhibitors and enzyme/protein inhibitors, are put forward for natural antifouling products or shelf-stable chemicals. Several molecular targets show good potential for use as biomarkers in future mechanistic screening, such as acetylcholine esterase for neurotransmission, phenoloxidase/tyrosinase for the formation of adhesive plaques, N -acyl homoserine lactone for quorum sensing and intracellular Ca 2+ levels as second messenger. The studies on overall responses to challenges by antifoulants can be categorized as general targets, including protein expression/metabolic activity regulators, oxidative stress inducers, neurotransmission blockers, surface modifiers, biofilm inhibitors, adhesive production/release inhibitors and toxic killing. Given the current situation and the knowledge gaps regarding the development of alternative antifoulants, a basic workflow is proposed that covers the indispensable steps, including preliminary mechanism- or bioassay-guided screening, evaluation of environmental risks, field antifouling performance, clarification of antifouling mechanisms and the establishment of sensitive biomarkers, which are combined to construct a positive feedback loop.

  9. Mechanical characteristics of hardened concrete with different mineral admixtures: a review.

    Science.gov (United States)

    Ayub, Tehmina; Khan, Sadaqat Ullah; Memon, Fareed Ahmed

    2014-01-01

    The available literature identifies that the addition of mineral admixture as partial replacement of cement improves the microstructure of the concrete (i.e., porosity and pore size distribution) as well as increasing the mechanical characteristics such as drying shrinkage and creep, compressive strength, tensile strength, flexural strength, and modulus of elasticity; however, no single document is available in which review and comparison of the influence of the addition of these mineral admixtures on the mechanical characteristics of the hardened pozzolanic concretes are presented. In this paper, based on the reported results in the literature, mechanical characteristics of hardened concrete partially containing mineral admixtures including fly ash (FA), silica fume (SF), ground granulated blast furnace slag (GGBS), metakaolin (MK), and rice husk ash (RHA) are discussed and it is concluded that the content and particle size of mineral admixture are the parameters which significantly influence the mechanical properties of concrete. All mineral admixtures enhance the mechanical properties of concrete except FA and GGBS which do not show a significant effect on the strength of concrete at 28 days; however, gain in strength at later ages is considerable. Moreover, the comparison of the mechanical characteristics of different pozzolanic concretes suggests that RHA and SF are competitive.

  10. A critical review of the arsenic uptake mechanisms and phytoremediation potential of Pteris vittata.

    Science.gov (United States)

    Danh, Luu Thai; Truong, Paul; Mammucari, Raffaella; Foster, Neil

    2014-01-01

    The discovery of the arsenic hyperaccumulator, Pteris vittata (Chinese brake fern), has contributed to the promotion of its application as a means of phytoremediation for arsenic removal from contaminated soils and water. Understanding the mechanisms involved in arsenic tolerance and accumulation of this plant provides valuable tools to improve the phytoremediation efficiency. In this review, the current knowledge about the physiological and molecular mechanisms of arsenic tolerance and accumulation in P. vittata is summarized, and an attempt has been made to clarify some of the unresolved questions related to these mechanisms. In addition, the capacity of P. vittata for remediation of arsenic-contaminated soils is evaluated under field conditions for the first time, and possible solutions to improve the remediation capacity of Pteris vittata are also discussed.

  11. Biophysical Stimuli: A Review of Electrical and Mechanical Stimulation in Hyaline Cartilage.

    Science.gov (United States)

    Vaca-González, Juan J; Guevara, Johana M; Moncayo, Miguel A; Castro-Abril, Hector; Hata, Yoshie; Garzón-Alvarado, Diego A

    2017-09-01

    Objective Hyaline cartilage degenerative pathologies induce morphologic and biomechanical changes resulting in cartilage tissue damage. In pursuit of therapeutic options, electrical and mechanical stimulation have been proposed for improving tissue engineering approaches for cartilage repair. The purpose of this review was to highlight the effect of electrical stimulation and mechanical stimuli in chondrocyte behavior. Design Different information sources and the MEDLINE database were systematically revised to summarize the different contributions for the past 40 years. Results It has been shown that electric stimulation may increase cell proliferation and stimulate the synthesis of molecules associated with the extracellular matrix of the articular cartilage, such as collagen type II, aggrecan and glycosaminoglycans, while mechanical loads trigger anabolic and catabolic responses in chondrocytes. Conclusion The biophysical stimuli can increase cell proliferation and stimulate molecules associated with hyaline cartilage extracellular matrix maintenance.

  12. Mechanical Stimulation Protocols of Human Derived Cells in Articular Cartilage Tissue Engineering - A Systematic Review.

    Science.gov (United States)

    Khozoee, Baktash; Mafi, Pouya; Mafi, Reza; Khan, Wasim S

    2017-01-01

    Mechanical stimulation is a key factor in articular cartilage generation and maintenance. Bioreactor systems have been designed and built in order to deliver specific types of mechanical stimulation. The focus has been twofold, applying a type of preconditioning in order to stimulate cell differentiation, and to simulate in vivo conditions in order to gain further insight into how cells respond to different stimulatory patterns. Due to the complex forces at work within joints, it is difficult to simulate mechanical conditions using a bioreactor. The aim of this review is to gain a deeper understanding of the complexities of mechanical stimulation protocols by comparing those employed in bioreactors in the context of tissue engineering for articular cartilage, and to consider their effects on cultured cells. Allied and Complementary Medicine 1985 to 2016, Ovid MEDLINE[R] 1946 to 2016, and Embase 1974 to 2016 were searched using key terms. Results were subject to inclusion and exclusion criteria, key findings summarised into a table and subsequently discussed. Based on this review it is overwhelmingly clear that mechanical stimulation leads to increased chondrogenic properties in the context of bioreactor articular cartilage tissue engineering using human cells. However, given the variability and lack of controlled factors between research articles, results are difficult to compare, and a standardised method of evaluating stimulation protocols proved challenging. With improved standardisation in mechanical stimulation protocol reporting, bioreactor design and building processes, along with a better understanding of joint behaviours, we hope to perform a meta-analysis on stimulation protocols and methods. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  13. Equipment Replacement Decision Making: Opportunities and Challenges

    OpenAIRE

    Fan, Wei (David); Gemar, Mason D.; Machemehl, Randy

    2012-01-01

    The primary function of equipment managers is to replace the right equipment at the right time and at the lowest overall cost. In this paper, the opportunities and challenges associated with equipment replacement optimization (ERO) are discussed in detail. First, a comprehensive review of the state-of-the art and state-of-the practice literature for the ERO problem is conducted. Second, a dynamic programming (DP) based optimization solution methodology is presented to solve the ERO problem. T...

  14. Interim guidance on the Standard Review Plan for the review of financial assurance mechanisms for decommissioning under 10 CFR Parts 30, 40, and 70

    International Nuclear Information System (INIS)

    1988-12-01

    Interim Guidance on the Standard Review Plan (SRP) for the Review of Financial Assurance Mechanisms for Decommissioning under 10 CFR Parts 30, 40, and 70 is prepared for the guidance of Nuclear Regulatory Commission staff reviewers in performing reviews of applications from material licensees affected by the decommissioning regulations established June 27, 1988 (53FR24018). The principal purpose of the SRP is to assure the quality and uniformity of staff reviews and to present a base from which to evaluate the financial assurance aspects of the applications. NUREG-1337, identifies who performs the review, the matters that are reviewed, the basis of the review, how the review is performed, and the conclusions that are sought. 3 refs

  15. Efficacy of homecare regimens for mechanical plaque removal in managing gingivitis a meta review.

    Science.gov (United States)

    Van der Weijden, Fridus A; Slot, Dagmar E

    2015-04-01

    Based on evidence as presented in systematic reviews what is the efficacy and safety of available homecare toothbrush regimens for mechanical plaque removal on plaque and gingivitis in adults? Three Internet sources were used (up to and including August 2014) to search for appropriate papers that satisfied the study purpose. Plaque scores and gingivitis scores were considered to be the primary parameter of interest. Safety was considered an important facet in relation to efficacy. Data and conclusions as presented in the selected papers were extracted. The potential risk of bias was estimated and the emerging evidence was graded. Independent screening of 176 unique reviews resulted in 10 published and eligible systematic reviews. They were categorized into one review evaluating the effect of an oral hygiene instruction with a toothbrush on plaque and gingivitis scores, five evaluating the efficacy of manual and power toothbrushes and three reviews evaluating toothbrush safety and one evaluating toothbrush contamination. Tooth brushing is effective in reducing levels of dental plaque. With respect to gingivitis power toothbrushes have a benefit over manual toothbrushes. The greatest body of evidence was available for oscillating-rotating brushes. Tooth brushing generally can be considered safe for the teeth and their investing tissues. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  16. Mechanical properties of provisional dental materials: A systematic review and meta-analysis.

    Science.gov (United States)

    Astudillo-Rubio, Daniela; Delgado-Gaete, Andrés; Bellot-Arcís, Carlos; Montiel-Company, José María; Pascual-Moscardó, Agustín; Almerich-Silla, José Manuel

    2018-01-01

    Provisional restorations represent an important phase during the rehabilitation process, knowledge of the mechanical properties of the available materials allows us to predict their clinical performance. At present, there is no systematic review, which supports the clinicians' criteria, in the selection of a specific material over another for a particular clinical situation. The purpose of this systematic review and meta-analysis was to assess and compare the mechanical properties of dimethacrylates and monomethacrylates used in fabricating direct provisional restorations, in terms of flexural strength, fracture toughness and hardness. This review followed the PRISMA guidelines. The searches were conducted in PubMed, Embase, Web of Science, Scopus, the New York Academy of Medicine Grey Literature Report and were complemented by hand-searching, with no limitation of time or language up to January 10, 2017. Studies that assess and compare the mechanical properties of dimethacrylate- and monomethacrylate-based provisional restoration materials were selected. A quality assessment of full-text articles were performed according to modified ARRIVE and CONSORT criteria and modified Cochrane Collaboration's tool for in vitro studies. Initially, 256 articles were identified. After removing the duplicates and applying the selection criteria, 24 articles were included in the qualitative synthesis and 7 were included in the quantitative synthesis (meta-analysis). It may be concluded that dimethacrylate-based provisional restorations presented better mechanical behavior than monomethacrylate-based ones in terms of flexural strength and hardness. Fracture toughness showed no significant differences. Within the monomethacrylate group, polymethylmethacrylate showed greater flexural strength than polyethylmethacrylate.

  17. Mechanical properties of provisional dental materials: A systematic review and meta-analysis.

    Directory of Open Access Journals (Sweden)

    Daniela Astudillo-Rubio

    Full Text Available Provisional restorations represent an important phase during the rehabilitation process, knowledge of the mechanical properties of the available materials allows us to predict their clinical performance. At present, there is no systematic review, which supports the clinicians' criteria, in the selection of a specific material over another for a particular clinical situation. The purpose of this systematic review and meta-analysis was to assess and compare the mechanical properties of dimethacrylates and monomethacrylates used in fabricating direct provisional restorations, in terms of flexural strength, fracture toughness and hardness. This review followed the PRISMA guidelines. The searches were conducted in PubMed, Embase, Web of Science, Scopus, the New York Academy of Medicine Grey Literature Report and were complemented by hand-searching, with no limitation of time or language up to January 10, 2017. Studies that assess and compare the mechanical properties of dimethacrylate- and monomethacrylate-based provisional restoration materials were selected. A quality assessment of full-text articles were performed according to modified ARRIVE and CONSORT criteria and modified Cochrane Collaboration's tool for in vitro studies. Initially, 256 articles were identified. After removing the duplicates and applying the selection criteria, 24 articles were included in the qualitative synthesis and 7 were included in the quantitative synthesis (meta-analysis. It may be concluded that dimethacrylate-based provisional restorations presented better mechanical behavior than monomethacrylate-based ones in terms of flexural strength and hardness. Fracture toughness showed no significant differences. Within the monomethacrylate group, polymethylmethacrylate showed greater flexural strength than polyethylmethacrylate.

  18. 30 CFR 77.410 - Mobile equipment; automatic warning devices.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Mobile equipment; automatic warning devices. 77... UNDERGROUND COAL MINES Safeguards for Mechanical Equipment § 77.410 Mobile equipment; automatic warning devices. (a) Mobile equipment such as front-end loaders, forklifts, tractors, graders, and trucks, except...

  19. The Antihyperglycemic Effects of Rhizoma Coptidis and Mechanism of Actions: A Review of Systematic Reviews and Pharmacological Research

    Directory of Open Access Journals (Sweden)

    Hui Wang

    2014-01-01

    Full Text Available Rhizoma Coptidis (Huang Lian in Chinese pinyin is among the most widely used traditional Chinese herbal medicines and has a profound history of more than 2000 years of being used as a therapeutic herb. The antidiabetic effects of Rhizoma Coptidis have been extensively investigated in animal experiments and clinical trials and its efficacy as a promising antihyperglycemic agent has been widely discussed. In the meantime, findings from modern pharmacological studies have contributed the majority of its bioactivities to berberine, the isoquinoline alkaloids component of the herb, and a number of experiments testing the antidiabetic effects of berberine have been initiated. Therefore, we conducted a review of the current evidence profile of the antihyperglycemic effects of Rhizoma Coptidis as well as its main component berberine and the possible mechanism of actions, in order to summarize research evidence in this area and identify future research directions.

  20. A Comparison of Over-the-Counter Mechanical Nasal Dilators: A Systematic Review.

    Science.gov (United States)

    Kiyohara, Nicole; Badger, Christopher; Tjoa, Tjoson; Wong, Brian

    2016-09-01

    The internal nasal valve is the narrowest part of the nasal airway and a common site of inspiratory collapse and obstruction of nasal airflow. Over-the-counter mechanical nasal dilators are an alternative to surgical intervention that attempts to improve airflow through the internal nasal valve. To determine the efficacy of over-the-counter mechanical nasal dilators and classify these products by mechanism. A database of 33 available over-the-counter mechanical nasal dilators was generated via a PubMed search as well as an internet search via Amazon.com and Google, conducted from April 1, 2013, through December 31, 2015. Products determined to be unavailable or discontinued were excluded from the database. Of the devices examined in published literature, efficacy was based on objective measures, such as measured airflow, the cross-sectional area of the nasal valve, and changes in resistance. Measures of reported sleep quality or patient perception were excluded. An analysis of each product's mechanism revealed 4 broad classes: external nasal dilator strips, nasal stents, nasal clips, and septal stimulators. A review demonstrated 5 studies supporting the use of external nasal dilator strips, 4 studies supporting the use of nasal clips, 1 study supporting the use of nasal stents, and no studies supporting the use of septal stimulators. Our findings suggest that external nasal dilator strips and nasal clips effectively relieve obstruction of the internal nasal valve and may be an alternative to surgical intervention in some patients.

  1. Various bio-mechanical factors affecting heat generation during osteotomy preparation: A systematic review.

    Science.gov (United States)

    Chauhan, Chirag J; Shah, Darshana N; Sutaria, Foram B

    2018-01-01

    As implant site preparation and bone are critical precursors to primary healing, thermal and mechanical damage to the bone must be minimized during the preparation of the implant site. Moreover, excessively traumatic surgery can adversely affect the maturation of bone tissue at the bone/implant interface and consequently diminish the predictability of osseointegration. So, this study was carried out to evaluate the various biological and mechanical factors responsible for heat generation during osteotomy site preparation to reduce the same for successful osseointegration of dental implants. A broad search of the dental literature in PubMed added by manual search was performed for articles published between 1992 and December 2015. Various bio-mechanical factors related to dental implant osteotomy preparation such as dental implant drill designs/material/wear, drilling methods, type of irrigation, and bone quality were reviewed. Titles and abstracts were screened and articles which fulfilled the inclusion criteria were selected for a full-text reading. The initial database search yielded 123 titles, of which 59 titles were discarded after reading the titles and abstracts, 30 articles were again excluded based on inclusion and exclusion criteria, and finally 34 articles were selected for data extraction. Many biological and mechanical factors responsible for heat generation were found. Literatures of this review study have indicated that there are various bio-mechanical reasons, which affect the temperature rise during osteotomy and suggest that the amount of heat generation is a multifactorial in nature and it should be minimized for better primary healing of the implant site.

  2. Mechanical behaviour of degradable phosphate glass fibres and composites-a review.

    Science.gov (United States)

    Colquhoun, R; Tanner, K E

    2015-12-23

    Biodegradable materials are potentially an advantageous alternative to the traditional metallic fracture fixation devices used in the reconstruction of bone tissue defects. This is due to the occurrence of stress shielding in the surrounding bone tissue that arises from the absence of mechanical stimulus to the regenerating bone due to the mismatch between the elastic modulus of bone and the metal implant. However although degradable polymers may alleviate such issues, these inert materials possess insufficient mechanical properties to be considered as a suitable alternative to current metallic devices at sites of sufficient mechanical loading. Phosphate based glasses are an advantageous group of materials for tissue regenerative applications due to their ability to completely degrade in vivo at highly controllable rates based on the specific glass composition. Furthermore the release of the glass's constituent ions can evoke a therapeutic stimulus in vivo (i.e. osteoinduction) whilst also generating a bioactive response. The processing of these materials into fibres subsequently allows them to act as reinforcing agents in degradable polymers to simultaneously increase its mechanical properties and enhance its in vivo response. However despite the various review articles relating to the compositional influences of different phosphate glass systems, there has been limited work summarising the mechanical properties of different phosphate based glass fibres and their subsequent incorporation as a reinforcing agent in degradable composite materials. As a result, this review article examines the compositional influences behind the development of different phosphate based glass fibre compositions intended as composite reinforcing agents along with an analysis of different potential composite configurations. This includes variations in the fibre content, matrix material and fibre architecture as well as other novel composites designs.

  3. Shipboard and laboratory equipment

    Digital Repository Service at National Institute of Oceanography (India)

    Shyamprasad, M.; Ramaswamy, V.

    The polymetallic nodules occur at an average depth of 4500 m. Adequate equipment and techniques are required for the exploration at such depths. Shipboard and various laboratory equipments for the sampling of polymetallic nodules is described...

  4. Remote handling equipment

    International Nuclear Information System (INIS)

    Clement, G.

    1984-01-01

    After a definition of intervention, problems encountered for working in an adverse environment are briefly analyzed for development of various remote handling equipments. Some examples of existing equipments are given [fr

  5. Clinical Efficacy of Acupuncture on Rheumatoid Arthritis and Associated Mechanisms: A Systemic Review

    Directory of Open Access Journals (Sweden)

    Pei-Chi Chou

    2018-01-01

    Full Text Available Objective. The objective of this review is to investigate the detailed existing scientific information about the clinical efficacy of acupuncture on rheumatoid arthritis (RA conditions and to reveal the proposed mechanisms. Methods. We searched the PubMed, EMBASE, Cochrane, AMED (Allied and Complementary Medicine, NCCAM (The National Center for Complementary and Alternative Medicine, and CNKI (China National Knowledge Infrastructure databases to identify relevant monographs and related references from 1974 to 2018. Chinese journals and theses/dissertations were hand searched. Results. 43 studies were recruited. Each research was analyzed for study design, subject characteristics, intervention, selected acupoints, assessment parameters, proposed mechanisms, and results/conclusions. Conclusions. In our review, we concluded that acupuncture alone or combined with other treatment modalities is beneficial to the clinical conditions of RA without adverse effects reported and can improve function and quality of life and is worth trying. Several important possible mechanisms were summarized including anti-inflammatory effect, antioxidative effect, and regulation of immune system function. However, there is still inconsistency regarding the clinical efficacy and lack of well-designed human/animal double-blinded RCTs. Future discussion for further agreement on taking traditional Chinese medicine (TCM theory into consideration as much as possible is a top priority.

  6. Quantum mechanics of excitation transport in photosynthetic complexes: a key issues review.

    Science.gov (United States)

    Levi, Federico; Mostarda, Stefano; Rao, Francesco; Mintert, Florian

    2015-07-01

    For a long time microscopic physical descriptions of biological processes have been based on quantum mechanical concepts and tools, and routinely employed by chemical physicists and quantum chemists. However, the last ten years have witnessed new developments on these studies from a different perspective, rooted in the framework of quantum information theory. The process that more, than others, has been subject of intense research is the transfer of excitation energy in photosynthetic light-harvesting complexes, a consequence of the unexpected experimental discovery of oscillating signals in such highly noisy systems. The fundamental interdisciplinary nature of this research makes it extremely fascinating, but can also constitute an obstacle to its advance. Here in this review our objective is to provide an essential summary of the progress made in the theoretical description of excitation energy dynamics in photosynthetic systems from a quantum mechanical perspective, with the goal of unifying the language employed by the different communities. This is initially realized through a stepwise presentation of the fundamental building blocks used to model excitation transfer, including protein dynamics and the theory of open quantum system. Afterwards, we shall review how these models have evolved as a consequence of experimental discoveries; this will lead us to present the numerical techniques that have been introduced to quantitatively describe photo-absorbed energy dynamics. Finally, we shall discuss which mechanisms have been proposed to explain the unusual coherent nature of excitation transport and what insights have been gathered so far on the potential functional role of such quantum features.

  7. A review of toxicity and mechanisms of individual and mixtures of heavy metals in the environment.

    Science.gov (United States)

    Wu, Xiangyang; Cobbina, Samuel J; Mao, Guanghua; Xu, Hai; Zhang, Zhen; Yang, Liuqing

    2016-05-01

    The rational for the study was to review the literature on the toxicity and corresponding mechanisms associated with lead (Pb), mercury (Hg), cadmium (Cd), and arsenic (As), individually and as mixtures, in the environment. Heavy metals are ubiquitous and generally persist in the environment, enabling them to biomagnify in the food chain. Living systems most often interact with a cocktail of heavy metals in the environment. Heavy metal exposure to biological systems may lead to oxidation stress which may induce DNA damage, protein modification, lipid peroxidation, and others. In this review, the major mechanism associated with toxicities of individual metals was the generation of reactive oxygen species (ROS). Additionally, toxicities were expressed through depletion of glutathione and bonding to sulfhydryl groups of proteins. Interestingly, a metal like Pb becomes toxic to organisms through the depletion of antioxidants while Cd indirectly generates ROS by its ability to replace iron and copper. ROS generated through exposure to arsenic were associated with many modes of action, and heavy metal mixtures were found to have varied effects on organisms. Many models based on concentration addition (CA) and independent action (IA) have been introduced to help predict toxicities and mechanisms associated with metal mixtures. An integrated model which combines CA and IA was further proposed for evaluating toxicities of non-interactive mixtures. In cases where there are molecular interactions, the toxicogenomic approach was used to predict toxicities. The high-throughput toxicogenomics combines studies in genetics, genome-scale expression, cell and tissue expression, metabolite profiling, and bioinformatics.

  8. Fracture mechanics of thin wall cylindrical pressure vessels: an interim review

    International Nuclear Information System (INIS)

    Kurtz, R.J.; Olson, N.J.

    1977-08-01

    The report is a result of activities in the LMFBR Fuel Rod Transient Performance Program sponsored by the LMFBR Branch of the Division of Project Management, U.S. Nuclear Regulatory Commission. One of the objectives is to develop predictions relative to the length, direction, and rate of growth of cladding rips subsequent to (or concurrent with) the initial cladding breach during unprotected transients. To provide a basis for evaluation, Battelle, Pacific Northwest Laboratories has reviewed most available fracture mechanics assessments relative to thin-wall cylindrical pressure vessels. The purpose of the report is to review the various fracture mechanics models and to describe the pertinent fracture parameters. It is intended to provide a formal basis for assessing future analytical predictions of fracture behavior of materials exposed to transient LMFBR thermal and mechanical loading conditions. In addition, the report is expected to provide reference material for evaluating or developing experimental programs required to properly address the problem of predicting fracture behavior of materials during transient events

  9. Fe–Al–Mn–C lightweight structural alloys: a review on the microstructures and mechanical properties

    Directory of Open Access Journals (Sweden)

    Hansoo Kim, Dong-Woo Suh and Nack J Kim

    2013-01-01

    Full Text Available Adding a large amount of light elements such as aluminum to steels is not a new concept recalling that several Fe–Al–Mn–C alloys were patented in 1950s for replacement of nickel or chromium in corrosion resistance steels. However, the so-called lightweight steels or low-density steels were revisited recently, which is driven by demands from the industry where steel has served as a major structural material. Strengthening without loss of ductility has been a triumph in steel research, but lowering the density of steel by mixing with light elements will be another prospect that may support the competitiveness against emerging alternatives such as magnesium alloys. In this paper, we review recent studies on lightweight steels, emphasizing the concept of alloy design for microstructures and mechanical properties. The influence of alloying elements on the phase constituents, mechanical properties and the change of density is critically reviewed. Deformation mechanisms of various lightweight steels are discussed as well. This paper provides a reason why the success of lightweight steels is strongly dependent on scientific achievements even though alloy development is closely related to industrial applications. Finally, we summarize some of the main directions for future investigations necessary for vitalizing this field of interest.

  10. Mechanisms and biomaterials in pH-responsive tumour targeted drug delivery: A review.

    Science.gov (United States)

    Kanamala, Manju; Wilson, William R; Yang, Mimi; Palmer, Brian D; Wu, Zimei

    2016-04-01

    As the mainstay in the treatment of various cancers, chemotherapy plays a vital role, but still faces many challenges, such as poor tumour selectivity and multidrug resistance (MDR). Targeted drug delivery using nanotechnology has provided a new strategy for addressing the limitations of the conventional chemotherapy. In the last decade, the volume of research published in this area has increased tremendously, especially with functional nano drug delivery systems (nanocarriers). Coupling a specific stimuli-triggered drug release mechanism with these delivery systems is one of the most prevalent approaches for improving therapeutic outcomes. Among the various stimuli, pH triggered delivery is regarded as the most general strategy, targeting the acidic extracellular microenvironment and intracellular organelles of solid tumours. In this review, we discuss recent advances in the development of pH-sensitive nanocarriers for tumour-targeted drug delivery. The review focuses on the chemical design of pH-sensitive biomaterials, which are used to fabricate nanocarriers for extracellular and/or intracellular tumour site-specific drug release. The pH-responsive biomaterials bring forth conformational changes in these nanocarriers through various mechanisms such as protonation, charge reversal or cleavage of a chemical bond, facilitating tumour specific cell uptake or drug release. A greater understanding of these mechanisms will help to design more efficient drug delivery systems to address the challenges encountered in conventional chemotherapy. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Review on Synthesis, Thermo-Physical Property, and Heat Transfer Mechanism of Nanofluids

    Directory of Open Access Journals (Sweden)

    Mahesh Suresh Patil

    2016-10-01

    Full Text Available Nanofluids are suspended nano-sized particles in a base fluid. With increasing demand for more high efficiency thermal systems, nanofluids seem to be a promising option for researchers. As a result, numerous investigations have been undertaken to understand the behaviors of nanofluids. Since their discovery, the thermo-physical properties of nanofluids have been under intense research. Inadequate understanding of the mechanisms involved in the heat transfer of nanofluids has been the major obstacle for the development of sophisticated nanofluids with the desired properties. In this comprehensive review paper, investigations on synthesis, thermo-physical properties, and heat transfer mechanisms of nanofluids have been reviewed and presented. Results show that the thermal conductivity of nanofluids increases with the increase of the operating temperature. This can potentially be used for the efficiency enhancement of thermal systems under higher operating temperatures. In addition, this paper also provides details concerning dependency of the thermo-physical properties as well as synthesis and the heat transfer mechanism of the nanofluids.

  12. Numerical Modelling of Mechanical Integrity of the Copper-Cast Iron Canister. A Literature Review

    International Nuclear Information System (INIS)

    Lanru Jing

    2004-04-01

    This review article presents a summary of the research works on the numerical modelling of the mechanical integrity of the composite copper-cast iron canisters for the final disposal of Swedish nuclear wastes, conducted by SKB and SKI since 1992. The objective of the review is to evaluate the outstanding issues existing today about the basic design concepts and premises, fundamental issues on processes, properties and parameters considered for the functions and requirements of canisters under the conditions of a deep geological repository. The focus is placed on the adequacy of numerical modelling approaches adopted in regards to the overall mechanical integrity of the canisters, especially the initial state of canisters regarding defects and the consequences of their evolution under external and internal loading mechanisms adopted in the design premises. The emphasis is the stress-strain behaviour and failure/strength, with creep and plasticity involved. Corrosion, although one of the major concerns in the field of canister safety, was not included

  13. The Immunomodulatory Effects of Macrolides—A Systematic Review of the Underlying Mechanisms

    Directory of Open Access Journals (Sweden)

    Petra Zimmermann

    2018-03-01

    Full Text Available BackgroundThe mechanisms underlying the non-antimicrobial immunomodulatory properties of macrolides are not well understood.ObjectivesTo systematically review the evidence for the immunomodulatory properties of macrolides in humans and to describe the underlying mechanism and extent of their influence on the innate and adaptive immune system.MethodsA systematic literature search was done in MEDLINE using the OVID interface from 1946 to December 2016 according to the preferred reporting items for systematic reviews and meta-analysis (PRISMA. Original articles investigating the influence of four macrolides (azithromycin, clarithromycin, erythromycin, and roxithromycin on immunological markers in humans were included.ResultsWe identified 22 randomized, controlled trials, 16 prospective cohort studies, and 8 case–control studies investigating 47 different immunological markers (186 measurements in 1,834 participants. The most frequently reported outcomes were a decrease in the number of neutrophils, and the concentrations of neutrophil elastase, interleukin (IL-8, IL-6, IL-1beta, tumor necrosis factor (TNF-alpha, eosinophilic cationic protein, and matrix metalloproteinase 9. Inhibition of neutrophil function was reported more frequently than eosinophil function. A decrease in T helper (Th 2 cells cytokines (IL-4, IL-5, IL-6 was reported more frequently than a decrease in Th1 cytokines (IL-2, INF-gamma.ConclusionMacrolides influence a broad range of immunological mechanisms resulting in immunomodulatory effects. To optimize the treatment of chronic inflammatory diseases by macrolides, further studies are necessary, particularly comparing different macrolides and dose effect relationships.

  14. Fe–Al–Mn–C lightweight structural alloys: a review on the microstructures and mechanical properties

    Science.gov (United States)

    Kim, Hansoo; Suh, Dong-Woo; Kim, Nack J

    2013-01-01

    Adding a large amount of light elements such as aluminum to steels is not a new concept recalling that several Fe–Al–Mn–C alloys were patented in 1950s for replacement of nickel or chromium in corrosion resistance steels. However, the so-called lightweight steels or low-density steels were revisited recently, which is driven by demands from the industry where steel has served as a major structural material. Strengthening without loss of ductility has been a triumph in steel research, but lowering the density of steel by mixing with light elements will be another prospect that may support the competitiveness against emerging alternatives such as magnesium alloys. In this paper, we review recent studies on lightweight steels, emphasizing the concept of alloy design for microstructures and mechanical properties. The influence of alloying elements on the phase constituents, mechanical properties and the change of density is critically reviewed. Deformation mechanisms of various lightweight steels are discussed as well. This paper provides a reason why the success of lightweight steels is strongly dependent on scientific achievements even though alloy development is closely related to industrial applications. Finally, we summarize some of the main directions for future investigations necessary for vitalizing this field of interest. PMID:27877553

  15. Fe-Al-Mn-C lightweight structural alloys: a review on the microstructures and mechanical properties.

    Science.gov (United States)

    Kim, Hansoo; Suh, Dong-Woo; Kim, Nack J

    2013-02-01

    Adding a large amount of light elements such as aluminum to steels is not a new concept recalling that several Fe-Al-Mn-C alloys were patented in 1950s for replacement of nickel or chromium in corrosion resistance steels. However, the so-called lightweight steels or low-density steels were revisited recently, which is driven by demands from the industry where steel has served as a major structural material. Strengthening without loss of ductility has been a triumph in steel research, but lowering the density of steel by mixing with light elements will be another prospect that may support the competitiveness against emerging alternatives such as magnesium alloys. In this paper, we review recent studies on lightweight steels, emphasizing the concept of alloy design for microstructures and mechanical properties. The influence of alloying elements on the phase constituents, mechanical properties and the change of density is critically reviewed. Deformation mechanisms of various lightweight steels are discussed as well. This paper provides a reason why the success of lightweight steels is strongly dependent on scientific achievements even though alloy development is closely related to industrial applications. Finally, we summarize some of the main directions for future investigations necessary for vitalizing this field of interest.

  16. Lifelong bilingualism and neural reserve against Alzheimer's disease: a review of findings and potential mechanisms.

    Science.gov (United States)

    Gold, Brian T

    2015-03-15

    Alzheimer's disease (AD) is a progressive brain disorder that initially affects medial temporal lobe circuitry and memory functions. Current drug treatments have only modest effects on the symptomatic course of the disease. In contrast, a growing body of evidence suggests that lifelong bilingualism may delay the onset of clinical AD symptoms by several years. The purpose of the present review is to summarize evidence for bilingualism as a reserve variable against AD and discuss potential underlying neurocognitive mechanisms. Evidence is reviewed suggesting that bilingualism may delay clinical AD symptoms by protecting frontostriatal and frontoparietal executive control circuitry rather than medial temporal lobe memory circuitry. Cellular and molecular mechanisms that may contribute to bilingual cognitive reserve effects are discussed, including those that may affect neuronal metabolic functions, dynamic neuronal-glial interactions, vascular factors, myelin structure and neurochemical signaling. Future studies that may test some of these potential mechanisms of bilingual CR effects are proposed. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. A review on mechanical considerations for chronically-implanted neural probes

    Science.gov (United States)

    Lecomte, Aziliz; Descamps, Emeline; Bergaud, Christian

    2018-06-01

    This review intends to present a comprehensive analysis of the mechanical considerations for chronically-implanted neural probes. Failure of neural electrical recordings or stimulation over time has shown to arise from foreign body reaction and device material stability. It seems that devices that match most closely with the mechanical properties of the brain would be more likely to reduce the mechanical stress at the probe/tissue interface, thus improving body acceptance. The use of low Young’s modulus polymers instead of hard substrates is one way to enhance this mechanical mimetism, though compliance can be achieved through a variety of means. The reduction of probe width and thickness in comparison to a designated length, the use of soft hydrogel coatings and the release in device tethering to the skull, can also improve device compliance. Paradoxically, the more compliant the device, the more likely it will fail during the insertion process in the brain. Strategies have multiplied this past decade to offer partial or temporary stiffness to the device to overcome this buckling effect. A detailed description of the probe insertion mechanisms is provided to analyze potential sources of implantation failure and the need for a mechanically-enhancing structure. This leads us to present an overview of the strategies that have been put in place over the last ten years to overcome buckling issues. Particularly, great emphasis is put on bioresorbable polymers and their assessment for neural applications. Finally, a discussion is provided on some of the key features for the design of mechanically-reliable, polymer-based next generation of chronic neuroprosthetic devices.

  18. Exercise Equipment: Neutral Buoyancy

    Science.gov (United States)

    Shackelford, Linda; Valle, Paul

    2016-01-01

    Load Bearing Equipment for Neutral Buoyancy (LBE-NB) is an exercise frame that holds two exercising subjects in position as they apply counter forces to each other for lower extremity and spine loading resistance exercises. Resistance exercise prevents bone loss on ISS, but the ISS equipment is too massive for use in exploration craft. Integrating the human into the load directing, load generating, and motion control functions of the exercise equipment generates safe exercise loads with less equipment mass and volume.

  19. BP volume reduction equipment

    International Nuclear Information System (INIS)

    Kitamura, Yoshinori; Muroo, Yoji; Hamanaka, Isao

    2003-01-01

    A new type of burnable poison (BP) volume reduction system is currently being developed. Many BP rods, a subcomponent of spent fuel assemblies are discharged from nuclear power reactors. This new system reduces the overall volume of BP rods. The main system consists of BP rod cutting equipment, equipment for the recovery of BP cut pieces, and special transport equipment for the cut rods. The equipment is all operated by hydraulic press cylinders in water to reduce operator exposure to radioactivity. (author)

  20. Methods and equipments used in power reactors

    International Nuclear Information System (INIS)

    Beraha, R.; Delevallee, A.

    1976-01-01

    The various reactor γ fuel scanning facilities presently operating around the world are reviewed. Both equipments proposed by FRAMATOME are described: one is intended for scanning removable fuel pencils, and the other one for fuel assembly scanning [fr

  1. Insights into carbon nanotube and graphene formation mechanisms from molecular simulations: a review

    International Nuclear Information System (INIS)

    Page, A J; Ding, F; Irle, S; Morokuma, K

    2015-01-01

    The discovery of carbon nanotubes (CNTs) and graphene over the last two decades has heralded a new era in physics, chemistry and nanotechnology. During this time, intense efforts have been made towards understanding the atomic-scale mechanisms by which these remarkable nanostructures grow. Molecular simulations have made significant contributions in this regard; indeed, they are responsible for many of the key discoveries and advancements towards this goal. Here we review molecular simulations of CNT and graphene growth, and in doing so we highlight the many invaluable insights gained from molecular simulations into these complex nanoscale self-assembly processes. This review highlights an often-overlooked aspect of CNT and graphene formation—that the two processes, although seldom discussed in the same terms, are in fact remarkably similar. Both can be viewed as a 0D → 1D → 2D transformation, which converts carbon atoms (0D) to polyyne chains (1D) to a complete sp 2 -carbon network (2D). The difference in the final structure (CNT or graphene) is determined only by the curvature of the catalyst and the strength of the carbon–metal interaction. We conclude our review by summarizing the present shortcomings of CNT/graphene growth simulations, and future challenges to this important area. (review article)

  2. A review of proton exchange membrane water electrolysis on degradation mechanisms and mitigation strategies

    Science.gov (United States)

    Feng, Qi; Yuan, Xiao-Zi; Liu, Gaoyang; Wei, Bing; Zhang, Zhen; Li, Hui; Wang, Haijiang

    2017-10-01

    Proton exchange membrane water electrolysis (PEMWE) is an advanced and effective solution to the primary energy storage technologies. A better understanding of performance and durability of PEMWE is critical for the engineers and researchers to further advance this technology for its market penetration, and for the manufacturers of PEM water electrolyzers to implement quality control procedures for the production line or on-site process monitoring/diagnosis. This paper reviews the published works on performance degradations and mitigation strategies for PEMWE. Sources of degradation for individual components are introduced. With degradation causes discussed and degradation mechanisms examined, the review emphasizes on feasible strategies to mitigate the components degradation. To avoid lengthy real lifetime degradation tests and their high costs, the importance of accelerated stress tests and protocols is highlighted for various components. In the end, R&D directions are proposed to move the PEMWE technology forward to become a key element in future energy scenarios.

  3. Enhancement and Optimization Mechanisms of Biogas Production for Rural Household Energy in Developing Countries: A review

    Directory of Open Access Journals (Sweden)

    Yitayal Addis Alemayehu

    2015-10-01

    Full Text Available Anaerobic digestion is common but vital process used for biogas and fertilizer production as well as one method for waste treatment. The process is currently used in developing countries primarily for biogas production in the household level of rural people. The aim of this review is to indicate possible ways of including rural households who own less than four heads of cattle for the biogas programs in developing countries. The review provides different research out puts on using biogas substrates other than cow dung or its mix through different enhancement and optimization mechanisms. Many biodegradable materials have been studied for alternative methane production. Therefore, these substrates could be used for production by addressing the optimum conditions for each factor and each processes for enhanced and optimized biogas production.

  4. Reliability and Measurement Error of Tensiomyography to Assess Mechanical Muscle Function: A Systematic Review.

    Science.gov (United States)

    Martín-Rodríguez, Saúl; Loturco, Irineu; Hunter, Angus M; Rodríguez-Ruiz, David; Munguia-Izquierdo, Diego

    2017-12-01

    Martín-Rodríguez, S, Loturco, I, Hunter, AM, Rodríguez-Ruiz, D, and Munguia-Izquierdo, D. Reliability and measurement error of tensiomyography to assess mechanical muscle function: A systematic review. J Strength Cond Res 31(12): 3524-3536, 2017-Interest in studying mechanical skeletal muscle function through tensiomyography (TMG) has increased in recent years. This systematic review aimed to (a) report the reliability and measurement error of all TMG parameters (i.e., maximum radial displacement of the muscle belly [Dm], contraction time [Tc], delay time [Td], half-relaxation time [½ Tr], and sustained contraction time [Ts]) and (b) to provide critical reflection on how to perform accurate and appropriate measurements for informing clinicians, exercise professionals, and researchers. A comprehensive literature search was performed of the Pubmed, Scopus, Science Direct, and Cochrane databases up to July 2017. Eight studies were included in this systematic review. Meta-analysis could not be performed because of the low quality of the evidence of some studies evaluated. Overall, the review of the 9 studies involving 158 participants revealed high relative reliability (intraclass correlation coefficient [ICC]) for Dm (0.91-0.99); moderate-to-high ICC for Ts (0.80-0.96), Tc (0.70-0.98), and ½ Tr (0.77-0.93); and low-to-high ICC for Td (0.60-0.98), independently of the evaluated muscles. In addition, absolute reliability (coefficient of variation [CV]) was low for all TMG parameters except for ½ Tr (CV = >20%), whereas measurement error indexes were high for this parameter. In conclusion, this study indicates that 3 of the TMG parameters (Dm, Td, and Tc) are highly reliable, whereas ½ Tr demonstrate insufficient reliability, and thus should not be used in future studies.

  5. Electric utility engineer`s FGD manual -- Volume 2: Major mechanical equipment; FGD proposal evaluations; Use of FGDPRISM in FGD system modification, proposal, evaluation, and design; FGD system case study. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-04

    Part 2 of this manual provides the electric utility engineer with detailed technical information on some of the major mechanical equipment used in the FGD system. The objectives of Part 2 are the following: to provide the electric utility engineer with information on equipment that may be unfamiliar to him, including ball mills, vacuum filters, and mist eliminators; and to identify the unique technique considerations imposed by an FGD system on more familiar electric utility equipment such as fans, gas dampers, piping, valves, and pumps. Part 3 provides an overview of the recommended procedures for evaluating proposals received from FGD system vendors. The objectives are to provide procedures for evaluating the technical aspects of proposals, and to provide procedures for determining the total costs of proposals considering both initial capital costs and annual operating and maintenance costs. The primary objective of Part 4 of this manual is to provide the utility engineer who has a special interest in the capabilities of FGDPRISM [Flue Gas Desulfurization PRocess Integration and Simulation Model] with more detailed discussions of its uses, requirements, and limitations. Part 5 is a case study in using this manual in the preparation of a purchase specification and in the evaluation of proposals received from vendors. The objectives are to demonstrate how the information contained in Parts 1 and 2 can be used to improve the technical content of an FGD system purchase specification; to demonstrate how the techniques presented in Part 3 can be used to evaluate proposals received in response to the purchase specification; and to illustrate how the FGDPRISM computer program can be used to establish design parameters for the specification and evaluate vendor designs.

  6. Annual review of numerical fluid mechanics and heat transfer. Volume 1

    International Nuclear Information System (INIS)

    Chawla, T.C.

    1987-01-01

    Numerical techniqes for the analysis of problems in fluid mechanics and heat transfer are discussed, reviewing the results of recent investigations. Topics addressed include thermal radiation in particulate media with dependent and independent scattering, pressure-velocity coupling in incompressiblefluid flow, new explicit methods for diffusion problems, and one-dimensional reaction-diffusion equations in combustion theory. Consideration is given to buckling flows, multidimensional radiative-transfer analysis in participating media, freezing and melting problems, and complex heat-transfer processes in heat-generating horizontal fluid layers

  7. TiO$_2$-based Memristors and ReRAM: Materials, Mechanisms and Models (a Review)

    OpenAIRE

    Gale, Ella

    2016-01-01

    The memristor is the fundamental non-linear circuit element, with uses in computing and computer memory. ReRAM (Resistive Random Access Memory) is a resistive switching memory proposed as a non-volatile memory. In this review we shall summarise the state of the art for these closely-related fields, concentrating on titanium dioxide, the well-utilised and archetypal material for both. We shall cover material properties, switching mechanisms and models to demonstrate what ReRAM and memristor sc...

  8. MECHANISMS IN ENDOCRINOLOGY: Diabetic cardiomyopathy: pathophysiology and potential metabolic interventions state of the art review.

    Science.gov (United States)

    Levelt, Eylem; Gulsin, Gaurav; Neubauer, Stefan; McCann, Gerry P

    2018-04-01

    Heart failure is a major cause of morbidity and mortality in type 2 diabetes. Type 2 diabetes contributes to the development of heart failure through a variety of mechanisms, including disease-specific myocardial structural, functional and metabolic changes. This review will focus on the contemporary contributions of state of the art non-invasive technologies to our understanding of diabetic cardiomyopathy, including data on cardiac disease phenotype, cardiac energy metabolism and energetic deficiency, ectopic and visceral adiposity, diabetic liver disease, metabolic modulation strategies and cardiovascular outcomes with new classes of glucose-lowering therapies. © 2018 The authors.

  9. The analysis of actuating mechanism and review of concepts for the vortex valve

    International Nuclear Information System (INIS)

    Park, Jong Kyun; Sim, Yun Seop; Joung, Sae Won; Lee, Ki Young; Lee, Jun; Kim, Young In

    1995-12-01

    To understand the basic features of the passive fluidic device, which is increasing available core cooling water from the safety injection tanks in the KNGR, review of the existing vortex valves concepts and analysis of the actuating mechanism of them have been performed and the results are as following: * Preliminary methodology development for parallel two water columns behavior, which is similar to the SIT valve actuation condition * Preliminary methodology for the vortex value actuation features * Analysis of the parallel water columns behavior and vortex valve actuation features using the results of above activities * Further works to be done in the analytical methodology. 16 figs., 2 refs. (Author) .new

  10. Effects and mechanisms of a microcurrent dressing on skin wound healing: a review.

    Science.gov (United States)

    Yu, Chao; Hu, Zong-Qian; Peng, Rui-Yun

    2014-01-01

    The variety of wound types has resulted in a wide range of wound dressings, with new products frequently being introduced to target different aspects of the wound healing process. The ideal wound dressing should achieve rapid healing at a reasonable cost, with minimal inconvenience to the patient. Microcurrent dressing, a novel wound dressing with inherent electric activity, can generate low-level microcurrents at the device-wound contact surface in the presence of moisture and can provide an advanced wound healing solution for managing wounds. This article offers a review of the effects and mechanisms of the microcurrent dressing on the healing of skin wounds.

  11. Serotonin reuptake inhibitors and bone health: A review of clinical studies and plausible mechanisms

    Directory of Open Access Journals (Sweden)

    Ravisha Wadhwa

    2017-06-01

    Full Text Available Selective serotonin reuptake inhibitors (SSRIs are currently the treatment of choice in depression and constitute major portion of prescription in depressive patients. The role of serotonin receptors in bone is emerging, raising certain questions regarding the effect of blockade of serotonin reuptake in the bone metabolism. Clinical studies have reported an association of SSRI antidepressants which with increase in fracture and decrease in bone mineral density. This review focus on recent evidence that evaluate the association of SSRIs with the risk of fracture and bone mineral density and also the probable mechanisms that might be involved in such effects.

  12. TiO2-based memristors and ReRAM: materials, mechanisms and models (a review)

    Science.gov (United States)

    Gale, Ella

    2014-10-01

    The memristor is the fundamental nonlinear circuit element, with uses in computing and computer memory. Resistive Random Access Memory (ReRAM) is a resistive switching memory proposed as a non-volatile memory. In this review we shall summarize the state of the art for these closely-related fields, concentrating on titanium dioxide, the well-utilized and archetypal material for both. We shall cover material properties, switching mechanisms and models to demonstrate what ReRAM and memristor scientists can learn from each other and examine the outlook for these technologies.

  13. Advanced paternal age effects in neurodevelopmental disorders-review of potential underlying mechanisms.

    Science.gov (United States)

    Janecka, M; Mill, J; Basson, M A; Goriely, A; Spiers, H; Reichenberg, A; Schalkwyk, L; Fernandes, C

    2017-01-31

    Multiple epidemiological studies suggest a relationship between advanced paternal age (APA) at conception and adverse neurodevelopmental outcomes in offspring, particularly with regard to increased risk for autism and schizophrenia. Conclusive evidence about how age-related changes in paternal gametes, or age-independent behavioral traits affect neural development is still lacking. Recent evidence suggests that the origins of APA effects are likely to be multidimensional, involving both inherited predisposition and de novo events. Here we provide a review of the epidemiological and molecular findings to date. Focusing on the latter, we present the evidence for genetic and epigenetic mechanisms underpinning the association between late fatherhood and disorder in offspring. We also discuss the limitations of the APA literature. We propose that different hypotheses relating to the origins of the APA effects are not mutually exclusive. Instead, multiple mechanisms likely contribute, reflecting the etiological complexity of neurodevelopmental disorders.

  14. Effect of Nanoparticle Incorporation and Surface Coating on Mechanical Properties of Bone Scaffolds: A Brief Review

    Directory of Open Access Journals (Sweden)

    Jesus Corona-Gomez

    2016-07-01

    Full Text Available Mechanical properties of a scaffold play an important role in its in vivo performance in bone tissue engineering, due to the fact that implanted scaffolds are typically subjected to stress including compression, tension, torsion, and shearing. Unfortunately, not all the materials used to fabricate scaffolds are strong enough to mimic native bones. Extensive research has been conducted in order to increase scaffold strength and mechanical performance by incorporating nanoparticles and/or coatings. An incredible improvement has been achieved; and some outstanding examples are the usage of nanodiamond, hydroxyapatite, bioactive glass particles, SiO2, MgO, and silver nanoparticles. This review paper aims to present the results, to summarize significant findings, and to give perspective for future work, which could be beneficial to future bone tissue engineering.

  15. Mechanical, Thermal, and Electrical Properties of Graphene-Epoxy Nanocomposites—A Review

    Directory of Open Access Journals (Sweden)

    Rasheed Atif

    2016-08-01

    Full Text Available Monolithic epoxy, because of its brittleness, cannot prevent crack propagation and is vulnerable to fracture. However, it is well established that when reinforced—especially by nano-fillers, such as metallic oxides, clays, carbon nanotubes, and other carbonaceous materials—its ability to withstand crack propagation is propitiously improved. Among various nano-fillers, graphene has recently been employed as reinforcement in epoxy to enhance the fracture related properties of the produced epoxy–graphene nanocomposites. In this review, mechanical, thermal, and electrical properties of graphene reinforced epoxy nanocomposites will be correlated with the topographical features, morphology, weight fraction, dispersion state, and surface functionalization of graphene. The factors in which contrasting results were reported in the literature are highlighted, such as the influence of graphene on the mechanical properties of epoxy nanocomposites. Furthermore, the challenges to achieving the desired performance of polymer nanocomposites are also suggested throughout the article.

  16. Concise Review: Bone Marrow for the Treatment of Spinal Cord Injury: Mechanisms and Clinical Applications

    Science.gov (United States)

    Wright, Karina T; Masri, Wagih El; Osman, Aheed; Chowdhury, Joy; Johnson, William E B

    2011-01-01

    Transplantation of bone marrow stem cells into spinal cord lesions enhances axonal regeneration and promotes functional recovery in animal studies. There are two types of adult bone marrow stem cell; hematopoietic stem cells (HSCs), and mesenchymal stem cells (MSCs). The mechanisms by which HSCs and MSCs might promote spinal cord repair following transplantation have been extensively investigated. The objective of this review is to discuss these mechanisms; we briefly consider the controversial topic of HSC and MSC transdifferentiation into central nervous system cells but focus on the neurotrophic, tissue sparing, and reparative action of MSC grafts in the context of the spinal cord injury (SCI) milieu. We then discuss some of the specific issues related to the translation of HSC and MSC therapies for patients with SCI and present a comprehensive critique of the current bone marrow cell clinical trials for the treatment of SCI to date. Stem Cells 2011;29:169–178 PMID:21732476

  17. Review on Characterization and Mechanical Performance of Self-cleaning Concrete

    Directory of Open Access Journals (Sweden)

    Zailan Siti Norsaffirah

    2017-01-01

    Full Text Available Self-cleaning concrete is an effective alternative to provide cleaner environment which contribute to sustainability and towards a green environment. It is in accordance with the requirements of environmental issues on huge energy consumption and air pollution from carbon dioxide (CO2 emissions. Photocatalyst in self-cleaning concrete accelerates the decomposition of organic particulates, hence pollution could be reduced through photocatalytic degradation of gaseous pollutants. Mechanical performances of self-cleaning concrete were improved by adding photocatalytic materials. Self cleaning abilities were evaluated in the photocatalytic activity test under UV light and photocatalytic degradation of gaseous pollutant was measured by depollution test. This review aims to give an overview about the characteristics of photocatalytic materials and mechanical performances of self-cleaning concrete.

  18. Electrical equipment qualification

    International Nuclear Information System (INIS)

    Farmer, W.S.

    1983-01-01

    Electrical equipment qualification research programs being carried out by CEA, JAERI, and Sandia Laboratories are discussed. Objectives of the program are: (1) assessment of accident simulation methods for electrical equipment qualification testing; lower coarse (2) evaluation of equipment aging and accelerated aging methods; (3) determine radiation dose spectrum to electrical equipment and assess simulation methods for qualification; (4) identify inadequacies in electrical equipment qualification procedures and standards and potential failure modes; and (5) provide data for verifying and improving standards, rules and regulatory guides

  19. The Difference Between Countermovement and Squat Jump Performances: A Review of Underlying Mechanisms With Practical Applications.

    Science.gov (United States)

    Van Hooren, Bas; Zolotarjova, Julia

    2017-07-01

    Van Hooren, B and Zolotarjova, J. The difference between countermovement and squat jump performances: a review of underlying mechanisms with practical applications. J Strength Cond Res 31(7): 2011-2020, 2017-Two movements that are widely used to monitor athletic performance are the countermovement jump (CMJ) and squat jump (SJ). Countermovement jump performance is almost always better than SJ performance, and the difference in performance is thought to reflect an effective utilization of the stretch-shortening cycle. However, the mechanisms responsible for the performance-enhancing effect of the stretch-shortening cycle are frequently undefined. Uncovering and understanding these mechanisms is essential to make an inference regarding the difference between the jumps. Therefore, we will review the potential mechanisms that explain the better performance in a CMJ as compared with a SJ. It is concluded that the difference in performance may primarily be related to the greater uptake of muscle slack and the buildup of stimulation during the countermovement in a CMJ. Elastic energy may also have a small contribution to an enhanced CMJ performance. Therefore, a larger difference between the jumps is not necessarily a better indicator of high-intensity sports performance. Although a larger difference may reflect the utilization of elastic energy in a small-amplitude CMJ as a result of a well-developed capability to co-activate muscles and quickly build up stimulation, a larger difference may also reflect a poor capability to reduce the degree of muscle slack and build up stimulation in the SJ. Because the capability to reduce the degree of muscle slack and quickly build up stimulation in the SJ may be especially important to high-intensity sports performance, training protocols might concentrate on attaining a smaller difference between the jumps.

  20. BASEBALL THROWING MECHANICS AS THEY RELATE TO PATHOLOGY AND PERFORMANCE - A REVIEW

    Directory of Open Access Journals (Sweden)

    Rod Whiteley

    2007-03-01

    Full Text Available It is a commonly held perception amongst biomechanists, sports medicine practitioners, baseball coaches and players, that an individual baseball player's style of throwing or pitching influences their performance and susceptibility to injury. With the results of a series of focus groups with baseball managers and pitching coaches in mind, the available scientific literature was reviewed regarding the contribution of individual aspects of pitching and throwing mechanics to potential for injury and performance. After a discussion of the limitations of kinematic and kinetic analyses, the individual aspects of pitching mechanics are discussed under arbitrary headings: Foot position at stride foot contact; Elbow flexion; Arm rotation; Arm horizontal abduction; Arm abduction; Lead knee position; Pelvic orientation; Deceleration-phase related issues; Curveballs; and Teaching throwing mechanics. In general, popular opinion of baseball coaching staff was found to be largely in concordance with the scientific investigations of biomechanists with several notable exceptions. Some difficulties are identified with the practical implementation of analyzing throwing mechanics in the field by pitching coaches, and with some unquantified aspects of scientific analyses

  1. Mechanisms of spinal cord injury regeneration in zebrafish: a systematic review

    Directory of Open Access Journals (Sweden)

    Zeynab Noorimotlagh

    2017-12-01

    Full Text Available Objective(s:To determine the molecular and cellular mechanisms of spinal cord regeneration in zebrafish. Materials and Methods: Medical databases of PubMed and Scopus were searched with following key words: Zebrafish; spinal cord injuries; regeneration; recovery of function. The map of mechanisms was performed using Xmind software. Results: Wnt/ß-catenin signaling, L1.1, L1.2, Major vault protein (MVP, contactin-2 and High mobility group box1 (HMGB1 had positive promoting effects on axonal re-growth while Ptena had an inhibitory effect. Neurogenesis is stimulated by Wnt/ß-catenin signaling as well as HMGB1, but inhibited by Notch signaling. Glial cells proliferate in response to fibroblast growth factor (fgf signaling and Lysophosphatidic acid (LPA. Furthermore, fgf signaling pathway causes glia bridge formation in favor of axonal regeneration. LPA and HMGB1 in acute phase stimulate inflammatory responses around injury and suppress regeneration. LPA also induces microglia activation and neuronal death in addition to glia cell proliferation, but prevents neurite sprouting. Conclusion: This study provides a comprehensive review of the known molecules and mechanisms in the current literature involved in the spinal cord injury (SCI regeneration in zebrafish, in a time course manner. A better understanding of the whole determining mechanisms for the SCI regeneration should be considered as a main goal for future studies.

  2. AVM branch vibration test equipment

    International Nuclear Information System (INIS)

    Anne, J.P.

    1995-01-01

    An inventory of the test equipment of the AVM Branch ''Acoustic and Vibratory Mechanics Analysis Methods'' group has been undertaken. The purpose of this inventory is to enable better acquaintance with the technical characteristics of the equipment, providing an accurate definition of their functionalities, ad to inform potential users of the possibilities and equipment available in this field. The report first summarizes the various experimental surveys conduced. Then, using the AVM equipment database to draw up an exhaustive list of available equipment, it provides a full-scope picture of the vibration measurement systems (sensors, conditioners and exciters) and data processing resources commonly used on industrial sites and in laboratories. A definition is also given of a mobile test unit, called 'shelter', and a test bench used for the testing and performance rating of the experimental analysis methods developed by the group. The report concludes with a description of two fixed installations: - the calibration bench ensuring the requisite quality level for the vibration measurement systems ; - the training bench, whereby know-how acquired in the field in the field of measurement and experimental analysis processes is made available to others. (author). 27 refs., 15 figs., 2 appends

  3. Space Heating Equipment

    Energy Technology Data Exchange (ETDEWEB)

    Rafferty, Kevin D.

    1998-01-01

    The performance evaluation of space heating equipment for a geothermal application is generally considered from either of two perspectives: (a) selecting equipment for installation in new construction, or (b) evaluating the performance and retrofit requirements of an existing system. With regard to new construction, the procedure is relatively straightforward. Once the heating requirements are determined, the process need only involve the selection of appropriately sized hot water heating equipment based on the available water temperature. It is important to remember that space heating equipment for geothermal applications is the same equipment used in non-geothermal applications. What makes geothermal applications unique is that the equipment is generally applied at temperatures and flow rates that depart significantly from traditional heating system design. This chapter presents general considerations for the performance of heating equipment at non-standard temperature and flow conditions, retrofit of existing systems, and aspects of domestic hot water heating.

  4. Renewal of radiological equipment.

    Science.gov (United States)

    2014-10-01

    In this century, medical imaging is at the heart of medical practice. Besides providing fast and accurate diagnosis, advances in radiology equipment offer new and previously non-existing options for treatment guidance with quite low morbidity, resulting in the improvement of health outcomes and quality of life for the patients. Although rapid technological development created new medical imaging modalities and methods, the same progress speed resulted in accelerated technical and functional obsolescence of the same medical imaging equipment, consequently creating a need for renewal. Older equipment has a high risk of failures and breakdowns, which might cause delays in diagnosis and treatment of the patient, and safety problems both for the patient and the medical staff. The European Society of Radiology is promoting the use of up-to-date equipment, especially in the context of the EuroSafe Imaging Campaign, as the use of up-to-date equipment will improve quality and safety in medical imaging. Every healthcare institution or authority should have a plan for medical imaging equipment upgrade or renewal. This plan should look forward a minimum of 5 years, with annual updates. Teaching points • Radiological equipment has a definite life cycle span, resulting in unavoidable breakdown and decrease or loss of image quality which renders equipment useless after a certain time period.• Equipment older than 10 years is no longer state-of-the art equipment and replacement is essential. Operating costs of older equipment will be high when compared with new equipment, and sometimes maintenance will be impossible if no spare parts are available.• Older equipment has a high risk of failure and breakdown, causing delays in diagnosis and treatment of the patient and safety problems both for the patient and the medical staff.• Every healthcare institution or authority should have a plan for medical imaging equipment upgrade or replacement. This plan should look forward a

  5. Mechanical properties of copper processed by Equal Channel Angular Pressing – a review

    Directory of Open Access Journals (Sweden)

    Ludvík Kunz

    2012-01-01

    Full Text Available The Equal Channel Angular Pressing is a hardening treatment with which ductile metals can be processed to refine their grain and sub-grain structure. This process enhances the mechanical strength of metals in terms of tensile strength, stress-controlled fatigue strength, and fatigue crack growth resistance. In this paper the authors draw a review of the major results of a wide research activity they carried out on a copper microstructure processed by Equal Channel Angular Pressing. The essential results are that tensile and fatigue strengths of the so obtained refined structure are improved by a factor of two with respect to the original coarse-grained metal. The fatigue crack initiation mechanism and the stability of the refined microstructure under cyclic loading are topics also discussed, evidencing the essential role of the process and of the material parameter, as the content of impurities in the microstructure. In this review, the authors also underline some critical aspects that have to be more investigated.

  6. Trauma and the psychosis spectrum: A review of symptom specificity and explanatory mechanisms

    Science.gov (United States)

    Gibson, Lauren E.; Alloy, Lauren B.; Ellman, Lauren M.

    2016-01-01

    Traumatic life events have been robustly associated with various psychosis outcomes, including increased risk of psychotic disorders, the prodrome of psychosis, and dimensional measures of psychotic symptoms, such as attenuated positive psychotic symptoms. However, trauma exposure has been linked to various mental disorders; therefore, the specificity of trauma exposure to psychosis remains unclear. This review focuses on two understudied areas of the trauma and psychosis literature: 1) the specificity between trauma and psychosis in relation to other disorders that often result post-trauma, and 2) proposed mechanisms that uniquely link trauma to psychosis. We begin by discussing the underlying connection between trauma exposure and the entire psychosis spectrum with a focus on the influence of trauma type and specific psychotic symptoms. We then consider how the principles of multifinality and equifinality can be useful in elucidating the trauma-psychosis relationship versus the trauma-other disorder relationship. Next, we discuss several cognitive and neurobiological mechanisms that might uniquely account for the association between trauma and psychosis, as well as the role of gender. Lastly, we review important methodological issues that complicate the research on trauma and psychosis, ending with clinical implications for the field. PMID:27632064

  7. The effectiveness of neuromuscular warm-up strategies, that require no additional equipment, for preventing lower limb injuries during sports participation: a systematic review.

    Science.gov (United States)

    Herman, Katherine; Barton, Christian; Malliaras, Peter; Morrissey, Dylan

    2012-07-19

    Lower limb injuries in sport are increasingly prevalent and responsible for large economic as well as personal burdens. In this review we seek to determine which easily implemented functional neuromuscular warm-up strategies are effective in preventing lower limb injuries during sports participation and in which sporting groups they are effective. Seven electronic databases were searched from inception to January 2012 for studies investigating neuromuscular warm-up strategies and injury prevention. The quality of each included study was evaluated using a modified version of the van Tulder scale. Data were extracted from each study and used to calculate the risk of injury following application of each evaluated strategy. Nine studies were identified including six randomized controlled trials (RCT) and three controlled clinical trials (CCT). Heterogeneity in study design and warm-up strategies prevented pooling of results. Two studies investigated male and female participants, while the remaining seven investigated women only. Risk Ratio (RR) statistics indicated 'The 11+' prevention strategy significantly reduces overall (RR 0.67, confidence interval (CI) 0.54 to 0.84) and overuse (RR 0.45, CI 0.28 to 0.71) lower limb injuries as well as knee (RR 0.48, CI 0.32 to 0.72) injuries among young amateur female footballers. The 'Knee Injury Prevention Program' (KIPP) significantly reduced the risk of noncontact lower limb (RR 0.5, CI 0.33 to 0.76) and overuse (RR 0.44, CI 0.22 to 0.86) injuries in young amateur female football and basketball players. The 'Prevent Injury and Enhance Performance' (PEP) strategy reduces the incidence of anterior cruciate ligament (ACL) injuries (RR 0.18, CI 0.08 to 0.42). The 'HarmoKnee' programme reduces the risk of knee injuries (RR 0.22, CI 0.06 to 0.76) in teenage female footballers. The 'Anterior Knee Pain Prevention Training Programme' (AKP PTP) significantly reduces the incidence of anterior knee pain (RR 0.27, CI 0.14 to 0.54) in

  8. The effectiveness of neuromuscular warm-up strategies, that require no additional equipment, for preventing lower limb injuries during sports participation: a systematic review

    Directory of Open Access Journals (Sweden)

    Herman Katherine

    2012-07-01

    Full Text Available Abstract Background Lower limb injuries in sport are increasingly prevalent and responsible for large economic as well as personal burdens. In this review we seek to determine which easily implemented functional neuromuscular warm-up strategies are effective in preventing lower limb injuries during sports participation and in which sporting groups they are effective. Methods Seven electronic databases were searched from inception to January 2012 for studies investigating neuromuscular warm-up strategies and injury prevention. The quality of each included study was evaluated using a modified version of the van Tulder scale. Data were extracted from each study and used to calculate the risk of injury following application of each evaluated strategy. Results Nine studies were identified including six randomized controlled trials (RCT and three controlled clinical trials (CCT. Heterogeneity in study design and warm-up strategies prevented pooling of results. Two studies investigated male and female participants, while the remaining seven investigated women only. Risk Ratio (RR statistics indicated 'The 11+' prevention strategy significantly reduces overall (RR 0.67, confidence interval (CI 0.54 to 0.84 and overuse (RR 0.45, CI 0.28 to 0.71 lower limb injuries as well as knee (RR 0.48, CI 0.32 to 0.72 injuries among young amateur female footballers. The 'Knee Injury Prevention Program' (KIPP significantly reduced the risk of noncontact lower limb (RR 0.5, CI 0.33 to 0.76 and overuse (RR 0.44, CI 0.22 to 0.86 injuries in young amateur female football and basketball players. The 'Prevent Injury and Enhance Performance' (PEP strategy reduces the incidence of anterior cruciate ligament (ACL injuries (RR 0.18, CI 0.08 to 0.42. The 'HarmoKnee' programme reduces the risk of knee injuries (RR 0.22, CI 0.06 to 0.76 in teenage female footballers. The 'Anterior Knee Pain Prevention Training Programme' (AKP PTP significantly reduces the incidence of anterior

  9. Income inequality and depression: a systematic review and meta‐analysis of the association and a scoping review of mechanisms

    Science.gov (United States)

    Patel, Vikram; Burns, Jonathan K.; Dhingra, Monisha; Tarver, Leslie; Kohrt, Brandon A.; Lund, Crick

    2018-01-01

    Most countries have witnessed a dramatic increase of income inequality in the past three decades. This paper addresses the question of whether income inequality is associated with the population prevalence of depression and, if so, the potential mechanisms and pathways which may explain this association. Our systematic review included 26 studies, mostly from high‐income countries. Nearly two‐thirds of all studies and five out of six longitudinal studies reported a statistically significant positive relationship between income inequality and risk of depression; only one study reported a statistically significant negative relationship. Twelve studies were included in a meta‐analysis with dichotomized inequality groupings. The pooled risk ratio was 1.19 (95% CI: 1.07‐1.31), demonstrating greater risk of depression in populations with higher income inequality relative to populations with lower inequality. Multiple studies reported subgroup effects, including greater impacts of income inequality among women and low‐income populations. We propose an ecological framework, with mechanisms operating at the national level (the neo‐material hypothesis), neighbourhood level (the social capital and the social comparison hypotheses) and individual level (psychological stress and social defeat hypotheses) to explain this association. We conclude that policy makers should actively promote actions to reduce income inequality, such as progressive taxation policies and a basic universal income. Mental health professionals should champion such policies, as well as promote the delivery of interventions which target the pathways and proximal determinants, such as building life skills in adolescents and provision of psychological therapies and packages of care with demonstrated effectiveness for settings of poverty and high income inequality. PMID:29352539

  10. Income inequality and depression: a systematic review and meta-analysis of the association and a scoping review of mechanisms.

    Science.gov (United States)

    Patel, Vikram; Burns, Jonathan K; Dhingra, Monisha; Tarver, Leslie; Kohrt, Brandon A; Lund, Crick

    2018-02-01

    Most countries have witnessed a dramatic increase of income inequality in the past three decades. This paper addresses the question of whether income inequality is associated with the population prevalence of depression and, if so, the potential mechanisms and pathways which may explain this association. Our systematic review included 26 studies, mostly from high-income countries. Nearly two-thirds of all studies and five out of six longitudinal studies reported a statistically significant positive relationship between income inequality and risk of depression; only one study reported a statistically significant negative relationship. Twelve studies were included in a meta-analysis with dichotomized inequality groupings. The pooled risk ratio was 1.19 (95% CI: 1.07-1.31), demonstrating greater risk of depression in populations with higher income inequality relative to populations with lower inequality. Multiple studies reported subgroup effects, including greater impacts of income inequality among women and low-income populations. We propose an ecological framework, with mechanisms operating at the national level (the neo-material hypothesis), neighbourhood level (the social capital and the social comparison hypotheses) and individual level (psychological stress and social defeat hypotheses) to explain this association. We conclude that policy makers should actively promote actions to reduce income inequality, such as progressive taxation policies and a basic universal income. Mental health professionals should champion such policies, as well as promote the delivery of interventions which target the pathways and proximal determinants, such as building life skills in adolescents and provision of psychological therapies and packages of care with demonstrated effectiveness for settings of poverty and high income inequality. © 2018 World Psychiatric Association.

  11. Fundamental mechanisms and reactions in non-catalytic subcritical hydrothermal processes: A review.

    Science.gov (United States)

    Yousefifar, Azadeh; Baroutian, Saeid; Farid, Mohammed M; Gapes, Daniel J; Young, Brent R

    2017-10-15

    The management and disposal of solid waste is of increasing concern across the globe. Hydrothermal processing of sludge has been suggested as a promising solution to deal with the considerable amounts of sludge produced worldwide. Such a process not only degrades organic compounds and reduces waste volume, but also provides an opportunity to recover valuable substances. Hydrothermal processing comprises two main sub-processes: wet oxidation (WO) and thermal hydrolysis (TH), in which the formation of various free radicals results in the production of different intermediates. Volatile fatty acids (VFAs), especially acetic acid, are usually the main intermediates which remain as a by-product of the process. This paper aims to review the fundamental mechanism for hydrothermal processing of sludge, and the formation of different free radicals and intermediates therein. In addition, the proposed kinetic models for the two processes (WO and TH) from the literature are reviewed and the advantages and disadvantages of each model are outlined. The effect of mass transfer as a critical component of the design and development of the processes, which has been neglected in most of these proposed models, is also reviewed, and the effect of influencing parameters on the processes' controlling step (reaction or mass transfer) is discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Efficacy of inter-dental mechanical plaque control in managing gingivitis--a meta-review.

    Science.gov (United States)

    Sälzer, Sonja; Slot, Dagmar E; Van der Weijden, Fridus A; Dörfer, Christof E

    2015-04-01

    What is the effect of mechanical inter-dental plaque removal in addition to toothbrushing, on managing gingivitis using various formats of inter-dental self-care in adults based on evidence gathered from existing systematic reviews? Three Internet sources were searched by a strategy designed to include systematic reviews on inter-dental cleaning devices. Plaque and gingivitis scores were the primary parameters of interest. Characteristics of selected papers were extracted. The potential risk of bias was estimated and the acquired evidence was graded. Screening of 395 papers resulted in six systematic reviews. Two papers evaluated the efficacy of dental floss, two of inter-dental brushes (IDB), one of woodsticks and one of the oral irrigator. Weak evidence of unclear or small magnitude was retrieved that supported dental floss, woodsticks and the oral irrigator to reduce gingivitis in addition to toothbrushing. No concomitant evidence for an effect on plaque emerged. There is moderate evidence that IDBs in combination with toothbrushing reduce both plaque and gingivitis. Evidence suggests that inter-dental cleaning with IDBs is the most effective method for inter-dental plaque removal. The majority of available studies fail to demonstrate that flossing is generally effective in plaque removal. All investigated devices for inter-dental self-care seem to support the management of gingivitis, however, to a varying extend. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  13. Overview of reviews: mechanical interventions for the treatment and management of chronic obstructive pulmonary disease.

    Science.gov (United States)

    Lisy, Karolina; White, Heath; Pearson, Alan

    2014-12-01

    Chronic obstructive pulmonary disease (COPD) is characterized by a progressive and non-reversible airflow limitation and symptoms of breathlessness, sputum production and cough. COPD is the fourth most common cause of mortality worldwide and represents a significant social and economic burden. As such, effective strategies that might be employed to treat COPD and manage symptoms need to be investigated. This overview aimed to summarize the existing evidence available in the Cochrane Library regarding the use of mechanical interventions used for the treatment and management of COPD. Systematic reviews that included adult participants with diagnosed COPD who received a mechanical intervention were included. Five reviews were included, and due to the heterogeneity of these reviews, direct and indirect comparisons of the effects of the intervention were not possible. Instead, data of the effectiveness of each intervention were extracted and summarized in tables and discussed as a narrative summary. Interventions included non-invasive positive pressure ventilation (NPPV), positive airway pressure (PEP) devices and neuromuscular electrical stimulation (NMES). Evidence regarding the effectiveness of NPPV was limited, and available data do not support the use of NPPV for patients with stable COPD. NPPV might, however, be of benefit as a weaning strategy for intubated patients and for patients experiencing respiratory failure; however, more research is required. Although PEP devices are considered as a safe airway clearance technique, data do not reveal a clear clinical benefit to their use. NMES is also regarded as safe for patients with COPD, and might also be beneficial in improving exercise tolerance and improving quality of life for patients with COPD. © 2014 Wiley Publishing Asia Pty Ltd.

  14. Relationship between sleep duration and childhood obesity: Systematic review including the potential underlying mechanisms.

    Science.gov (United States)

    Felső, R; Lohner, S; Hollódy, K; Erhardt, É; Molnár, D

    2017-09-01

    The prevalence of obesity is continually increasing worldwide. Determining risk factors for obesity may facilitate effective preventive programs. The present review focuses on sleep duration as a potential risk factor for childhood obesity. The aim is to summarize the evidence on the association of sleep duration and obesity and to discuss the underlying potential physiological and/or pathophysiological mechanisms. The Ovid MEDLINE, Scopus and Cochrane Central Register of Controlled Trials (CENTRAL) databases were searched for papers using text words with appropriate truncation and relevant indexing terms. All studies objectively measuring sleep duration and investigating the association between sleep duration and obesity or factors (lifestyle and hormonal) possibly associated with obesity were included, without making restrictions based on study design or language. Data from eligible studies were extracted in tabular form and summarized narratively. After removing duplicates, 3540 articles were obtained. Finally, 33 studies (including 3 randomized controlled trials and 30 observational studies) were included in the review. Sleep duration seems to influence weight gain in children, however, the underlying explanatory mechanisms are still uncertain. In our review only the link between short sleep duration and the development of insulin resistance, sedentarism and unhealthy dietary patterns could be verified, while the role of other mediators, such as physical activity, screen time, change in ghrelin and leptin levels, remained uncertain. There are numerous evidence gaps. To answer the remaining questions, there is a need for studies meeting high methodological standards and including a large number of children. Copyright © 2017 The Italian Society of Diabetology, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition, and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All

  15. The mechanisms of far transfer from cognitive training: Review and hypothesis.

    Science.gov (United States)

    Greenwood, Pamela M; Parasuraman, Raja

    2016-09-01

    General intelligence is important for success in daily life, fueling interest in developing cognitive training as an intervention to improve fluid ability (Gf). A major obstacle to the design of effective cognitive interventions has been the paucity of hypotheses bearing on mechanisms underlying transfer of cognitive training to Gf. Despite the large amounts of money and time currently being expended on cognitive training, there is little scientific agreement on how, or even whether, Gf can be heightened by such training. We review the relevant strands of evidence on cognitive-training-related changes in (a) cortical mechanisms of distraction suppression, and (b) activation of the dorsal attention network (DAN). We hypothesize that training-related increases in control of attention are important for what is termed far transfer of cognitive training to untrained abilities, notably to Gf. We review the evidence that distraction suppression evident in behavior, neuronal firing, scalp electroencephalography, and hemodynamic change is important for protecting target processing during perception and also for protecting targets held in working memory. Importantly, attentional control also appears to be central to performance on Gf assessments. Consistent with this evidence, forms of cognitive training that increase ability to ignore distractions (e.g., working memory training and perceptual training) not only affect the DAN but also affect transfer to Gf. Our hypothesis is supported by existing evidence. However, to advance the field of cognitive training, it is necessary that competing hypotheses on mechanisms of far transfer of cognitive training be advanced and empirically tested. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  16. A review of mechanical and tribological behaviour of polymer composite materials

    Science.gov (United States)

    Prabhakar, K.; Debnath, S.; Ganesan, R.; Palanikumar, K.

    2018-04-01

    Composite materials are finding increased applications in many industrial applications. A nano-composite is a matrix to which nanosized particles have been incorporated to drastically improve the mechanical performance of the original material. The structural components produced using nano-composites will exhibit a high strength-to-weight ratio. The properties of nano-composites have caused researchers and industries to consider using this material in several fields. Polymer nanocomposites consists of a polymer material having nano-particles or nano-fillers dispersed in the polymer matrix which may be of different shapes with at least one of the dimensions less than 100nm. In this paper, comprehensive review of polymer nanocomposites was done majorly in three different areas. First, mechanical behaviour of polymer nanocomposites which focuses on the mechanical property evaluation such as tensile strength, impact strength and modulus of elasticity based on the different combination of filler materials and nanoparticle inclusion. Second, wear behavior of Polymer composite materials with respect to different impingement angles and variation of filler composition using different processing techniques. Third, tribological (Friction and Wear) behaviour of nanocomposites using various combination of nanoparticle inclusion and time. Finally, it summarized the challenges and prospects of polymer nanocomposites.

  17. Additively Manufactured Scaffolds for Bone Tissue Engineering and the Prediction of their Mechanical Behavior: A Review.

    Science.gov (United States)

    Zhang, Xiang-Yu; Fang, Gang; Zhou, Jie

    2017-01-10

    Additive manufacturing (AM), nowadays commonly known as 3D printing, is a revolutionary materials processing technology, particularly suitable for the production of low-volume parts with high shape complexities and often with multiple functions. As such, it holds great promise for the fabrication of patient-specific implants. In recent years, remarkable progress has been made in implementing AM in the bio-fabrication field. This paper presents an overview on the state-of-the-art AM technology for bone tissue engineering (BTE) scaffolds, with a particular focus on the AM scaffolds made of metallic biomaterials. It starts with a brief description of architecture design strategies to meet the biological and mechanical property requirements of scaffolds. Then, it summarizes the working principles, advantages and limitations of each of AM methods suitable for creating porous structures and manufacturing scaffolds from powdered materials. It elaborates on the finite-element (FE) analysis applied to predict the mechanical behavior of AM scaffolds, as well as the effect of the architectural design of porous structure on its mechanical properties. The review ends up with the authors' view on the current challenges and further research directions.

  18. Mechanisms Underlying the Analgesic Effect of Moxibustion on Visceral Pain in Irritable Bowel Syndrome: A Review

    Directory of Open Access Journals (Sweden)

    Renjia Huang

    2014-01-01

    Full Text Available Irritable bowel syndrome (IBS is a functional bowel disorder that causes recurrent abdominal (visceral pain. Epidemiological data show that the incidence rate of IBS is as high as 25%. Most of the medications may lead to tolerance, addiction and toxic side effects. Moxibustion is an important component of traditional Chinese medicine and has been used to treat IBS-like abdominal pain for several thousand years in China. As a mild treatment, moxibustion has been widely applied in clinical treatment of visceral pain in IBS. In recent years, it has played an irreplaceable role in alternative medicine. Extensive clinical studies have demonstrated that moxibustion for treatment of visceral pain is simple, convenient, and inexpensive, and it is being accepted by an increasing number of patients. There have not been many studies investigating the analgesic mechanisms of moxibustion. Studies exploring the analgesic mechanisms have mainly focused on visceral hypersensitivity, brain-gut axis neuroendocrine system, and immune system. This paper reviews the latest developments in moxibustion use for treatment of visceral pain in IBS from these perspectives. It also evaluates potential problems in relevant studies on the mechanisms of moxibustion therapy to promote the application of moxibustion in the treatment of IBS.

  19. The Role of Malware in Reported Cyber Espionage: A Review of the Impact and Mechanism

    Directory of Open Access Journals (Sweden)

    Gaute Wangen

    2015-05-01

    Full Text Available The recent emergence of the targeted use of malware in cyber espionage versus industry requires a systematic review for better understanding of its impact and mechanism. This paper proposes a basic taxonomy to document major cyber espionage incidents, describing and comparing their impacts (geographic or political targets, origins and motivations and their mechanisms (dropper, propagation, types of operating systems and infection rates. This taxonomy provides information on recent cyber espionage attacks that can aid in defense against cyber espionage by providing both scholars and experts a solid foundation of knowledge about the topic. The classification also provides a systematic way to document known and future attacks to facilitate research activities. Geopolitical and international relations researchers can focus on the impacts, and malware and security experts can focus on the mechanisms. We identify several dominant patterns (e.g., the prevalent use of remote access Trojan and social engineering. This article concludes that the research and professional community should collaborate to build an open data set to facilitate the geopolitical and/or technical analysis and synthesis of the role of malware in cyber espionage.

  20. A review of the effect of vital teeth bleaching on the mechanical properties of tooth enamel.

    Science.gov (United States)

    Elfallah, Hunida M; Swain, Michael V

    2013-09-01

    Tooth whitening is considered the easiest and most cost-effective procedure for treating tooth discoloration. Contemporary bleaching agents contain hydrogen peroxide as the active ingredient. It is either applied directly or produced from its precursor, carbamide peroxide. A review of the published literature was undertaken to investigate the potential adverse effects of whitening products on dental enamel, with a focus on its mechanical properties and the influence of various parameters on study outcomes. There appear to be considerable differences in opinion as to whether changes in mechanical properties occur as a result of tooth whitening. However, the mechanical property findings of those studies appear to be related to the load applied during the indentation tests. Most studies which used loads higher than 500mN to determine enamel hardness showed no effect of bleaching, whereas those using lower loads were able to detect hardness reduction in the surface layer of enamel. In conclusion, bleaching reduces the hardness of the enamel surface of enamel, and that is more readily detected with instrumented low load testing systems. This hardness reduction may arise due to degradation or denaturation of enamel matrix proteins by the peroxide oxidation.

  1. Review article: anti-inflammatory mechanisms of action of Saccharomyces boulardii.

    Science.gov (United States)

    Pothoulakis, C

    2009-10-15

    Saccharomyces boulardii, a well-studied probiotic, can be effective in inflammatory gastrointestinal diseases with diverse pathophysiology, such as inflammatory bowel disease (IBD), and bacterially mediated or enterotoxin-mediated diarrhoea and inflammation. To discuss the mechanisms of action involved in the intestinal anti-inflammatory action of S. boulardii. Review of the literature related to the anti-inflammatory effects of this probiotic. Several mechanisms of action have been identified directed against the host and pathogenic microorganisms. S. boulardii and S. boulardii secreted-protein(s) inhibit production of proinflammatory cytokines by interfering with the global mediator of inflammation nuclear factor kappaB, and modulating the activity of the mitogen-activated protein kinases ERK1/2 and p38. S. boulardii activates expression of peroxisome proliferator-activated receptor-gamma (PPAR-gamma) that protects from gut inflammation and IBD. S. boulardii also suppresses 'bacteria overgrowth' and host cell adherence, releases a protease that cleaves C. difficile toxin A and its intestinal receptor and stimulates antibody production against toxin A. Recent results indicate that S. boulardii may interfere with IBD pathogenesis by trapping T cells in mesenteric lymph nodes. The multiple anti-inflammatory mechanisms exerted by S. boulardii provide molecular explanations supporting its effectiveness in intestinal inflammatory states.

  2. Review article: Anti-inflammatory mechanisms of action of Saccharomyces boulardii

    Science.gov (United States)

    Pothoulakis, C.

    2009-01-01

    SUMMARY Background Saccharomyces boulardii (S. boulardii), a well-studied probiotic, can be effective in inflammatory gastrointestinal diseases with diverse pathophysiology, such as Inflammatory Bowel Disease (IBD), and bacterially – or enterotoxin-mediated diarrhea and inflammation. Aim Discuss the mechanisms of action involved in the intestinal anti-inflammatory action of S. boulardii Methods Review of the literature related to the anti-inflammatory effects of this probiotic. Results Several mechanisms of action have been identified directed against the host and pathogenic microorganisms. S. boulardii and S. boulardii secreted protein(s) inhibit production of proinflammatory cytokines by interfering with the global mediator of inflammation nuclear factor κB, and modulating the activity of the mitogen-activated protein kinases ERK1/2 and p38. S. boulardii activates expression of peroxisome proliferator-activated receptor-gamma (PPAR-γ) that protects from gut inflammation and IBD. S. boulardii also suppresses “bacteria overgrowth” and host cell adherence, releases a protease that cleaves C. difficile toxin A and its intestinal receptor, and stimulates antibody production against toxin A. Recent results indicate that S. boulardii may interfere with IBD pathogenesis by trapping T cells in mesenteric lymph nodes. Conclusions The multiple anti-inflammatory mechanisms exerted by S. boulardii provide molecular explanations supporting its effectiveness in intestinal inflammatory states. PMID:19706150

  3. Maintenance program guidelines for programmatic equipment

    International Nuclear Information System (INIS)

    1994-11-01

    The Division Directors at Lawrence Berkeley Laboratory are responsible for implementing a maintenance program for research equipment (also referred to as programmatic equipment) assigned to them. The program must allow maintenance to be accomplished in a manner that promotes operational safety, environmental protection and compliance, and cost effectiveness; that preserves the intended functions of the facilities and equipment; and that supports the programmatic mission of the Laboratory. Programmatic equipment -- such as accelerators, lasers, radiation detection equipment, and glove boxes -- is dedicated specifically to research. Installed equipment, by contrast, includes the mechanical and electrical systems installed as part of basic building construction, equipment essential to the normal functioning of the facility and its intended use. Examples of installed equipment are heating, ventilating, and air conditioning systems; elevators; and communications systems. The LBL Operating and Assurance Program Plan (PUB-3111, Revision 4) requires that a maintenance program be prepared for programmatic equipment and defines the basic maintenance program elements. Such a program of regular, documented maintenance is vital to the safety and quality of research activities. As a part of that support, this document offers guidance to Laboratory organizations for developing their maintenance programs. It clarifies the maintenance requirements of the Operating and Assurance Program (OAP) and presents an approach that, while not the only possibility, can be expected to produce an effective maintenance program for research equipment belonging to the Laboratory's organizations

  4. RETRIEVAL EQUIPMENT DESCRIPTIONS

    International Nuclear Information System (INIS)

    J. Steinhoff

    1997-01-01

    The objective and the scope of this document are to list and briefly describe the major mobile equipment necessary for waste package (WP) retrieval from the proposed subsurface nuclear waste repository at Yucca Mountain. Primary performance characteristics and some specialized design features of the equipment are explained and summarized in the individual subsections of this document. There are no quality assurance requirements or QA controls in this document. Retrieval under normal conditions is accomplished with the same fleet of equipment as is used for emplacement. Descriptions of equipment used for retrieval under normal conditions is found in Emplacement Equipment Descriptions, DI: BCAF00000-01717-5705-00002 (a document in progress). Equipment used for retrieval under abnormal conditions is addressed in this document and consists of the following: (1) Inclined Plane Hauler; (2) Bottom Lift Transporter; (3) Load Haul Dump (LHD) Loader; (4) Heavy Duty Forklift for Emplacement Drifts; (5) Covered Shuttle Car; (6) Multipurpose Vehicle; and (7) Scaler

  5. A strategy for implementation of experience based seismic equipment qualification in IEEE and ASME industry standards

    International Nuclear Information System (INIS)

    Adams, T.M.

    1996-01-01

    In the past 20 years, extensive data on the performance of mechanical and electric equipment during actual strong motion earthquakes and seismic qualification tests has been accumulated. Recognizing that an experience based approach provides a technically sound and cost effective method for the seismic qualification of some or certain equipment, the IEEE Nuclear Power Engineering Committee and the ASME Committee on Qualification of Mechanical Equipment established a Special Working Group to investigate the incorporation of experienced based methods into the industry consensus codes and standards currently used in the seismic qualification of Seismic Category Nuclear Power Plant equipment. This paper presents the strategy (course of action) which was developed by the Special Working Group for meeting this objective of incorporation of experience based seismic qualification standards used in the design and seismic qualification of seismic category nuclear power plant equipment. This strategy was recommended to both chartering organizations, the IEEE Nuclear Power Engineering Committee and the ASME Committee on Qualification of Mechanical Equipment for their consideration and implementation. The status of the review and implementation of the Special Working Group's recommended strategy by the sponsoring organization is also discussed

  6. Review of Real-Time 3-Dimensional Image Guided Radiation Therapy on Standard-Equipped Cancer Radiation Therapy Systems: Are We at the Tipping Point for the Era of Real-Time Radiation Therapy?

    Science.gov (United States)

    Keall, Paul J; Nguyen, Doan Trang; O'Brien, Ricky; Zhang, Pengpeng; Happersett, Laura; Bertholet, Jenny; Poulsen, Per R

    2018-04-14

    To review real-time 3-dimensional (3D) image guided radiation therapy (IGRT) on standard-equipped cancer radiation therapy systems, focusing on clinically implemented solutions. Three groups in 3 continents have clinically implemented novel real-time 3D IGRT solutions on standard-equipped linear accelerators. These technologies encompass kilovoltage, combined megavoltage-kilovoltage, and combined kilovoltage-optical imaging. The cancer sites treated span pelvic and abdominal tumors for which respiratory motion is present. For each method the 3D-measured motion during treatment is reported. After treatment, dose reconstruction was used to assess the treatment quality in the presence of motion with and without real-time 3D IGRT. The geometric accuracy was quantified through phantom experiments. A literature search was conducted to identify additional real-time 3D IGRT methods that could be clinically implemented in the near future. The real-time 3D IGRT methods were successfully clinically implemented and have been used to treat more than 200 patients. Systematic target position shifts were observed using all 3 methods. Dose reconstruction demonstrated that the delivered dose is closer to the planned dose with real-time 3D IGRT than without real-time 3D IGRT. In addition, compromised target dose coverage and variable normal tissue doses were found without real-time 3D IGRT. The geometric accuracy results with real-time 3D IGRT had a mean error of real-time 3D IGRT methods using standard-equipped radiation therapy systems that could also be clinically implemented. Multiple clinical implementations of real-time 3D IGRT on standard-equipped cancer radiation therapy systems have been demonstrated. Many more approaches that could be implemented were identified. These solutions provide a pathway for the broader adoption of methods to make radiation therapy more accurate, impacting tumor and normal tissue dose, margins, and ultimately patient outcomes. Copyright © 2018

  7. Effects of Heat Input on Microstructure, Corrosion and Mechanical Characteristics of Welded Austenitic and Duplex Stainless Steels: A Review

    Directory of Open Access Journals (Sweden)

    Ghusoon Ridha Mohammed

    2017-01-01

    Full Text Available The effects of input heat of different welding processes on the microstructure, corrosion, and mechanical characteristics of welded duplex stainless steel (DSS are reviewed. Austenitic stainless steel (ASS is welded using low-heat inputs. However, owing to differences in the physical metallurgy between ASS and DSS, low-heat inputs should be avoided for DSS. This review highlights the differences in solidification mode and transformation characteristics between ASS and DSS with regard to the heat input in welding processes. Specifically, many studies about the effects of heat energy input in welding process on the pitting corrosion, intergranular stress, stresscorrosion cracking, and mechanical properties of weldments of DSS are reviewed.

  8. Medical equipment management

    CERN Document Server

    Willson, Keith; Tabakov, Slavik

    2013-01-01

    Know What to Expect When Managing Medical Equipment and Healthcare Technology in Your Organization As medical technology in clinical care becomes more complex, clinical professionals and support staff must know how to keep patients safe and equipment working in the clinical environment. Accessible to all healthcare professionals and managers, Medical Equipment Management presents an integrated approach to managing medical equipment in healthcare organizations. The book explains the underlying principles and requirements and raises awareness of what needs to be done and what questions to ask. I

  9. Data communication equipment

    International Nuclear Information System (INIS)

    Kim, Hak Seon; Lee, Sang Mok

    1998-02-01

    The contents of this book are introduction of data communication on definition, purpose and history, information terminal about data communication system and data transmission system, data transmit equipment of summary, transmission cable, data port, concentrator and front-end processor, audio communication equipment like phones, radio communication equipment of summary on foundation of electromagnetic waves, AM transmitter, AM receiver, FM receiver and FM transmitter, a satellite and mobile communication equipment such as earth station, TT and C and Cellular phone, video telephone and new media apparatus.

  10. A comprehensive review on self-healing of asphalt materials: Mechanism, model, characterization and enhancement.

    Science.gov (United States)

    Sun, Daquan; Sun, Guoqiang; Zhu, Xingyi; Guarin, Alvaro; Li, Bin; Dai, Ziwei; Ling, Jianming

    2018-05-09

    Self-healing has great potential to extend the service life of asphalt pavement, and this capability has been regarded as an important strategy when designing a sustainable infrastructure. This review presents a comprehensive summary of the state-of-the-art investigations concerning the self-healing mechanism, model, characterization and enhancement, ranging from asphalt to asphalt pavement. Firstly, the self-healing phenomenon as a general concept in asphalt materials is analyzed including its definition and the differences among self-healing and some viscoelastic responses. Additionally, the development of self-healing in asphalt pavement design is introduced. Next, four kinds of possible self-healing mechanism and corresponding models are presented. It is pointed out that the continuum thermodynamic model, considering the whole process from damage initiation to healing recovery, can be a promising study field. Further, a set of self-healing multiscale characterization methods from microscale to macroscale as well as computational simulation scale, are summed up. Thereinto, the computational simulation shows great potential in simulating the self-healing behavior of asphalt materials from mechanical and molecular level. Moreover, the factors influencing self-healing capability are discussed, but the action mechanisms of some factors remain unclear and need to be investigated. Finally, two extrinsic self-healing technologies, induction heating and capsule healing, are recommended as preventive maintenance applications in asphalt pavement. In future, more effective energy-based healing systems or novel material-based healing systems are expected to be developed towards designing sustainable long-life asphalt pavement. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Market-based mechanisms for biodiversity conservation: a review of existing schemes and an outline for a global mechanism

    NARCIS (Netherlands)

    Alvarado Quesada, I.; Hein, L.G.; Weikard, H.P.

    2014-01-01

    Continuous decline of biodiversity over the past decades suggests that efforts to decrease biodiversity loss have been insufficient. One option to deal with this problem is the use of market-based mechanisms for biodiversity conservation. Several studies have analysed such mechanisms individually,

  12. The Complementary and Alternative Medicine for Endometriosis: A Review of Utilization and Mechanism

    Directory of Open Access Journals (Sweden)

    Sai Kong

    2014-01-01

    Full Text Available Endometriosis (EM is one of the common gynecological conditions causing menstrual and pelvic pain and affects 10%–15% of women of reproductive age. In recent years, the complementary and alternative medical (CAM treatment for EM has become popular due to the few adverse reactions reported. The CAM therapy for EM includes several different treatments such as herbs (herbal prescription, extract, and patent, acupuncture, microwave physiotherapy, and Chinese herb medicine enema (CHM enema. These CAM therapies are effective at relieving dysmenorrhoea, shrinking adnexal masses, and promoting pregnancy, with less unpleasant side effects when compared to hormonal and surgical treatments. In this review, we focus on the status quo of CAM on EM and try to identify therapeutic efficacy and mechanisms based on some clinical and experimental studies. We hope to provide some instructive suggestions for clinical treatment and experimental research in the future.

  13. [Effects of biochar on soil nitrogen cycle and related mechanisms: a review].

    Science.gov (United States)

    Pan, Yi-Fan; Yang, Min; Dong, Da; Wu, Wei-Xiang

    2013-09-01

    Biochar has its unique physical and chemical properties, playing a significant role in soil amelioration, nutrient retention, fertility improvement, and carbon storage, and being a hotspot in the research areas of soil ecosystem, biogeochemical cycling, and agricultural carbon sequestration. As a kind of anthropogenic materials, biochar has the potential in controlling soil nitrogen (N) cycle directly or indirectly, and thus, has profound effects on soil ecological functions. This paper reviewed the latest literatures regarding the effects of biochar applications on soil N cycle, with the focuses on the nitrogen species adsorption and the biochemical processes (nitrification, denitrification, and nitrogen fixation) , and analyzed the related action mechanisms of biochar. The future research areas for better understanding the interactions between biochar and soil N cycle were proposed.

  14. Critical review on the physical and mechanical factors involved in tissue engineering of cartilage.

    Science.gov (United States)

    Gaut, Carrie; Sugaya, Kiminobu

    2015-01-01

    Articular cartilage defects often progress to osteoarthritis, which negatively impacts quality of life for millions of people worldwide and leads to high healthcare expenditures. Tissue engineering approaches to osteoarthritis have concentrated on proliferation and differentiation of stem cells by activation and suppression of signaling pathways, and by using a variety of scaffolding techniques. Recent studies indicate a key role of environmental factors in the differentiation of mesenchymal stem cells to mature cartilage-producing chondrocytes. Therapeutic approaches that consider environmental regulation could optimize chondrogenesis protocols for regeneration of articular cartilage. This review focuses on the effect of scaffold structure and composition, mechanical stress and hypoxia in modulating mesenchymal stem cell fate and the current use of these environmental factors in tissue engineering research.

  15. Knee mechanics during planned and unplanned sidestepping: a systematic review and meta-analysis.

    Science.gov (United States)

    Brown, Scott R; Brughelli, Matt; Hume, Patria A

    2014-11-01

    Knee joint mechanics during sidestepping are associated with anterior cruciate ligament injury. Unplanned sidestepping more closely emulates game scenarios when compared with planned sidestepping by limiting decision time, increasing knee loading and challenging the integrity of soft-tissue structures in the knee. It is important to quantify the loads that may challenge the integrity of the knee during planned and unplanned sidestepping. Our objective was to review literature on knee mechanics during planned and unplanned phases of sidestepping. PubMed, CINAHL, MEDLINE (EBSCO), SPORTDiscus and Web of Science were searched using the terms knee mechanics OR knee kine*, AND plan*, unplan*, anticipat*, unanticipat*, side*, cut* or chang*. A systematic approach was used to evaluate 4,629 records. Records were excluded when not available in English, only available in abstract of conference proceedings, not involving a change-of-direction sidestep, not comparing planned and unplanned or maintaining a running velocity greater than 2 m s(−1). Included studies were evaluated independently by two authors using a custom-designed methodological quality assessment derived from the Physiotherapy Evidence Database (PEDro) scale and then confirmed by a third author. Only six studies met the inclusion criteria and were retained for meta-analysis. Magnitude-based inferences were used to assess the standardised effect of the differences between planned and unplanned sidestepping. Knee angles and knee moments were extracted and reported for flexion/extension, abduction/adduction and internal/external rotation for initial contact, weight acceptance, peak push-off and final push-off phases of sidestepping. For kinematic variables, unplanned sidestepping produced a wide range of small to large increases in knee extension angles, small and moderate increases in knee abduction angles and a small increase in internal rotation angle relative to planned sidestepping during the sidestepping

  16. Causes and Mechanisms of Intrauterine Hypoxia and Its Impact on the Fetal Cardiovascular System: A Review

    Directory of Open Access Journals (Sweden)

    Damian Hutter

    2010-01-01

    Full Text Available Until today the role of oxygen in the development of the fetus remains controversially discussed. It is still believed that lack of oxygen in utero might be responsible for some of the known congenital cardiovascular malformations. Over the last two decades detailed research has given us new insights and a better understanding of embryogenesis and fetal growth. But most importantly it has repeatedly demonstrated that oxygen only plays a minor role in the early intrauterine development. After organogenesis has taken place hypoxia becomes more important during the second and third trimester of pregnancy when fetal growth occurs. This review will briefly adress causes and mechanisms leading to intrauterine hypoxia and their impact on the fetal cardiovascular system.

  17. Consumer sleep tracking devices: a review of mechanisms, validity and utility.

    Science.gov (United States)

    Kolla, Bhanu Prakash; Mansukhani, Subir; Mansukhani, Meghna P

    2016-05-01

    Consumer sleep tracking devices such as fitness trackers and smartphone apps have become increasingly popular. These devices claim to measure the sleep duration of their users and in some cases purport to measure sleep quality and awaken users from light sleep, potentially improving overall sleep. Most of these devices appear to utilize data generated from in-built accelerometers to determine sleep parameters but the exact mechanisms and algorithms are proprietary. The growing literature comparing these devices against polysomnography/actigraphy shows that they tend to underestimate sleep disruptions and overestimate total sleep times and sleep efficiency in normal subjects. In this review, we evaluate the current literature comparing the accuracy of consumer sleep tracking devices against more conventional methods used to measure sleep duration and quality. We discuss the current technology that these devices utilize as well as summarize the value of these devices in clinical evaluations and their potential limitations.

  18. Understanding Central Mechanisms of Acupuncture Analgesia Using Dynamic Quantitative Sensory Testing: A Review

    Directory of Open Access Journals (Sweden)

    Jiang-Ti Kong

    2013-01-01

    Full Text Available We discuss the emerging translational tools for the study of acupuncture analgesia with a focus on psychophysical methods. The gap between animal mechanistic studies and human clinical trials of acupuncture analgesia calls for effective translational tools that bridge neurophysiological data with meaningful clinical outcomes. Temporal summation (TS and conditioned pain modulation (CPM are two promising tools yet to be widely utilized. These psychophysical measures capture the state of the ascending facilitation and the descending inhibition of nociceptive transmission, respectively. We review the basic concepts and current methodologies underlying these measures in clinical pain research, and illustrate their application to research on acupuncture analgesia. Finally, we highlight the strengths and limitations of these research methods and make recommendations on future directions. The appropriate addition of TS and CPM to our current research armamentarium will facilitate our efforts to elucidate the central analgesic mechanisms of acupuncture in clinical populations.

  19. [On-line processing mechanisms in text comprehension: a theoretical review on constructing situation models].

    Science.gov (United States)

    Iseki, Ryuta

    2004-12-01

    This article reviewed research on construction of situation models during reading. To position variety of research in overall process appropriately, an unitary framework was devised in terms of three theories for on-line processing: resonance process, event-indexing model, and constructionist theory. Resonance process was treated as a basic activation mechanism in the framework. Event-indexing model was regarded as a screening system which selected and encoded activated information in situation models along with situational dimensions. Constructionist theory was considered to have a supervisory role based on coherence and explanation. From a view of the unitary framework, some problems concerning each theory were examined and possible interpretations were given. Finally, it was pointed out that there were little theoretical arguments on associative processing at global level and encoding text- and inference-information into long-term memory.

  20. Lead toxicity in rice: effects, mechanisms, and mitigation strategies--a mini review.

    Science.gov (United States)

    Ashraf, Umair; Kanu, Adam Sheka; Mo, Zhaowen; Hussain, Saddam; Anjum, Shakeel Ahmad; Khan, Imran; Abbas, Rana Nadeem; Tang, Xiangru

    2015-12-01

    Lead (Pb) is a major environmental pollutant that affects plant morpho-physiological and biochemical attributes. Its higher levels in the environment are not only toxic to human beings but also harmful for plants and soil microbes. We have reviewed the uptake, translocation, and accumulation mechanisms of Pb and its toxic effects on germination, growth, yield, nutrient relation, photosynthesis, respiration, oxidative damage, and antioxidant defense system of rice. Lead toxicity hampers rice germination, root/shoot length, growth, and final yield. It reduces nutrient uptake through roots, disrupts chloroplastic ultrastructure and cell membrane permeability, induces alterations in leaves respiratory activities, produces reactive oxygen species (ROS), and triggers some enzyme and non-enzymatic antioxidants (as defense to oxidative damage). In the end, biochar amendments and phytoremediation technologies have been proposed as soil remediation approaches for Pb tainted soils.

  1. PROMSYS, Plant Equipment Maintenance and Inspection Scheduling

    International Nuclear Information System (INIS)

    Morgan, D.L.; Srite, B.E.

    1986-01-01

    1 - Description of problem or function: PROMSYS is a computer system designed to automate the scheduling of routine maintenance and inspection of plant equipment. This 'programmed maintenance' provides the detailed planning and accomplishment of lubrication, inspection, and similar repetitive maintenance activities which can be scheduled at specified predetermined intervals throughout the year. The equipment items included are the typical pumps, blowers, motors, compressors, automotive equipment, refrigeration units, filtering systems, machine shop equipment, cranes, elevators, motor-generator sets, and electrical switchgear found throughout industry, as well as cell ventilation, shielding, containment, and material handling equipment unique to nuclear research and development facilities. Four related programs are used to produce sorted schedule lists, delinquent work lists, and optional master lists. Five additional programs are used to create and maintain records of all scheduled and unscheduled maintenance history. 2 - Method of solution: Service specifications and frequency are established and stored. The computer program reviews schedules weekly and prints, on schedule cards, instructions for service that is due the following week. The basic output from the computer program comes in two forms: programmed-maintenance schedule cards and programmed-maintenance data sheets. The data sheets can be issued in numerical building, route, and location number sequence as equipment lists, grouped for work assigned to a particular foreman as the foreman's equipment list, or grouped by work charged to a particular work order as the work-order list. Data sheets grouped by equipment classification are called the equipment classification list

  2. Diabetic ketoacidosis: risk factors, mechanisms and management strategies in sub-Saharan Africa: a review.

    Science.gov (United States)

    Otieno, C F; Kayima, J K; Omonge, E O; Oyoo, G O

    2005-12-01

    Diabetic ketoacidosis is the most common hyperglycaemic emergency in patients with diabetes mellitus, especially type 1 diabetes. It carries very high mortality in sub-Saharan Africa, both in the treated patients and those who are presenting to hospital with diabetes for the first time. To review the risk factors, mechanisms and management approaches in diabetes ketoacidosis in published literature and to discuss them in the context of why a significant proportion of patients who develop diabetic ketoacidosis in sub-Saharan Africa still have high mortality. Literature review of relevant published literature from both Africa and the rest of the world. The main causes or precipitants of DKA in patients in SSA are newly diagnosed diabetes, missed insulin doses and infections. The major underlying mechanism is insulin deficiency. Treated patients miss insulin doses for various reasons, for example, inaccessibility occasioned by; unavailability and unaffordability of insulin, missed clinics, perceived ill-health and alternative therapies like herbs, prayers and rituals. Infections also occur quite often, but are not overt, like urinary tract, tuberculosis and pneumonia. Due to widespread poverty of individuals and nations alike, the healthcare systems are scarce and the few available centres are unable to adequately maintain a reliable system of insulin supply and exhaustively investigate their hospitalised patients. Consequently, there is little guarantee of successful outcomes. Poor people may also have sub-optimal nutrition, caused or worsened by diabetes, more so, at first presentation to hospital. Intensive insulin therapy in such individuals mimics 're-feeding syndrome', an acute anabolic state whose outcome may be unfavourable during the period of treatment of diabetic ketoacidosis. Although mortality and morbidity from diabetic ketoacidosis remains high in sub-Saharan Africa, improved healthcare systems and reliable insulin supply can reverse the trend, at least

  3. Mechanics

    CERN Document Server

    Hartog, J P Den

    1961-01-01

    First published over 40 years ago, this work has achieved the status of a classic among introductory texts on mechanics. Den Hartog is known for his lively, discursive and often witty presentations of all the fundamental material of both statics and dynamics (and considerable more advanced material) in new, original ways that provide students with insights into mechanical relationships that other books do not always succeed in conveying. On the other hand, the work is so replete with engineering applications and actual design problems that it is as valuable as a reference to the practicing e

  4. Cooling of electronic equipment

    DEFF Research Database (Denmark)

    A. Kristensen, Anders Schmidt

    2003-01-01

    Cooling of electronic equipment is studied. The design size of electronic equipment decrease causing the thermal density to increase. This affect the cooling which can cause for example failures of critical components due to overheating or thermal induced stresses. Initially a pin fin heat sink...

  5. Acute Pancreatitis after Percutaneous Mechanical Thrombectomy: Case Report and Review of the Literature

    International Nuclear Information System (INIS)

    Hershberger, Richard C.; Bornak, Arash; Aulivola, Bernadette; Mannava, Krishna

    2011-01-01

    Purpose: We describe a case of severe acute pancreatitis after percutaneous mechanical thrombectomy (PMT) and review the literature for the occurrence of this complication. Materials and Methods: A 53-year-old man with a history of bilateral external iliac artery stent placement sought care for acute onset of lifestyle-limiting left claudication. Angiography confirmed left external iliac stent occlusion, and PMT with the AngioJet Xpeedior catheter (Possis Medical, Minneapolis MN) was performed. Results: After PMT of the occluded external iliac artery, a residual in-stent stenosis required the placement of a second iliac stent. The procedure was complicated by severe acute pancreatitis. Other causes of pancreatitis were eliminated during the patient’s hospital stay. A literature review revealed nine cases of acute pancreatitis after PMT. Conclusion: Although rare, pancreatitis can be a devastating complication of PMT. The development of pancreatitis seems to be related to the products of extensive hemolysis triggering an inflammatory process. To prevent this complication, we recommend that close attention be paid to the duration and extent of PMT, thereby avoiding extensive hemolysis and subsequent complications.

  6. Mechanical resistance of zirconium implant abutments: A review of the literature

    Science.gov (United States)

    Vaquero-Aguilar, Cristina; Torres-Lagares, Daniel; Jiménez-Melendo, Manuel; Gutiérrez-Pérez, José L.

    2012-01-01

    The increase of aesthetic demands, together with the successful outcome of current implants, has renewed interest in the search for new materials with enough mechanical properties and better aesthetic qualities than the materials customarily used in implanto-prosthetic rehabilitation. Among these materials, zirconium has been used in different types of implants, including prosthetic abutments. The aim of the present review is to analyse current scientific evidence supporting the use of this material for the above mentioned purposes. We carried out the review of the literature published in the last ten years (2000 through 2010) of in vitro trials of dynamic and static loading of zirconium abutments found in the databases of Medline and Cochrane using the key words zirconium abutment, fracture resistance, fracture strength, cyclic loading. Although we have found a wide variability of values among the different studies, abutments show favourable clinical behaviour for the rehabilitation of single implants in the anterior area. Such variability may be explained by the difficulty to simulate daily mastication under in vitro conditions. The clinical evidence, as found in our study, does not recommend the use of implanto-prosthetic zirconium abutments in the molar area. Key words: Zirconium abutment, zirconium implant abutment, zirconia abutment, fracture resistance, fracture strength, cyclic loading. PMID:22143702

  7. Mechanical model development of rolling bearing-rotor systems: A review

    Science.gov (United States)

    Cao, Hongrui; Niu, Linkai; Xi, Songtao; Chen, Xuefeng

    2018-03-01

    The rolling bearing rotor (RBR) system is the kernel of many rotating machines, which affects the performance of the whole machine. Over the past decades, extensive research work has been carried out to investigate the dynamic behavior of RBR systems. However, to the best of the authors' knowledge, no comprehensive review on RBR modelling has been reported yet. To address this gap in the literature, this paper reviews and critically discusses the current progress of mechanical model development of RBR systems, and identifies future trends for research. Firstly, five kinds of rolling bearing models, i.e., the lumped-parameter model, the quasi-static model, the quasi-dynamic model, the dynamic model, and the finite element (FE) model are summarized. Then, the coupled modelling between bearing models and various rotor models including De Laval/Jeffcott rotor, rigid rotor, transfer matrix method (TMM) models and FE models are presented. Finally, the paper discusses the key challenges of previous works and provides new insights into understanding of RBR systems for their advanced future engineering applications.

  8. Vitamin D as an adjunctive therapy in asthma. Part 1: A review of potential mechanisms.

    Science.gov (United States)

    Kerley, Conor P; Elnazir, Basil; Faul, John; Cormican, Liam

    2015-06-01

    Vitamin D deficiency (VDD) is highly prevalent worldwide. The classical role for vitamin D is to regulate calcium absorption form the gastrointestinal tract and influence bone health. Recently vitamin D receptors and vitamin D metabolic enzymes have been discovered in numerous sites systemically supporting diverse extra-skeletal roles of vitamin D, for example in asthmatic disease. Further, VDD and asthma share several common risk factors including high latitude, winter season, industrialization, poor diet, obesity, and dark skin pigmentation. Vitamin D has been demonstrated to possess potent immunomodulatory effects, including effects on T cells and B cells as well as increasing production of antimicrobial peptides (e.g. cathelicidin). This immunomodulation may lead to asthma specific clinical benefits in terms of decreased bacterial/viral infections, altered airway smooth muscle-remodeling and -function as well as modulation of response to standard anti-asthma therapy (e.g. glucocorticoids and immunotherapy). Thus, vitamin D and its deficiency have a number of biological effects that are potentially important in altering the course of disease pathogenesis and severity in asthma. The purpose of this first of a two-part review is to review potential mechanisms whereby altering vitamin D status may influence asthmatic disease. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Vitamin D as an adjunctive therapy in asthma. Part 1: A review of potential mechanisms.

    LENUS (Irish Health Repository)

    Kerley, Conor P

    2015-02-27

    Vitamin D deficiency (VDD) is highly prevlalent worldwide. The classical role for vitamin D is to regulate calcium absorption form the gastrointestinal tract and influence bone health. Recently vitamin D receptors and vitamin D metabolic enzymes have been discovered in numerous sites systemically supporting diverse extra-skeletal roles of vitamin D, for example in asthmatic disease. Further, VDD and asthma share several common risk factors including high latitude, winter season, industrialization, poor diet, obesity, and dark skin pigmentation. Vitamin D has been demonstrated to possess potent immunomodulatory effects, including effects on T cells and B cells as well as increasing production of antimicrobial peptides (e.g. cathelicidin). This immunomodulation may lead to asthma specific clinical benefits in terms of decreased bacterial\\/viral infections, altered airway smooth muscle-remodeling and -function as well as modulation of response to standard anti-asthma therapy (e.g. glucocorticoids and immunotherapy). Thus, vitamin D and its deficiency have a number of biological effects that are potentially important in altering the course of disease pathogenesis and severity in asthma. The purpose of this first of a two-part review is to review potential mechanisms whereby altering vitamin D status may influence asthmatic disease.

  10. Ginger-Mechanism of action in chemotherapy-induced nausea and vomiting: A review.

    Science.gov (United States)

    Marx, Wolfgang; Ried, Karin; McCarthy, Alexandra L; Vitetta, Luis; Sali, Avni; McKavanagh, Daniel; Isenring, Liz

    2017-01-02

    Despite advances in antiemetic therapy, chemotherapy-induced nausea and vomiting (CINV) still poses a significant burden to patients undergoing chemotherapy. Nausea, in particular, is still highly prevalent in this population. Ginger has been traditionally used as a folk remedy for gastrointestinal complaints and has been suggested as a viable adjuvant treatment for nausea and vomiting in the cancer context. Substantial research has revealed ginger to possess properties that could exert multiple beneficial effects on chemotherapy patients who experience nausea and vomiting. Bioactive compounds within the rhizome of ginger, particularly the gingerol and shogaol class of compounds, interact with several pathways that are directly implicated in CINV in addition to pathways that could play secondary roles by exacerbating symptoms. These properties include 5-HT 3 , substance P, and acetylcholine receptor antagonism; antiinflammatory properties; and modulation of cellular redox signaling, vasopressin release, gastrointestinal motility, and gastric emptying rate. This review outlines these proposed mechanisms by discussing the results of clinical, in vitro, and animal studies both within the chemotherapy context and in other relevant fields. The evidence presented in this review indicates that ginger possesses multiple properties that could be beneficial in reducing CINV.

  11. A review of cutting mechanics and modeling techniques for biological materials.

    Science.gov (United States)

    Takabi, Behrouz; Tai, Bruce L

    2017-07-01

    This paper presents a comprehensive survey on the modeling of tissue cutting, including both soft tissue and bone cutting processes. In order to achieve higher accuracy in tissue cutting, as a critical process in surgical operations, the meticulous modeling of such processes is important in particular for surgical tool development and analysis. This review paper is focused on the mechanical concepts and modeling techniques utilized to simulate tissue cutting such as cutting forces and chip morphology. These models are presented in two major categories, namely soft tissue cutting and bone cutting. Fracture toughness is commonly used to describe tissue cutting while Johnson-Cook material model is often adopted for bone cutting in conjunction with finite element analysis (FEA). In each section, the most recent mathematical and computational models are summarized. The differences and similarities among these models, challenges, novel techniques, and recommendations for future work are discussed along with each section. This review is aimed to provide a broad and in-depth vision of the methods suitable for tissue and bone cutting simulations. Copyright © 2017 IPEM. Published by Elsevier Ltd. All rights reserved.

  12. Physical and mechanical properties of PLA, and their functions in widespread applications - A comprehensive review.

    Science.gov (United States)

    Farah, Shady; Anderson, Daniel G; Langer, Robert

    2016-12-15

    Poly(lactic acid) (PLA), so far, is the most extensively researched and utilized biodegradable aliphatic polyester in human history. Due to its merits, PLA is a leading biomaterial for numerous applications in medicine as well as in industry replacing conventional petrochemical-based polymers. The main purpose of this review is to elaborate the mechanical and physical properties that affect its stability, processability, degradation, PLA-other polymers immiscibility, aging and recyclability, and therefore its potential suitability to fulfill specific application requirements. This review also summarizes variations in these properties during PLA processing (i.e. thermal degradation and recyclability), biodegradation, packaging and sterilization, and aging (i.e. weathering and hygrothermal). In addition, we discuss up-to-date strategies for PLA properties improvements including components and plasticizer blending, nucleation agent addition, and PLA modifications and nanoformulations. Incorporating better understanding of the role of these properties with available improvement strategies is the key for successful utilization of PLA and its copolymers/composites/blends to maximize their fit with worldwide application needs. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Acinetobacter spp. Infections in Malaysia: A Review of Antimicrobial Resistance Trends, Mechanisms and Epidemiology.

    Science.gov (United States)

    Mohd Rani, Farahiyah; A Rahman, Nor Iza; Ismail, Salwani; Alattraqchi, Ahmed Ghazi; Cleary, David W; Clarke, Stuart C; Yeo, Chew Chieng

    2017-01-01

    Acinetobacter spp. are important nosocomial pathogens, in particular the Acinetobacter baumannii - calcoaceticus complex, which have become a global public health threat due to increasing resistance to carbapenems and almost all other antimicrobial compounds. High rates of resistance have been reported among countries in Southeast Asia, including Malaysia. In this review, we examine the antimicrobial resistance profiles of Acinetobacter spp. hospital isolates from Malaysia over a period of nearly three decades (1987-2016) with data obtained from various peer-reviewed publications as well as the Malaysian National Surveillance on Antibiotic Resistance (NSAR). NSAR data indicated that for most antimicrobial compounds, including carbapenems, the peak resistance rates were reached around 2008-2009 and thereafter, rates have remained fairly constant (e.g., 50-60% for carbapenems). Individual reports from various hospitals in Peninsular Malaysia do not always reflect the nationwide resistance rates and often showed higher rates of resistance. We also reviewed the epidemiology and mechanisms of resistance that have been investigated in Malaysian Acinetobacter spp. isolates, particularly carbapenem resistance and found that bla OXA-23 is the most prevalent acquired carbapenemase-encoding gene. From the very few published reports and whole genome sequences that are available, most of the Acinetobacter spp. isolates from Malaysia belonged to the Global Clone 2 (GC2) CC92 group with ST195 being the predominant sequence type. The quality of data and analysis in the national surveillance reports could be improved and more molecular epidemiology and genomics studies need to be carried out for further in-depth understanding of Malaysian Acinetobacter spp. isolates.

  14. Division of Scientific Equipment - Overview

    International Nuclear Information System (INIS)

    Halik, J.

    2002-01-01

    Full text: The Scientific Equipment Division consists of the Design Group and the Mechanical Workshop. The activity of the Division includes the following: * designs of devices and equipment for experiments in physics; their mechanical construction and assembly. In particular, these are vacuum chambers and installations for HV and UHV;* maintenance and upgrading of the existing installations and equipment in our Institute; * participation of our engineers and technicians in design works, equipment assembly and maintenance for experiments in foreign laboratories. The Design Group is equipped with PC-computers and AutoCAD graphic software (release 2000 and Mechanical Desktop 4.0) and an A0 plotter, which allow us to make drawings and 2- and 3-dimensional mechanical documentation to the world standards. The Mechanical Workshop offers a wide range of machining and treatment methods with satisfactory tolerances and surface quality. They include: * turning - cylindrical elements of a length up to 2000 mm and a diameter up to 400 mm, and also disc type elements of a diameter up to 600 mm and a length not exceeding 300 mm, * milling - elements of length up to 1000 mm and gear wheels of diameter up to 300 mm, * grinding - flat surfaces of dimensions up to 300 mm x 1000 mm and cylindrical elements of a diameter up to 200 mm and a length up to 800 mm, * drilling - holes of a diameter up to 50 mm, * welding - electrical and gas welding, including TIG vacuum-tight welding, * soft and hard soldering, * mechanical works including precision engineering, * plastics treatment - machining and polishing using diamond milling, modelling, lamination of various shapes and materials, including plexiglas, scintillators and light-guides, * painting - paint spraying with possibility of using furnace-fired drier of internal dimensions of 800 mm x 800 mm x 800 mm. Our workshop is equipped with the CNC milling machine which can be used for machining of work pieces up to 500 kg. The machine

  15. Effects and mechanisms of biochar-microbe interactions in soil improvement and pollution remediation: A review.

    Science.gov (United States)

    Zhu, Xiaomin; Chen, Baoliang; Zhu, Lizhong; Xing, Baoshan

    2017-08-01

    Biochars have attracted tremendous attention due to their effects on soil improvement; they enhance carbon storage, soil fertility and quality, and contaminant (organic and heavy metal) immobilization and transformation. These effects could be achieved by modifying soil microbial habitats and (or) directly influencing microbial metabolisms, which together induce changes in microbial activity and microbial community structures. This review links microbial responses, including microbial activity, community structures and soil enzyme activities, with changes in soil properties caused by biochars. In particular, we summarized possible mechanisms that are involved in the effects that biochar-microbe interactions have on soil carbon sequestration and pollution remediation. Special attention has been paid to biochar effects on the formation and protection of soil aggregates, biochar adsorption of contaminants, biochar-mediated transformation of soil contaminants by microorganisms, and biochar-facilitated electron transfer between microbial cells and contaminants and soil organic matter. Certain reactive organic compounds and heavy metals in biochar may induce toxicity to soil microorganisms. Adsorption and hydrolysis of signaling molecules by biochar interrupts microbial interspecific communications, potentially altering soil microbial community structures. Further research is urged to verify the proposed mechanisms involved in biochar-microbiota interactions for soil remediation and improvement. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Mechanisms of action underlying the anti-inflammatory and immunomodulatory effects of propolis: a brief review

    Directory of Open Access Journals (Sweden)

    Marcio A. R. Araujo

    2011-09-01

    Full Text Available Many biological properties have been attributed to various types of propolis, including anti-inflammatory, antimicrobial, antioxidant, antitumor, wound healing, and immunomodulatory activities. This article reviewed studies published that investigated the anti-inflammatory activity of propolis of different origins and/or its isolated components, focusing on the mechanisms of action underlying this activity and also addressing some aspects of immunomodulatory effects. The search was performed of the following databases: PubMed, Science Direct, HighWire Press, Scielo, Google Academics, Research Gate and ISI Web of Knowledgement. The anti-inflammatory activity was associated with propolis or compounds such as polyphenols (flavonoids, phenolic acids and their esters, terpenoids, steroids and amino acids. CAPE is the most studied compounds. The main mechanisms underlying the anti-inflammatory activity of propolis included the inhibition of cyclooxygenase and consequent inhibition of prostaglandin biosynthesis, free radical scavenging, inhibition of nitric oxide synthesis, reduction in the concentration of inflammatory cytokines and immunosuppressive activity. Propolis was found to exert an anti-inflammatory activity in vivo and in vitro models of acute and chronic inflammation and others studies, indicating its promising potential as anti-inflammatory agent of natural origin and as a source of chemical compounds for the development of new drugs.

  17. A review of safety-focused mechanical modeling of commercial lithium-ion batteries

    Science.gov (United States)

    Zhu, Juner; Wierzbicki, Tomasz; Li, Wei

    2018-02-01

    We are rapidly approaching an inflection point in the adoption of electric vehicles on the roads. All major automotive companies are having well-funded plans for mass market affordable branded EV product line models, which can open the floodgates. A rapid growth of battery energy density, accompanied by an aggressive progress of reduction of costs of lithium-ion batteries, brings safety concerns. While more energy stored in the battery pack of an EV translates to a longer range, the downside is that accidents will be more violent due to battery inevitable explosion. With today's technology, severe crashes involving intrusion into the battery pack will potentially result in a thermal runaway, fire, and explosion. Most of research on lithium-ion batteries have been concerned with the electrochemistry of cells. However, in most cases failure and thermal runaway is caused by mechanical loading due to crash events. There is a growing need to summarize the already published results on mechanical loading and response of batteries and offer a critical evaluation of work in progress. The objective of this paper is to present such review with a discussion of many outstanding issues and outline of a roadmap for future research.

  18. The mechanisms of heavy metal immobilization by cementitious material treatments and thermal treatments: A review.

    Science.gov (United States)

    Guo, Bin; Liu, Bo; Yang, Jian; Zhang, Shengen

    2017-05-15

    Safe disposal of solid wastes containing heavy metals is a significant task for environment protection. Immobilization treatment is an effective technology to achieve this task. Cementitious material treatments and thermal treatments are two types of attractive immobilization treatments due to that the heavy metals could be encapsulated in their dense and durable wasteforms. This paper discusses the heavy metal immobilization mechanisms of these methods in detail. Physical encapsulation and chemical stabilization are two fundamental mechanisms that occur simultaneously during the immobilization processes. After immobilization treatments, the wasteforms build up a low permeable barrier for the contaminations. This reduces the exposed surface of wastes. Chemical stabilization occurs when the heavy metals transform into more stable and less soluble metal bearing phases. The heavy metal bearing phases in the wasteforms are also reviewed in this paper. If the heavy metals are incorporated into more stable and less soluble metal bearing phases, the potential hazards of heavy metals will be lower. Thus, converting heavy metals into more stable phases during immobilization processes should be a common way to enhance the immobilization effect of these immobilization methods. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. A review of mechanisms of circumvention and modulation of chemotherapeutic drug resistance.

    Science.gov (United States)

    O'Connor, R

    2009-05-01

    Drug resistance is a serious limitation to the effective treatment of a number of common malignancies. Thirty years of laboratory and clinical research have greatly defined the molecular alterations underlying many drug resistance processes in cancer. Based on this knowledge, strategies to overcome the impact of resistance and increase the efficacy of cancer treatment have been translated from laboratory models to clinical trials. This article reviews laboratory and, in particular, clinical attempts at drug resistance circumvention from early forays in the inhibition of cellular efflux pump-mediated drug resistance through to more selective circumvention agent strategies and into inhibition of the other important mechanisms which can allow cancer cells to survive therapy, such as apoptosis resistance. Despite some promising results to date, resistance inhibition strategies have largely failed due to poor understanding of the pharmacology, dynamics and complexity of the resistance phenotype. With the realisation that new molecularly-targeted agents can also be rendered ineffectual by the actions of resistance mechanisms, a major focus is once again emerging on identifying new strategies/pharmaceuticals which can augment the activity of the arsenal of more conventional cytotoxics and newer targeted anti-cancer drugs. Future tactical directions where old and new resistance strategies may merge to overcome this challenge are discussed.

  20. Translating Mechanism-Based Strategies to Break the Obesity-Cancer Link: A Narrative Review.

    Science.gov (United States)

    Smith, Laura A; O'Flanagan, Ciara H; Bowers, Laura W; Allott, Emma H; Hursting, Stephen D

    2018-04-01

    Prevalence of obesity, an established risk factor for many cancers, has increased dramatically over the past 50 years in the United States and across the globe. Relative to normoweight cancer patients, obese cancer patients often have poorer prognoses, resistance to chemotherapies, and are more likely to develop distant metastases. Recent progress on elucidating the mechanisms underlying the obesity-cancer connection suggests that obesity exerts pleomorphic effects on pathways related to tumor development and progression and, thus, there are multiple opportunities for primary prevention and treatment of obesity-related cancers. Obesity-associated alterations, including systemic metabolism, adipose inflammation, growth factor signaling, and angiogenesis, are emerging as primary drivers of obesity-associated cancer development and progression. These obesity-associated host factors interact with the intrinsic molecular characteristics of cancer cells, facilitating several of the hallmarks of cancer. Each is considered in the context of potential preventive and therapeutic strategies to reduce the burden of obesity-related cancers. In addition, this review focuses on emerging mechanisms behind the obesity-cancer link, as well as relevant dietary interventions, including calorie restriction, intermittent fasting, low-fat diet, and ketogenic diet, that are being implemented in preclinical and clinical trials, with the ultimate goal of reducing incidence and progression of obesity-related cancers. Copyright © 2018 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

  1. Capability and Mechanisms of Macrofungi in Heavy Metal Accumulation:A Review

    Directory of Open Access Journals (Sweden)

    CHEN Miao-miao

    2017-10-01

    Full Text Available Some macrofungi have the ability to accumulate heavy metals, which is comparable to hyper-accumulator plants. Cordyceps militaris can accumulate Zn up to 20 000 mg·kg-1. Therefore, macrofungi have the potential to be used as an important bioremediation tool for heavy metals. In this review, we summarized the heavy metal resistant capacity of typical macrofungi and known relevant mechanisms. Generally, straw-decay fungi presented better capability for Cu, Ag and Cd enrichment than wood-decay fungi, while wood-decay fungi could accumulate Cr, Mg, Se and Pb. Different macrofungi species, different growth periods(mycelium and fruiting body and different parts of fruiting body showed different capability for heavy metals accumulation. General mechanisms for heavy metals accumulation in macrofungi included extracellular precipitation in the forms of polymeric substances, cell wall adsorption and intracellular absorption. Macrofungi could also detoxify by chelating metal ions by metallothionein(MT, secreting antioxidant enzymes(SOD, CAT, POD and degradating the misfolded proteins by ubiquitin-proteasome system(UPS. We also explored the potential of macrofungi in heavy metal remediation and pollution diagnostics as a biological indicator. Some macrofungi had been applied in the remediation of heavy metal contaminated soils and water. Finally, some future research areas including strain breeding and genetic engineering were discussed, which might provide references for the future studies.

  2. Sirenomelia of an intracytoplasmic sperm injection conceptus: a case report and review of mechanism.

    Science.gov (United States)

    Bakhtar, Omid; Benirschke, Kurt; Masliah, Eliezer

    2006-01-01

    Postmortem dissection of the 18-week male conceptus, product of intracytoplasmic sperm injection (ICSI), demonstrated the hallmark findings of sirenomelia. The lower legs were fused and the left knee was rotated medially. Internal organs showed hypoplastic lungs, a multicystic kidney, and unilateral ureteral hypoplasia. The vitelline artery was absorbed, in a classic fashion, into the umbilical artery and communicated with the aorta at a point proximal to the iliac arteries. The tributaries distal to this point were hypoplastic. This finding is consistent with previously documented cases of sirenomelia and is thought to be the pathogenetic mechanism resulting in a vascular steal from the lower extremities. A rare finding was the presence of a penis on the dorsal side just below a perforate anus. In this case report, we discuss the pertinent clinical history and autopsy findings. A brief review of the mechanism thought to give rise to sirenomelia is provided. To our knowledge, this is the first reported case of sirenomelia in an ICSI conceptus.

  3. Review on mechanisms of dairy summer infertility and implications for hormonal intervention

    Directory of Open Access Journals (Sweden)

    B.U. Wakayo

    2015-02-01

    Full Text Available In dairy cows and buffaloes, summer heat stress (HS reduces milk yield and delays return to pregnancy leading to financial loss. Clues for effective interventions against summer infertility (SI lie in understanding the underlying mechanisms. This article reviews current knowledge on the mechanisms of bovine SI and their implication for hormonal management. Under HS dairy animals encounter anestrous, silent cycles and repeat breeding which extend their open period. These effects are attributed mainly to HS induced disturbances in luteinizing hormone (LH secretion, follicular dominance and estrogen secretion, ovulation and oocyte competence, luteal development and progesterone secretion, utero-placental function and embryo-fetal development. Hormonal timed artificial insemination protocols and LH support around estrous improved summer pregnancy rates by avoiding need for estrus detection, assisting follicular development and ovulation, enhancing quality oocytes and stimulating luteal function. Progesterone supplementation to enhance embryonic development did not produce significant improvement in summer pregnancy rates. There is need for evaluating integrated approaches combining hormones, metabolic modifier and cyto-protective agents.

  4. Mechanisms Underlying Cytotoxicity Induced by Engineered Nanomaterials: A Review of In Vitro Studies

    Science.gov (United States)

    Nogueira, Daniele R.; Mitjans, Montserrat; Rolim, Clarice M. B.; Vinardell, M. Pilar

    2014-01-01

    Engineered nanomaterials are emerging functional materials with technologically interesting properties and a wide range of promising applications, such as drug delivery devices, medical imaging and diagnostics, and various other industrial products. However, concerns have been expressed about the risks of such materials and whether they can cause adverse effects. Studies of the potential hazards of nanomaterials have been widely performed using cell models and a range of in vitro approaches. In the present review, we provide a comprehensive and critical literature overview on current in vitro toxicity test methods that have been applied to determine the mechanisms underlying the cytotoxic effects induced by the nanostructures. The small size, surface charge, hydrophobicity and high adsorption capacity of nanomaterial allow for specific interactions within cell membrane and subcellular organelles, which in turn could lead to cytotoxicity through a range of different mechanisms. Finally, aggregating the given information on the relationships of nanomaterial cytotoxic responses with an understanding of its structure and physicochemical properties may promote the design of biologically safe nanostructures. PMID:28344232

  5. A review of visual perception mechanisms that regulate rapid adaptive camouflage in cuttlefish.

    Science.gov (United States)

    Chiao, Chuan-Chin; Chubb, Charles; Hanlon, Roger T

    2015-09-01

    We review recent research on the visual mechanisms of rapid adaptive camouflage in cuttlefish. These neurophysiologically complex marine invertebrates can camouflage themselves against almost any background, yet their ability to quickly (0.5-2 s) alter their body patterns on different visual backgrounds poses a vexing challenge: how to pick the correct body pattern amongst their repertoire. The ability of cuttlefish to change appropriately requires a visual system that can rapidly assess complex visual scenes and produce the motor responses-the neurally controlled body patterns-that achieve camouflage. Using specifically designed visual backgrounds and assessing the corresponding body patterns quantitatively, we and others have uncovered several aspects of scene variation that are important in regulating cuttlefish patterning responses. These include spatial scale of background pattern, background intensity, background contrast, object edge properties, object contrast polarity, object depth, and the presence of 3D objects. Moreover, arm postures and skin papillae are also regulated visually for additional aspects of concealment. By integrating these visual cues, cuttlefish are able to rapidly select appropriate body patterns for concealment throughout diverse natural environments. This sensorimotor approach of studying cuttlefish camouflage thus provides unique insights into the mechanisms of visual perception in an invertebrate image-forming eye.

  6. A review of penetration mechanisms and dynamic properties of tungsten and depleted uranium penetrators

    International Nuclear Information System (INIS)

    Andrew, S.P.; Caligiuri, R.D.; Eiselstein, L.E.

    1991-01-01

    Kinetic energy penetrators must posses the best possible combination of hardness, stiffness, strength, and fracture toughness characteristics to be effective against modern armor systems. Over the last decade, depleted uranium (DU) and tungsten alloys have been the materials of choice for kinetic energy penetrators. Du and tungsten perform abut the same against semi-infinite targets, and DU outperforms tungsten penetrators in oblique, spaced array targets, but because of environmental and subsequent cost concerns, effort has focused on improving the performance of tungsten penetrators over the last few years. However, despite recent improvements in material properties, the penetration performance of tungsten still lags behind that of DU. One possible reason is the difference in deformation mechanisms at the leading edge of the penetrator during the penetration process-DU alloys tend to shear band and sharpen as they penetrate the target material, whereas tungsten penetrators tend to mushroom and blunt. As a first step to determine whether shear banding is truly the reason for superior DU performance, a review of the fabrication, high strain-rate properties, and penetration phenomena of penetrators manufactured from both tungsten and DU alloys. Specifically, the effects of composition, processing, and heat treatment on material properties and penetration mechanisms of these alloys are discussed

  7. Big data handling mechanisms in the healthcare applications: A comprehensive and systematic literature review.

    Science.gov (United States)

    Pashazadeh, Asma; Jafari Navimipour, Nima

    2018-04-12

    Healthcare provides many services such as diagnosing, treatment, prevention of diseases, illnesses, injuries, and other physical and mental disorders. Large-scale distributed data processing applications in healthcare as a basic concept operates on large amounts of data. Therefore, big data application functions are the main part of healthcare operations, but there was not any comprehensive and systematic survey about studying and evaluating the important techniques in this field. Therefore, this paper aims at providing the comprehensive, detailed, and systematic study of the state-of-the-art mechanisms in the big data related to healthcare applications in five categories, including machine learning, cloud-based, heuristic-based, agent-based, and hybrid mechanisms. Also, this paper displayed a systematic literature review (SLR) of the big data applications in the healthcare literature up to the end of 2016. Initially, 205 papers were identified, but a paper selection process reduced the number of papers to 29 important studies. Copyright © 2018 Elsevier Inc. All rights reserved.

  8. A review of potential neurotoxic mechanisms among three chlorinated organic solvents

    International Nuclear Information System (INIS)

    Bale, Ambuja S.; Barone, Stan; Scott, Cheryl Siegel; Cooper, Glinda S.

    2011-01-01

    The potential for central nervous system depressant effects from three widely used chlorinated solvents, trichloroethylene (TCE), perchloroethylene (PERC), and dichloromethane (DCM), has been shown in human and animal studies. Commonalities of neurobehavioral and neurophysiological changes for the chlorinated solvents in in vivo studies suggest that there is a common mechanism(s) of action in producing resultant neurotoxicological consequences. The purpose of this review is to examine the mechanistic studies conducted with these chlorinated solvents and to propose potential mechanisms of action for the different neurological effects observed. Mechanistic studies indicate that this solvent class has several molecular targets in the brain. Additionally, there are several pieces of evidence from animal studies indicating this solvent class alters neurochemical functions in the brain. Although earlier evidence indicated that these three chlorinated solvents perturb the lipid bilayer, more recent data suggest an interaction between several specific neuronal receptors produces the resultant neurobehavioral effects. Collectively, TCE, PERC, and DCM have been reported to interact directly with several different classes of neuronal receptors by generally inhibiting excitatory receptors/channels and potentiating the function of inhibitory receptors/channels. Given this mechanistic information and available studies for TCE, DCM, and PERC, we provide hypotheses on primary targets (e.g. ion channel targets) that appear to be most influential in producing the resultant neurological effects. - Research highlights: → Comparison of neurological effects among TCE, PERC, and DCM. → Correlation of mechanistic findings to neurological effects. → Data support that TCE, PERC, and DCM interact with several ion channels to produce neurological changes.

  9. Mechanical properties of crossed-lamellar structures in biological shells: A review.

    Science.gov (United States)

    Li, X W; Ji, H M; Yang, W; Zhang, G P; Chen, D L

    2017-10-01

    The self-fabrication of materials in nature offers an alternate and powerful solution towards the grand challenge of designing advanced structural materials, where strength and toughness are always mutually exclusive. Crossed-lamellar structures are the most common microstructures in mollusks that are composed of aragonites and a small amount of organic materials. Such a distinctive composite structure has a fracture toughness being much higher than that of pure carbonate mineral. These structures exhibiting complex hierarchical microarchitectures that span several sub-level lamellae from microscale down to nanoscale, can be grouped into two types, i.e., platelet-like and fiber-like crossed-lamellar structures based on the shapes of basic building blocks. It has been demonstrated that these structures have a great potential to strengthen themselves during deformation. The observed underlying toughening mechanisms include microcracking, channel cracking, interlocking, uncracked-ligament bridging, aragonite fiber bridging, crack deflection and zig-zag, etc., which play vital roles in enhancing the fracture resistance of shells with the crossed-lamellar structures. The exploration and utilization of these important toughening mechanisms have attracted keen interests of materials scientists since they pave the way for the development of bio-inspired advanced composite materials for load-bearing structural applications. This article is aimed to review the characteristics of hierarchical structures and the mechanical properties of two kinds of crossed-lamellar structures, and further summarize the latest advances and biomimetic applications based on the unique crossed-lamellar structures. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Structural, mechanical and chemical evaluation of molar-incisor hypomineralization-affected enamel: A systematic review.

    Science.gov (United States)

    Elhennawy, Karim; Manton, David John; Crombie, Felicity; Zaslansky, Paul; Radlanski, Ralf J; Jost-Brinkmann, Paul-Georg; Schwendicke, Falk

    2017-11-01

    To systematically assess and contrast reported differences in microstructure, mineral density, mechanical and chemical properties between molar-incisor-hypomineralization-affected (MIH) enamel and unaffected enamel. Studies on extracted human teeth, clinically diagnosed with MIH, reporting on the microstructure, mechanical properties or the chemical composition and comparing them to unaffected enamel were reviewed. Electronic databases (PubMed, Embase and Google Scholar) were screened; hand searches and cross-referencing were also performed. Twenty-two studies were included. Fifteen studies on a total of 201 teeth investigated the structural properties, including ten (141 teeth) on microstructure and seven (60 teeth) on mineral density; six (29 teeth) investigated the mechanical properties and eleven (87 teeth) investigated the chemical properties of MIH-affected enamel and compared them to unaffected enamel. Studies unambiguously found a reduction in mineral quantity and quality (reduced Ca and P content), reduction of hardness and modulus of elasticity (also in the clinically sound-appearing enamel bordering the MIH-lesion), an increase in porosity, carbon/carbonate concentrations and protein content compared to unaffected enamel. were ambiguous with regard to the extent of the lesion through the enamel to the enamel-dentin junction, the Ca/P ratio and the association between clinical appearance and defect severity. There is an understanding of the changes related to MIH-affected enamel. The association of these changes with the clinical appearance and resulting implications for clinical management are unclear. MIH-affected enamel is greatly different from unaffected enamel. This has implications for management strategies. The possibility of correlating the clinical appearance of MIH-affected enamel with the severity of enamel changes and deducing clinical concepts (risk stratification etc.) is limited. Crown Copyright © 2017. Published by Elsevier Ltd. All

  11. Mechanisms of action of brief alcohol interventions remain largely unknown – A narrative review

    Directory of Open Access Journals (Sweden)

    Jacques eGaume

    2014-08-01

    Full Text Available A growing body of evidence has shown efficacy of brief intervention (BI for hazardous and harmful alcohol use in primary health care settings. Evidence for efficacy in other settings, and effectiveness when implemented at larger scale is disappointing. Indeed, BI comprises varying content, and exploring BI content and mechanisms of action may be a promising way to enhance efficacy and effectiveness.We searched Medline and PsychInfo, as well as references of retrieved publications for original research or reviews on active ingredients (or components, or mechanisms of face-to-face BIs (and its subtypes, including brief advice and brief motivational interviewing [BMI] for alcohol. Overall, BI active ingredients have been scarcely investigated, almost only within BMI, and mostly among Emergency Room patients, young adults, and US college students. This body of research has shown that personalized feedback may be an effective component; specific MI techniques showed mixed findings; decisional balance findings tended to suggest a potential detrimental effect; while change plan exercises, advice to reduce or stop drinking, presenting alternative change options, and moderation strategies are promising but need further study. Client change talk is a potential mediator of BMI effects; change in norm perceptions and enhanced discrepancy between current behavior and broader life goals and values have received preliminary support; readiness to change was only partially supported as a mediator; while enhanced awareness of drinking, perceived risks/benefits of alcohol use, alcohol treatment seeking, and self-efficacy were seldom studied and have as yet found no significant support as such.Research is obviously limited and has provided no clear and consistent evidence on the mechanisms of alcohol BI. How BI achieves the effects seen in randomized trials remains mostly unknown and should be investigated to inform the development of more effective interventions.

  12. Mechanisms of action of brief alcohol interventions remain largely unknown - a narrative review.

    Science.gov (United States)

    Gaume, Jacques; McCambridge, Jim; Bertholet, Nicolas; Daeppen, Jean-Bernard

    2014-01-01

    A growing body of evidence has shown the efficacy of brief intervention (BI) for hazardous and harmful alcohol use in primary health care settings. Evidence for efficacy in other settings and effectiveness when implemented at larger scale are disappointing. Indeed, BI comprises varying content; exploring BI content and mechanisms of action may be a promising way to enhance efficacy and effectiveness. Medline and PsychInfo, as well as references of retrieved publications were searched for original research or review on active ingredients (components or mechanisms) of face-to-face BIs [and its subtypes, including brief advice and brief motivational interviewing (BMI)] for alcohol. Overall, BI active ingredients have been scarcely investigated, almost only within BMI, and mostly among patients in the emergency room, young adults, and US college students. This body of research has shown that personalized feedback may be an effective component; specific MI techniques showed mixed findings; decisional balance findings tended to suggest a potential detrimental effect; while change plan exercises, advice to reduce or stop drinking, presenting alternative change options, and moderation strategies are promising but need further study. Client change talk is a potential mediator of BMI effects; change in norm perceptions and enhanced discrepancy between current behavior and broader life goals and values have received preliminary support; readiness to change was only partially supported as a mediator; while enhanced awareness of drinking, perceived risks/benefits of alcohol use, alcohol treatment seeking, and self-efficacy were seldom studied and have as yet found no significant support as such. Research is obviously limited and has provided no clear and consistent evidence on the mechanisms of alcohol BI. How BI achieves the effects seen in randomized trials remains mostly unknown and should be investigated to inform the development of more effective interventions.

  13. Parent-related mechanisms underlying the social gradient of childhood overweight and obesity: a systematic review.

    Science.gov (United States)

    Mech, P; Hooley, M; Skouteris, H; Williams, J

    2016-09-01

    Low socio-economic status (SES) is a significant risk factor for childhood overweight and obesity (COWOB) in high-income countries. Parents to young children buffer and accentuate social and cultural influences, and are central to the development of this disease. An understanding of the parent-related mechanisms that underlie the SES-COWOB relationship is needed to improve the efficacy of prevention and intervention efforts. A systematic review of relevant literature was conducted to investigate the mechanisms by which levels of SES (low, middle and high) are associated to COWOB, by exploring mediation and interaction effects. Six electronic databases were searched yielding 5155 initial records, once duplicates were removed. Studies were included if they investigated COWOB, SES, parent-related factors and the multivariate relationship between these factors. Thirty studies were included. Factors found to be mediating the SES-COWOB relationship or interacting with SES to influence COWOB were categorized according to an ecological systems framework, at child, parent, household and social system level factors. High parent body mass index, ethnicity, child-care attendance, high TV time (mother and child), breastfeeding (early weaning), food intake behaviours and birthweight potentially mediate the relationship between SES and COWOB. Different risk factors for COWOB in different SES groups were found. For low SES families, parental obesity and maternal depressive symptoms were strong risk factors for COWOB, whereas long maternal working hours and a permissive parenting style were risk factors for higher SES families. None of the studies investigated parental psychological attributes such as attitudes, beliefs, self-esteem and so on as potential mechanisms/risk factors. Families from different SES groups have different risk and protective factors for COWOB. Prevention and intervention efforts may have improved efficacy if they are tailored to address specific risk factors

  14. Clinical decision - making review on magnetic attachments versus mechanical attachments in dental prosthetics

    Directory of Open Access Journals (Sweden)

    Francesca Fabiano

    2017-11-01

    Full Text Available Background Conventional dentures in edentulous patients show some limitations due to the lack of retention, support and stability thus resulting in difficulty to chew. The modern implantology allows to use different implant overdentures and different attachment systems. The selection of the attachment by practitioners is mainly influenced by the clinical experience or technical preferences. Aims The aim of the present review is to provide an adequate background to the clinicians, in order to select the prosthetic attachments according to the current literature. The mechanical attachments have been compared to the magnetic devices, with the aim to guide the decision of the practitioners. Methods Articles topics selection was based on the use of magnetic attachments in dentistry and the comparison between them and mechanical connectors. The databases used were PubMed/MEDLINE, Google Scholar and ISI Web of Science. A critical evaluation of the selected paper has been made to choose the ones that matched the inclusion criteria. Results Nowadays, few studies have compared different attachments in a manner useful for clinical decision-making. The main problem limiting long-term durability of magnetic attachments in the oral fluid is the poor corrosion resistance of permanent magnets and the consequent leaching of cytotoxic ions. Conclusion Magnetic attachments in comparison with other attaching systems can be useful in patients with special needs, in patients with limited interocclusal space, or in patients with neuromuscular limitations, thanks to the automatic reseating properties. However, it’s important to highlight that the mechanical attachments still represent the best choice in common conditions requiring dental prostheses.

  15. 46 CFR 133.45 - Tests and inspections of lifesaving equipment and arrangements.

    Science.gov (United States)

    2010-10-01

    ... of flotation equipment such as lifebuoys, lifejackets, immersion suits, work vests, lifefloats... mechanisms; (3) The proper condition of flotation equipment such as lifebuoys, lifejackets, immersion suits, work vests, lifefloats, buoyant apparatus, and associated equipment; (4) That each inflatable liferaft...

  16. Black silicon method X: a review on high speed and selective plasma etching of silicon with profile control: an in-depth comparison between Bosch and cryostat DRIE processes as a roadmap to next generation equipment

    International Nuclear Information System (INIS)

    Jansen, H V; De Boer, M J; Unnikrishnan, S; Louwerse, M C; Elwenspoek, M C

    2009-01-01

    silicon loading) and ionic impact (due to metallic masks and/or exposed silicon) are the main sources of heat that might raise the wafer temperature uncontrollably, and they show the weakness of the helium backside technique using mechanical clamping. Electrostatic clamping, an alternative technique, should minimize this problem because it is less susceptible to heat transfer when its thermal resistance and the gap of the helium backside cavity are minimized; however, it is not a subject of the current study. Because oxygen-growth-based etch processes (due to their ultra thin inhibiting layer) rely more heavily on a constant wafer temperature than fluorocarbon-based processes, oxygen etches are more affected by temperature fluctuations and drifts during the etching. The fourth outcome of this review is a phenomenological model, which explains and predicts many features with respect to loading, flow and pressure behaviour in DRIE equipment including a diffusion zone. The model is a reshape of the flow model constructed by Mogab, who studied the loading effect in plasma etching. Despite the downside of needing a cryostat, it is shown that—when selecting proper conditions—a cryogenic two-step pulsed mode can be used as a successful technique to achieve high speed and selective plasma etching with an etch rate around 25 µm min −1 ( −1 at an efficiency of 33% for the fluorine generation from the SF 6 feed gas) by minimizing the time the free radicals need to pass the diffusion zone. It is anticipated that this residence time can be reduced sufficiently by a proper inductive coupled plasma (ICP) source design (e.g. plasma shower head and concentrator). In order to preserve the correct profile at such high etch rates, the pressure during the bottom removal step should be minimized and, therefore, the synchronized three-step pulsed mode is believed to be essential to reach such high etch rates with sufficient profile control. In order to improve the etch rate even

  17. Practice patterns and outcomes associated with early sedation depth in mechanically ventilated patients: a systematic review protocol.

    Science.gov (United States)

    Stephens, Robert J; Dettmer, Matthew R; Roberts, Brian W; Fowler, Susan A; Fuller, Brian M

    2017-06-09

    Mechanical ventilation is a commonly performed intervention in critically ill patients. Frequently, these patients experience deep sedation early in their clinical course. Emerging data suggest that the practice of early deep sedation may negatively impact patient outcomes. The purpose of this review is to assess the world's literature to describe and determine the impact of early deep sedation on the outcomes of mechanically ventilated patients. Randomised controlled trials and non-randomised studies will be eligible for inclusion in this systematic review. With the assistance of a medical librarian, we will comprehensively search MEDLINE, Embase, Scopus, Cochrane Central Register of Controlled Trials, Database of Abstracts of Reviews and Effects, and Cochrane Database of Systematic Reviews for peer-reviewed literature. Grey literature from appropriate professional society conferences, held from 2010 to 2017, will be reviewed manually. Two authors will independently review all search results, and disagreements will be resolved through arbitration by a third author. If appropriate, meta-analysis will be used for quantitative analysis of the data. Heterogeneity between studies will be assessed using the I 2 statistic. The proposed systematic review will not collect data that are associated with individual patients and does not require ethical approval. Results of this study will contribute to the understanding of early sedation, identify future research targets and guide early care in mechanically ventilated patients. This systematic review has been registered in the international prospective register of systematic reviews (PROSPERO #CRD42017057264). © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  18. Regulatory process for material handling equipment

    International Nuclear Information System (INIS)

    Rajendran, S.; Agarwal, Kailash

    2017-01-01

    Atomic Energy (Factories) Rules (AEFR) 1996, Rule 35 states, 'Thorough inspection and load testing of a Crane shall be done by a Competent Person at least once every 12 months'. To adhere to this rule, BARC Safety Council constituted 'Material Handling Equipment Committee (MHEC)' under the aegis of Conventional Fire and Safety Review Committee (CFSRC) to carry out periodical inspection and certification of Material Handling Equipment (MHE), tools and tackles used in BARC Facilities at Trombay, Tarapur and Kalpakkam

  19. Development of a telerobotic system for handling contaminated process equipment

    International Nuclear Information System (INIS)

    Fisher, J.J.; Ward, C.R.; Schuler, T.F.

    1987-01-01

    E. I. du Pont de Nemours and Company is evaluating a unique eight-degree-of-freedom Telerobot manipulator to perform size-reduction and material handling operations on contaminated process equipment at the Savannah River Plant (SRP). The Telerobot will be installed in the proposed Transuranic (TRU) Waste Processing Facility, which is scheduled to be operational by 1990. A full-scale prototype Telerobot, manufactured by GCA Corporation, St. Paul, MN is being tested with other process equipment in the Components Test Facility at the Savannah River Laboratory (SRL). All telerobotic operations required in the TRU Waste Facility such as crate unpacking, equipment dismantling, material size-reduction, and selected maintenance operations are being tested. This paper discusses the major mechanical and control features of the Telerobot system. Several system enhancements were added by SRL, including a new quick-hand-change coupling and expanded software control functions. The new software enables a system operator to perform both teleoperated and automatic tasks through several operating modes. These enhancements, as well as future mechanical, control system, and software features, are reviewed

  20. Vitamins in Pancreatic Cancer: A Review of Underlying Mechanisms and Future Applications12

    Science.gov (United States)

    Davis-Yadley, Ashley H; Malafa, Mokenge P

    2015-01-01

    Although there is increasing evidence that vitamins influence pancreatic adenocarcinoma biology and carcinogenesis, a comprehensive review is lacking. In this study, we performed a PubMed literature search to review the anticancer mechanisms and the preclinical and clinical studies that support the development of the bioactive vitamins A, C, D, E, and K in pancreatic cancer intervention. Preclinical studies have shown promising results for vitamin A in pancreatic cancer prevention, with clinical trials showing intriguing responses in combination with immunotherapy. For vitamin C, preclinical studies have shown slower tumor growth rates and/or increased survival when used alone or in combination with gemcitabine, with clinical trials with this combination revealing decreased primary tumor sizes and improved performance status. Preclinical studies with vitamin D analogues have shown potent antiproliferative effects and repression of migration and invasion of pancreatic cancer cells, with a clinical trial showing increased time to progression when calciferol was added to docetaxel. For vitamin E, preclinical studies have shown that δ-tocotrienol and γ-tocotrienol inhibited tumor cell growth and survival and augmented gemcitabine activity. Early-phase clinical trials with δ-tocotrienol are ongoing. Vitamin K demonstrates activation of apoptosis and inhibition of cellular growth in pancreatic tumor cells; however, there are no clinical studies available for further evaluation. Although preclinical and clinical studies are encouraging, randomized controlled trials with endpoints based on insights gained from mechanistic and preclinical studies and early-phase clinical trials are required to determine the efficacy of bioactive vitamin interventions in pancreatic cancer. PMID:26567201

  1. A systematic review on potential mechanisms of minocycline in kidney diseases.

    Science.gov (United States)

    Haghi-Aminjan, Hamed; Asghari, Mohammad Hossein; Goharbari, Mohammad Hadi; Abdollahi, Mohammad

    2017-08-01

    Kidney diseases need specialized health care and still are a reason of death. There is a large body of evidence that indicates minocycline possesses some cytoprotective effects beside of antibacterial properties. In this review, we aimed to explain cytoprotective mechanisms and kidney protection of minocycline. In order to find the effects of minocycline on kidney diseases a systematic literature search was performed, according to the guidelines proposed at the PRISMA statement in the electronic databases, including: PubMed, Scopus, and Web of Science up to August 2016, using the term 'minocycline' combined either by 'kidney' or 'renal' and published in English language. The following criteria were included: (1) studies that used minocycline in renal diseases; (2) full-text articles; (3) English language; (4) no limitation in publications with in-vivo or in-vitro and human or animal subjects. Our search provided a total of 1056 articles which 1045 of them were discarded due to not meeting the inclusion criteria. It has been clear that several factors, including apoptosis, oxidative stress, mitochondrial dysfunction and inflammation have pivotal roles in the development and progression of kidney diseases. Minocycline protective properties are via several ways, including anti-apoptotic, free radical scavenging, anti-inflammatory, effect on mitochondrial functions and inhibition of matrix metalloproteinase. This systematic review confirmed that minocycline could have significant effects on treatment of renal malfunctions. However, regarding any possible adverse effects of antibiotics, it appears that more investigation is still needed in this context. Copyright © 2017 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  2. Stress, burnout and depression: A systematic review on DNA methylation mechanisms.

    Science.gov (United States)

    Bakusic, Jelena; Schaufeli, Wilmar; Claes, Stephan; Godderis, Lode

    2017-01-01

    Despite that burnout presents a serious burden for modern society, there are no diagnostic criteria. Additional difficulty is the differential diagnosis with depression. Consequently, there is a need to dispose of a burnout biomarker. Epigenetic studies suggest that DNA methylation is a possible mediator linking individual response to stress and psychopathology and could be considered as a potential biomarker of stress-related mental disorders. Thus, the aim of this review is to provide an overview of DNA methylation mechanisms in stress, burnout and depression. In addition to state-of-the-art overview, the goal of this review is to provide a scientific base for burnout biomarker research. We performed a systematic literature search and identified 25 pertinent articles. Among these, 15 focused on depression, 7 on chronic stress and only 3 on work stress/burnout. Three epigenome-wide studies were identified and the majority of studies used the candidate-gene approach, assessing 12 different genes. The glucocorticoid receptor gene (NR3C1) displayed different methylation patterns in chronic stress and depression. The serotonin transporter gene (SLC6A4) methylation was similarly affected in stress, depression and burnout. Work-related stress and depressive symptoms were associated with different methylation patterns of the brain derived neurotrophic factor gene (BDNF) in the same human sample. The tyrosine hydroxylase (TH) methylation was correlated with work stress in a single study. Additional, thoroughly designed longitudinal studies are necessary for revealing the cause-effect relationship of work stress, epigenetics and burnout, including its overlap with depression. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. HVAC systems and equipment

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, S.T. (Linford Air and Refrigeration Company, Oakland, CA (US))

    1990-02-01

    The author discusses the section of the ASHRAE Standard 90.1-1989 which addresses HVAC systems and equipment. New features of HVAC systems mandatory general requirements are described. New prescriptive requirements are detailed.

  4. Personal Protective Equipment

    National Research Council Canada - National Science Library

    1998-01-01

    ... of personal protective equipment A safety program for new employees is a necessary part of any orientation program An on-going safety program should be used to motivate employees to continue to use...

  5. Electronic equipment packaging technology

    CERN Document Server

    Ginsberg, Gerald L

    1992-01-01

    The last twenty years have seen major advances in the electronics industry. Perhaps the most significant aspect of these advances has been the significant role that electronic equipment plays in almost all product markets. Even though electronic equipment is used in a broad base of applications, many future applications have yet to be conceived. This versatility of electron­ ics has been brought about primarily by the significant advances that have been made in integrated circuit technology. The electronic product user is rarely aware of the integrated circuits within the equipment. However, the user is often very aware of the size, weight, mod­ ularity, maintainability, aesthetics, and human interface features of the product. In fact, these are aspects of the products that often are instrumental in deter­ mining its success or failure in the marketplace. Optimizing these and other product features is the primary role of Electronic Equipment Packaging Technology. As the electronics industry continues to pr...

  6. CV equipment responsibilities

    CERN Document Server

    Pirollet, B

    2008-01-01

    This document describes the limits of the responsibilities of the TS/CV for fire fighting equipment at the LHC. The various interfaces, providers and users of the water supply systems and clean water raising systems are described.

  7. Equipment for hydraulic testing

    International Nuclear Information System (INIS)

    Jacobsson, L.; Norlander, H.

    1981-07-01

    Hydraulic testing in boreholes is one major task of the hydrogeological program in the Stripa Project. A new testing equipment for this purpose was constructed. It consists of a downhole part and a surface part. The downhole part consists of two packers enclosing two test-sections when inflated; one between the packers and one between the bottom packer and the bottom of the borehole. A probe for downhole electronics is also included in the downhole equipment together with electrical cable and nylon tubing. In order to perform shut-in and pulse tests with high accuracy a surface controlled downhole valve was constructed. The surface equipment consists of the data acquisition system, transducer amplifier and surface gauges. In the report detailed descriptions of each component in the whole testing equipment are given. (Auth.)

  8. Experience with rotating equipment in FBTR

    International Nuclear Information System (INIS)

    Babu, A.; Subramanian, K.G.; Selvam, B.

    2006-01-01

    Fast breeder test reactor (FBTR) is a 40MWth sodium cooled PuC-UC fuelled fast breeder reactor located at Kalpakkam, Tamilnadu. FBTR has a variety of mechanical and electrical equipment comprising of single stage and multi stage water pumps, sodium pumps, compressors, Chiller units, Diesel Generator sets, vacuum pumps, ventilation fans, Turbo generator etc. The degree and extent of maintenance on these equipment are decided based on nuclear safety, station technical specification requirements, design criteria and operating philosophy. The variety and complexity of the equipment in FBTR demands various maintenance strategies (preventive, predictive, proactive etc.) for their upkeep. This paper discusses the performance of all mechanical and electrical equipment in FBTR, measures taken for their upkeep, major modifications done to prevent recurring failures, condition monitoring programme implemented, Maintenance Management and Information System developed for data acquisition and dissemination, etc. (author)

  9. A review of porosity-generating mechanisms in crustal shear zones

    Science.gov (United States)

    Fusseis, F.; Regenauer-Lieb, K.; Revets, S.

    2009-04-01

    Knowledge of the spatiotemporal characteristics of permeability is critical for the understanding of fluid migration in rocks. In diagenetic and metamorphic rocks different porosity-generating mechanisms contribute to permeability and so influence fluid migration and fluid/rock interaction. However, little is known about their relative contributions to the porosity architecture of a rock in a tectono-metamorphic environment. This presentation reviews porosity-generating mechanisms that affect fluid migration in shear zones, the most important crustal fluid conduits, in the context of the tectonometamorphic evolution of rocks. Mechanisms that generate porosity can be classified in a) those that involve the direct action of a fluid, b) processes in which a fluid partakes or that are supported by a fluid or c) mechanism that do not involve a fluid. a) Hydraulic fracturing, where it happens through the formation of tensile fractures, occurs where pore fluid pressures equalize the combined lithostatic pressure and strength of the rock (Etheridge et al., 1984, Cox & Etheridge, 1989, Oliver, 1996). Here an internally released (devolatilisation reactions, e.g., Rumble, 1994, Hacker, 1997, Yardley, 1997 and references therein) or externally derived (infiltrating from metamorphic, magmatic or meteoric sources, Baumgartner et al., 1997, Jamtveit et al., 1997, Thompson, 1997, Gleeson et al., 2003) fluid directly causes the mechanical failure of a rock. Where a fluid is in chemical disequilibrium with a rock (undersaturated with regard to a chemical species) minerals will be dissolved, generating dissolution porosity. Rocks ‘leached' by the removal of chemical components by vast amounts of fluid are reported to lose up to 60% of their original volume (e.g., Kerrich et al., 1984, McCaig 1988). Dissolution porosity is probably an underrated porosity-generating mechanism. It can be expected along the entire metamorphic evolution, including diagenesis (Higgs et al., 2007) and

  10. A technical review of liquid/liquid and solid/liquid separation equipment in the field of nuclear-fuel reprocessing

    International Nuclear Information System (INIS)

    Vassallo, G.

    1981-01-01

    Liquid/liquid extraction is generally accepted as the preferred method in nuclear-fuel reprocessing. However, although many types of liquid/liquid contactors are available, only a few meet the stringent specifications set by the nuclear industry. This report discusses the criteria for contactor selection and then reviews the most important types, namely packed columns, pulsed columns, mixer-setters and centrifugal contactors. Finally, a short section concerned with solid/liquid separations is included because of the possible deleterious effects caused by solids in liquid/liquid contactors

  11. Intestinal uptake of bone seeking radiotracer: possible mechanisms and review of the literature

    Energy Technology Data Exchange (ETDEWEB)

    Kim, D. W.; Kim, C. G.; Park, S. A.; Chang, J. A. [WonKwang University Hospital, Iksan (Korea, Republic of)

    2007-07-01

    This study was undertaken to investigate the frequency of intestinal accumulation of Tc-99m 3, 3-diphosphono-1, 2-propanedicarboxylic acid (DPD) on bone scans, describe the patterns of intestinal Tc-99m DPD uptake and discuss the possible mechanisms of this unusual finding. Three thousand, one hundred and ninety-four consecutive patients have been evaluated for intestinal Tc-99m DPD uptake on bone scans. A whole-body bone scan and various spot views were obtained to evaluate the location and intensity of intestinal uptake. Delayed scan and SPECT study were performed to define characteristics of intestinal uptake in some of patients. Available reports of co-relative radiologic imaging, endoscopic studies and laboratory tests were also reviewed to explain the intestinal uptake. Eighteen (9 female, 9 male) patients out of 3194 with a mean age of 57 years showed intestinal Tc-99m DPD uptake. The locations of intestinal uptake were well dispersed throughout the abdomen. The majority of the cases showed lower intensity than iliac spine (12/18, 67%). Eight patients didn't show significant change of uptake characteristics on the delayed images, while intestinal uptake traveled distally in nine patients. Two cases were revealed uptake of peritoneal carcinomatosis with small amount ascites and three cases were revealed tumoral uptake of intestine. Four patients with gastritis showed similar characteristic of intestinal uptake. Six cases of distally traveled intestinal uptake suggested intraluminal Tc-99m DPD activity such as gastrointestinal bleeding. However, stool occult blood tests were negative in three patients, and there is no clinical evidence of gastrointestinal bleeding in other three patients. Intestinal Tc-99m DPD uptake can be observed in 0.5% of bone scans. The mechanism of intestinal uptake is still unclear in some of the patients. Delayed imaging additional spot views and SPECT studies help in the differentiation of this finding from possible

  12. Pembrolizumab-Induced Thyroiditis: Comprehensive Clinical Review and Insights Into Underlying Involved Mechanisms.

    Science.gov (United States)

    Delivanis, Danae A; Gustafson, Michael P; Bornschlegl, Svetlana; Merten, Michele M; Kottschade, Lisa; Withers, Sarah; Dietz, Allan B; Ryder, Mabel

    2017-08-01

    Thyroid immune-related adverse events (irAEs) in patients treated with programmed death receptor-1 (PD-1) blockade are increasingly recognized as one of the most common adverse effects. Our aim was to determine the incidence and examine the potential mechanisms of anti-PD-1-induced thyroid irAEs. Single-center, retrospective cohort study. We studied 93 patients with advanced cancer (ages 24 to 82 years; 60% males) who received at least one infusion of pembrolizumab. Thyroid test results and thyroid imaging modalities were reviewed. Comprehensive 10-color flow cytometry of peripheral blood was performed. Thirteen (14%) thyroid irAEs were observed. Thyroiditis occurred in seven patients (54%), from which four recovered. New onset of hypothyroidism overt/subclinical developed in three patients. Levothyroxine dosing required doubling in three patients with a known history of hypothyroidism. Thyroperoxidase antibodies were positive in the minority of the patients [4/13 (31%)] and diffuse increased 18fludeoxyglucose uptake of the thyroid gland was observed in the majority [7/11 (64%)] of patients. We observed more circulating CD56+CD16+ natural killer (NK) cells and an elevated HLA-DR surface expression in the inflammatory intermediate CD14+CD16+ monocytes in anti-PD-1-treated patients. Thyroid dysfunction is common in cancer patients treated with pembrolizumab. Reversible destructive thyroiditis and overt hypothyroidism are the most common clinical presentations. The mechanism of thyroid destruction appears independent of thyroid autoantibodies and may include T cell, NK cell, and/or monocyte-mediated pathways. Because the thyroid is a frequent target of anti-PD-1 therapies, patients with therapeutically refractory thyroid cancer may be ideal candidates for this treatment. Copyright © 2017 Endocrine Society

  13. Mechanisms of silver diamine fluoride on arresting caries: a literature review.

    Science.gov (United States)

    Zhao, Irene Shuping; Gao, Sherry Shiqian; Hiraishi, Noriko; Burrow, Michael Francis; Duangthip, Duangporn; Mei, May Lei; Lo, Edward Chin-Man; Chu, Chun-Hung

    2018-04-01

    To review the evidence regarding the mechanisms of silver diamine fluoride (SDF) for arresting caries. A literature search was conducted using the keywords silver diamine fluoride, and its alternative names, in seven databases: PubMed, Embase and Scopus (English); China National Knowledge Infrastructure (Chinese); Bilioteca Virtual em Saude (Portuguese); Biblioteca Virtual en Salud Espana (Spanish); and Ichushi-Web (Japanese). The titles and abstracts were screened. Full texts were retrieved for publications that studied mechanisms of actions of SDF, including its effects on remineralisation of carious lesions and on cariogenic bacteria. A total of 1,123 publications were identified. Twenty-nine articles were included and they investigated the effect of SDF on cariogenic bacteria and dental hard tissues. Eleven studies investigated the antibacterial properties of SDF. They found that SDF was bactericidal to cariogenic bacteria, mainly Streptococcus mutans. It inhibited the growth of cariogenic biofilms on teeth. Twenty studies reported the remineralisation of demineralised enamel or dentine by SDF. They found that mineral loss of demineralised enamel and dentine was reduced after SDF treatment. A highly mineralised surface rich in calcium and phosphate was formed on arrested carious lesions. Four studies examined the effect of SDF on dentine collagen. They found that SDF inhibited collagenases (matrix metalloproteinases and cysteine cathepsins) and protected dentine collagen from destruction. SDF is a bactericidal agent and reduces the growth of cariogenic bacteria. It inhibits demineralisation and promotes the remineralisation of demineralised enamel and dentine. It also hampers degradation of the dentine collagen. © 2017 FDI World Dental Federation.

  14. A Review of Consequences of Poverty on Economic Decision-Making: A Hypothesized Model of a Cognitive Mechanism

    OpenAIRE

    Adamkovič, Matúš; Martončik, Marcel

    2017-01-01

    This review focuses on the issue of poverty affecting economic decision-making. By critically evaluating existing studies, the authors propose a structural model detailing the cognitive mechanism involved in how poverty negatively impacts economic decision-making, and explores evidence supporting the basis for the formation of this model. The suggested mechanism consists of a relationship between poverty and four other factors: (1) cognitive load (e.g., experiencing negative affect and stress...

  15. Equipment for x- and gamma ray radiography

    International Nuclear Information System (INIS)

    Abd Nasir Ibrahim; Azali Muhammad; Ab Razak Hamzah; Abd Aziz Mohamed; Mohammad Pauzi Ismail

    2004-01-01

    The following topics related to the equipment for x - and gamma ray radiography are discussed in this chapter. The topics are x-ray source for Industrial Radiography: properties of x-ray, generation of x-ray, mechanism of x-ray production, x-ray equipment, power supply, distribution of x-ray intensity along the tube: gamma ray source for Industrial Radiography: properties of gamma rays, gamma ray sources, gamma ray projectors on cameras, source changing. Care of Radiographic Equipments: Merits and Demerits of x and Gamma Rays

  16. The french safety approach regarding equipment qualification

    International Nuclear Information System (INIS)

    Jalouneix, J.; Deletre, G.; Henry, J.Y.; Rousseau, L.

    1989-10-01

    The qualification of the equipment, used in France on nuclear reactors and reactor components, is discussed. The approach on safety involves the qualification of mechanical and electrical components, under operating and under seismic conditions. The principles of the qualification program and the list of the equipment concerned, are given. The conditions in which qualification tests are performed and the methods applied, are summarized. The actions for preserving the qualification procedures, are considered

  17. Conceptual design report for the mechanical disassembly of Fort St. Vrain fuel elements

    Energy Technology Data Exchange (ETDEWEB)

    Lord, D.L. [Westinghouse Idaho Nuclear Co., Inc., Idaho Falls, ID (United States); Wadsworth, D.C.; Sekot, J.P.; Skinner, K.L. [EG and G Idaho, Inc., Idaho Falls, ID (United States)

    1993-04-01

    A conceptual design study was prepared that: (1) reviewed the operations necessary to perform the mechanical disassembly of Fort St. Vrain fuel elements; (2) contained a description and survey of equipment capable of performing the necessary functions; and (3) performed a tradeoff study for determining the preferred concepts and equipment specifications. A preferred system was recommended and engineering specifications for this system were developed.

  18. Conceptual design report for the mechanical disassembly of Fort St. Vrain fuel elements

    International Nuclear Information System (INIS)

    Lord, D.L.; Wadsworth, D.C.; Sekot, J.P.; Skinner, K.L.

    1993-04-01

    A conceptual design study was prepared that: (1) reviewed the operations necessary to perform the mechanical disassembly of Fort St. Vrain fuel elements; (2) contained a description and survey of equipment capable of performing the necessary functions; and (3) performed a tradeoff study for determining the preferred concepts and equipment specifications. A preferred system was recommended and engineering specifications for this system were developed

  19. Mixing enhancement strategies and their mechanisms in supersonic flows: A brief review

    Science.gov (United States)

    Huang, Wei

    2018-04-01

    Achieving efficient fuel-air mixing is a crucial issue in the design of the scramjet engine due to the compressibility effect on the mixing shear layer growth and the stringent flow residence time limitation induced by the high-speed crossflow, and the potential solution is to enhance mixing between air and fuel by introducing of streamwise vortices in the flow field. In this survey, some mixing enhancement strategies based on the traditional transverse injection technique proposed in recent years, as well as their mixing augmentation mechanisms, were reviewed in detail, namely the pulsed transverse injection scheme, the traditional transverse injection coupled with the vortex generator, and the dual transverse injection system with a front porthole and a rear air porthole arranged in tandem. The streamwise vortices, through the large-scale stirring motion that they introduce, are responsible for the extraction of large amounts of energy from the mean flow that can be converted into turbulence, ultimately leading to increased mixing effectiveness. The streamwise vortices may be obtained by taking advantage of the shear layer between a jet and the cross stream or by employing intrusive physical devices. Finally, a promising mixing enhancement strategy in supersonic flows was proposed, and some remarks were provided.

  20. Parallel computing in experimental mechanics and optical measurement: A review (II)

    Science.gov (United States)

    Wang, Tianyi; Kemao, Qian

    2018-05-01

    With advantages such as non-destructiveness, high sensitivity and high accuracy, optical techniques have successfully integrated into various important physical quantities in experimental mechanics (EM) and optical measurement (OM). However, in pursuit of higher image resolutions for higher accuracy, the computation burden of optical techniques has become much heavier. Therefore, in recent years, heterogeneous platforms composing of hardware such as CPUs and GPUs, have been widely employed to accelerate these techniques due to their cost-effectiveness, short development cycle, easy portability, and high scalability. In this paper, we analyze various works by first illustrating their different architectures, followed by introducing their various parallel patterns for high speed computation. Next, we review the effects of CPU and GPU parallel computing specifically in EM & OM applications in a broad scope, which include digital image/volume correlation, fringe pattern analysis, tomography, hyperspectral imaging, computer-generated holograms, and integral imaging. In our survey, we have found that high parallelism can always be exploited in such applications for the development of high-performance systems.

  1. Flavonoids Active Against Osteosarcoma: A Review of the Molecular Mechanisms Involved.

    Science.gov (United States)

    Liu, Hui; Gao, Yutong; Dong, Yonghui; Cheng, Peng; Chen, Anmin; Huang, Hui

    2017-01-01

    Osteosarcoma is the most frequent primitive malignant bone tumor affecting adolescents and young adults worldwide. The tumor exhibits aggressive growth in the primary site and readily metastasizes to other organs. There has been no significant improvement in the 5-year survival rate since the 1970s and the figure remains at 60-70%. In addition, the side effects of chemotherapeutic drugs and resistance to chemotherapy compromise the effects of treatment for osteosarcoma. In recent years, the development of flavonoids drugs inhibiting carcinogenesis is attracting great interest in the scientific community. Flavonoids are one kind of polyphenolic compounds widely found in vegetables and fruits. Moreover, flavonoids have become popular compounds, exhibiting comprehensive antitumor activities, while being safe and inexpensive. Here, the literature on the benefits afforded by flavonoids in terms of osteosarcoma treatment is reviewed and certain flavonoids and their effects on osteosarcoma are discussed. These compounds can perturb the cell cycle, induce apoptosis, inhibit tumor cell invasion and metastasis, potentiate the actions of chemotherapeutic agents, trigger autophagy, and stimulate antitumor activity in vivo. In summary, we highlight the currently well-accepted flavonoid compounds and detail the molecular mechanisms by which flavonoids may treat osteosarcoma, and thus the flavonoids exhibit great promise as anti-osteosarcoma agents. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  2. Perceptual and affective mechanisms in facial expression recognition: An integrative review.

    Science.gov (United States)

    Calvo, Manuel G; Nummenmaa, Lauri

    2016-09-01

    Facial expressions of emotion involve a physical component of morphological changes in a face and an affective component conveying information about the expresser's internal feelings. It remains unresolved how much recognition and discrimination of expressions rely on the perception of morphological patterns or the processing of affective content. This review of research on the role of visual and emotional factors in expression recognition reached three major conclusions. First, behavioral, neurophysiological, and computational measures indicate that basic expressions are reliably recognized and discriminated from one another, albeit the effect may be inflated by the use of prototypical expression stimuli and forced-choice responses. Second, affective content along the dimensions of valence and arousal is extracted early from facial expressions, although this coarse affective representation contributes minimally to categorical recognition of specific expressions. Third, the physical configuration and visual saliency of facial features contribute significantly to expression recognition, with "emotionless" computational models being able to reproduce some of the basic phenomena demonstrated in human observers. We conclude that facial expression recognition, as it has been investigated in conventional laboratory tasks, depends to a greater extent on perceptual than affective information and mechanisms.

  3. Transcranial alternating current stimulation: A review of the underlying mechanisms and modulation of cognitive processes

    Directory of Open Access Journals (Sweden)

    Christoph S Herrmann

    2013-06-01

    Full Text Available Brain oscillations of different frequencies have been associated with a variety of cognitive functions. Convincing evidence supporting those associations has been provided by studies using intracranial stimulation, pharmacological interventions and lesion studies. The emergence of novel non-invasive brain stimulation techniques like repetitive transcranial magnetic stimulation (rTMS and transcranial alternating current stimulation (tACS now allows to modulate brain oscillations directly. Particularly, tACS offers the unique opportunity to causally link brain oscillations of a specific frequency range to cognitive processes, because it uses sinusoidal currents that are bound to one frequency only. Using tACS allows to modulate brain oscillations and in turn to influence cognitive processes, thereby demonstrating the causal link between the two. Here, we review findings about the physiological mechanism of tACS and studies that have used tACS to modulate basic motor and sensory processes as well as higher cognitive processes like memory, ambiguous perception, and decision making.

  4. Exploring the Molecular Mechanisms of Nickel-Induced Genotoxicity and Carcinogenicity: A Literature Review

    Science.gov (United States)

    Cameron, Keyuna S.; Buchner, Virginia; Tchounwou, Paul B.

    2011-01-01

    Nickel, a naturally occurring element that exists in various mineral forms, is mainly found in soil and sediment, and its mobilization is influenced by the physicochemical properties of the soil. Industrial sources of nickel include metallurgical processes such as electroplating, alloy production, stainless steel, and nickel-cadmium batteries. Nickel industries, oil- and coal-burning power plants, and trash incinerators have been implicated in its release into the environment. In humans, nickel toxicity is influenced by the route of exposure, dose, and solubility of the nickel compound. Lung inhalation is the major route of exposure for nickel-induced toxicity. Nickel may also be ingested or absorbed through the skin. The primary target organs are the kidneys and lungs. Other organs such as the liver, spleen, heart and testes may also be affected to a lesser extent. Although the most common health effect is an allergic reaction, research has also demonstrated that nickel is carcinogenic to humans. The focus of the present review is on recent research concerning the molecular mechanisms of nickel-induced genotoxicity and carcinogenicity. We first present a background on the occurrence of nickel in the environment, human exposure, and human health effects. PMID:21905451

  5. Epigenetic Mechanisms Shape the Biological Response to Trauma and Risk for PTSD: A Critical Review

    Directory of Open Access Journals (Sweden)

    Morgan Heinzelmann

    2013-01-01

    Full Text Available Posttraumatic stress disorder (PTSD develops in approximately one-quarter of trauma-exposed individuals, leading us and others to question the mechanisms underlying this heterogeneous response to trauma. We suggest that the reasons for the heterogeneity relate to a complex interaction between genes and the environment, shaping each individual’s recovery trajectory based on both historical and trauma-specific variables. Epigenetic modifications provide a unique opportunity to elucidate how preexisting risk factors may contribute to PTSD risk through changes in the methylation of DNA. Preexisting risks for PTSD, including depression, stress, and trauma, result in differential DNA methylation of endocrine genes, which may then result in a different biological responses to trauma and subsequently a greater risk for PTSD onset. Although these relationships are complex and currently inadequately described, we provide a critical review of recent studies to examine how differences in genetic and proteomic biomarkers shape an individual’s vulnerability to PTSD development, thereby contributing to a heterogeneous response to trauma.

  6. Gadolinium-based contrast agent toxicity: a review of known and proposed mechanisms.

    Science.gov (United States)

    Rogosnitzky, Moshe; Branch, Stacy

    2016-06-01

    Gadolinium chelates are widely used as contrast media for magnetic resonance imaging. The approved gadolinium-based contrast agents (GBCAs) have historically been considered safe and well tolerated when used at recommended dosing levels. However, for nearly a decade, an association between GBCA administration and the development of nephrogenic systemic fibrosis (NSF) has been recognized in patients with severe renal impairment. This has led to modifications in clinical practices aimed at reducing the potential and incidence of NSF development. Newer reports have emerged regarding the accumulation of gadolinium in various tissues of patients who do not have renal impairment, including bone, brain, and kidneys. Despite the observations of gadolinium accumulation in tissues regardless of renal function, very limited clinical data regarding the potential for and mechanisms of toxicity is available. This significant gap in knowledge warrants retrospective cohort study efforts, as well as prospective studies that involve gadolinium ion (Gd(3+)) testing in patients exposed to GBCA. This review examines the potential biochemical and molecular basis of gadolinium toxicity, possible clinical significance of gadolinium tissue retention and accumulation, and methods that can limit gadolinium body burden.

  7. Ultrasound assisted extraction of food and natural products. Mechanisms, techniques, combinations, protocols and applications. A review.

    Science.gov (United States)

    Chemat, Farid; Rombaut, Natacha; Sicaire, Anne-Gaëlle; Meullemiestre, Alice; Fabiano-Tixier, Anne-Sylvie; Abert-Vian, Maryline

    2017-01-01

    This review presents a complete picture of current knowledge on ultrasound-assisted extraction (UAE) in food ingredients and products, nutraceutics, cosmetic, pharmaceutical and bioenergy applications. It provides the necessary theoretical background and some details about extraction by ultrasound, the techniques and their combinations, the mechanisms (fragmentation, erosion, capillarity, detexturation, and sonoporation), applications from laboratory to industry, security, and environmental impacts. In addition, the ultrasound extraction procedures and the important parameters influencing its performance are also included, together with the advantages and the drawbacks of each UAE techniques. Ultrasound-assisted extraction is a research topic, which affects several fields of modern plant-based chemistry. All the reported applications have shown that ultrasound-assisted extraction is a green and economically viable alternative to conventional techniques for food and natural products. The main benefits are decrease of extraction and processing time, the amount of energy and solvents used, unit operations, and CO 2 emissions. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Molecular mechanisms of obesity induced osteoporosis and muscle atrophy: A Review

    Directory of Open Access Journals (Sweden)

    Bipradas Roy

    2016-09-01

    Full Text Available Obesity and osteoporosis are two alarming health disorders prominent among middle and old age populations, and the numbers of those affected by these two disorders are increasing. It is estimated that more than 600 million adults are obese and over 200 million people have osteoporosis worldwide. Interestingly, both of these abnormalities share some common features including a genetic predisposition, and a common origin: bone marrow mesenchymal stromal cells. Obesity is characterized by the expression of leptin, adiponectin, interleukin 6 (IL-6, interleukin 10 (IL-10, monocyte chemotactic protein-1 (MCP-1, tumor necrosis factor-alpha (TNF-α, macrophage colony stimulating factor (M-CSF, growth hormone (GH, parathyroid hormone (PTH, angiotensin II (Ang II, 5-hydroxy-tryptamine (5-HT, Advance glycation end products (AGE, and myostatin, which exert their effects by modulating the signaling pathways within bone and muscle. Chemical messengers (eg. TNF-α, IL-6, AGE, leptins that are upregulated or downregulated as a result of obesity have been shown to act as negative regulators of osteoblasts, osteocytes and muscles, as well as positive regulators of osteoclasts. These additive effects of obesity ultimately increase the risk for osteoporosis and muscle atrophy. The aim of this review is to identify the potential cellular mechanisms through which obesity may facilitate osteoporosis, muscle atrophy and bone fractures.

  9. From evidence based medicine to mechanism based medicine. Reviewing the role of pharmacogenetics.

    Science.gov (United States)

    Wilffert, Bob; Swen, Jesse; Mulder, Hans; Touw, Daan; Maitland-Van der Zee, Anke-Hilse; Deneer, Vera

    2013-06-01

    The translation of evidence based medicine to a specific patient presents a considerable challenge. We present by means of the examples nortriptyline, tramadol, clopidogrel, coumarins, abacavir and antipsychotics the discrepancy between available pharmacogenetic information and its implementation in daily clinical practice. Literature review. A mechanism based approach may be helpful to personalize medicine for the individual patient to which pharmacogenetics may contribute significantly. The lack of consistency in what we accept in bioequivalence and in pharmacogenetics of drug metabolising enzymes is discussed and illustrated with the example of nortriptyline. The impact of pharmacogenetics on examples like tramadol, clopidogrel, coumarins and abacavir is described. Also the present status of the polymorphisms of 5-HT2A and C receptors in antipsychotic-induced weight gain is presented as a pharmacodynamic example with until now a greater distance to clinical implementation. The contribution of pharmacogenetics to tailor-made pharmacotherapy, which especially might be of value for patients deviating from the average, has not yet reached the position it seems to deserve.

  10. A Review of Continuing Professional Development (CPD of Training Competencies for Malaysian Mechanical Industries

    Directory of Open Access Journals (Sweden)

    Kasman Zeti

    2018-01-01

    Full Text Available The aim of this paper is to review issues in continuing professional development of vocational training to the mechanical industries. The spectacle of individuals entering the labour market without relevant qualifications is common in Malaysia. There are many who choose to work instead of pursuing further education after secondary school. In the labour market, these individuals are considered to be low-skilled workers because they had no training prior to employment. The role of employers in providing training and education to employees is vital in establishing career development of employees. Employers who contributed to their employees' training funds through Human Resources Development Council would provide opportunities to increase the skills of workers. Based on the Malaysia's Development Plan of Occupational Skill, the issues and challenges that have been identified in producing skilled workers in interpersonal and technical skills. This paper provided an opportunity to examine an enterprise-based approach to skill formation for workers with basic academic qualifications. It presents an alternative scenario to institution-based Technical and Vocational Education and Training (TVET, which many Malaysians are familiar with. A structured curriculum development of human resources learning needs according to the job profile of the typical individual and group work which will provide a clearer perspective on knowledge, competence and skill levels of employee behavior in performing tasks will be discussed. The biggest impact on this study is to produce high skill employees concerning customer satisfaction and increased organizational productivity towards high income nations.

  11. SEURAT-1 liver gold reference compounds: a mechanism-based review.

    Science.gov (United States)

    Jennings, Paul; Schwarz, Michael; Landesmann, Brigitte; Maggioni, Silvia; Goumenou, Marina; Bower, David; Leonard, Martin O; Wiseman, Jeffrey S

    2014-12-01

    There is an urgent need for the development of alternative methods to replace animal testing for the prediction of repeat dose chemical toxicity. To address this need, the European Commission and Cosmetics Europe have jointly funded a research program for 'Safety Evaluation Ultimately Replacing Animal Testing.' The goal of this program was the development of in vitro cellular systems and associated computational capabilities for the prediction of hepatic, cardiac, renal, neuronal, muscle, and skin toxicities. An essential component of this effort is the choice of appropriate reference compounds that can be used in the development and validation of assays. In this review, we focus on the selection of reference compounds for liver pathologies in the broad categories of cytotoxicity and lipid disorders. Mitochondrial impairment, oxidative stress, and apoptosis are considered under the category of cytotoxicity, while steatosis, cholestasis, and phospholipidosis are considered under the category of lipid dysregulation. We focused on four compound classes capable of initiating such events, i.e., chemically reactive compounds, compounds with specific cellular targets, compounds that modulate lipid regulatory networks, and compounds that disrupt the plasma membrane. We describe the molecular mechanisms of these compounds and the cellular response networks which they elicit. This information will be helpful to both improve our understanding of mode of action and help in the selection of appropriate mechanistic biomarkers, allowing us to progress the development of animal-free models with improved predictivity to the human situation.

  12. How do Small Groups Promote Behaviour Change? An Integrative Conceptual Review of Explanatory Mechanisms.

    Science.gov (United States)

    Borek, Aleksandra J; Abraham, Charles

    2018-03-01

    Small groups are used to promote health, well-being, and personal change by altering members' perceptions, beliefs, expectations, and behaviour patterns. An extensive cross-disciplinary literature has articulated and tested theories explaining how such groups develop, function, and facilitate change. Yet these theoretical understandings are rarely applied in the development, description, and evaluation of health-promotion, group-based, behaviour-change interventions. Medline database, library catalogues, search engines, specific journals and reference lists were searched for relevant texts. Texts were reviewed for explanatory concepts or theories describing change processes in groups, which were integrated into the developing conceptual structure. This was designed to be a parsimonious conceptual framework that could be applied to design and delivery. Five categories of interacting processes and concepts were identified and defined: (1) group development processes, (2) dynamic group processes, (3) social change processes, (4) personal change processes, and (5) group design and operating parameters. Each of these categories encompasses a variety of theorised mechanisms explaining individual change in small groups. The final conceptual model, together with the design issues and practical recommendations derived from it, provides a practical basis for linking research and theory explaining group functioning to optimal design of group-based, behaviour-change interventions. © 2018 The Authors. Applied Psychology: Health and Well-Being published by John Wiley & Sons Ltd on behalf of International Association of Applied Psychology.

  13. Alpha-2 agonists for sedation of mechanically ventilated adults in intensive care units: a systematic review.

    Science.gov (United States)

    Cruickshank, Moira; Henderson, Lorna; MacLennan, Graeme; Fraser, Cynthia; Campbell, Marion; Blackwood, Bronagh; Gordon, Anthony; Brazzelli, Miriam

    2016-03-01

    Care of critically ill patients in intensive care units (ICUs) often requires potentially invasive or uncomfortable procedures, such as mechanical ventilation (MV). Sedation can alleviate pain and discomfort, provide protection from stressful or harmful events, prevent anxiety and promote sleep. Various sedative agents are available for use in ICUs. In the UK, the most commonly used sedatives are propofol (Diprivan(®), AstraZeneca), benzodiazepines [e.g. midazolam (Hypnovel(®), Roche) and lorazepam (Ativan(®), Pfizer)] and alpha-2 adrenergic receptor agonists [e.g. dexmedetomidine (Dexdor(®), Orion Corporation) and clonidine (Catapres(®), Boehringer Ingelheim)]. Sedative agents vary in onset/duration of effects and in their side effects. The pattern of sedation of alpha-2 agonists is quite different from that of other sedatives in that patients can be aroused readily and their cognitive performance on psychometric tests is usually preserved. Moreover, respiratory depression is less frequent after alpha-2 agonists than after other sedative agents. To conduct a systematic review to evaluate the comparative effects of alpha-2 agonists (dexmedetomidine and clonidine) and propofol or benzodiazepines (midazolam and lorazepam) in mechanically ventilated adults admitted to ICUs. We searched major electronic databases (e.g. MEDLINE without revisions, MEDLINE In-Process & Other Non-Indexed Citations, EMBASE and Cochrane Central Register of Controlled Trials) from 1999 to 2014. Evidence was considered from randomised controlled trials (RCTs) comparing dexmedetomidine with clonidine or dexmedetomidine or clonidine with propofol or benzodiazepines such as midazolam, lorazepam and diazepam (Diazemuls(®), Actavis UK Limited). Primary outcomes included mortality, duration of MV, length of ICU stay and adverse events. One reviewer extracted data and assessed the risk of bias of included trials. A second reviewer cross-checked all the data extracted. Random-effects meta

  14. A review of mechanical move sprinkler irrigation control and automation technologies

    Science.gov (United States)

    Electronic sensors, equipment controls, and communication protocols have been developed to meet the growing interest in site-specific irrigation using center pivot and lateral move irrigation systems. Onboard and field-distributed sensors can collect data necessary for real-time irrigation manageme...

  15. A Critical Review of Consumer Wearables, Mobile Applications, and Equipment for Providing Biofeedback, Monitoring Stress, and Sleep in Physically Active Populations

    Directory of Open Access Journals (Sweden)

    Jonathan M. Peake

    2018-06-01

    Full Text Available The commercial market for technologies to monitor and improve personal health and sports performance is ever expanding. A wide range of smart watches, bands, garments, and patches with embedded sensors, small portable devices and mobile applications now exist to record and provide users with feedback on many different physical performance variables. These variables include cardiorespiratory function, movement patterns, sweat analysis, tissue oxygenation, sleep, emotional state, and changes in cognitive function following concussion. In this review, we have summarized the features and evaluated the characteristics of a cross-section of technologies for health and sports performance according to what the technology is claimed to do, whether it has been validated and is reliable, and if it is suitable for general consumer use. Consumers who are choosing new technology should consider whether it (1 produces desirable (or non-desirable outcomes, (2 has been developed based on real-world need, and (3 has been tested and proven effective in applied studies in different settings. Among the technologies included in this review, more than half have not been validated through independent research. Only 5% of the technologies have been formally validated. Around 10% of technologies have been developed for and used in research. The value of such technologies for consumer use is debatable, however, because they may require extra time to set up and interpret the data they produce. Looking to the future, the rapidly expanding market of health and sports performance technology has much to offer consumers. To create a competitive advantage, companies producing health and performance technologies should consult with consumers to identify real-world need, and invest in research to prove the effectiveness of their products. To get the best value, consumers should carefully select such products, not only based on their personal needs, but also according to the

  16. Mechanics

    CERN Document Server

    Chester, W

    1979-01-01

    When I began to write this book, I originally had in mind the needs of university students in their first year. May aim was to keep the mathematics simple. No advanced techniques are used and there are no complicated applications. The emphasis is on an understanding of the basic ideas and problems which require expertise but do not contribute to this understanding are not discussed. How­ ever, the presentation is more sophisticated than might be considered appropri­ ate for someone with no previous knowledge of the subject so that, although it is developed from the beginning, some previous acquaintance with the elements of the subject would be an advantage. In addition, some familiarity with element­ ary calculus is assumed but not with the elementary theory of differential equations, although knowledge of the latter would again be an advantage. It is my opinion that mechanics is best introduced through the motion of a particle, with rigid body problems left until the subject is more fully developed. Howev...

  17. A review of recent studies on the mechanisms and analysis methods of sub-synchronous oscillation in wind farms

    Science.gov (United States)

    Wang, Chenggen; Zhou, Qian; Gao, Shuning; Luo, Jia; Diao, Junchao; Zhao, Haoran; Bu, Jing

    2018-04-01

    This paper reviews the recent studies of Sub-Synchronous Oscillation(SSO) in wind farms. Mechanisms and analysis methods are the main concerns of this article. A classification method including new types of oscillation occurred between wind farms and HVDC systems and oscillation caused by Permanent Magnet Synchronous Generators(PMSG) is proposed. Characteristics of oscillation analysis techniques are summarized.

  18. A review of the chemical and physical mechanisms of the storage stability of fast pyrolysis bio-oils

    Energy Technology Data Exchange (ETDEWEB)

    Diebold, J.P.

    1999-01-27

    Understanding the fundamental chemical and physical aging mechanisms is necessary to learn how to produce a bio-oil that is more stable during shipping and storage. This review provides a basis for this understanding and identifies possible future research paths to produce bio-oils with better storage stability.

  19. The effect of grinding on the mechanical behavior of Y-TZP ceramics: A systematic review and meta-analyses

    NARCIS (Netherlands)

    Pereira, G.K.R.; Fraga, S.; Montagner, A.F.; Soares, F.Z.M.; Kleverlaan, C.J.; Valandro, L.F.

    2016-01-01

    The aim of this study was to systematically review the literature to assess the effect of grinding on the mechanical properties, structural stability and superficial characteristics of Y-TZP ceramics. The MEDLINE via PubMed and Web of Science (ISI – Web of Knowledge) electronic databases were

  20. Book review: ALMOG, J. Referential Mechanics: Direct Reference and the Foundations of Semantics (Oxford University Press, 2014

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    Filipe Martone

    Full Text Available Abstract: In this review I discuss Joseph Almog's book "Referential Mechanics". The book discusses direct reference as conceived by three of its founding fathers, Kripke, Kaplan and Donnellan, and introduces Almog's ambitious project of providing a referential semantics to all subject-phrases. I offer a brief overview of its four chapters and point out some of their virtues and shortcomings.