WorldWideScience

Sample records for alloying physical review

  1. Vanadium alloys for structural applications in fusion systems: A review of vanadium alloy mechanical and physical properties

    Energy Technology Data Exchange (ETDEWEB)

    Loomis, B.A.; Smith, D.L.

    1991-12-16

    The current knowledge is reviewed on (1) the effects of neutron irradiation on tensile strength and ductility, ductile-brittle transition temperature, creep, fatigue, and swelling of vanadium-base alloys, (2) the compatibility of vanadium-base alloys with liquid lithium, water, and helium environments, and (3) the effects of hydrogen and helium on the physical and mechanical properties of vanadium alloys that are potential candidates for structural materials applications in fusion systems. Also, physical and mechanical properties issues are identified that have not been adequately investigated in order to qualify a vanadium-base alloy for the structural material in experimental fusion devices and/or in fusion reactors.

  2. Vanadium alloys for structural applications in fusion systems: A review of vanadium alloy mechanical and physical properties

    International Nuclear Information System (INIS)

    Loomis, B.A.; Smith, D.L.

    1991-01-01

    The current knowledge is reviewed on (1) the effects of neutron irradiation on tensile strength and ductility, ductile-brittle transition temperature, creep, fatigue, and swelling of vanadium-base alloys, (2) the compatibility of vanadium-base alloys with liquid lithium, water, and helium environments, and (3) the effects of hydrogen and helium on the physical and mechanical properties of vanadium alloys that are potential candidates for structural materials applications in fusion systems. Also, physical and mechanical properties issues are identified that have not been adequately investigated in order to qualify a vanadium-base alloy for the structural material in experimental fusion devices and/or in fusion reactors

  3. Review and study of physics driven pitting corrosion modeling in 2024-T3 aluminum alloys

    Science.gov (United States)

    Yu, Lingyu; Jata, Kumar V.

    2015-04-01

    Material degradation due to corrosion and corrosion fatigue has been recognized to significantly affect the airworthiness of civilian and military aircraft, especially for the current fleet of airplanes that have served beyond their initial design life. The ability to predict the corrosion damage development in aircraft components and structures, therefore, is of great importance in managing timely maintenance for the aging aircraft vehicles and in assisting the design of new ones. The assessment of aircraft corrosion and its influence on fatigue life relies on appropriate quantitative models that can evaluate the initiation of the corrosion as well as the accumulation during the period of operation. Beyond the aircraft regime, corrosion has also affected the maintenance, safety and reliability of other systems such as nuclear power systems, steam and gas turbines, marine structures and so on. In the work presented in this paper, we reviewed and studied several physics based pitting corrosion models that have been reported in the literature. The classic work of particle induced pitting corrosion by Wei and Harlow is reviewed in detail. Two types of modeling, a power law based simplified model and a microstructure based model, are compared for 2024-T3 alloy. Data from literatures are used as model inputs. The paper ends with conclusions and recommendations for future work.

  4. Metal-ceramic alloys in dentistry: a review.

    Science.gov (United States)

    Roberts, Howard W; Berzins, David W; Moore, B Keith; Charlton, David G

    2009-02-01

    The purpose of this article is to review basic information about the alloys used for fabricating metal-ceramic restorations in dentistry. Their compositions, properties, advantages, and disadvantages are presented and compared. In addition to reviewing traditional noble-metal and base-metal metal-ceramic alloys, titanium and gold composite alloys are also discussed. A broad search of the published literature was performed using Medline to identify pertinent current articles on metal-ceramic alloys as well as articles providing a historical background about the development of these alloys. Textbooks, the internet, and manufacturers' literature were also used to supplement this information. The review discusses traditional as well as more recently-developed alloys and technologies used in dentistry for fabricating metal-ceramic restorations. Clear advantages and disadvantages for these alloy types are provided and discussed as well as the role that compositional variations have on the alloys' performance. This information should enable clinicians and technicians to easily identify the important physical properties of each type and their primary clinical indications. A number of alloys and metals are available for metal-ceramic use in dentistry. Each has its advantages and disadvantages, primarily based on its specific composition. Continuing research and development are resulting in the production of new technologies and products, giving clinicians even more choices in designing and fabricating metal-ceramic restorations.

  5. Laser surface alloying on aluminum and its alloys: A review

    Science.gov (United States)

    Chi, Yiming; Gu, Guochao; Yu, Huijun; Chen, Chuanzhong

    2018-01-01

    Aluminum and its alloys have been widely used in aerospace, automotive and transportation industries owing to their excellent properties such as high specific strength, good ductility and light weight. Surface modification is of crucial importance to the surface properties of aluminum and its alloys since high coefficient of friction, wear characteristics and low hardness have limited their long term performance. Laser surface alloying is one of the most effective methods of producing proper microstructure by means of non-equilibrium solidification which results from rapid heating and cooling. In this paper, the influence of different processing parameters, such as laser power and scanning velocity is discussed. The developments of various material systems including ceramics, metals or alloys, and metal matrix composites (MMCs) are reviewed. The microstructure, hardness, wear properties and other behaviors of laser treated layer are analyzed. Besides, the existing problems during laser surface treatment and the corresponding solutions are elucidated and the future developments are predicted.

  6. Phosphorus containing sintered alloys (review)

    International Nuclear Information System (INIS)

    Muchnik, S.V.

    1984-01-01

    Phosphorus additives are considered for their effect on the properties of sintered alloys of different applications: structural, antifriction, friction, magnetic, hard, superhard, heavy etc. Data are presented on compositions and properties of phosphorus-containing materials produced by the powder metallurgy method. Phosphorus is shown to be an effective activator of sintering in some cases. When its concentration in the material is optimal it imparts the material such properties as strength, viscosity, hardness, wear resistance. Problems concerning powder metallurgy of amorphous phosphorus-containing alloys are reported

  7. Atomic structure and physical properties of liquid Pb Bi alloys

    Science.gov (United States)

    Kaban, I.; Hoyer, W.; Plevachuk, Yu; Sklyarchuk, V.

    2004-09-01

    The atomic structure and physical properties (dynamic viscosity, electrical conductivity, and thermopower) of liquid Pb-Bi alloys have been investigated in a wide temperature range. Gradual and reversible changes of the physical properties during heating and cooling of the Pb-Bi liquid alloys have been observed. No drastic structural transformations or atomic rearrangement with temperature variation have been found.

  8. Laser Surface Engineering of Magnesium Alloys: A Review

    Science.gov (United States)

    Singh, Ashish; Harimkar, Sandip P.

    2012-06-01

    Magnesium (Mg) and its alloys are well known for their high specific strength and low density. However, widespread applications of Mg alloys in structural components are impeded by their insufficient wear and corrosion resistance. Various surface engineering approaches, including electrochemical processes (plating, conversion coatings, hydriding, and anodizing), gas-phase deposition (thermal spray, chemical vapor deposition, physical vapor deposition, diamond-like coatings, diffusion coatings, and ion implantation), and organic polymer coatings (painting and powder coating), have been used to improve the surface properties of Mg and its alloys. Recently, laser surface engineering approaches are attracting significant attention because of the wide range of possibilities in achieving the desired microstructural and compositional modifications through a range of laser-material interactions (surface melting, shock peening, and ablation). This article presents a review of various laser surface engineering approaches such as laser surface melting, laser surface alloying, laser surface cladding, laser composite surfacing, and laser shock peening used for surface modification of Mg alloys. The laser-material interactions, microstructural/compositional changes, and properties development (mostly corrosion and wear resistance) accompanied with each of these approaches are reviewed.

  9. Reviews of plasma physics

    CERN Document Server

    2008-01-01

    "Reviews of Plasma Physics Volume 24," edited by V.D. Shafranov, presents two reviews from the cutting-edge of Russian plasma physics research. The first review by V.A. Rozhansky devoted to the mechanisms of transverse conductivity and generation of self-consistent electric fields in strongly ionized magnetized plasma. The second review by O.G. Bakunin considers numerous aspects of turbulent transport in plasma and fluids. This review is focused on scaling arguments for describing anomalous diffusion in the presence of complex structures. These topics are especially important for fusion plasma research, plasma astrophysics, discharge physics, and turbulence

  10. Charm physics: theoretical review

    OpenAIRE

    Petrov, Alexey A.

    2003-01-01

    We review recent developments in charm physics, focusing on the physics of charmed mesons. We discuss charm spectroscopy, decay constants, as well as searches for new physics with charmed mesons. We discuss D0-anti-D0 mixing and CP-violation in charm decays. We also present the modified Nelson plot of charm mixing predictions.

  11. Nickel-titanium alloys: a systematic review

    Directory of Open Access Journals (Sweden)

    Marcelo do Amaral Ferreira

    2012-06-01

    Full Text Available OBJECTIVE: A systematic review on nickel-titanium wires was performed. The strategy was focused on Entrez-PubMed-OLDMEDLINE, Scopus and BioMed Central from 1963 to 2008. METHODS: Papers in English and French describing the behavior of these wires and laboratorial methods to identify crystalline transformation were considered. A total of 29 papers were selected. RESULTS: Nickel-titanium wires show exceptional features in terms of elasticity and shape memory effects. However, clinical applications request a deeper knowledge of these properties in order to allow the professional to use them in a rational manner. In addition, the necessary information regarding each alloy often does not correspond to the information given by the manufacturer. Many alloys called "superelastic" do not present this effect; they just behave as less stiff alloys, with a larger springback if compared to the stainless steel wires. CONCLUSIONS: Laboratory tests are the only means to observe the real behavior of these materials, including temperature transition range (TTR and applied tensions. However, it is also possible to determine in which TTR these alloys change the crystalline structure.

  12. Charm physics: theoretical review

    International Nuclear Information System (INIS)

    Petrov, Alexey A.

    2003-01-01

    Charm physics plays a unique dual role in the modern investigation of flavor physics. Charm decay and production experiments provide valuable checks and supporting measurements for studies of CP-violation in measurements of CKM parameters in b-physics, as well as outstanding opportunities for searches for new physics. Historically, many methods of heavy quark physics have been first tested in charmed hadrons. The fact that a b-quark mainly decays into a charm quark makes charm physics an integral part of any b-physics program. In many cases direct measurements of charm decay parameters directly affect the studies of fundamental physics in B decays. This year brought several interesting developments in some seemingly well-understood sectors of charm physics, such as meson spectroscopy. We review recent developments in charm physics, focusing on the physics of charmed mesons. We discuss charm spectroscopy, decay constants and transition form factors, as well as searches for new physics with charmed mesons. We discuss D 0 D 0 -bar mixing and CP-violation in charm decays. (author)

  13. A review on hot tearing of magnesium alloys

    Directory of Open Access Journals (Sweden)

    Jiangfeng Song

    2016-09-01

    Full Text Available Hot tearing is often a major casting defect in magnesium alloys and has a significant impact on the quality of their casting products. Hot tearing of magnesium alloys is a complex solidification phenomenon which is still not fully understood, it is of great importance to investigate the hot tearing behaviour of magnesium alloys. This review attempts to summarize the investigations on hot tearing of magnesium alloys over the past decades. The hot tearing criteria including recently developed Kou's criterion are summarized and compared. The numeric simulation and assessing methods of hot tearing, factors influencing hot tearing, and hot tearing susceptibility (HTS of magnesium alloys are discussed.

  14. Biomedical coatings on magnesium alloys - a review.

    Science.gov (United States)

    Hornberger, H; Virtanen, S; Boccaccini, A R

    2012-07-01

    This review comprehensively covers research carried out in the field of degradable coatings on Mg and Mg alloys for biomedical applications. Several coating methods are discussed, which can be divided, based on the specific processing techniques used, into conversion and deposition coatings. The literature review revealed that in most cases coatings increase the corrosion resistance of Mg and Mg alloys. The critical factors determining coating performance, such as corrosion rate, surface chemistry, adhesion and coating morphology, are identified and discussed. The analysis of the literature showed that many studies have focused on calcium phosphate coatings produced either using conversion or deposition methods which were developed for orthopaedic applications. However, the control of phases and the formation of cracks still appear unsatisfactory. More research and development is needed in the case of biodegradable organic based coatings to generate reproducible and relevant data. In addition to biocompatibility, the mechanical properties of the coatings are also relevant, and the development of appropriate methods to study the corrosion process in detail and in the long term remains an important area of research. Copyright © 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  15. Nuclear Physics Review

    Energy Technology Data Exchange (ETDEWEB)

    Walker-Loud, Andre

    2014-11-01

    Anchoring low-energy nuclear physics to the fundamental theory of strong interactions remains an outstanding challenge. I review the current progress and challenges of the endeavor to use lattice QCD to bridge this connection. This is a particularly exciting time for this line of research as demonstrated by the spike in the number of different collaborative efforts focussed on this problem and presented at this conference. I first digress and discuss the 2013 Ken Wilson Award.

  16. Two main and a new type rare earth elements in Mg alloys: A review

    Science.gov (United States)

    Kong, Linghang

    2017-09-01

    Magnesium (Mg) alloys stand for the lightest structure engineering materials. Moreover, the strengthening of Mg alloys in ductility, toughness and corrosion predominates their wide applications. With adding rare earth elements in Mg, the mechanical properties will be improved remarkably, especially their plasticity and strength. A brief overview of the addition of rare earth elements for Mg alloys is shown. The basic mechanisms of strengthening Mg alloys with rare earth elements are reviewed, including the solid solution strengthening, grain refinement and long period stacking ordered (LPSO) phase. Furthermore, the available rare earth elements are summarized by type, chemical or physical effects and other unique properties. Finally, some challenge problems that the research is facing and future expectations of ra-re-earth Mg alloys are stated and discussed.

  17. High temperature strain of metals and alloys. Physical fundamentals

    Energy Technology Data Exchange (ETDEWEB)

    Levitin, V. [National Technical Univ., Zaporozhye (Ukraine)

    2006-07-01

    The author shows how new in-situ X-ray investigations and transmission electron microscope studies lead to novel explanations of high-temperature deformation and creep in pure metals, solid solutions and super alloys. This approach is the first to find unequivocal and quantitative expressions for the macroscopic deformation rate by means of three groups of parameters: substructural characteristics, physical material constants and external conditions. Creep strength of the studied uptodate single crystal super alloys is greatly increased over conventional polycrystalline super alloys. The contents of this book include: macroscopic characteristics of strain at high temperatures; experimental equipment and technique of in situ X-ray investigations; experimental data and structural parameters in deformed metals; sub-boundaries as dislocation sources and obstacles; the physical mechanism of creep and the quantitative structural model; simulation of the parameters evolution; system of differential equations; high-temperature deformation of industrial super alloys; single crystals of super alloys; effect of composition, orientation and temperature on properties; and creep of some refractory metals.

  18. The physical metallurgy of mechanically-alloyed, dispersion-strengthened Al-Li-Mg and Al-Li-Cu alloys

    Science.gov (United States)

    Gilman, P. S.

    1984-01-01

    Powder processing of Al-Li-Mg and Al-Li-Cu alloys by mechanical alloying (MA) is described, with a discussion of physical and mechanical properties of early experimental alloys of these compositions. The experimental samples were mechanically alloyed in a Szegvari attritor, extruded at 343 and 427 C, and some were solution-treated at 520 and 566 C and naturally, as well as artificially, aged at 170, 190, and 210 C for times of up to 1000 hours. All alloys exhibited maximum hardness after being aged at 170 C; lower hardness corresponds to the solution treatment at 566 C than to that at 520 C. A comparison with ingot metallurgy alloys of the same composition shows the MA material to be stronger and more ductile. It is also noted that properly aged MA alloys can develop a better combination of yield strength and notched toughness at lower alloying levels.

  19. Review of tantalum and niobium alloy production

    International Nuclear Information System (INIS)

    Buckman, R.W. Jr.

    1984-01-01

    This paper concentrates on the current state of niobium- and tantalum-base alloy production. The materials requirements, alloy compositions of interest, and production status are discussed. Finally, a list of developments needed to support the SP-100 program will be identified. A bibliography is included

  20. Irradiation growth in zirconium alloys: a review

    International Nuclear Information System (INIS)

    Fidleris, V.

    1980-09-01

    The change in shape during irradiation without external stress, irradiation growth, was first discovered in uranium and later in graphite, zirconium and other core materials which exhibit anisotropic physical properties. The direction of maximum growth of metals invariably corresponds with the direction of minimum thermal expansion. In polycrystalline zirconium alloys growth is positive in the direction of maximum deformation during fabrication and in other directions it can be either positive or negative depending on the preferred orientation of grains (crystallographic texture). Growth increases gradually with temperature between 300 K and 620 K and rapidly with fluence up to about 1 x 10 25 n.m. -2 (Eμ1 MeV). At higher fluences the growth appears to saturate in annealed materials and reach a steady rate approximately proportional to dislocation density in cold-worked materials. Above 600 K both annealed and cold-worked materials have similar steady growth rates. Irradiation growth is caused by the segregation to different sinks of the vacancies and interstitials generated by irradiation, but the dominant types of sinks for each type of point defect and the mode of transport of the point defects to sinks cannot therefore be predicted theoretically. For the purpose of designing reactor core components empirical equations have been derived that can satisfactorily predict the steady state growth behaviour from texture and microstructure. (auth)

  1. Efimov physics: a review

    Science.gov (United States)

    Naidon, Pascal; Endo, Shimpei

    2017-05-01

    This article reviews theoretical and experimental advances in Efimov physics, an array of quantum few-body and many-body phenomena arising for particles interacting via short-range resonant interactions, that is based on the appearance of a scale-invariant three-body attraction theoretically discovered by Vitaly Efimov in 1970. This three-body effect was originally proposed to explain the binding of nuclei such as the triton and the Hoyle state of carbon-12, and later considered as a simple explanation for the existence of some halo nuclei. It was subsequently evidenced in trapped ultra-cold atomic clouds and in diffracted molecular beams of gaseous helium. These experiments revealed that the previously undetermined three-body parameter introduced in the Efimov theory to stabilise the three-body attraction typically scales with the range of atomic interactions. The few- and many-body consequences of the Efimov attraction have been since investigated theoretically, and are expected to be observed in a broader spectrum of physical systems.

  2. Statistical physics of multicomponent alloys using KKR-CPA

    Science.gov (United States)

    Khan, Suffian N.; Staunton, J. B.; Stocks, G. M.

    2016-02-01

    We apply variational principles from statistical physics and the Landau theory of phase transitions to multicomponent alloys using the multiple-scattering theory of Korringa-Kohn-Rostoker (KKR) and the coherent potential approximation (CPA). This theory is a multicomponent generalization of the S(2 ) theory of binary alloys developed by G. M. Stocks, J. B. Staunton, D. D. Johnson, and others. It is highly relevant to the chemical phase stability of high-entropy alloys as it predicts the kind and size of finite-temperature chemical fluctuations. In doing so, it includes effects of rearranging charge and other electronics due to changing site occupancies. When chemical fluctuations grow without bound, an absolute instability occurs and a second-order order-disorder phase transition may be inferred. The S(2 ) theory is predicated on the fluctuation-dissipation theorem; thus we derive the linear response of the CPA medium to perturbations in site-dependent chemical potentials in great detail. The theory lends itself to a natural interpretation in terms of competing effects: entropy driving disorder and favorable pair interactions driving atomic ordering. To further clarify interpretation, we present results for representative ternary alloys CuAgAu, NiPdPt, RhPdAg, and CoNiCu within a frozen charge (or band-only) approximation. These results include the so-called Onsager mean-field correction that extends the temperature range for which the theory is valid.

  3. Effect of hydrogen on aluminium and aluminium alloys: A review

    DEFF Research Database (Denmark)

    Ambat, Rajan; Dwarakadasa, E.S.

    1996-01-01

    Susceptibility of aluminium and its alloys towards hydrogen embrittlement has been well established. Still a lot of confusion exists on the question of transport of hydrogen and its possible role in stress corrosion cracking. This paper reviews some of the fundamental properties of hydrogen...... in aluminium and its alloys and its effect on mechanical properties. The importance of hydrogen embrittlement over anodic dissolution to explain the stress corrosion cracking mechanism of these alloys is also examined in considerable detail. The various experimental findings concerning the link between...... hydrogen embrittlement and stress corrosion cracking are also discussed....

  4. A Review of Undergraduate Physics

    Science.gov (United States)

    Bayman, Benjamin F.; Hamermesh, Morton

    1986-02-01

    A study aid for senior and graduate level students needing a review of undergraduate physics. Covers a broad range of topics, with carefully worked examples illustrating important problem-solving methods. A collection of self-test problems helps students prepare for the College Entrance Advanced Physics Examination and the Qualifying Written Examination for the PhD.

  5. BOOK REVIEW: Complete Physics

    Science.gov (United States)

    Carson, Simon

    2000-03-01

    This book contains all the essential concepts for GCSE (or equivalent) physics courses or for general science courses at Key Stage 4. It claims to be ideal for use as a bridging resource for those intending to take physics beyond GCSE: it is no surprise, then, that the book is written at a level above that of the average Key Stage 4 student. It includes material not included in many GCSE syllabuses; this is clearly identified in the contents pages. It would be a useful resource for more able students at GCSE or for beginning A-level students. The layout of the book is attractive. It is well illustrated and colourful. Some of the illustrations are striking: each of the 12 main sections of the book begins with a title page that includes some unusual photographs illustrating physical ideas. Section 2, Forces and Motion, has a photograph of a bungee jumper leaping from the Sky Tower in New Zealand, taken at night looking along the length of the tower from its foot. Section 9, Magnets and Currents, has a computer-generated picture of the magnetic field in a fusion generator. These pictures, as well as contributing to the attractiveness of the book, could be used to initiate discussions of some of the physics. However, there are pictures that serve little useful purpose: a photograph of a recording station for seismic waves looks like any other building lit up at night. A photograph of a rock band in the middle of a section on sound carries no explanatory caption at all and is purely decorative. Other illustrations - in a variety of styles - do illustrate some physical ideas very well: the diagrams of motors and generators, for instance, are far clearer than my efforts on the blackboard! The book is divided into 14 sections with titles reflecting the traditional divisions of physics syllabuses, together with a beginning section on measurement and units and two final sections, `History of Key Ideas' and `Experimental Physics'. The first section, `Measurement and Units

  6. A Review of Dissimilar Welding Techniques for Magnesium Alloys to Aluminum Alloys

    Science.gov (United States)

    Liu, Liming; Ren, Daxin; Liu, Fei

    2014-01-01

    Welding of dissimilar magnesium alloys and aluminum alloys is an important issue because of their increasing applications in industries. In this document, the research and progress of a variety of welding techniques for joining dissimilar Mg alloys and Al alloys are reviewed from different perspectives. Welding of dissimilar Mg and Al is challenging due to the formation of brittle intermetallic compound (IMC) such as Mg17Al12 and Mg2Al3. In order to increase the joint strength, three main research approaches were used to eliminate or reduce the Mg-Al intermetallic reaction layer. First, solid state welding techniques which have a low welding temperature were used to reduce the IMCs. Second, IMC variety and distribution were controlled to avoid the degradation of the joining strength in fusion welding. Third, techniques which have relatively controllable reaction time and energy were used to eliminate the IMCs. Some important processing parameters and their effects on weld quality are discussed, and the microstructure and metallurgical reaction are described. Mechanical properties of welds such as hardness, tensile, shear and fatigue strength are discussed. The aim of the report is to review the recent progress in the welding of dissimilar Mg and Al to provide a basis for follow-up research. PMID:28788646

  7. A Review of Dissimilar Welding Techniques for Magnesium Alloys to Aluminum Alloys

    Directory of Open Access Journals (Sweden)

    Liming Liu

    2014-05-01

    Full Text Available Welding of dissimilar magnesium alloys and aluminum alloys is an important issue because of their increasing applications in industries. In this document, the research and progress of a variety of welding techniques for joining dissimilar Mg alloys and Al alloys are reviewed from different perspectives. Welding of dissimilar Mg and Al is challenging due to the formation of brittle intermetallic compound (IMC such as Mg17Al12 and Mg2Al3. In order to increase the joint strength, three main research approaches were used to eliminate or reduce the Mg-Al intermetallic reaction layer. First, solid state welding techniques which have a low welding temperature were used to reduce the IMCs. Second, IMC variety and distribution were controlled to avoid the degradation of the joining strength in fusion welding. Third, techniques which have relatively controllable reaction time and energy were used to eliminate the IMCs. Some important processing parameters and their effects on weld quality are discussed, and the microstructure and metallurgical reaction are described. Mechanical properties of welds such as hardness, tensile, shear and fatigue strength are discussed. The aim of the report is to review the recent progress in the welding of dissimilar Mg and Al to provide a basis for follow-up research.

  8. Corrosion-Resistant High-Entropy Alloys: A Review

    Directory of Open Access Journals (Sweden)

    Yunzhu Shi

    2017-02-01

    Full Text Available Corrosion destroys more than three percent of the world’s gross domestic product. Therefore, the design of highly corrosion-resistant materials is urgently needed. By breaking the classical alloy-design philosophy, high-entropy alloys (HEAs possess unique microstructures, which are solid solutions with random arrangements of multiple elements. The particular locally-disordered chemical environment is expected to lead to unique corrosion-resistant properties. In this review, the studies of the corrosion-resistant HEAs during the last decade are summarized. The corrosion-resistant properties of HEAs in various aqueous environments and the corrosion behavior of HEA coatings are presented. The effects of environments, alloying elements, and processing methods on the corrosion resistance are analyzed in detail. Furthermore, the possible directions of future work regarding the corrosion behavior of HEAs are suggested.

  9. Application of Shape Memory Alloys in Seismic Isolation: A Review

    Directory of Open Access Journals (Sweden)

    Shaghayegh Alvandi

    2014-12-01

    Full Text Available In the last two decades, there has been an increasing interest in structural engineering control methods. Shape memory alloys and seismic isolation systems are examples of passive control systems that use of any one alone, effectively improve the seismic performance of the structure. Characteristics such as large strain range without any residual deformation, high damping capacity, excellent re-centering, high resistance to fatigue and corrosion and durability have made shape memory alloy an effective damping device or part of base isolators. A unique characteristic of shape memory alloys is in recovering residual deformations even after strong ground excitations. Seismic isolation is a device to lessen earthquake damage prospects. In the latest research studies, shape memory alloy is utilized in combination with seismic isolation system and their results indicate the effectiveness of the application of them to control the response of the structures. This paper reviews the findings of research studies on base isolation system implemented in the building and/or bridge structures by including the unique behavior of shape memory alloys. This study includes the primary information about the characteristic of the isolation system as well as the shape memory material. The efficiency and feasibility of the two mechanisms are also presented by few cases in point.

  10. Nitriding of super alloys for enhancing physical properties

    Science.gov (United States)

    Purohit, A.

    1984-06-25

    The invention teaches the improvement of certain super alloys by exposing the alloy to an atmosphere of elemental nitrogen at elevated temperatures in excess of 750/sup 0/C but less than 1150/sup 0/C for an extended duration, viz., by nitriding the surface of the alloy, to establish barrier nitrides of the order of 25 to 100 micrometers thickness. These barrier

  11. The effect of selected alloying element additions on properties of Mg-based alloy as bioimplants: A literature review

    Science.gov (United States)

    Zhang, Li-Nan; Hou, Zeng-Tao; Ye, Xin; Xu, Zhao-Bin; Bai, Xue-Ling; Shang, Peng

    2013-09-01

    This review investigates the current application limitations of Mg and Mg alloys. The key issues hindering the application of biodegradable Mg alloys as implants are their fast degradation rate and biological consideration. We have discussed the effect of some selected alloying element additions on the properties of the Mg-based alloy, especially the nutrient elements in human (Zn, Mn, Ca, Sr). Different grain sizes, phase constituents and distributions consequently influence the mechanical properties of the Mg alloys. Solution strengthening and precipitation strengthening are enhanced by the addition of alloying elements, generally improving the mechanical properties. Besides, the hot working process can also improve the mechanical properties. Combination of different processing steps is suggested to be adopted in the fabrication of Mg-based alloys. Corrosion properties of these Mg-based alloys have been measured in vitro and in vivo. The degradation mechanism is also discussed in terms of corrosion types, rates, byproducts and response of the surrounding tissues. Moreover, the clinical response and requirements of degradable implants are presented, especially for the nutrient elements (Ca, Mn, Zn, Sr). This review provides information related to different Mg alloying elements and presents the promising candidates for an ideal implant.

  12. A critical review of high entropy alloys and related concepts

    International Nuclear Information System (INIS)

    Miracle, D.B.; Senkov, O.N.

    2017-01-01

    High entropy alloys (HEAs) are barely 12 years old. The field has stimulated new ideas and has inspired the exploration of the vast composition space offered by multi-principal element alloys (MPEAs). Here we present a critical review of this field, with the intent of summarizing key findings, uncovering major trends and providing guidance for future efforts. Major themes in this assessment include definition of terms; thermodynamic analysis of complex, concentrated alloys (CCAs); taxonomy of current alloy families; microstructures; mechanical properties; potential applications; and future efforts. Based on detailed analyses, the following major results emerge. Although classical thermodynamic concepts are unchanged, trends in MPEAs can be different than in simpler alloys. Common thermodynamic perceptions can be misleading and new trends are described. From a strong focus on 3d transition metal alloys, there are now seven distinct CCA families. A new theme of designing alloy families by selecting elements to achieve a specific, intended purpose is starting to emerge. A comprehensive microstructural assessment is performed using three datasets: experimental data drawn from 408 different alloys and two computational datasets generated using the CALculated PHAse Diagram (CALPHAD) method. Each dataset emphasizes different elements and shows different microstructural trends. Trends in these three datasets are all predicted by a ‘structure in – structure out’ (SISO) analysis developed here that uses the weighted fractions of the constituent element crystal structures in each dataset. A total of 13 distinct multi-principal element single-phase fields are found in this microstructural assessment. Relationships between composition, microstructure and properties are established for 3d transition metal MPEAs, including the roles of Al, Cr and Cu. Critical evaluation shows that commercial austenitic stainless steels and nickel alloys with 3 or more principal elements are

  13. Insight of magnesium alloys and composites for orthopedic implant applications – a review

    Directory of Open Access Journals (Sweden)

    R Radha

    2017-09-01

    Full Text Available Magnesium (Mg and its alloys have been widely researched for orthopedic applications recently. Mg alloys have stupendous advantages over the commercially available stainless steel, Co-Cr-Ni alloy and titanium implants. Till date, extensive mechanical, in-vitro and in-vivo studies have been done to improve the biomedical performance of Mg alloys through alloying, processing conditions, surface modification etc. This review comprehensively describes the strategies for improving the mechanical and degradation performance of Mg alloys through properly tailoring the composition of alloying elements, reinforcements and processing techniques. It also highlights the status and progress of research in to (i the selection of nutrient elements for alloying, reinforcement and its effects (ii type of Mg alloy system (binary, ternary and quaternary and composites (iii grain refinement for strengthening through severe plastic deformation techniques. Furthermore it also emphasizes on the importance of Mg composites with regard to hard tissue applications.

  14. B physics - a theoretical review

    International Nuclear Information System (INIS)

    Rosner, J.L.

    1998-01-01

    This overview of what we can hope to learn from high-statistics experiments in B physics in the next few years includes (a) a review of parameters of the Cabibbo-Kobayashi-Maskawa (CKM) matrix; (b) direct determination of magnitudes of CKM elements; (c) forthcoming information from studies of kaons; (d) CP violation in B decays; (e) aspects of rate measurements; (f) the role of charm-anticharm annihilation; (g) remarks on tagging; and (h) effects beyond the standard model. (orig.)

  15. Brief Review of Charm Physics

    CERN Document Server

    Gersabeck, Marco

    2012-01-01

    Charm physics has attracted increased attention after first evidence for charm mixing was observed in 2007. The level of attention has risen sharply after LHCb reported first evidence for CP violation in the charm sector. Neither mixing nor CP violation have been established by a single unambiguous measurement to date. This review covers the status of mixing and CP violation measurements and comments on the challenges on the road ahead, both on the experimental and theoretical side, and on ways to tackle them.

  16. The degradation of zirconium alloys in nuclear reactors - a review

    International Nuclear Information System (INIS)

    Lim, D.; Graham, N.A.

    1986-01-01

    This report presents the findings of a survey of available non-Canadian literature on the oxidation and hydriding of zirconium alloys. Much of the literature was found to address the Zircaloys, particularly when used as fuel cladding subjected to a radioactive and oxidizing environment. Hydriding of Zircaloys is mainly attributed to oxidation. The survey revealed that Zr-Nb alloys have been included in some investigations; however, data on the long-term degradation of Zr-2.5 wt% Nb, in particular, were scarce. The reviewed literature did not lead to conclusions regarding the potential for accelerated hydriding due to corrosion at crevices and/or second-phase particles, nor did it lead to conclusions as to the potential for a 'breakaway' in oxidation and hydrogen acquisition in long service life of Zr-Nb alloys. Specific information on service experience in U.S.S.R. power reactors could not be obtained; however, most of the information surveyed leads to the conclusion that fuel channels having Zr-2.5 wt% Nb pressure tubes should perform satisfactorily with respect to degradation from corrosion and hydriding provided they are installed correctly and are not operated under conditions that are far removed from those anticipated in design. 91 refs

  17. Physical Review: a family of journals

    Science.gov (United States)

    Sprouse, Gene

    2013-03-01

    The expansion of research in physics in the last 100 years has been reflected in the expansion of the Physical Review(PR). Reviews of Modern Physics was the first ``new'' journal, starting in 1929. Physical Review Letters commenced in 1958, and was the first ``letters'' type of journal for important new results in all fields. By 1970 the Physical Review itself had grown so large that it was necessary to separate it by field into manageable volumes: PRA, PRB, PRC and PRD, and subsequently PRE, which was split off from PRA. More recently, two Special Topics journals for accelerator physics and physics education were pioneers of the open access business model, and the newest member of the family, Physical Review X, continues this trend. PRX is broad scope and very selective, setting it well above many of the new open access journals with a review standard of ``not incorrect.'' Some possible future directions for the Physical Review journals will be discussed.

  18. A review of the structural characteristics of alloy 800

    International Nuclear Information System (INIS)

    Orr, J.

    1978-01-01

    The published literature is reviewed and supplemented by current information from the author's laboratory, to show the influence of various compositional, heat treatment and thermomechanical factors on the structural characteristics of Alloy 800. The features discussed include carbon, aluminium, titanium and boron, solution treatment, ageing treatments with and without applied strain, and cold working. Examples of the aspects reviewed include the effect of heat treatment and service or testing temperature on the austenite grain size, and the relative importance of M 23 C 6 and TiC, the influence of carbon level on gamma prime, the effect of residual or steady stress combined with time at temperature on changes in carbide or gamma prime morphology, and on the appearance of sigma or other intermetallic phases. The questions posed by these features are discussed generally, in terms of their effect on the mechanical properties at ambient and elevated temperatures and on the time-dependent properties. The review also suggests areas where further research work is required on Alloy 800. (Auth.)

  19. Thermo-physical Properties and Mechanical Properties of Burn-resistant Titanium Alloy Ti40

    Directory of Open Access Journals (Sweden)

    LAI Yunjin

    2017-10-01

    Full Text Available As a functional material of burn-resistant titanium alloy, the physical properties of Ti40 alloy were first reported. The chemical compositions of Ti40 alloy ingots by VAR were uniform. The microstructures of Ti40 alloy slab manufactured by HEFF+WPF were uniform. The results show that the room temperature tensile strength of Ti40 alloy is 950 MPa degree. The properties of high temperature heat exposure, creep resistance and lasting time are good at 500 ℃. In the range from room temperature to 600 ℃, Young's modulus and shear modulus are decreased linearly with increasing the temperature, Poisson's ratio is increases slowly as the temperature rises, and linear thermal expansion coefficient and average linear expansion coefficient is increase as the temperature rises.

  20. Biodegradation of Secondary Phase Particles in Magnesium Alloys: A Critical Review

    Energy Technology Data Exchange (ETDEWEB)

    Kannan, M. Bobby [James Cook University, Townsville (Australia)

    2016-04-15

    Magnesium alloys have been extensively studied in recent years for potential biodegradable implant applications. A great deal of work has been done on the evaluation of the corrosion behaviour of magnesium alloys under in vitro and in vivo conditions. However, magnesium alloys, in general, contain secondary phase particles distributed in the matrix and/or along the grain boundaries. Owing to their difference in chemistry in comparison with magnesium matrix, these particles may exhibit different corrosion behaviour. It is essential to understand the corrosion behaviour of secondary phase particles in magnesium alloys in physiological conditions for implant applications. This paper critically reviews the biodegradation behaviour of secondary phase particles in magnesium alloys.

  1. Physical mechanism of surface roughening on the radial core-shell nanowire heterostructure with alloy shell

    Science.gov (United States)

    Cao, Yuanyuan; Diao, Dongfeng

    2017-05-01

    We proposed a quantitative thermodynamic theory to address the physical process of surface roughening during the epitaxial growth of core-shell NW with alloy layer. The surface roughening origins from the transformation of the Frank-van der Merwe (FM) mode to the Stranski-Krastanow (SK) mode. In addition to the radius of NW core, the composition and thickness of alloy shell could determine the growth behaviors due to their modulation to the strain. The established theoretical model not only explains the surface roughening caused by the alloy shell layer, but also provides a new way to control the growth of core-shell NW.

  2. Physical mechanism of surface roughening on the radial core-shell nanowire heterostructure with alloy shell

    Directory of Open Access Journals (Sweden)

    Yuanyuan Cao

    2017-05-01

    Full Text Available We proposed a quantitative thermodynamic theory to address the physical process of surface roughening during the epitaxial growth of core-shell NW with alloy layer. The surface roughening origins from the transformation of the Frank-van der Merwe (FM mode to the Stranski-Krastanow (SK mode. In addition to the radius of NW core, the composition and thickness of alloy shell could determine the growth behaviors due to their modulation to the strain. The established theoretical model not only explains the surface roughening caused by the alloy shell layer, but also provides a new way to control the growth of core-shell NW.

  3. Finite Element Based Physical Chemical Modeling of Corrosion in Magnesium Alloys

    Directory of Open Access Journals (Sweden)

    Venkatesh Vijayaraghavan

    2017-03-01

    Full Text Available Magnesium alloys have found widespread applications in diverse fields such as aerospace, automotive, bio-medical and electronics industries due to its relatively high strength-to-weight ratio. However, stress corrosion cracking of these alloys severely restricts their applications in several novel technologies. Hence, it will be useful to identify the corrosion mechanics of magnesium alloys under external stresses as it can provide further insights on design of these alloys for critical applications. In the present study, the corrosion mechanics of a commonly used magnesium alloy, AZ31, is studied using finite element simulation with a modified constitutive material damage model. The data obtained from the finite element modeling were further used to formulate a mathematical model using computational intelligence algorithm. Sensitivity and parametric analysis of the derived model further corroborated the mechanical response of the alloy in line with the corrosion physics. The proposed approach is anticipated to be useful for materials engineers for optimizing the design criteria for magnesium alloys catered for high temperature applications.

  4. Review of Reactivity Experiments for Lithium Ternary Alloys

    Energy Technology Data Exchange (ETDEWEB)

    Jolodosky, A. [Univ. of California, Berkeley, CA (United States); Bolind, A. [Univ. of California, Berkeley, CA (United States); Fratoni, M. [Univ. of California, Berkeley, CA (United States)

    2015-09-28

    Lithium is often the preferred choice as breeder and coolant in fusion blankets as it offers high tritium breeding, excellent heat transfer and corrosion properties, and most importantly, it has very high tritium solubility and results in very low levels of tritium permeation throughout the facility infrastructure. However, lithium metal vigorously reacts with air and water and exacerbates plant safety concerns. Consequently, Lawrence Livermore National Laboratory (LLNL) is attempting to develop a lithium-based alloy—most likely a ternary alloy—which maintains the beneficial properties of lithium (e.g. high tritium breeding and solubility) while reducing overall flammability concerns for use in the blanket of an inertial fusion energy (IFE) power plant. The LLNL concept employs inertial confinement fusion (ICF) through the use of lasers aimed at an indirect-driven target composed of deuterium-tritium fuel. The fusion driver/target design implements the same physics currently experimented at the National Ignition Facility (NIF). The plant uses lithium in both the primary coolant and blanket; therefore, lithium related hazards are of primary concern. Reducing chemical reactivity is the primary motivation for the development of new lithium alloys, and it is therefore important to come up with proper ways to conduct experiments that can physically study this phenomenon. This paper will start to explore this area by outlining relevant past experiments conducted with lithium/air reactions and lithium/water reactions. Looking at what was done in the past will then give us a general idea of how we can setup our own experiments to test a variety of lithium alloys.

  5. Computational studies of physical properties of Nb-Si based alloys

    Energy Technology Data Exchange (ETDEWEB)

    Ouyang, Lizhi [Middle Tennessee State Univ., Murfreesboro, TN (United States)

    2015-04-16

    The overall goal is to provide physical properties data supplementing experiments for thermodynamic modeling and other simulations such as phase filed simulation for microstructure and continuum simulations for mechanical properties. These predictive computational modeling and simulations may yield insights that can be used to guide materials design, processing, and manufacture. Ultimately, they may lead to usable Nb-Si based alloy which could play an important role in current plight towards greener energy. The main objectives of the proposed projects are: (1) developing a first principles method based supercell approach for calculating thermodynamic and mechanic properties of ordered crystals and disordered lattices including solid solution; (2) application of the supercell approach to Nb-Si base alloy to compute physical properties data that can be used for thermodynamic modeling and other simulations to guide the optimal design of Nb-Si based alloy.

  6. Biodegradable magnesium alloys for orthopaedic applications: A review on corrosion, biocompatibility and surface modifications

    International Nuclear Information System (INIS)

    Agarwal, Sankalp; Curtin, James; Duffy, Brendan; Jaiswal, Swarna

    2016-01-01

    Magnesium (Mg) and its alloys have been extensively explored as potential biodegradable implant materials for orthopaedic applications (e.g. Fracture fixation). However, the rapid corrosion of Mg based alloys in physiological conditions has delayed their introduction for therapeutic applications to date. The present review focuses on corrosion, biocompatibility and surface modifications of biodegradable Mg alloys for orthopaedic applications. Initially, the corrosion behaviour of Mg alloys and the effect of alloying elements on corrosion and biocompatibility is discussed. Furthermore, the influence of polymeric deposit coatings, namely sol-gel, synthetic aliphatic polyesters and natural polymers on corrosion and biological performance of Mg and its alloy for orthopaedic applications are presented. It was found that inclusion of alloying elements such as Al, Mn, Ca, Zn and rare earth elements provides improved corrosion resistance to Mg alloys. It has been also observed that sol-gel and synthetic aliphatic polyesters based coatings exhibit improved corrosion resistance as compared to natural polymers, which has higher biocompatibility due to their biomimetic nature. It is concluded that, surface modification is a promising approach to improve the performance of Mg-based biomaterials for orthopaedic applications. - Highlights: • The Mg based alloys are promising candidates for orthopaedic applications. • The rapid corrosion of Mg can affect human cells, and causes infection and implant failure. • The various physiological factors and Mg alloying elements affect the corrosion and mechanical properties of implants. • The polymeric deposit coatings enhance the corrosion resistance and biocompatibility.

  7. The development of additive manufacturing technique for nickel-base alloys: A review

    Science.gov (United States)

    Zadi-Maad, Ahmad; Basuki, Arif

    2018-04-01

    Nickel-base alloys are an attractive alloy due to its excellent mechanical properties, a high resistance to creep deformation, corrosion, and oxidation. However, it is a hard task to control performance when casting or forging for this material. In recent years, additive manufacturing (AM) process has been implemented to replace the conventional directional solidification process for the production of nickel-base alloys. Due to its potentially lower cost and flexibility manufacturing process, AM is considered as a substitute technique for the existing. This paper provides a comprehensive review of the previous work related to the AM techniques for Ni-base alloys while highlighting current challenges and methods to solving them. The properties of conventionally manufactured Ni-base alloys are also compared with the AM fabricated alloys. The mechanical properties obtained from tension, hardness and fatigue test are included, along with discussions of the effect of post-treatment process. Recommendations for further work are also provided.

  8. Physical properites of O- and N-containing V-Cr-Ti alloys

    Energy Technology Data Exchange (ETDEWEB)

    Park, J.H.; Kupperman, D.; Park, E.T.; Dragel, G. [Argonne National Laboratory, Chicago, IL (United States)

    1996-04-01

    Incorporation of O in the surface of V-Ti-Cr alloys has been investigated in controlled environments at 550-750{degrees}C, and test were performed to determine the physical properties of V-Cr-Ti-O solid solutions. The amount of O in the alloys has been determined by weight change measurements. Microhardness was used to determine O depth profiles of the alloys. X-ray diffraction indicated a phase transformation from body-centered cubic (bcc) to tetragonal in the lattice that was highly stressed because of O incorporation. Back-scattered-electron images and electron-energy-dispersive spectra revealed Cr depletion near alloy grain boundaries. Elastic modulus and Vickers hardness increased in O-enriched V-Cr-Ti alloys. Hardening of the alloys results from O atoms on face-centered interstitial sites in the bcc sublattice and the formation of homogeneous oxide or nitride phases via internal oxidation or nitridation. The O,N-enriched surface region exhibited the extraordinarily high Vickers hardness of {approx}18 GPa (1800 kg/mm{sup 2}), a value that is typical of oxides nitrides, or carbides, or that is obtainable by ion-beam irradiation of metals.

  9. METHODS OF PHYSICAL MODELING OF HYDRODYNAMIC PROCESSES AT CASTING OF ALLOYS

    Directory of Open Access Journals (Sweden)

    V. Ju. Stetsenko

    2012-01-01

    Full Text Available The method of physical modeling of hydrodynamic processes of alloys molding is developed. It is shown that as a liquid it is necessary to use water and diethyl ether at molding of steel, silumins, tin-base bronzes and waterglycerine solutions.

  10. "Physical Review Letters" in the Classroom

    Science.gov (United States)

    Angiolillo, Paul J.; Lynch, Jonathan

    2010-01-01

    Ask any physicist what the preeminent journal in the field is, and I think the almost unanimous answer will be "Physical Review Letters" ("PRL"). This weekly journal of the American Physical Society publishes high-impact research from all the major subdisciplines of physics. This journal is not the one you would think is the first place a high…

  11. Aluminium. II - A review of deformation properties of high purity aluminium and dilute aluminium alloys.

    Science.gov (United States)

    Reed, R. P.

    1972-01-01

    The elastic and plastic deformation behavior of high-purity aluminum and of dilute aluminum alloys is reviewed. Reliable property data, including elastic moduli, elastic coefficients, tensile, creep, fatigue, hardness, and impact are presented. Single crystal tensile results are discussed. Rather comprehensive reference lists, containing publications of the past 20 years, are included for each of the above categories. Defect structures and mechanisms responsible for mechanical behavior are presented. Strengthening techniques (alloys, cold work, irradiation, quenching, composites) and recovery are briefly reviewed.

  12. Fatigue crack initiation of magnesium alloys under elastic stress amplitudes: A review

    Science.gov (United States)

    Wang, B. J.; Xu, D. K.; Wang, S. D.; Han, E. H.

    2017-12-01

    The most advantageous property of magnesium (Mg) alloys is their density, which is lower compared with traditional metallic materials. Mg alloys, considered the lightest metallic structural material among others, have great potential for applications as secondary load components in the transportation and aerospace industries. The fatigue evaluation of Mg alloys under elastic stress amplitudes is very important in ensuring their service safety and reliability. Given their hexagonal close packed structure, the fatigue crack initiation of Mg and its alloys is closely related to the deformation mechanisms of twinning and basal slips. However, for Mg alloys with shrinkage porosities and inclusions, fatigue cracks will preferentially initiate at these defects, remarkably reducing the fatigue lifetime. In this paper, some fundamental aspects about the fatigue crack initiation mechanisms of Mg alloys are reviewed, including the 3 followings: 1) Fatigue crack initiation of as-cast Mg alloys, 2) influence of microstructure on fatigue crack initiation of wrought Mg alloys, and 3) the effect of heat treatment on fatigue initiation mechanisms. Moreover, some unresolved issues and future target on the fatigue crack initiation mechanism of Mg alloys are also described.

  13. Physical and Mechanical Properties of LoVAR: A New Lightweight Particle-Reinforced Fe-36Ni Alloy

    Science.gov (United States)

    Stephenson, Timothy; Tricker, David; Tarrant, Andrew; Michel, Robert; Clune, Jason

    2015-01-01

    Fe-36Ni is an alloy of choice for low thermal expansion coefficient (CTE) for optical, instrument and electrical applications in particular where dimensional stability is critical. This paper outlines the development of a particle-reinforced Fe-36Ni alloy that offers reduced density and lower CTE compared to the matrix alloy. A summary of processing capability will be given relating the composition and microstructure to mechanical and physical properties.

  14. Review about laser nitriding of titanium alloys; Revision sobre nitruraciones laser de aleaciones de titanio

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Artieda, M.G.; Fernandez-Carrasquilla, J.

    2010-07-01

    A common technique used to improve the wear response of titanium alloys is to nitride the surface, using chemical or physical vapour deposition, ion implantation or surface remelting in a nitrogen atmosphere. In this revision nitriding systems with laser technology are studied, used in titanium alloys surface treatments.For high temperature, high strength applications, titanium based alloys are an attractive light-weight alternative to steel, due to their high strength to weight ratio and corrosion resistance. In applications that require good wear resistance, titanium alloys pose a problem due to their poor tribological characteristics.Titanium alloys used with a suitable nitriding treatment could allow the replacement of steel in different applications, obtaining weight savings in fabricated components. (Author). 68 refs.

  15. The Eleventh International Ural Seminar Radiation damage physics of metals and alloys. Abstracts

    International Nuclear Information System (INIS)

    2015-01-01

    The book includes abstracts of the Eleventh International Ural Seminar Radiation damage physics of metals and alloys (Kyshtym, 23 February - 1 March, 2015). General issues of radiation damage physics of metals and alloys are discussed. Materials for nuclear and thermonuclear power engineering, new approaches to the development of radiation-resistant structural steels are in the view of participants. The new trends in the physics of strongly correlated d- and f-electron systems, radiation technologies for creating materials with desired properties are considered. Much attention is paid to the impact of external influences on the structural and phase changes in the actinides, areas related with the study of radiation effects in dielectrics and semiconductors, the development of new devices and techniques for carrying out experiments. During the seminar the traditional School of the young speaker is held [ru

  16. A review of ordering phenomena in iron-silicon alloys

    Directory of Open Access Journals (Sweden)

    González, F.

    2013-06-01

    Full Text Available Silicon steel is an industrially-desired alloy of iron and silicon, characterised by soft magnetic properties, low eddy-current losses, and low magnetostriction. Silicon steels have narrow hysteresis cycles, making them particularly advantageous in applications using electromagnetic fields, such as transformers, generators, electric motor cores, and few other components in industry. Despite its incontestable industrial value, there is not much agreement on the atomic structure of silicon steel. Gaining better understanding of e.g. ordering processes in Fe-Si alloys could not only explain their magnetic properties, but also open opportunities to reduce their weaker characteristics, such as brittleness that adversely affects silicon steel workability and its associated high production costs. This review summarises the state-of-the-art knowledge about ordering in silicon steel and describes the most relevant experimental techniques used for studying its microstructure. In addition, the process of building the iron rich part of the Fe-Si phase diagram is explained. Lastly, the influence of order on the alloy’s magnetic and mechanical properties is illustrated.El acero al silicio es una aleación de importancia industrial, caracterizada por propiedades magnéticas blandas, bajas pérdidas por corrientes de Foucault y baja magnetostricción. Los aceros al silicio tienen ciclo de histéresis estrecho, lo que es una ventaja en aplicaciones con campos electromagnéticos, como transformadores, generadores, núcleos de motores eléctricos y otros componentes industriales. A pesar de su incomparable valor industrial, no hay convenio sobre la estructura atómica del acero al silicio. Obtener mayor conocimiento sobre los procesos de orden no sólo podría explicar las propiedades magnéticas sino que también podría abrir vías para la reducción de sus características más débiles, como su fragilidad, la cual afecta negativamente a la fabricación del

  17. Book review: Physics of tsunamis

    Science.gov (United States)

    Geist, Eric L.

    2017-01-01

    Physics of Tsunamis”, second edition, provides a comprehensive analytical treatment of the hydrodynamics associated with the tsunami generation process. The book consists of seven chapters covering 388 pages. Because the subject matter within each chapter is distinct, an abstract appears at the beginning and references appear at the end of each chapter, rather than at the end of the book. Various topics of tsunami physics are examined largely from a theoretical perspective, although there is little information on how the physical descriptions are applied in numerical models.“Physics of Tsunamis”, by B. W. Levin and M. A. Nosov, Second Edition, Springer, 2016; ISBN-10: 33-1933106X, ISBN-13: 978-331933-1065

  18. Physical chemistry of the chlorination reactions of metals and alloys

    International Nuclear Information System (INIS)

    De Micco, Georgina

    2007-01-01

    This thesis has contributed towards the knowledge of complex systems.The chlorination reactions are non-catalytic solid-gas heterogeneous reactions which, in addition to the difficulties associated with the reactions occurring in an interface, have the particular features of chlorides compounds and their interactions.The questions arising from this type of study can not be solved by the application of an individual analysis technique.From the experimental point of view it is complicated, and many instrumental techniques need to be applied in order to obtain significant results as well as meaningful interpretations.The system under study is the chlorination of ternary and binary alloys containing Al, Cu and Zn and the pure metals, as these elements belong to the spent nuclear fuel cladding.The aim of the research has been to develop a process that eliminates most of the aluminium, which is the more abundant specie. In this way, the amount of material to be conditioned (vitrified) is reduced.The objectives proposed for each system have been achieved, and the results obtained can also be applied to similar systems for metal recycling [es

  19. Effect of chromium and phosphorus on the physical properties of iron and titanium-based amorphous metallic alloy films

    Science.gov (United States)

    Distefano, S.; Rameshan, R.; Fitzgerald, D. J.

    1991-01-01

    Amorphous iron and titanium-based alloys containing various amounts of chromium, phosphorus, and boron exhibit high corrosion resistance. Some physical properties of Fe and Ti-based metallic alloy films deposited on a glass substrate by a dc-magnetron sputtering technique are reported. The films were characterized using differential scanning calorimetry, stress analysis, SEM, XRD, SIMS, electron microprobe, and potentiodynamic polarization techniques.

  20. Physics with polarized beams: experimental review

    International Nuclear Information System (INIS)

    Krisch, A.D.

    1978-01-01

    In high energy physics, discussion of spin effects generally involves proton--proton scattering, that being the area where the best experiments could be performed. Several such experiments are reviewed

  1. Biodegradable magnesium alloys for orthopaedic applications: A review on corrosion, biocompatibility and surface modifications.

    Science.gov (United States)

    Agarwal, Sankalp; Curtin, James; Duffy, Brendan; Jaiswal, Swarna

    2016-11-01

    Magnesium (Mg) and its alloys have been extensively explored as potential biodegradable implant materials for orthopaedic applications (e.g. Fracture fixation). However, the rapid corrosion of Mg based alloys in physiological conditions has delayed their introduction for therapeutic applications to date. The present review focuses on corrosion, biocompatibility and surface modifications of biodegradable Mg alloys for orthopaedic applications. Initially, the corrosion behaviour of Mg alloys and the effect of alloying elements on corrosion and biocompatibility is discussed. Furthermore, the influence of polymeric deposit coatings, namely sol-gel, synthetic aliphatic polyesters and natural polymers on corrosion and biological performance of Mg and its alloy for orthopaedic applications are presented. It was found that inclusion of alloying elements such as Al, Mn, Ca, Zn and rare earth elements provides improved corrosion resistance to Mg alloys. It has been also observed that sol-gel and synthetic aliphatic polyesters based coatings exhibit improved corrosion resistance as compared to natural polymers, which has higher biocompatibility due to their biomimetic nature. It is concluded that, surface modification is a promising approach to improve the performance of Mg-based biomaterials for orthopaedic applications. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Recent advances in alloy counter electrodes for dye-sensitized solar cells. A critical review

    International Nuclear Information System (INIS)

    Tang, Qunwei; Duan, Jialong; Duan, Yanyan; He, Benlin; Yu, Liangmin

    2015-01-01

    Highlights: • Recent advances on alloy CEs for DSSCs are reviewed. • Pt-free CEs with nonmetal species suffer from structure deviation or collapse at cell operation. • Alloyed CEs exhibit enhanced catalytic activity for triiodide reduction. • Alloyed CEs display enhanced dissolution resistance in liquid electrolyte. - Abstract: Dye-sensitized solar cell (DSSC) has been considered as a potentially cost-effective alternative to silicon solar cell. By optimizing three components of a typical DSSC including a dye-sensitized wide-bandgap semiconductor photoanode for creating and transporting electrons, n redox electrolyte, and a counter electrode (CE) for reducing oxidized species in electrolyte, a maximum power conversion efficiency of 13% has been determined. The high cost of DSSCs is to a large part dictated by the high loading of Pt required to catalyze the triiodide reduction reaction. Arguably one of the arising routes to reduce fabrication cost of DSSCs with no sacrifice of catalytic activity of CEs is to alloy Pt with other metals/nonmetals or to replace Pt with Pt-free alloys. In this perspective paper, we outline the advances of alloy CEs in comparison with other alternatives such as carbonaceous materials and conductive polymers and their hybrids including design concepts, fabrication approaches, and properties. Finally, this review launches prospects and challenges of promising alloy CEs for their applications in high-efficiency DSSCs.

  3. Current research progress in grain refinement of cast magnesium alloys: A review article

    International Nuclear Information System (INIS)

    Ali, Yahia; Qiu, Dong; Jiang, Bin; Pan, Fusheng; Zhang, Ming-Xing

    2015-01-01

    Grain refinement of cast magnesium alloys, particularly in magnesium–aluminium (Mg–Al) based alloys, has been an active research topic in the past two decades, because it has been considered as one of the most effective approaches to simultaneously increase the strength, ductility and formability. The development of new grain refiners was normally based on the theories/models that were established through comprehensive and considerable studies of grain refinement in cast Al alloys. Generally, grain refinement in cast Al can be achieved through either inoculation treatment, which is a process of adding, or in situ forming, foreign particles to promote heterogeneous nucleation rate, or restricting grain growth by controlling the constitutional supercooling or both. But, the concrete and tangible grain refinement mechanism in cast metals is still not fully understood and there are a number of controversies. Therefore, most of the new developed grain refiners for Mg–Al based alloys are not as efficient as the commercially available ones, such as zirconium in non-Al containing Mg alloys. To facilitate the research in grain refinement of cast magnesium alloys, this review starts with highlighting the theoretical aspects of grain refinement in cast metals, followed by reviewing the latest research progress in grain refinement of magnesium alloys in terms of the solute effect and potent nucleants

  4. Influence of recasting on the quality of dental alloys: A systematic review.

    Science.gov (United States)

    Vaillant-Corroy, Anne-Sophie; Corne, Pascale; De March, Pascal; Fleutot, Solenne; Cleymand, Franck

    2015-08-01

    Dental alloy manufacturers advise against the reuse of previously melted alloy. However, for economic reasons, dental laboratories often reuse the casting surplus (sprue and metal remaining in the crucible former). Such reuse remains a controversial topic in dental practice. The purpose of this systematic review was to assess the effects of remelting dental alloys by evaluating the following parameters: reasons for recasting and associated processes, feasible number of recastings, treatment of alloys before recasting and its effects on cytotoxicity, color of opaque porcelain, castability of alloys, marginal accuracy, mechanical properties, porcelain-metal interfaces, and corrosion. The systematic review included all studies on dental alloy recasting. MEDLINE, Dentistry and Oral Science Source, Science Direct, and ISI Web of Science were searched (up to July 2014). Data were extracted and the quality of studies was assessed. Thirty-four studies published between 1983 and 2014 were included. The number of recastings ranged from 1 to 10. The percentage of new alloy ranged from 0 to 100 wt%, although the mean value was 50 wt%. Evidence for the feasibility of adding 50% new metal at each recasting is limited. The number of recastings should be limited to a maximum of 4. No general test protocol can be deduced from these studies, which limits the comparison and exploitation of data. Furthermore, no consensus protocol exists for the evaluation of recasting. Future studies should work toward establishing a standard protocol. Copyright © 2015 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  5. Physical Properties of C-Si Alloys in C2/m Structure

    Science.gov (United States)

    Wang, Qian-Kun; Chai, Chang-Chun; Fan, Qing-Yang; Yang, Yin-Tang

    2017-08-01

    Using the first principles calculations based on density functional theory, the crystal structure, elastic anisotropy, and electronic properties of carbon, silicon and their alloys (C 12 Si 4, C 8 Si 8, and C 4 Si 12 ) in a monoclinic structure (C2/m) are investigated. The calculated results such as lattice parameters, elastic constants, bulk modulus, and shear modulus of C 16 and Si 16 in C2/m structure are in good accord with previous work. The elastic constants show that C 16, Si 16, and their alloys in C2/m structure are mechanically stable. The calculated results of universal anisotropy index, compression and shear anisotropy percent factors indicate that C-Si alloys present elastic anisotropy, and C 8 Si 8 shows a greater anisotropy. The Poisson’s ratio and the B/G value show that C 8 Si 8 is ductile material and other four C-Si alloys are brittle materials. In addition, Debye temperature and average sound velocity are predicted utilizing elastic modulus and density of C-Si alloys. The band structure and the partial density of states imply that C 16 and Si 16 are indirect band gap semiconductors, while C 12 Si 4, C 8 Si 8, and C 4 Si 12 are semi-metallic alloys. Supported by the Natural Science Foundation of China under Grant No. 61474089, Open Fund of Key Laboratory of Complex Electromagnetic Environment Science and Technology, China Academy of Engineering Physics under Grant No. 2015-0214. YY.K

  6. Attitude Research in Physical Education: A Review

    Science.gov (United States)

    Silverman, Stephen

    2017-01-01

    This paper provides a comprehensive review of attitude research in physical education. The first section reviews theoretical models that are prevalent in attitude research. Then, the next section describes the methods that were used to locate the research used in the remainder of the paper. The third section discusses measurement issues in…

  7. Influence of Molybdenum on the Alloying and Physical Properties of Fe-Al

    Czech Academy of Sciences Publication Activity Database

    Jirásková, Yvonna; Buršík, Jiří; Hapla, Miroslav; Turek, Ilja

    2015-01-01

    Roč. 28, č. 3 (2015), s. 905-910 ISSN 1557-1939 R&D Projects: GA ČR(CZ) GAP108/11/1350; GA MŠk(CZ) ED1.1.00/02.0068 Institutional support: RVO:68081723 Keywords : Nanostructured materials * Mechanical alloying * Magnetic proprties * Grain core * Defects Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.100, year: 2015

  8. Microstructure and physical properties of mechanically alloyed Fe-Mo powder

    Czech Academy of Sciences Publication Activity Database

    Jirásková, Yvonna; Zábranský, Karel; Turek, Ilja; Buršík, Jiří; Jančík, D.

    2009-01-01

    Roč. 477, - (2009), s. 55-61 ISSN 0925-8388 R&D Projects: GA ČR GA202/05/2111; GA ČR GD106/05/H008 Institutional research plan: CEZ:AV0Z20410507 Keywords : Nanostructured materials * Mechanical alloying * Microstructure * Magnetic measurements * Mössbauer spectroscopy Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.135, year: 2009

  9. Electrochemical and Optical Properties of Magnesium-Alloy Hydrides Reviewed

    Directory of Open Access Journals (Sweden)

    Thirugnasambandam G. Manivasagam

    2012-10-01

    Full Text Available As potential hydrogen storage media, magnesium based hydrides have been systematically studied in order to improve reversibility, storage capacity, kinetics and thermodynamics. The present article deals with the electrochemical and optical properties of Mg alloy hydrides. Electrochemical hydrogenation, compared to conventional gas phase hydrogen loading, provides precise control with only moderate reaction conditions. Interestingly, the alloy composition determines the crystallographic nature of the metal-hydride: a structural change is induced from rutile to fluorite at 80 at.% of Mg in Mg-TM alloy, with ensuing improved hydrogen mobility and storage capacity. So far, 6 wt.% (equivalent to 1600 mAh/g of reversibly stored hydrogen in MgyTM(1-yHx (TM: Sc, Ti has been reported. Thin film forms of these metal-hydrides reveal interesting electrochromic properties as a function of hydrogen content. Optical switching occurs during (dehydrogenation between the reflective metal and the transparent metal hydride states. The chronological sequence of the optical improvements in optically active metal hydrides starts with the rare earth systems (YHx, followed by Mg rare earth alloy hydrides (MgyGd(1-yHx and concludes with Mg transition metal hydrides (MgyTM(1-yHx. In-situ optical characterization of gradient thin films during (dehydrogenation, denoted as hydrogenography, enables the monitoring of alloy composition gradients simultaneously.

  10. Fabrication, magnetostriction properties and applications of Tb-Dy-Fe alloys: a review

    Directory of Open Access Journals (Sweden)

    Nai-juan Wang

    2016-03-01

    Full Text Available As an excellent giant-magnetostrictive material, Tb-Dy-Fe alloys (based on Tb0.27-0.30Dy0.73-0.70Fe1.9-2 Laves compound can be applied in many engineering fields, such as sonar transducer systems, sensors, and micro-actuators. However, the cost of the rare earth elements Tb and Dy is too high to be widely applied for the materials. Nowadays, there are two different ways to substitute for these alloying elements. One is to partially replace Tb or Dy by cheaper rare earth elements, such as Pr, Nd, Sm and Ho; and the other is to use non-rare earth elements, such as Co, Al, Mn, Si, Ce, B, Be and C, to substitute Fe to form single MgCu2-type Laves phase and a certain amount of Re-rich phase, which can reduce the brittleness and improve the corrosion resistance of the alloy. This paper systemically introduces the development, the fabrication methods and the corresponding preferred growth directions of Tb-Dy-Fe alloys. In addition, the effects of alloying elements and heat treatment on magnetostrictive and mechanical properties of Tb-Dy-Fe alloys are also reviewed, respectively. Finally, some possible applications of Tb-Dy-Fe alloys are presented.

  11. A review of instanton physics

    International Nuclear Information System (INIS)

    Callan, C.G. Jr.

    1979-01-01

    This is a review paper on the developments in the understanding of QCD, that have flowed from the discovery of instanton. The underlying aim is to gain insight by identifying essential degrees of freedom and to simplify the mathematics by throwing away inessential degrees of freedom. By familiar arguments, all the information in a field theory is contained in the Euclidean Functional Integral (EFI). The solution called instanton is of the kind envisaged by Polyakov since it is localized and has finite action. The instanton can be examined from the point of view of vacuum tunneling. One massless fermion flavor makes some remarkable modification. Among the mathematical developments, the most important is the problem of finding the multi-instanton solution. Another useful development has been the calculation in explicit form of the effect of instantons on the propagation of other field. The contribution of single instantons to the vacuum functional is expected. Effects from instanton fluctuation can be determined qualitatively. Typical of these is the calculation of the heavy quark potential by the device of computing the effect of dilute instanton gas on the Wilson loop. Remarks on the interaction between instantons and the effective coupling of instantons of large scale size are described. (Kato, T.)

  12. Electronic structures and relevant physical properties of Ni2MnGa alloy films

    International Nuclear Information System (INIS)

    Kim, K. W.; Kim, J. B.; Huang, M. D.; Lee, N. N.; Lee, Y. P.; Kudryavtsev, Y. V.; Rhee, J. Y.

    2004-01-01

    The electronic structures and physical properties of the ordered and disordered Ni 2 MnGa alloy films were investigated in this study. Ordered and disordered Ni 2 MnGa alloy films were prepared by flash evaporation onto substrates maintained at 720 K and 150 K, respectively. The results show that the ordered films behave in nearly the same way as the bulk Ni 2 MnGa ferromagnetic shape-memory alloy, including the martensitic transformation at 200 K. It was also revealed that the film deposition onto substrates cooled by liquid nitrogen leads to the formation of a substantially-disordered or an amorphous phase which is not ferromagnetically ordered at room temperature. An annealing of such an amorphous film restores its crystallinity and also recovers the ferromagnetic order. It was also clarified how the structural disordering in the films influences the physical properties, including the loss of ferromagnetism in the disordered films, by performing electronic-structure calculations and a photoemission study.

  13. Review of Particle Physics, 2014-2015

    CERN Document Server

    Olive, K A; Amsler, C; Antonelli, M; Arguin, J-F; Asner, D M; Baer, H; Band, H R; Barnett, R M; Basaglia, T; Bauer, C W; Beatty, J J; Belousov, V I; Beringer, J; Bernardi, G; Bethke, S; Bichsel, H; Biebel, O; Blucher, E; Blusk, S; Brooijmans, G; Buchmueller, O; Burkert, V; Bychkov, M A; Cahn, R N; Carena, M; Ceccucci, A; Cerri, A; Chakraborty, D; Chen, M-C; Chivukula, R S; Copic, K; Cowan, G; Dahl, O; D'Ambrosio, G; Damour, T; de Florian, D; de Gouvea, A; DeGrand, T; de Jong, P; Dissertori, G; Dobrescu, B A; Doser, M; Drees, M; Dreiner, H K; Edwards, D A; Eidelman, S; Erler, J; Ezhela, V V; Fetscher, W; Fields, B D; Foster, B; Freitas, A; Gaisser, T K; Gallagher, H; Garren, L; Gerber, H-J; Gerbier, G; Gershon, T; Gherghetta, T; Golwala, S; Goodman, M; Grab, C; Gritsan, A V; Grojen, C; Groom, D E; Grunewald, M; Gurtu, A; Gutsche, T; Haber, H E; Hagiwara, K; Hanhart, C; Hashimoto, S; Hayato, Y; Hayes, K G; Heffner, M; Heltsley, B; Hernandez-Rey, J J; Hikasa, K; Hocker, A; Holder, J; Holtkamp, A; Huston, J; Jackson, J D; Johnson, K F; Junk, T; Kado, M; Karlen, D; Katz, U F; Klein, S R; Klempt, E; Kowalewski, R V; Krauss, F; Kreps, M; Krusche, B; Kuyanov, Yu V; Kwon, Y; Lahav, O; Laiho, J; Langacker, P; Liddle, A; Ligeti, Z; Lin, C-J; Liss, T M; Littenberg, L; Lugovsky, K S; Lugovsky, S B; Maltoni, F; Mannel, T; Manohar, A V; Marciano, W J; Martin, A D; Masoni, A; Matthews, J; Milstead, D; Molaro, P; Munig, K; Moortgat, F; Mortonson, M J; Murayama, H; Nakamura, K; Narain, M; Nason, P; Navas, S; Neubert, M; Nevski, P; Nir, Y; Pape, L; Parsons, J; Patrignani, C; Peacock, J A; Pennington, M; Petcov, S T; Piepke, A; Pomarol, A; Quadt, A; Raby, S; Rademacker, J; Raffelt, G; Ratcliff, B N; Richardson, P; Ringwald, A; Roesler, S; Rolli, S; Romaniouk, A; Rosenberg, L J; Rosner, J L; Rybka, G; Sachrajda, C T; Sakai, Y; Salam, G P; Sarkar, S; Sauli, F; Schneider, O; Scholberg, K; Scott, D; Sharma, V; Sharpe, S R; Silari, M; Sjostrand, T; Skands, P; Smith, J G; Smoot, G F; Spanier, S; Spieler, H; Spiering, C; Stahl, A; Stanev, T; Stone, S L; Sumiyoshi, T; Syphers, M J; Takahashi, F; Tanabashi, M; Terning, J; Tiator, L; Titov, M; Tkachenko, N P; Tornqvist, N A; Tovey, D; Valencia, G; Venanzoni, G; Vincter, M G; Vogel, P; Vogt, A; Wakely, S P; Walkowiak, W; Walter, C W; Ward, D R; Weiglein, G; Weinberg, D H; Weinberg, E J; White, M; Wiencke, L R; Wohl, C G; Wolfenstein, L; Womersley, J; Woody, C L; Workman, R L; Yamamoto, A; Yao, W-M; Zeller, G P; Zenin, O V; Zhang, J; Zhu, R-Y; Zimmermann, F; Zyla, P A; Harper, G; Lugovsky, V.S; Schaffner, P

    2014-01-01

    The Review summarizes much of particle physics and cosmology. Using data from previous editions, plus 3,283 new measurements from 899 papers, we list, evaluate, and average measured properties of gauge bosons and the recently discovered Higgs boson, leptons, quarks, mesons, and baryons. We summarize searches for hypothetical particles such as heavy neutrinos, supersymmetric and technicolor particles, axions, dark photons, etc. All the particle properties and search limits are listed in Summary Tables. We also give numerous tables, figures, formulae, and reviews of topics such as Supersymmetry, Extra Dimensions, Particle Detectors, Probability, and Statistics. Among the 112 reviews are many that are new or heavily revised including those on: Dark Energy, Higgs Boson Physics, Electroweak Model, Neutrino Cross Section Measurements, Monte Carlo Neutrino Generators, Top Quark, Dark Matter, Dynamical Electroweak Symmetry Breaking, Accelerator Physics of Colliders, High-Energy Collider Parameters, Big Bang Nucleosyn...

  14. Synthesis, Structure, Te Alloying, and Physical Properties of CuSbS2.

    Science.gov (United States)

    Hobbis, Dean; Wei, Kaya; Wang, Hsin; Martin, Joshua; Nolas, George S

    2017-11-20

    Materials with very low thermal conductivities continue to be of interest for a variety of applications. We synthesized CuSbS 2 employing a mechanical alloying technique in order to investigate its physical properties. The trigonal pyramid arrangement of the S atoms around the Sb atoms allows for lone-pair electron formation that results in very low thermal conductivity. In addition to thermal properties, the structural, electrical, and optical properties, as well as compositional stability measurements, are also discussed. CuSbS 1.8 Te 0.2 was similarly synthesized and characterized in order to compare its structural and transport properties with that of CuSbS 2 , in addition to investigating the effect of Te alloying on these properties.

  15. A review of recoil ion physics

    International Nuclear Information System (INIS)

    Gray, T.D.; Cocke, C.L.

    1983-01-01

    A review of recoil ion physics is presented. A brief history on the subject is introduced. The production of low velocity highly-charged recoil ions by fast heavy ion beams is discussed. Experiments which utilize the LEHQ beams to measure charge exchange cross sections and energy gain spectroscopy are discussed

  16. Review of PWSCC and mitigation management strategies of Alloy 600 materials of PWRs

    Science.gov (United States)

    Hwang, Seong Sik

    2013-11-01

    Primary water stress corrosion cracking (PWSCC) of Alloy 600 penetration nozzles in pressurized water reactors (PWRs) was reported in the control rod drive mechanism (CRDM), pressurizer instrumentation, and pressurizer heater sleeves. Recently, two cases of boric acid precipitation that indicated leaking of the primary cooling water were reported on the bottom head surface of the steam generators (SGs) in Korea. PWSCC crack indication in CRDM was also detected in a Korea plant. It is necessary to set up a rigid maintenance and inspection guidelines for the components. The PWSCC history of Alloy 600 penetration nozzles of PWRs and maintenance strategies are reviewed based upon the open literature and some experiences in Korea. The inspection requirements, repair techniques such as material changes, the isolation, weld overlays, stress improvements, water chemistry changes are reviewed. Management strategies for the Alloy 600 nozzles are also described.

  17. A Review of TiNiPdCu Alloy System for High Temperature Shape Memory Applications

    Science.gov (United States)

    Khan, M. Imran; Kim, Hee Young; Miyazaki, Shuichi

    2015-06-01

    High temperature shape memory alloys (HTSMAs) are important smart materials and possess a significant potential to improve many engineering systems. Many TiNi-based high temperature ternary alloy systems have been reported in literature including TiNiPd, TiNiPt, TiNiZr, TiNiAu, TiNiHf, etc. Some quaternary additions of certain elements in the above systems have been successful to further improve many important shape memory and mechanical properties. The success criteria for an HTSMA become strict in terms of its cyclic stability, maximum recoverable strain, creep resistance, and corrosion resistance at high temperatures. TiNiPdCu alloy system has been recently proposed as a promising HTSMA. Unique nanoscaled precipitates formed in TiNiPdCu-based HTSMAs are found to be stable at temperatures above 773 K, while keeping the benefits of ease of fabrication. It is expected that this alloy system possesses significant potential especially for the high temperature shape memory applications. Till now many research reports have been published on this alloy system. In the present work, a comprehensive review of the TiNiPdCu system is presented in terms of thermomechanical behavior, nanoscale precipitation mechanism, microstructural features, high temperature shape memory and mechanical properties, and the important parameters to control the high temperature performance of these alloys.

  18. Changes in the physical and mechanical properties of Al-Mg alloy processed by severe plastic deformation

    Science.gov (United States)

    Krasnoveikin, V. A.; Kozulin, A. A.; Skripnyak, V. A.; Moskvichev, E. N.; Borodulin, D. A.

    2017-12-01

    This paper presents the results of studies into the effect of severe plastic deformation on the microstructure, physical and mechanical properties of coarse-grained Al-Mg alloy 1560 in the as-received state with an average grain size of 50 µm. Severe plastic deformation is performed by four-pass equal channel angular pressing (ECAP), which results in the formation of an ultrafine-grained structure with an average grain size of 3 µm in the alloy. Analysis of experimental data revealed that the physical and mechanical properties change significantly after severe plastic deformation. The microhardness of the ECAPed alloy increases by 50%, tensile yield strength by 80%, and ultimate strength by 44% in comparison with these parameters in the as-received state. The constants of approximating functions have been determined for the experimental stress-strain curves of the alloy specimens in the as-received and ECAPed states.

  19. Physical and Mechanical Properties of W-Ni-Fe-Co Metal Foam Modified by Titanium Tungsten Carbide Alloying

    Science.gov (United States)

    Ishchenko, A. N.; Tabachenko, A. N.; Afanas'eva, S. A.; Belov, N. N.; Biryukov, Yu. A.; Burkin, V. V.; D'yachkovskii, A. S.; Rogaev, K. S.; Skosyrskii, A. B.; Yugov, N. T.

    2018-02-01

    The paper studies physical and mechanical properties of tungsten-nickel-iron-cobalt metal foam alloyed with titanium tungsten carbide. Test specimens are obtained by the liquid phase sintering of powder materials, including those containing tungsten nanopowders. High porosity metal foams are prepared through varying the porosity of powder specimens and the content of filling material. The penetration capability of cylinder projectiles made of new alloys is explored in this paper. It is shown that their penetration depth exceeds that of the prototype with relevant weight and size, made of tungsten-nickel-iron alloy, other factors being equal.

  20. Final report on characterization of physical and mechanical properties of copper and copper alloys before and after irradiation

    DEFF Research Database (Denmark)

    Singh, B.N.; Tähtinen, S.

    2002-01-01

    The present report summarizes and highlights the main results of the work carried out during the last 5-6 years on effects of neutron irradiation on physical and mechanical properties of copper and copper alloys. The work was an European contribution toITER Research and Development programme...... the suitability of a copper alloy for its use in the first wall and divertor components of ITER. It is pointed out that the present work has managed onlyto identify some of the critical problems and limitations of the copper alloys for their employment in the hostile environment of 14 MeV neutrons. A considerable...

  1. 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

  2. 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.

  3. Review on the current state of developing of advanced Creep Damage Constitutive Equations for high Chromium Alloy

    OpenAIRE

    An, Lili; Xu, Qiang; Xu, Donglai; Lu, Zhongyu

    2012-01-01

    This paper presents a review of developing of creep damage constitutive equations for high chromium alloy (such as P91 alloy). Firstly, it briefly introduces the background of creep damage for P91 materials. Then, it summarizes the typical creep damage constitutive equations developed and applied for P91 alloy, and the main deficiencies of KRH (Kachanov-Robatnov-Hayhurst) type and Xus type constitutive equations. Finally it suggests the directions for future work. This paper contributes to th...

  4. A Review of Alloy 800H for Applications in the Gen IV Nuclear Energy Systems

    International Nuclear Information System (INIS)

    Ren, Weiju; Swindeman, Robert W.

    2010-01-01

    Alloy 800H is currently under consideration for applications in the Next Generation Nuclear Plant at operational temperatures above 750 C. To provide supporting information in this paper at the attempt to facilitate the consideration, service requirements of the nuclear system for structural materials is first described; and then an extensive review of Alloy 800H is given on its codification with respect to development and research history, mechanical behavior and design allowables, metallurgical aging resistance, environmental effect considerations, data requirements and availability, weldments, as well as many other aspects relevant to the intended nuclear application; an finally further research and development activities to support the materials qualification are suggested.

  5. Effect of alloying elements on austempered ductile iron (ADI properties and its process: Review

    Directory of Open Access Journals (Sweden)

    Amir Sadighzadeh Benam

    2015-01-01

    Full Text Available Austempered ductile iron (ADI parts have a unique combination of high strength and toughness with excellent design flexibility and low cost. These excellent properties are directly related to its microstructure called "ausferrite" that is the result of austempering heat treatment applied to ductile irons. Alloying elements increase ADI austemperability and change speeds of austempering reactions. Thus, they can affect ADI resultant microstructure and mechanical properties. In this paper, the effects of alloying elements on ADI mechanical properties, microstructural changes, two-stage austempering reactions, processing windows, austemperability, and other aspects are reviewed.

  6. Properties and applications of ion-implanted alloys

    International Nuclear Information System (INIS)

    Myers, S.M.

    1979-01-01

    Ion implantation is a controlled and versatile means for near-surface alloying of metals. Supersaturated solutions, metastable compounds, amorphous phases, and equilibrium alloys have been produced. Uses include the investigation of new metastable phases, characterization of alloying reactions occurring in conventional materials, and improvement of surface properties such as hardness, wear, and corrosion. A brief review is given of the physical processes occurring during ion implantation, the types of alloys which result, and representative applications

  7. A review on shape memory alloys with applications to morphing aircraft

    OpenAIRE

    Barbarino, S; Saavedra Flores, E I; Ajaj, R M; Dayyani, I; Friswell, M I

    2014-01-01

    Shape memory alloys (SMAs) are a unique class of metallic materials with the ability to recover their original shape at certain characteristic temperatures (shape memory effect), even under high applied loads and large inelastic deformations, or to undergo large strains without plastic deformation or failure (super-elasticity). In this review, we describe the main features of SMAs, their constitutive models and their properties. We also review the fatigue behavior of SMAs and some methods ado...

  8. Review of electron beam therapy physics

    International Nuclear Information System (INIS)

    Hogstrom, Kenneth R; Almond, Peter R

    2006-01-01

    For over 50 years, electron beams have been an important modality for providing an accurate dose of radiation to superficial cancers and disease and for limiting the dose to underlying normal tissues and structures. This review looks at many of the important contributions of physics and dosimetry to the development and utilization of electron beam therapy, including electron treatment machines, dose specification and calibration, dose measurement, electron transport calculations, treatment and treatment-planning tools, and clinical utilization, including special procedures. Also, future changes in the practice of electron therapy resulting from challenges to its utilization and from potential future technology are discussed. (review)

  9. Review of physics results from the Tevatron: QCD physics

    Energy Technology Data Exchange (ETDEWEB)

    Mesropian, Christina [Rockefeller U.; Bandurin, Dmitry [Virginia U.

    2015-02-17

    We present a summary of results from studies of quantum chromodynamics at the Fermilab Tevatron collider by the CDF and the D0 experiments. These include Run II results for the time period up to the end of Summer 2014. A brief description of Run I results is also given. This review covers a wide spectrum of topics, and includes measurements with jet and vector boson final states in the hard (perturbative) energy regime, as well as studies of soft physics such as diffractive and elastic scatterings, underlying and minimum bias events, hadron fragmentation, and multiple parton interactions.

  10. Interfacial Reaction of Sn-Ag-Cu Lead-Free Solder Alloy on Cu: A Review

    Directory of Open Access Journals (Sweden)

    Liu Mei Lee

    2013-01-01

    Full Text Available This paper reviews the function and importance of Sn-Ag-Cu solder alloys in electronics industry and the interfacial reaction of Sn-Ag-Cu/Cu solder joint at various solder forms and solder reflow conditions. The Sn-Ag-Cu solder alloys are examined in bulk and in thin film. It then examines the effect of soldering conditions to the formation of intermetallic compounds such as Cu substrate selection, structural phases, morphology evolution, the growth kinetics, temperature and time is also discussed. Sn-Ag-Cu lead-free solder alloys are the most promising candidate for the replacement of Sn-Pb solders in modern microelectronic technology. Sn-Ag-Cu solders could possibly be considered and adapted in miniaturization technologies. Therefore, this paper should be of great interest to a large selection of electronics interconnect materials, reliability, processes, and assembly community.

  11. Workplace physical activity interventions: a systematic review

    OpenAIRE

    Dugdill, L; Brettle, A; Hulme, C; McCluskey, S; Long, AF

    2008-01-01

    Purpose – This paper aims to report a synopsis of a recent systematic review of the literature regarding the effectiveness of workplace physical activity interventions, commissioned by the National Institute for Health and Clinical Excellence (NICE). \\ud \\ud Design/methodology/approach – A search for English-language papers published between 1996 and 2007 was conducted using 12 relevant databases and associated grey literature. Search protocols and analysis regarding study quality as recommen...

  12. Essay: Reflections on Physical Review Letters

    Science.gov (United States)

    Lazarus, David

    2008-08-01

    During my tenure as APS Editor-in-Chief Physical Review Letters changed from a journal whose authors were mostly from the U.S. to one whose authors were mostly from abroad. I encouraged authors to publicize their work even before their papers were accepted for publication. And I sought to raise the quality of the papers that were published even higher than before.

  13. Fracture mechanics of pseudoelastic NiTi alloys: review of the research activities carried out at University of Calabria

    Directory of Open Access Journals (Sweden)

    E. Sgambitterra

    2013-01-01

    Full Text Available This paper reports a brief review of the research activities on fracture mechanics of nickel-titanium based shape memory alloys carried out at University of Calabria. In fact, this class of metallic alloys show a unusual fracture response due to the reversible stress-induced and thermally phase transition mechanisms occurring in the crack tip region as a consequence of the highly localized stresses. The paper illustrates the main results concerning numerical, analytical and experimental research activities carried out by using commercial NiTi based pseudoelastic alloys. Furthermore, the effect of several thermo-mechanical loading conditions on the fracture properties of NiTi alloys are illustrated.

  14. Review of Particle Physics, 2012-2013

    CERN Document Server

    Beringer, J; Barnett, R M; Copic, K; Dahl, O; Groom, D E; Lin, C J; Lys, J; Murayama, H; Wohl, C G; Yao, W M; Zyla, P A; Amsler, C; Antonelli, M; Asner, D M; Baer, H; Band, H R; Basaglia, T; Bauer, C W; Beatty, J J; Belousov, V I; Bergren, E; Bernardi, G; Bertl, W; Bethke, S; Bichsel, H; Biebel, O; Blucher, E; Blusk, S; Brooijmans, G; Buchmueller, O; Cahn, R N; Carena, M; Ceccucci, A; Chakraborty, D; Chen, M C; Chivukula, R S; Cowan, G; D'Ambrosio, G; Damour, T; de Florian, D; de Gouvea, A; DeGrand, T; de Jong, P; Dissertori, G; Dobrescu, B; Doser, M; Drees, M; Edwards, D A; Eidelman, S; Erler, J; Ezhela, V V; Fetscher, W; Fields, B D; Foster, B; Gaisser, T K; Garren, L; Gerber, H J; Gerbier, G; Gherghetta, T; Golwala, S; Goodman, M; Grab, C; Gritsan, A V; Grivaz, J F; Grunewald, M; Gurtu, A; Gutsche, T; Haber, H E; Hagiwara, K; Hagmann, C; Hanhart, C; Hashimoto, S; Hayes, K G; Heffner, M; Heltsley, B; Hernandez-Rey, J J; Hikasa, K; Hocker, A; Holder, J; Holtkamp, A; Huston, J; Jackson, J D; Johnson, K F; Junk, T; Karlen, D; Kirkby, D; Klein, S R; Klempt, E; Kowalewski, R V; Krauss, F; Kreps, M; Krusche, B; Kuyanov, Yu.V; Kwon, Y; Lahav, O; Laiho, J; Langacker, P; Liddle, A; Ligeti, Z; Liss, T M; Littenberg, L; Lugovsky, K S; Lugovsky, S B; Mannel, T; Manohar, A V; Marciano, W J; Martin, A D; Masoni, A; Matthews, J; Milstead, D; Miquel, R; Monig, K; Moortgat, F; Nakamura, K; Narain, M; Nason, P; Navas, S; Neubert, M; Nevski, P; Nir, Y; Olive, K A; Pape, L; Parsons, J; Patrignani, C; Peacock, J A; Petcov, S T; Piepke, A; Pomarol, A; Punzi, G; Quadt, A; Raby, S; Raffelt, G; Ratcliff, B N; Richardson, P; Roesler, S; Rolli, S; Romaniouk, A; Rosenberg, L J; Rosner, J L; Sachrajda, C T; Sakai, Y; Salam, G P; Sarkar, S; Sauli, F; Schneider, O; Scholberg, K; Scott, D; Seligman, W G; Shaevitz, M H; Sharpe, S R; Silari, M; Sjostrand, T; Skands, P; Smith, J G; Smoot, G F; Spanier, S; Spieler, H; Stahl, A; Stanev, T; Stone, S L; Sumiyoshi, T; Syphers, M J; Takahashi, F; Tanabashi, M; Terning, J; Titov, M; Tkachenko, N P; Tornqvist, N A; Tovey, D; Valencia, G; van Bibber, K; Venanzoni, G; Vincter, M G; Vogel, P; Vogt, A; Walkowiak, W; Walter, C W; Ward, D R; Watari, T; Weiglein, G; Weinberg, E J; Wiencke, L R; Wolfenstein, L; Womersley, J; Woody, C L; Workman, R L; Yamamoto, A; Zeller, G P; Zenin, O V; Zhang, J; Zhu, R Y; Harper, G; Lugovsky, V S; Schaffner, P

    2012-01-01

    This biennial Review summarizes much of particle physics. Using data from previous editions, plus 2658 new measurements from 644 papers, we list, evaluate, and average measured properties of gauge bosons, leptons, quarks, mesons, and baryons. We summarize searches for hypothetical particles such as Higgs bosons, heavy neutrinos, and supersymmetric particles. All the particle properties and search limits are listed in Summary Tables. We also give numerous tables, figures, formulae, and reviews of topics such as the Standard Model, particle detectors, probability, and statistics. Among the 112 reviews are many that are new or heavily revised including those on Heavy-Quark and Soft-Collinear Effective Theory, Neutrino Cross Section Measurements, Monte Carlo Event Generators, Lattice QCD, Heavy Quarkonium Spectroscopy, Top Quark, Dark Matter, Vcb & Vub, Quantum Chromodynamics, High-Energy Collider Parameters, Astrophysical Constants, Cosmological Parameters, and Dark Matter.

  15. Nuclear physics in particle therapy: a review.

    Science.gov (United States)

    Durante, Marco; Paganetti, Harald

    2016-09-01

    Charged particle therapy has been largely driven and influenced by nuclear physics. The increase in energy deposition density along the ion path in the body allows reducing the dose to normal tissues during radiotherapy compared to photons. Clinical results of particle therapy support the physical rationale for this treatment, but the method remains controversial because of the high cost and of the lack of comparative clinical trials proving the benefit compared to x-rays. Research in applied nuclear physics, including nuclear interactions, dosimetry, image guidance, range verification, novel accelerators and beam delivery technologies, can significantly improve the clinical outcome in particle therapy. Measurements of fragmentation cross-sections, including those for the production of positron-emitting fragments, and attenuation curves are needed for tuning Monte Carlo codes, whose use in clinical environments is rapidly increasing thanks to fast calculation methods. Existing cross sections and codes are indeed not very accurate in the energy and target regions of interest for particle therapy. These measurements are especially urgent for new ions to be used in therapy, such as helium. Furthermore, nuclear physics hardware developments are frequently finding applications in ion therapy due to similar requirements concerning sensors and real-time data processing. In this review we will briefly describe the physics bases, and concentrate on the open issues.

  16. Review of environmental physics activities in Egypt

    International Nuclear Information System (INIS)

    Comsan, M.N.H.

    2005-01-01

    Efforts and activities in Egypt serving the environment went back to 1962. At that time simultaneously were established the Atomic Fallout Laboratory at the premises of Atomic Energy Establishment in Inshas, and the A ir Pollution Unit w ithin the premises of the National Research Centre in Dokki. Recent activities include: radiation monitoring, atmospheric physics, renewable energy pollution control, environmental impact, etc.The article aims at reviewing environmental physics activities in Egypt ; both on governmental and non-governmental scales.The environment is one of the most vital axes of development, so the deterioration of the environment represents a major danger threatening social and economic development, the sustainability of natural resources, and human health.Recognizing this major importance and necessity of the protection of environment and its vital role in our lives, governments all over the globe began to take larger steps towards a better and healthier environment

  17. Review of electron beam therapy physics.

    Science.gov (United States)

    Hogstrom, Kenneth R; Almond, Peter R

    2006-07-07

    For over 50 years, electron beams have been an important modality for providing an accurate dose of radiation to superficial cancers and disease and for limiting the dose to underlying normal tissues and structures. This review looks at many of the important contributions of physics and dosimetry to the development and utilization of electron beam therapy, including electron treatment machines, dose specification and calibration, dose measurement, electron transport calculations, treatment and treatment-planning tools, and clinical utilization, including special procedures. Also, future changes in the practice of electron therapy resulting from challenges to its utilization and from potential future technology are discussed.

  18. A Review Corrosion of TI Grade 7 and Other TI Alloys in Nuclear Waste Repository Environments

    Energy Technology Data Exchange (ETDEWEB)

    F. Hua; K. Mon; P. Pasupathi; G. Gordon

    2004-05-11

    Titanium alloy degradation modes are reviewed in relation to their performance in repository environments. General corrosion, localized corrosion, stress corrosion cracking, hydrogen induced cracking, microbially influenced corrosion, and radiation-assisted corrosion of Ti alloys are considered. With respect to the Ti Grade 7 drip shields selected for emplacement in the repository at Yucca Mountain, general corrosion, hydrogen induced cracking, and radiation-assisted corrosion will not lead to failure within the 10,000 year regulatory period; stress corrosion cracking (in the absence of disruptive events) is of no consequence to barrier performance; and localized corrosion and microbially influenced corrosion are not expected to occur. To facilitate the discussion, Ti Grades 2, 5, 7, 9, 11, 12, 16, 17, 18, and 24 are included in this review.

  19. Physical activity in spondyloarthritis: a systematic review.

    Science.gov (United States)

    O'Dwyer, Tom; O'Shea, Finbar; Wilson, Fiona

    2015-03-01

    Physical activity (PA) is associated with numerous health-related benefits among adults with chronic diseases and the general population. As the benefits are dose-dependent, this review aims to establish the PA levels of adults with spondyloarthritis and to compare these to the general population. Electronic databases (Cochrane Central Register of Controlled Trials, EMBASE, MEDLINE/PubMed, PEDro, AMED, CINAHL) were systematically searched from inception to May 2014 using medical subject headings and keywords. This was supplemented by searching conference abstracts and hand-searching reference lists of included studies. Eligible studies were randomized controlled trials and observational studies of adults with SpA in which free-living PA or energy expenditure levels were measured. Subjects less than 18 years or with juvenile-onset SpA were excluded. Outcomes included objective and self-report measurements. Two reviewers independently screened studies for inclusion and assessed methodological quality using the Cochrane risk of bias tool and the RTI item bank. From the 2,431 records reviewed, nine studies involving 2,972 participants were included. This review focused on qualitative synthesis. Meta-analyses were not undertaken due to differences in study design, measurement tools, and participant characteristics. This heterogeneity, coupled with the risk of bias inherent in the included observational studies, limits the generalizability of findings. Objective measurements suggest PA levels may be lower among adults with spondyloarthritis than in healthy population controls. Self-reported PA and self-reported rates of adherence to PA recommendations varied largely across studies; higher disease activity was associated with lower self-reported PA levels. Physical activity levels may be lower in adults with axial spondyloarthritis, with higher disease activity associated with lower PA levels.

  20. Physical activity in spondyloarthritis: a systematic review

    LENUS (Irish Health Repository)

    O’Dwyer, Tom

    2014-10-01

    Physical activity (PA) is associated with numerous health-related benefits among adults with chronic diseases and the general population. As the benefits are dose-dependent, this review aims to establish the PA levels of adults with spondyloarthritis and to compare these to the general population. Electronic databases (Cochrane Central Register of Controlled Trials, EMBASE, MEDLINE\\/PubMed, PEDro, AMED, CINAHL) were systematically searched from inception to May 2014 using medical subject headings and keywords. This was supplemented by searching conference abstracts and hand-searching reference lists of included studies. Eligible studies were randomized controlled trials and observational studies of adults with SpA in which free-living PA or energy expenditure levels were measured. Subjects less than 18 years or with juvenile-onset SpA were excluded. Outcomes included objective and self-report measurements. Two reviewers independently screened studies for inclusion and assessed methodological quality using the Cochrane risk of bias tool and the RTI item bank. From the 2,431 records reviewed, nine studies involving 2,972 participants were included. This review focused on qualitative synthesis. Meta-analyses were not undertaken due to differences in study design, measurement tools, and participant characteristics. This heterogeneity, coupled with the risk of bias inherent in the included observational studies, limits the generalizability of findings. Objective measurements suggest PA levels may be lower among adults with spondyloarthritis than in healthy population controls. Self-reported PA and self-reported rates of adherence to PA recommendations varied largely across studies; higher disease activity was associated with lower self-reported PA levels. Physical activity levels may be lower in adults with axial spondyloarthritis, with higher disease activity associated with lower PA levels.

  1. Review of Creep Cavitation and Rupture of Low Cr Alloy and its Weldment

    OpenAIRE

    Xu, Qihua; Xu, Qiang; Pang, Yongxin; Short, Michael

    2013-01-01

    This paper presents a review of creep cavitation and rupture of low Cr alloy and its weldment, particular in the heat-affected zone (HAZ). Creep damage is one of the serious problems for the high temperature industry. One of the computational approaches is continuum damage mechanics which has been developed and applied complementary to the experimental approach and assists in the safe operation. However, the existing creep damage constitutive equations are not developed specifically for low s...

  2. Physico-mechanical properties and prosthodontic applications of Co-Cr dental alloys: a review of the literature

    Science.gov (United States)

    2014-01-01

    Cobalt-Chromium (Co-Cr) alloys are classified as predominantly base-metal alloys and are widely known for their biomedical applications in the orthopedic and dental fields. In dentistry, Co-Cr alloys are commonly used for the fabrication of metallic frameworks of removable partial dentures and recently have been used as metallic substructures for the fabrication of porcelain-fused-to-metal restorations and implant frameworks. The increased worldwide interest in utilizing Co-Cr alloys for dental applications is related to their low cost and adequate physico-mechanical properties. Additionally, among base-metal alloys, Co-Cr alloys are used more frequently in many countries to replace Nickel-Chromium (Ni-Cr) alloys. This is mainly due to the increased concern regarding the toxic effects of Ni on the human body when alloys containing Ni are exposed to the oral cavity. This review article describes dental applications, metallurgical characterization, and physico-mechanical properties of Co-Cr alloys and also addresses their clinical and laboratory behavior in relation to those properties. PMID:24843400

  3. Low temperature physical properties of Co-35Ni-20Cr-10Mo alloy MP35N®

    Science.gov (United States)

    Lu, J.; Toplosky, V. J.; Goddard, R. E.; Han, K.

    2017-09-01

    Multiphase Co-35Ni-20Cr-10Mo alloy MP35N® is a high strength alloy with excellent corrosion resistance. Its applications span chemical, medical, and food processing industries. Thanks to its high modulus and high strength, it found applications in reinforcement of ultra-high field pulsed magnets. Recently, it has also been considered for reinforcement in superconducting wires used in ultra-high field superconducting magnets. For these applications, accurate measurement of its physical properties at cryogenic temperatures is very important. In this paper, physical properties including electrical resistivity, specific heat, thermal conductivity, and magnetization of as-received and aged samples are measured from 2 to 300 K. The electrical resistivity of the aged sample is slightly higher than the as-received sample, both showing a weak linear temperature dependence in the entire range of 2-300 K. The measured specific heat Cp of 430 J/kg-K at 295 K agrees with a theoretical prediction, but is significantly smaller than the values in the literature. The thermal conductivity between 2 and 300 K is in good agreement with the literature which is only available above 77 K. Magnetic property of MP35N® changes significantly with aging. The as-received sample exhibits Curie paramagnetism with a Curie constant C = 0.175 K. While the aged sample contains small amounts of a ferromagnetic phase even at room temperature. The measured MP35N® properties will be useful for the engineering design of pulsed magnets and superconducting magnets using MP35N® as reinforcement.

  4. A Review of Titanium Zirconium (TiZr Alloys for Use in Endosseous Dental Implants

    Directory of Open Access Journals (Sweden)

    Michel Dard

    2012-08-01

    Full Text Available Dental implants made from binary titanium-zirconium (TiZr alloys have shown promise as a high strength, yet biocompatible alternative to pure titanium, particularly for applications requiring small diameter implants. The aim of this review is to summarize existing literature reporting on the use of binary TiZr alloys for endosseous dental implant applications as tested in vitro, in animals and clinically. And furthermore to show that TiZr is “at least as good as” pure titanium in terms of biocompatibility and osseointergration. From the twelve papers that met the inclusion criteria, the current literature confirms that TiZr alloys produce small diameter implants with a strength up to 40% higher than conventional, cold-worked, grade IV titanium implants, and with a corrosion resistance and biocompatibility that is at least as good as pure titanium. The surface structure of TiZr is compatible with established surface treatments proven to aid in the osseointegration of titanium implants. Furthermore, binary TiZr alloys have been shown to achieve good osseointegration and high success rates both in animal and in clinical studies.

  5. Phosphorus effect on structure and physical properties of iron-nickel alloys

    International Nuclear Information System (INIS)

    Berseneva, F.N.; Kalinin, V.M.; Rybalko, O.F.

    1982-01-01

    The structure and properties of iron-nickel alloys (30-50 % Ni) containing from 0.02 to 0.5 wt. % P have been investigated. It has been found that phosphorus solubility in iron-nickel alloys at most purified from impurities exceeds limiting solubility values usually observed for commercial alloys. Phosphide eutectics precipitation over the grain boundaries of studied alloys occurs but with phosphorus content equal 0.45 wt. %. The 0.4 wt. % P addition in invar alloys increases saturation magnetization and the Curie point and leads to a more homogeneous structure

  6. Evaluating the Tensile Properties of Aluminum Foundry Alloys through Reference Castings—A Review

    Directory of Open Access Journals (Sweden)

    A.R. Anilchandra

    2017-08-01

    Full Text Available The tensile properties of an alloy can be exploited if detrimental defects and imperfections of the casting are minimized and the microstructural characteristics are optimized through several strategies that involve die design, process management and metal treatments. This paper presents an analysis and comparison of the salient characteristics of the reference dies proposed in the literature, both in the field of pressure and gravity die-casting. The specimens produced with these reference dies, called separately poured specimens, are effective tools for the evaluation and comparison of the tensile and physical behaviors of Al-Si casting alloys. Some of the findings of the present paper have been recently developed in the frame of the European StaCast project whose results are complemented here with some more recent outcomes and a comprehensive analysis and discussion.

  7. Evaluating the Tensile Properties of Aluminum Foundry Alloys through Reference Castings-A Review.

    Science.gov (United States)

    Anilchandra, A R; Arnberg, Lars; Bonollo, Franco; Fiorese, Elena; Timelli, Giulio

    2017-08-30

    The tensile properties of an alloy can be exploited if detrimental defects and imperfections of the casting are minimized and the microstructural characteristics are optimized through several strategies that involve die design, process management and metal treatments. This paper presents an analysis and comparison of the salient characteristics of the reference dies proposed in the literature, both in the field of pressure and gravity die-casting. The specimens produced with these reference dies, called separately poured specimens, are effective tools for the evaluation and comparison of the tensile and physical behaviors of Al-Si casting alloys. Some of the findings of the present paper have been recently developed in the frame of the European StaCast project whose results are complemented here with some more recent outcomes and a comprehensive analysis and discussion.

  8. Use of low fusing alloy in dentistry.

    Science.gov (United States)

    Wee, A G; Schneider, R L; Aquilino, S A

    1998-11-01

    Low fusing alloy has been used in dentistry for remount procedures in both fixed and removable prosthodontics, in implant prosthodontics for the fabrication of solid implant casts, in maxillofacial prosthetics as oral radiation shields, and in dental research for its unique properties. Previously, the use of low fusing alloy was thought to offer a high degree of dimensional accuracy. However, multiple in vitro studies have shown that its presumed dimensional accuracy may be questionable. This article reviews the physical properties, metallurgical considerations of low fusing alloy, its applications in dentistry, and a safe, simple method of using low fusing alloy.

  9. Review on ultrafined/nanostructured magnesium alloys produced through severe plastic deformation: microstructures

    Directory of Open Access Journals (Sweden)

    Mahmood Fatemi

    2015-12-01

    Full Text Available A review on the microstructural evolution in magnesium alloys during severe plastic deformation waspresented. The challenges deserved to achieve ultrafine/ nanostructured magnesium were discussed.The characteristics of the processed materials are influenced by three main factors, including idifficult processing at low temperatures, ii high temperature processing and the occurrence ofdynamic recrystallization and grain growth processes, and iii a combined effect of grain refinementand crystallographic texture changes. Reviewing the published results indicate that there are twopotential difficulties with severe deformation of magnesium alloys. First, it is very hard to achievehomogeneous ultrafined microstructure with initial coarse grains. The second is the dependency ofmicrostructure development on the initial grain size and on the imposed strain level. It was clarifiedthat different grain refining mechanisms may be contributed along the course of multi-pass severedeformation. It was clarified that discontinuous recrystallization takes places during the first stages ofdeformation, whereas continuous refinement of the recrystallized grain may be realized at consecutivepasses. Shear band formation as well as twinning were demonstrated to play a significant role in grainrefinement of magnesium alloy. Also, the higher the processing temperature employed the morehomogeneous microstructure may be achieved with higher share of low angle grain boundaries.

  10. Influence of structural transition on the electronic structures and physical properties of Ni2MnGa alloy films

    International Nuclear Information System (INIS)

    Kim, K. W.; Kudryavtsev, Y. V.; Rhee, J. Y.; Lee, N. N.; Lee, Y. P.

    2004-01-01

    Ordered and disordered Ni 2 MnGa alloy films were prepared by flash evaporation onto substrates maintained at 720 K and 150 K, respectively. The results show that the ordered films behave in nearly the same way as the bulk Ni 2 MnGa ferromagnetic shape-memory alloy, including the martensitic transformation at 200 K, while the disordered films exhibit characteristics of amorphous alloys. It was also found that the disordering in Ni 2 MnGa alloy films did not change to any appreciable magnetic ordering down to 4 K. Annealing of the disordered films restores the ordered structure with an almost full recovery of the magnetic, magneto-optical and transport properties of the ordered Ni 2 MnGa alloy films. It was also understood, for the first time, how the structural ordering in the films influences the physical properties, including the surprising loss of ferromagnetism in the disordered films, as a result of performing electronic-structure calculations.

  11. Mg and Mg alloys: how comparable are in vitro and in vivo corrosion rates? A review.

    Science.gov (United States)

    Martinez Sanchez, Adela Helvia; Luthringer, Bérengère J C; Feyerabend, Frank; Willumeit, Regine

    2015-02-01

    Due to their biodegradability, magnesium and magnesium-based alloys could represent the third generation of biomaterials. However, their mechanical properties and time of degradation have to match the needs of applications. Several approaches, such as choice of alloying elements or tailored microstructure, are employed to tailor corrosion behaviour. Due to the high electrochemical activity of Mg, numerous environmental factors (e.g. temperature and surrounding ion composition) influence its corrosion behaviour, making it unpredictable. Nevertheless, the need of reliable in vitro model(s) to predict in vivo implant degradation is increasing. In an attempt to find a correlation between in vitro and vivo corrosion rates, this review presents a systematic literature survey, as well as an attempt to correlate the different results. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  12. Effects of iron irradiation om microstructure and properties of zirconium alloys: A review

    International Nuclear Information System (INIS)

    Yan, Chun Guang; Wang, Yanli; Wang, Xitao; Wang, Rong Shan; Bai, Guang Hai

    2015-01-01

    Zirconium alloys are widely used in nuclear reactors as structural materials. During the operation, they are exposed to fast neutrons. Ion irradiation is used to simulate the damage introduced by neutron irradiation. In this article, we briefly review the neutron irradiation damage of zirconium alloys, then summarize the effect of ion irradiation on microstructural evolution, mechanical and corrosion properties, and their relationships. The microstructure components consist of dislocation loops, second phase precipitates, and gas bubbles. The microstructure parameters are also included such as domain size and microstrain determined by X-ray diffraction and the S-parameter determined by positron annihilation. Understanding the relationships of microstructure and properties is necessary for developing new advanced materials with higher irradiation tolerance.

  13. Review of the Methods for Production of Spherical Ti and Ti Alloy Powder

    Science.gov (United States)

    Sun, Pei; Fang, Zhigang Zak; Zhang, Ying; Xia, Yang

    2017-10-01

    Spherical titanium alloy powder is an important raw material for near-net-shape fabrication via a powder metallurgy (PM) manufacturing route, as well as feedstock for powder injection molding, and additive manufacturing (AM). Nevertheless, the cost of Ti powder including spherical Ti alloy has been a major hurdle that prevented PM Ti from being adopted for a wide range of applications. Especially with the increasing importance of powder-bed based AM technologies, the demand for spherical Ti powder has brought renewed attention on properties and cost, as well as on powder-producing processes. The performance of Ti components manufactured from powder has a strong dependence on the quality of powder, and it is therefore crucial to understand the properties and production methods of powder. This article aims to provide a cursory review of the basic techniques of commercial and emerging methods for making spherical Ti powder. The advantages as well as limitations of different methods are discussed.

  14. Physical nature of strain rate sensitivity of metals and alloys at high strain rates

    Science.gov (United States)

    Borodin, E. N.; Gruzdkov, A. A.; Mayer, A. E.; Selyutina, N. S.

    2018-04-01

    The role of instabilities of plastic flow at plastic deformation of various materials is one of the important cross-disciplinary problems which is equally important in physics, mechanics and material science. The strain rate sensitivities under slow and high strain rate conditions of loading have different physical nature. In the case of low strain rate, the sensitivity arising from the inertness of the defect structures evolution can be expressed by a single parameter characterizing the plasticity mechanism. In our approach, this is the value of the characteristic relaxation time. In the dynamic case, there are additional effects of “high-speed sensitivity” associated with the micro-localization of the plastic flow near the stress concentrators. In the frames of mechanical description, this requires to introduce additional strain rate sensitivity parameters, which is realized in numerous modifications of Johnson–Cook and Zerilli–Armstrong models. The consideration of both these factors is fundamental for an adequate description of the problems of dynamic deformation of highly inhomogeneous metallic materials such as steels and alloys. The measurement of the dispersion of particle velocities on the free surface of a shock-loaded material can be regarded as an experimental expression of the effect of micro-localization. This is also confirmed by our results of numerical simulation of the propagation of shock waves in a two-dimensional formulation and analytical estimations.

  15. BOOK REVIEW: Controlled Fusion and Plasma Physics

    Science.gov (United States)

    Engelmann, F.

    2007-07-01

    This new book by Kenro Miyamoto provides an up-to-date overview of the status of fusion research and the important parts of the underlying plasma physics at a moment where, due to the start of ITER construction, an important step in fusion research has been made and many new research workers will enter the field. For them, and also for interested graduate students and physicists in other fields, the book provides a good introduction into fusion physics as, on the whole, the presentation of the material is quite appropriate for getting acquainted with the field on the basis of just general knowledge in physics. There is overlap with Miyamoto's earlier book Plasma Physics for Nuclear Fusion (MIT Press, Cambridge, USA, 1989) but only in a few sections on subjects which have not evolved since. The presentation is subdivided into two parts of about equal length. The first part, following a concise survey of the physics basis of thermonuclear fusion and of plasmas in general, covers the various magnetic configurations studied for plasma confinement (tokamak; reversed field pinch; stellarator; mirror-type geometries) and introduces the specific properties of plasmas in these devices. Plasma confinement in tokamaks is treated in particular detail, in compliance with the importance of this field in fusion research. This includes a review of the ITER concept and of the rationale for the choice of ITER's parameters. In the second part, selected topics in fusion plasma physics (macroscopic instabilities; propagation of waves; kinetic effects such as energy transfer between waves and particles including microscopic instabilities as well as plasma heating and current drive; transport phenomena induced by turbulence) are presented systematically. While the emphasis is on displaying the essential physics, deeper theoretical analysis is also provided here. Every chapter is complemented by a few related problems, but only partial hints for their solution are given. A selection of

  16. Allergic reactions associated with metal alloys in porcelain-fused-to-metal fixed prosthodontic devices-A systematic review.

    Science.gov (United States)

    Levi, Lauren; Barak, Shlomo; Katz, Joseph

    2012-01-01

    To systematically review the allergic reactions associated with metal alloys in porcelain-fused-to-metal (PFM) fixed prosthetic devices. After reviewing the titles and abstracts of the articles as well as removing duplicates, 22 articles were considered relevant. PubMed, Web of Science, ScienceDirect, and Google Scholar from 1970 to 2012 were evaluated, and randomized studies, review articles, case reports, cross-sectional surveys, and abstracts were included. Conference papers and posters were excluded. Although reported, allergic reactions to metallic alloys in the context of PFM devices are not well documented. Allergic reactions to high noble and noble metal alloy cores of palladium and gold and to base metal alloys nickel and cobalt in the context of PFM fixed partial dentures (FPDs) are reported. Each type of metal is associated with a different rate of allergic reactions, which may be attributed to the extent of corrosion of the alloy, population exposure, and the biologic environment. Because few studies document allergic reactions to metals that comprise PFM crowns and partial dentures, further research in this field is necessary to determine the frequency and type of reactions elicited. Though allergic reactions to metal alloys used in dentistry are well documented, only few articles focus on the correlation between FPDs and metal allergies. Thus, this paper surveys case reports of hypersensitivity reactions linked to FPDs and reviews the current literature on allergic reactions to the metallic elements comprising those devices.

  17. Physical exercise during pregnancy: a systematic review.

    Science.gov (United States)

    Nascimento, Simony L; Surita, Fernanda G; Cecatti, José G

    2012-12-01

    This review aims to provide an update on the recent evidence concerning exercise during pregnancy including effects for mother and fetus and the types, frequency, intensity, duration and rate of progression of exercise performed. Exercises during pregnancy are associated with higher cardiorespiratory fitness, prevention of urinary incontinence and low back pain, reduced symptoms of depression, gestational weight gain control, and for cases of gestational diabetes, reduced number of women who required insulin. There is no association with reduction in birth weight or preterm birth rate. The type of exercise shows no difference on results, and its intensity should be mild or moderate for previous sedentary women and moderate to high for active women. The exercise recommendations still are based on the current guidelines on moderate-intensity, low-impact, aerobic exercise at least three times a week. Yet, new guidelines propose increasing weekly physical-activity expenditure while incorporating vigorous exercise and adding light strength training to the exercise routine of healthy pregnant women. In the case of other chronic diseases like hypertension, there are still few data, and therefore more studies should be performed to assess the safety of the intervention. Physical exercise is beneficial for women during pregnancy and also in the postpartum period; it is not associated with risks for the newborn and can lead to changes in lifestyle that imply long-term benefits.

  18. Statistical physics of crime: a review.

    Science.gov (United States)

    D'Orsogna, Maria R; Perc, Matjaž

    2015-03-01

    Containing the spread of crime in urban societies remains a major challenge. Empirical evidence suggests that, if left unchecked, crimes may be recurrent and proliferate. On the other hand, eradicating a culture of crime may be difficult, especially under extreme social circumstances that impair the creation of a shared sense of social responsibility. Although our understanding of the mechanisms that drive the emergence and diffusion of crime is still incomplete, recent research highlights applied mathematics and methods of statistical physics as valuable theoretical resources that may help us better understand criminal activity. We review different approaches aimed at modeling and improving our understanding of crime, focusing on the nucleation of crime hotspots using partial differential equations, self-exciting point process and agent-based modeling, adversarial evolutionary games, and the network science behind the formation of gangs and large-scale organized crime. We emphasize that statistical physics of crime can relevantly inform the design of successful crime prevention strategies, as well as improve the accuracy of expectations about how different policing interventions should impact malicious human activity that deviates from social norms. We also outline possible directions for future research, related to the effects of social and coevolving networks and to the hierarchical growth of criminal structures due to self-organization. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Observing Tin-Lead Alloys by Scanning Electron Microscopy: A Physical Chemistry Experiment Investigating Macro-Level Behaviors and Micro-Level Structures

    Science.gov (United States)

    Wang, Yue; Xu, Xinhua; Wu, Meifen; Hu, Huikang; Wang, Xiaogang

    2015-01-01

    Scanning electron microscopy (SEM) was introduced into undergraduate physical chemistry laboratory curriculum to help students observe the phase composition and morphology characteristics of tin-lead alloys and thus further their understanding of binary alloy phase diagrams. The students were captivated by this visual analysis method, which…

  20. Physical Modeling of Plastic Working Conditions for Rods of 7xxx Series Aluminum Alloys

    Directory of Open Access Journals (Sweden)

    Dyja H.

    2017-06-01

    Full Text Available The continuing high level of demand for lightweight structural materials is the reason for the ever-growing interest in aluminum alloys. The main areas of application for aluminum alloys products are the aerospace and automotive industries. Production of profiles and structural elements from lightweight alloys gives possibility to reduce the curb weight of construction, which directly translates into among other reduction of fuel consumption and lower amount of generated exhaust gas.

  1. A review on shape memory alloys with applications to morphing aircraft

    International Nuclear Information System (INIS)

    Barbarino, S; Saavedra Flores, E I; Ajaj, R M; Dayyani, I; Friswell, M I

    2014-01-01

    Shape memory alloys (SMAs) are a unique class of metallic materials with the ability to recover their original shape at certain characteristic temperatures (shape memory effect), even under high applied loads and large inelastic deformations, or to undergo large strains without plastic deformation or failure (super-elasticity). In this review, we describe the main features of SMAs, their constitutive models and their properties. We also review the fatigue behavior of SMAs and some methods adopted to remove or reduce its undesirable effects. SMAs have been used in a wide variety of applications in different fields. In this review, we focus on the use of shape memory alloys in the context of morphing aircraft, with particular emphasis on variable twist and camber, and also on actuation bandwidth and reduction of power consumption. These applications prove particularly challenging because novel configurations are adopted to maximize integration and effectiveness of SMAs, which play the role of an actuator (using the shape memory effect), often combined with structural, load-carrying capabilities. Iterative and multi-disciplinary modeling is therefore necessary due to the fluid–structure interaction combined with the nonlinear behavior of SMAs. (topical review)

  2. BOOK REVIEW: Solid State Physics: An Introduction

    Science.gov (United States)

    Jakoby, Bernhard

    2009-07-01

    There's a wealth of excellent textbooks on solid state physics. The author of the present book is well aware of this fact and does not attempt to write just another one. Rather, he has provided a very compact introduction to solid state physics for third-year students. As we are faced with the continuous appearance interdisciplinary fields and associated study curricula in natural and engineering sciences (biophysics, mechatronics, etc), a compact text in solid state physics would be appreciated by students of these disciplines as well. The book features 11 chapters where each is provided with supplementary discussion questions and problems. The first chapters deal with a review of chemical bonding mechanisms, crystal structures and mechanical properties of solids, which are brief but by no means superficial. The following, somewhat more detailed chapter on thermal properties of lattices includes a nice introduction to phonons. The foundations of solid state electronics are treated in the next three chapters. Here the author first discusses the classical treatment of electronic behaviour in metals (Drude model) and continues with a quantum-theoretical approach starting with the free-electron model and leading to the band structures in conductive solids. The next chapter is devoted to semiconductors and ends with a brief but, with respect to the topical scope, adequate discussion of semiconductor devices. The classical topics of magnetic and dielectric behaviour are treated in the sequel. The book closes with a chapter on superconductivity and a brief chapter covering the modern topics of quantum confinement and aspects of nanoscale physics. In my opinion, the author has succeeded in creating a very concise yet not superficial textbook. The account presented often probes subjects deep enough to lay the basis for a thorough understanding, preparing the reader for more specialized textbooks. For instance, I think that this book may serve as an excellent first

  3. Dissolution of metallic uranium and its alloys. Part 1. Review of analytical and process-scale metallic uranium dissolution

    International Nuclear Information System (INIS)

    Laue, C.A.; Gates-Anderson, D.; Fitch, T.E.

    2004-01-01

    This review focuses on dissolution/reaction systems capable of treating uranium metal waste to remove its pyrophoric properties. The primary emphasis is the review of literature describing analytical and production-scale dissolution methods applied to either uranium metal or uranium alloys. A brief summary of uranium's corrosion behavior is included since the corrosion resistance of metals and alloys affects their dissolution behavior. Based on this review, dissolution systems were recommended for subsequent screening studies designed to identify the best system to treat depleted uranium metal wastes at Lawrence Livermore National Laboratory (LLNL). (author)

  4. Tackling Mg alloy corrosion by natural polymer coatings-A review.

    Science.gov (United States)

    Heise, Svenja; Virtanen, Sannakaisa; Boccaccini, Aldo R

    2016-10-01

    The field of protective coatings for magnesium and its alloys (e.g., AZ31) using natural polymers is reviewed. Polymers utilized are broadly divided into polysaccharides and proteins. For both polymer classes examples are given focusing on coating processing and characterization. Several analysing methods reported in literature are summarized highlighting the different characterization approaches applied in different studies, which makes difficult a direct comparison of the outcomes. In most cases, the protective behavior of coatings was determined using electrochemical impedance spectroscopy or by assessing hydrogen evolution in different fluids. Mechanical tests and in vitro cell culture studies have been also carried out on selected coating systems. Overall, the results show the possibility of applying protective coatings based on natural polymers on magnesium and its alloys, however, in vivo investigations are scarce so that long-term results in relevant conditions are not yet available. A comparison with the use of synthetic polymers is presented and current challenges and areas for future research are discussed, highlighting the need for further investigations in the field, which should enable broadening the applications of Mg and Mg alloys in medicine. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2628-2641, 2016. © 2016 Wiley Periodicals, Inc.

  5. Literature review report on atomistic modeling tools for FeCrAl alloys

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yongfeng [Idaho National Lab. (INL), Idaho Falls, ID (United States); Schwen, Daniel [Idaho National Lab. (INL), Idaho Falls, ID (United States); Martinez, Enrique [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-12-01

    This reports summarizes the literature review results on atomistic tools, particularly interatomic potentials used in molecular dynamics simulations, for FeCrAl ternary alloys. FeCrAl has recently been identified as a possible cladding concept for accident tolerant fuels for its superior corrosion resistance. Along with several other concepts, an initial evaluation and recommendation are desired for FeCrAl before it’s used in realistic fuels. For this purpose, sufficient understanding on the in-reactor behavior of FeCrAl needs to be grained in a relatively short timeframe, and multiscale modeling and simulations have been selected as an efficient measure to supplement experiments and in-reactor testing for better understanding on FeCrAl. For the limited knowledge on FeCrAl alloys, the multiscale modeling approach relies on atomistic simulations to obtain the missing material parameters and properties. As a first step, atomistic tools have to be identified and this is the purpose of the present report. It was noticed during the literature survey that no interatomic potentials currently available for FeCrAl. Here, we summarize the interatomic potentials available for FeCr alloys for possible molecular dynamics studies using FeCr as surrogate materials. Other atomistic methods such as lattice kinetic Monte Carlo are also included in this report. A couple of research topics at the atomic scale are suggested based on the literature survey.

  6. Review of the expected behaviour of alpha titanium alloys under Yucca Mountain conditions

    Energy Technology Data Exchange (ETDEWEB)

    Shoesmith, D.W

    2000-03-01

    The use of titanium alloys in two different waste package designs has been reviewed under the, conditions anticipated in the Yucca Mountain nuclear waste repository. In the first design. they are considered as one of three barrier materials incorporated into the waste package design and potentially in galvanic contact with the other two waste package materials, 316L stainless steel and Alloy-22. In the second design the Ti alloy is considered as a drip shield placed over, and not in contact with, a dual wall waste package fabricated from the other two materials. The possible failure processes, crevice corrosion, pitting and hydrogen-induced cracking (HIC) have been reviewed for the candidate titanium alloys (Ti-12, Ti-16 and Ti-7). Both pitting and crevice corrosion are very remote possibilities under these conditions. For Ti-12, a limited amount of crevice corrosion is possible but repassivation will occur before substantial damage is sustained. When Ti is considered as part of the triple wall waste package, hydrogen absorption leading to HIC, within an acidified but passive crevice, is the most likely failure mechanism. When the Ti alloy is utilized in the form of a drip shield then hydrogen absorption under potentially alkaline conditions is the major fear. Both Ti-12 and Ti-16 have been shown capable of tolerating substantial amounts of hydrogen ({approx}400 {mu} g{center_dot}g{sup -1} for Ti-12, and > 1000 {mu}g.g{sup -1} for Ti-16) before any effect on the materials fracture toughness is observed. The rate of absorption to a hydrogen content which exceeds these values will be the key feature determining if, or when, the material becomes susceptible to cracking. Once this condition is achieved, whether or not failure occurs will depend on the strength and location of stresses within the structure. For Ti to absorb hydrogen it is inevitably necessary to subject the material to cathodic polarization, either by coupling to a more active material or by the

  7. Review of the expected behaviour of alpha titanium alloys under Yucca Mountain conditions

    International Nuclear Information System (INIS)

    Shoesmith, D.W.

    2000-03-01

    The use of titanium alloys in two different waste package designs has been reviewed under the, conditions anticipated in the Yucca Mountain nuclear waste repository. In the first design. they are considered as one of three barrier materials incorporated into the waste package design and potentially in galvanic contact with the other two waste package materials, 316L stainless steel and Alloy-22. In the second design the Ti alloy is considered as a drip shield placed over, and not in contact with, a dual wall waste package fabricated from the other two materials. The possible failure processes, crevice corrosion, pitting and hydrogen-induced cracking (HIC) have been reviewed for the candidate titanium alloys (Ti-12, Ti-16 and Ti-7). Both pitting and crevice corrosion are very remote possibilities under these conditions. For Ti-12, a limited amount of crevice corrosion is possible but repassivation will occur before substantial damage is sustained. When Ti is considered as part of the triple wall waste package, hydrogen absorption leading to HIC, within an acidified but passive crevice, is the most likely failure mechanism. When the Ti alloy is utilized in the form of a drip shield then hydrogen absorption under potentially alkaline conditions is the major fear. Both Ti-12 and Ti-16 have been shown capable of tolerating substantial amounts of hydrogen (∼400 μ g·g -1 for Ti-12, and > 1000 μg.g -1 for Ti-16) before any effect on the materials fracture toughness is observed. The rate of absorption to a hydrogen content which exceeds these values will be the key feature determining if, or when, the material becomes susceptible to cracking. Once this condition is achieved, whether or not failure occurs will depend on the strength and location of stresses within the structure. For Ti to absorb hydrogen it is inevitably necessary to subject the material to cathodic polarization, either by coupling to a more active material or by the application of galvanic protection

  8. A Unified Physical Model for Creep and Hot Working of Al-Mg Solid Solution Alloys

    Directory of Open Access Journals (Sweden)

    Stefano Spigarelli

    2017-12-01

    Full Text Available The description of the dependence of steady-state creep rate on applied stress and temperature is almost invariably based on the Norton equation or on derived power-law relationships. In hot working, the Norton equation does not work, and is therefore usually replaced with the Garofalo (sinh equation. Both of these equations are phenomenological in nature and can be seldom unambiguously related to microstructural parameters, such as dislocation density, although early efforts in this sense led to the introduction of the “natural power law” with exponent 3. In an attempt to overcome this deficiency, a recent model with sound physical basis has been successfully used to describe the creep response of fcc metals, such as copper. The main advantage of this model is that it does not require any data fitting to predict the strain rate dependence on applied stress and temperature, which is a particularly attractive peculiarity when studying the hot workability of metals. Thus, the model, properly modified to take into account solid solution strengthening effects, has been here applied to the study of the creep and hot-working of simple Al-Mg single phase alloys. The model demonstrated an excellent accuracy in describing both creep and hot working regimes, still maintaining its most important feature, that is, it does not require any fitting of the experimental data.

  9. A review on shape memory alloys with applications to morphing aircraft

    Science.gov (United States)

    Barbarino, S.; Saavedra Flores, E. I.; Ajaj, R. M.; Dayyani, I.; Friswell, M. I.

    2014-06-01

    Shape memory alloys (SMAs) are a unique class of metallic materials with the ability to recover their original shape at certain characteristic temperatures (shape memory effect), even under high applied loads and large inelastic deformations, or to undergo large strains without plastic deformation or failure (super-elasticity). In this review, we describe the main features of SMAs, their constitutive models and their properties. We also review the fatigue behavior of SMAs and some methods adopted to remove or reduce its undesirable effects. SMAs have been used in a wide variety of applications in different fields. In this review, we focus on the use of shape memory alloys in the context of morphing aircraft, with particular emphasis on variable twist and camber, and also on actuation bandwidth and reduction of power consumption. These applications prove particularly challenging because novel configurations are adopted to maximize integration and effectiveness of SMAs, which play the role of an actuator (using the shape memory effect), often combined with structural, load-carrying capabilities. Iterative and multi-disciplinary modeling is therefore necessary due to the fluid-structure interaction combined with the nonlinear behavior of SMAs.

  10. Physical applications of GPS geodesy: a review.

    Science.gov (United States)

    Bock, Yehuda; Melgar, Diego

    2016-10-01

    Geodesy, the oldest science, has become an important discipline in the geosciences, in large part by enhancing Global Positioning System (GPS) capabilities over the last 35 years well beyond the satellite constellation's original design. The ability of GPS geodesy to estimate 3D positions with millimeter-level precision with respect to a global terrestrial reference frame has contributed to significant advances in geophysics, seismology, atmospheric science, hydrology, and natural hazard science. Monitoring the changes in the positions or trajectories of GPS instruments on the Earth's land and water surfaces, in the atmosphere, or in space, is important for both theory and applications, from an improved understanding of tectonic and magmatic processes to developing systems for mitigating the impact of natural hazards on society and the environment. Besides accurate positioning, all disturbances in the propagation of the transmitted GPS radio signals from satellite to receiver are mined for information, from troposphere and ionosphere delays for weather, climate, and natural hazard applications, to disturbances in the signals due to multipath reflections from the solid ground, water, and ice for environmental applications. We review the relevant concepts of geodetic theory, data analysis, and physical modeling for a myriad of processes at multiple spatial and temporal scales, and discuss the extensive global infrastructure that has been built to support GPS geodesy consisting of thousands of continuously operating stations. We also discuss the integration of heterogeneous and complementary data sets from geodesy, seismology, and geology, focusing on crustal deformation applications and early warning systems for natural hazards.

  11. Review of Top Quark Physics Results

    Energy Technology Data Exchange (ETDEWEB)

    Kehoe, R.; Narain, M.; Kumar, A.

    2007-12-01

    As the heaviest known fundamental particle, the top quark has taken a central role in the study of fundamental interactions. Production of top quarks in pairs provides an important probe of strong interactions. The top quark mass is a key fundamental parameter which places a valuable constraint on the Higgs boson mass and electroweak symmetry breaking. Observations of the relative rates and kinematics of top quark final states constrain potential new physics. In many cases, the tests available with study of the top quark are both critical and unique. Large increases in data samples from the Fermilab Tevatron have been coupled with major improvements in experimental techniques to produce many new precision measurements of the top quark. The first direct evidence for electroweak production of top quarks has been obtained, with a resulting direct determination of V{sub tb}. Several of the properties of the top quark have been measured. Progress has also been made in obtaining improved limits on potential anomalous production and decay mechanisms. This review presents an overview of recent theoretical and experimental developments in this field. We also provide a brief discussion of the implications for further efforts.

  12. A review of metasurfaces: physics and applications.

    Science.gov (United States)

    Chen, Hou-Tong; Taylor, Antoinette J; Yu, Nanfang

    2016-07-01

    Metamaterials are composed of periodic subwavelength metal/dielectric structures that resonantly couple to the electric and/or magnetic components of the incident electromagnetic fields, exhibiting properties that are not found in nature. This class of micro- and nano-structured artificial media have attracted great interest during the past 15 years and yielded ground-breaking electromagnetic and photonic phenomena. However, the high losses and strong dispersion associated with the resonant responses and the use of metallic structures, as well as the difficulty in fabricating the micro- and nanoscale 3D structures, have hindered practical applications of metamaterials. Planar metamaterials with subwavelength thickness, or metasurfaces, consisting of single-layer or few-layer stacks of planar structures, can be readily fabricated using lithography and nanoprinting methods, and the ultrathin thickness in the wave propagation direction can greatly suppress the undesirable losses. Metasurfaces enable a spatially varying optical response (e.g. scattering amplitude, phase, and polarization), mold optical wavefronts into shapes that can be designed at will, and facilitate the integration of functional materials to accomplish active control and greatly enhanced nonlinear response. This paper reviews recent progress in the physics of metasurfaces operating at wavelengths ranging from microwave to visible. We provide an overview of key metasurface concepts such as anomalous reflection and refraction, and introduce metasurfaces based on the Pancharatnam-Berry phase and Huygens' metasurfaces, as well as their use in wavefront shaping and beam forming applications, followed by a discussion of polarization conversion in few-layer metasurfaces and their related properties. An overview of dielectric metasurfaces reveals their ability to realize unique functionalities coupled with Mie resonances and their low ohmic losses. We also describe metasurfaces for wave guidance and

  13. Physical Environment Correlates of Physical Activity in Developing Countries: A Review.

    Science.gov (United States)

    Day, Kristen

    2018-04-01

    Noncommunicable diseases and obesity are considered problems of wealthy, developed countries. These conditions are rising dramatically in developing countries. Most existing research on the role of the physical environment to support physical activity examines developed countries only. This review identifies physical environment factors that are associated with physical activity in developing countries. This review is modeled on a highly cited review by Saelens and Handy in 2008. The current review analyzes findings from 159 empirical studies in the 138 developing countries. Results discuss the association of physical environment features and physical activity for all developing countries and identify the patterns within regions. The review supports the association of traffic safety with physical activity for transportation. Rural (vs urban) residence, distance to nonresidential land uses, and "composite" features of the physical environment are associated with general physical activity. Rural (vs urban) residence is associated with physical activity for work. More research is needed on associations between the physical environment and physical activity in developing countries. Research should identify specific physical environment features in urban areas that are associated with higher activity levels.

  14. 78 FR 29780 - Proposal Review Panel Physics; Notice of Meeting

    Science.gov (United States)

    2013-05-21

    ... Proposal Review Panel Physics; Notice of Meeting In accordance with the Federal Advisory Committee Act (Pub... for Nuclear Physics; National Science Foundation, 4201 Wilson Blvd., Arlington, VA 22230. Telephone..., Operations, Upgrades and Commissioning Overview 10:15 a.m.-11:15 a.m. Open--Accelerator Physics Research, and...

  15. Understanding the physical metallurgy of the CoCrFeMnNi high-entropy alloy: an atomistic simulation study

    Science.gov (United States)

    Choi, Won-Mi; Jo, Yong Hee; Sohn, Seok Su; Lee, Sunghak; Lee, Byeong-Joo

    2018-01-01

    Although high-entropy alloys (HEAs) are attracting interest, the physical metallurgical mechanisms related to their properties have mostly not been clarified, and this limits wider industrial applications, in addition to the high alloy costs. We clarify the physical metallurgical reasons for the materials phenomena (sluggish diffusion and micro-twining at cryogenic temperatures) and investigate the effect of individual elements on solid solution hardening for the equiatomic CoCrFeMnNi HEA based on atomistic simulations (Monte Carlo, molecular dynamics and molecular statics). A significant number of stable vacant lattice sites with high migration energy barriers exists and is thought to cause the sluggish diffusion. We predict that the hexagonal close-packed (hcp) structure is more stable than the face-centered cubic (fcc) structure at 0 K, which we propose as the fundamental reason for the micro-twinning at cryogenic temperatures. The alloying effect on the critical resolved shear stress (CRSS) is well predicted by the atomistic simulation, used for a design of non-equiatomic fcc HEAs with improved strength, and is experimentally verified. This study demonstrates the applicability of the proposed atomistic approach combined with a thermodynamic calculation technique to a computational design of advanced HEAs.

  16. Eating Disorders, Physical Fitness and Sport Performance: A Systematic Review

    OpenAIRE

    El Ghoch, Marwan; Soave, Fabio; Calugi, Simona; Dalle Grave, Riccardo

    2013-01-01

    Background: Eating disorders are health problems that are particularly prevalent in adolescents and young adults. They are associated with considerable physical health and psychosocial morbidity, and increased risk of mortality. We set out to conduct a systematic review to determine their effect on physical fitness in the general population and on sport performance in athletes. Methods/Design: A systematic review of the relevant peer-reviewed literature was performed. For inclusion, articles ...

  17. Review of Physics Results from the Tevatron: Top Quark Physics

    Energy Technology Data Exchange (ETDEWEB)

    Gerber, Cecilia E.; Vellidis, Costas

    2014-09-17

    We present results on top quark physics from the CDF and D0 collaborations at the Fermilab Tevatron proton anti-proton collider. These include legacy results from Run II that were published or submitted for publication before mid-2014, as well as a summary of Run I results. The historical perspective of the discovery of the top quark in Run I is also described.

  18. Correlates of Physical Activity in Asian Adolescents: A Literature Review

    Directory of Open Access Journals (Sweden)

    Husna Hidayati

    2012-08-01

    Full Text Available Background: Physical activity is important to prevent several chronic diseases in adulthood. Nowadays, young people do not regularly perform physical activity. Several factors may influence their decision. Most of studies were conducted in western countries. However the findings might not be generalized regarding the differences in culture and social condition. Therefore, reviewing the correlates of physical activity among adolescents in Asian countries is essential. Purpose: To update the state of knowledge on factors associated with adolescents’ physical activity in Asian countries. Methods: Literature review on existing articles retrieved from electronic databases was conducted. The review on factors of physical activity was set based on the setting of study, adolescents as participants of the study and the year of publication ranged from 2002-2011. Result: The findings compiled the evidence of relationships between physical activity and several influencing factors. Intrapersonal factors age, gender, socioeconomic status, parental education, and perceptions related to physical activity- perceived self efficacy, perceived benefits, and perceived barriers, interpersonal factors (family and peer influences and extra-personal factors (school policy and living arrangement were identified. Self efficacy was manifested as the strongest influencing factor in most studies. This review highlighted the cultural issues on physical activities of adolescents in Asian countries. Conclusion: This paper provided comprehensive knowledge related to factors influencing physical activity in Asian adolescents. The issue of cultural sensitivity should be considered in the future intervention program designed to improve physical activity of adolescents. Keyword: adolescent, physical activity, health Promotion, Asian countries

  19. A brief review of cavity swelling and hardening in irradiated copper and copper alloys

    International Nuclear Information System (INIS)

    Zinkle, S.J.

    1990-01-01

    The literature on radiation-induced swelling and hardening in copper and its alloy is reviewed. Void formation does not occur during irradiation of copper unless suitable impurity atoms such as oxygen or helium are present. Void formation occurs for neutron irradiation temperatures of 180 to 550 degree C, with peak swelling occurring at ∼320 degree C for irradiation at a damage rate of 2 x 10 -7 dpa/s. The post-transient swelling rate has been measured to be ∼0.5%/dpa at temperatures near 400 degree C. Dispersion-strengthened copper has been found to be very resistant to void swelling due to the high sink density associated with the dispersion-stabilized dislocation structure. Irradiation of copper at temperatures below 400 degree C generally causes an increase in strength due to the formation of defect clusters which inhibit dislocation motion. The radiation hardening can be adequately described by Seeger's dispersed barrier model, with a barrier strength for small defect clusters of α ∼ 0.2. The radiation hardening apparently saturates for fluences greater than ∼10 24 n/m 2 during irradiation at room temperature due to a saturation of the defect cluster density. Grain boundaries can modify the hardening behavior by blocking the transmission of dislocation slip bands, leading to a radiation- modified Hall-Petch relation between yield strength and grain size. Radiation-enhanced recrystallization can lead to softening of cold-worked copper alloys at temperatures above 300 degree C

  20. The statistical physics of multi-component alloys using KKR-CPA

    Science.gov (United States)

    Khan, Suffian; Staunton, J. B.; Stocks, G. M.

    We apply the Landau theory of phase transitions to multicomponent alloys using the multiple-scattering theory of Korringa-Kohn-Rostoker (KKR) and the coherent potential approximation (CPA). This theory is a multicomponent generalization of the S (2) theory of binary alloys developed by G. M. Stocks, J. B. Staunton, D. D. Johnson and others. It is highly relevant to the chemical phase stability of high-entropy alloys as it predicts the kind and size of finite-temperature chemical fluctuations of a disordered alloy. In doing so it includes effects of charge-rearrangements and other electronics due to changing site occupancies. When chemical fluctuations grow without bound an absolute instability occurs and a second-order order-disorder phase transition may be inferred. The theory lends itself to a natural interpretation in terms of competing effects: entropy driving disorder and favorable pair interactions driving atomic ordering. To further clarify interpretation we present results for the representative ternary alloys CuAgAu, NiPdPt, RhPdAg, and CoNiCu. This work was supported by the Materials Sciences & Engineering Division of the Office of Basic Energy Sciences, U.S. Department of Energy.

  1. Review: Microstructure Engineering of Titanium Alloys via Small Boron Additions (Preprint)

    Science.gov (United States)

    2011-07-01

    cast Ti alloys with the motivation of enhancing mechanical properties for dental applications. They observed significant grain refinement which was...Addition of inoculants to many molten metal alloys (e.g. trace B to Al alloys [17]) is the most commonly used commercial practice to achieve grain... metallic inclusions were the life limiting mechanisms in the pre- alloyed powder Ti-64B material, especially in two outlier data points with life less than

  2. Built environmental correlates of physical activity in China: A review.

    Science.gov (United States)

    Day, Kristen

    2016-06-01

    China faces growing levels of physical inactivity and obesity, associated with increasing urbanization and changing lifestyles in recent years. China is expanding its cities to accommodate a growing urban population. This paper identifies built environment factors that are associated with physical activity in China. Findings can inform urban design and development in China to support increased physical activity. This paper is modeled on a review of built environment correlates of walking by Saelens and Handy (2008). Saelens and Handy reviewed research in developed countries. The present paper reviews 42 empirical studies that were conducted in China and were published between 2006 and 2014. Results discuss the association of built environment features and physical activity for transportation, recreation and work. Studies focus on adults and on major cities. Data on the built environment is typically self-reported. Strongest evidence was found for the positive association of physical activity with proximal non-residential locations, pedestrian infrastructure, aesthetics, and non-park physical activity facilities, and for the negative association of physical activity with urban residence. In terms of physical activity for transportation, evidence is strongest for associations between physical activity for transportation and proximal non-residential locations. More research is needed on the built environment and physical activity, especially including research on significant features of Chinese cities, such as air pollution, high density levels, traffic safety, and others. Research on associations between built environment features and physical activity should consider the specific social and built environment contexts of Chinese cities.

  3. Book Review: Physics of the Space Environment

    Science.gov (United States)

    Holman, Gordon D.

    1998-01-01

    Space physics, narrowly defined as the study of Earth's plasma environment, has had an identity crisis throughout its relatively brief existence as a discipline. - The limited and often serendipitous nature of the data requires the research style of an astrophysicist. However, the in situ observations and instrumentation that are central to the field are quite different from the remote observations and instrumentation of astronomy. Compared to neutral gases, the wealth of additional phenomena and the complexity associated with magnetized plasmas and their interaction leaves little in common with the atmospheric scientist. Although the phenomena studied in space physics are ultimately important to astrophysics, the intimate measurements of plasma properties provide a greater commonality with the plasma physicist. Space physics has experienced something of a renaissance in the past few years. The interdisciplinary umbrella "Solar-Terrestrial Physics" or "Sun-Earth Connection" has stimulated an increasing interaction of space physicists, solar physicists and atmospheric scientists. Spectacular images of the Sun from Yohkoh and SOHO and solar-activity-related damage to communications satellites have increased the public's awareness of and interest in "space weather". The dangers of energetic particles and currents in space to technological systems and to future space exploration have elevated space physics observations from interesting scientific measurements that can be included on a space probe to critically important measurements that must be made.

  4. Effect of sintering temperature on physical properties & hardness of CoCrMo alloys fabricated by metal injection moulding process

    Science.gov (United States)

    Ridhwan Abdullah, Ahmad; Aidah Nabihah Dandang, Nur; Zalikha Khalil, Nur; Harun, Wan Sharuzi Wan

    2017-10-01

    Metal Injection Moulding (MIM) process is one of the Powder Metallurgy manufacturing techniques utilised to produce Cobalt Chromium Molybdenum (CoCrMo) compacts. The objective of this study is to determine physical properties and hardness of CoCrMo alloy compact sintered at three different sintering temperature at the similar soaking time. At the beginning, sample were fabricated by using Injection Moulding machine. Cobalt Chrome Molybdenum (CoCrMo) metal powder was selected for this study. A morphological study was conducted using optical microscope (OM) and micro-Vickers hardness testing. From the result obtained, it shows upward trend either on the hardness or physical properties of the samples. CoCrMo sintered compact become harder and volume of pores on surface become less due to the increase on sintering temperature. However, effect of increasing sintering temperature shows significant shrinkage of the sample, beginning losses in dimensional accuracy. It is discovered that a little change in sintering temperature gives significant impact on the microstructure, physical, mechanical of the alloy.

  5. Microstructure and Properties of Semi-Solid Aluminum Alloys: A Literature Review

    Directory of Open Access Journals (Sweden)

    Annalisa Pola

    2018-03-01

    Full Text Available Semi-solid processing of aluminum alloys is a well-known manufacturing technique able to combine high production rates with parts quality, resulting in high performance and reasonable component costs. The advantages offered by semi-solid processing are due to the shear thinning behavior of the thixotropic slurries during the mold filling. This is related to the microstructure of these slurries consisting of solid, nondendritic, near-globular primary particles surrounded by a liquid matrix. This paper presents a review on the formation of this nondendritic microstructure, reports on the different proposed mechanisms that might be responsible, and illustrates the relationship between microstructure and properties, in particular, tensility, fatigue, wear, and corrosion resistance.

  6. Tribochemical Characterization and Tribocorrosive Behavior of CoCrMo Alloys: A Review.

    Science.gov (United States)

    Toh, Wei Quan; Tan, Xipeng; Bhowmik, Ayan; Liu, Erjia; Tor, Shu Beng

    2017-12-26

    Orthopedic implants first started out as an all-metal hip joint replacement. However, poor design and machinability as well as unsatisfactory surface finish subjected the all-metal joint replacement to being superseded by a polyethylene bearing. Continued improvement in manufacturing techniques together with the reality that polyethylene wear debris can cause hazardous reactions in the human body has brought about the revival of metal-on-metal (MOM) hip joints in recent years. This has also led to a relatively new research area that links tribology and corrosion together. This article aims at reviewing the commonly used tribochemical methods adopted in the analysis of tribocorrosion and putting forward some of the models and environmental factors affecting the tribocorrosive behavior of CoCrMo alloys, a widely-used class of biomaterial for orthopedic implants.

  7. Tribochemical Characterization and Tribocorrosive Behavior of CoCrMo Alloys: A Review

    Directory of Open Access Journals (Sweden)

    Wei Quan Toh

    2017-12-01

    Full Text Available Orthopedic implants first started out as an all-metal hip joint replacement. However, poor design and machinability as well as unsatisfactory surface finish subjected the all-metal joint replacement to being superseded by a polyethylene bearing. Continued improvement in manufacturing techniques together with the reality that polyethylene wear debris can cause hazardous reactions in the human body has brought about the revival of metal-on-metal (MOM hip joints in recent years. This has also led to a relatively new research area that links tribology and corrosion together. This article aims at reviewing the commonly used tribochemical methods adopted in the analysis of tribocorrosion and putting forward some of the models and environmental factors affecting the tribocorrosive behavior of CoCrMo alloys, a widely-used class of biomaterial for orthopedic implants.

  8. Nurses' occupational physical activity levels: A systematic review.

    Science.gov (United States)

    Chappel, Stephanie E; Verswijveren, Simone J J M; Aisbett, Brad; Considine, Julie; Ridgers, Nicola D

    2017-08-01

    Nurses' physical performance at work has implications both for nurses' occupational health and patient care. Although nurses are the largest healthcare workforce, are present 24-hours a day, and engage in many physically demanding tasks, nurses' occupational physical activity levels are poorly understood. The aim of this systematic review was to examine nurses' occupational physical activity levels, and explore how nurses accumulate their physical activity during a shift. This narrative systematic review was guided by the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) Statement. EBSCOHost (MEDLINE, CINAHL, Age Line, Academic Search Complete, Global Health, Health Business Centre, Health Policy Reference Centre, Health Source (Consumer and Nursing/Academic Edition) and SPORTDiscus), Embase, Informit, ProQuest Health and Medical, Science Direct, Scopus, and Web of Science databases. A systematic search of seven databases were completed to locate peer-reviewed journal articles documenting nurses' occupational physical activity levels from January 1990. Papers were included if they were original research papers; measured physical activity objectively and/or subjectively; reported nurses' occupational physical activity; and were published in English. Articles were excluded if nurses' data were not reported separately from other professional groups. Two researchers independently screened the articles, extracted data, and undertook the methodological quality assessments. Fifteen studies met the inclusion criteria. Nursing work predominantly comprised of light-intensity physical activity. In nine studies how nurses' accumulated occupational physical activity were documented and showed that the majority of a nurses' shift was spent standing or walking whilst completing direct patient care tasks. However, the definition of the nursing populations studied were often poorly reported, and few researchers reported the validity and the reliability of

  9. Physical activity in advanced cancer patients: a systematic review protocol.

    Science.gov (United States)

    Lowe, Sonya S; Tan, Maria; Faily, Joan; Watanabe, Sharon M; Courneya, Kerry S

    2016-03-11

    Progressive, incurable cancer is associated with increased fatigue, increased muscle weakness, and reduced physical functioning, all of which negatively impact quality of life. Physical activity has demonstrated benefits on cancer-related fatigue and physical functioning in early-stage cancer patients; however, its impact on these outcomes in end-stage cancer has not been established. The aim of this systematic review is to determine the potential benefits, harms, and effects of physical activity interventions on quality of life outcomes in advanced cancer patients. A systematic review of peer-reviewed literature on physical activity in advanced cancer patients will be undertaken. Empirical quantitative studies will be considered for inclusion if they present interventional or observational data on physical activity in advanced cancer patients. Searches will be conducted in the following electronic databases: CINAHL; CIRRIE Database of International Rehabilitation Research; Cochrane Database of Systematic Reviews (CDSR); Database of Abstracts of Reviews of Effects (DARE); Cochrane Central Register of Controlled Trials (CENTRAL); EMBASE; MEDLINE; PEDro: the Physiotherapy Evidence Database; PQDT; PsycInfo; PubMed; REHABDATA; Scopus; SPORTDiscus; and Web of Science, to identify relevant studies of interest. Additional strategies to identify relevant studies will include citation searches and evaluation of reference lists of included articles. Titles, abstracts, and keywords of identified studies from the search strategies will be screened for inclusion criteria. Two independent reviewers will conduct quality appraisal using the Effective Public Health Practice Project Quality Assessment Tool for Quantitative Studies (EPHPP) and the Cochrane risk of bias tool. A descriptive summary of included studies will describe the study designs, participant and activity characteristics, and objective and patient-reported outcomes. This systematic review will summarize the current

  10. Review of Physics Results from the Tevatron: Higgs Boson Physics

    International Nuclear Information System (INIS)

    Junk, Thomas R.; Juste, Aurelio

    2015-01-01

    We review the techniques and results of the searches for the Higgs boson performed by the two Tevatron collaborations, CDF and DO. The Higgs boson predicted by the Standard Model was sought in the mass range 90 GeV

  11. Physics Division annual review, April 1, 1992--March 31, 1993

    International Nuclear Information System (INIS)

    Thayer, K.J.

    1993-08-01

    This document is the annual review of the Argonne National Laboratory Physics Division for the period April 1, 1992--March 31, 1993. Work on the ATLAS device is covered, as well as work on a number of others in lab, as well as collaborative projects. Heavy ion nuclear physics research looked at quasi-elastic, and deep-inelastic reactions, cluster states, superdeformed nuclei, and nuclear shape effects. There were programs on accelerator mass spectroscopy, and accelerator and linac development. There were efforts in medium energy nuclear physics, weak interactions, theoretical nuclear and atomic physics, and experimental atomic and molecular physics based on accelerators and synchrotron radiation

  12. Physics Division annual review, April 1, 1992--March 31, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Thayer, K.J. [ed.

    1993-08-01

    This document is the annual review of the Argonne National Laboratory Physics Division for the period April 1, 1992--March 31, 1993. Work on the ATLAS device is covered, as well as work on a number of others in lab, as well as collaborative projects. Heavy ion nuclear physics research looked at quasi-elastic, and deep-inelastic reactions, cluster states, superdeformed nuclei, and nuclear shape effects. There were programs on accelerator mass spectroscopy, and accelerator and linac development. There were efforts in medium energy nuclear physics, weak interactions, theoretical nuclear and atomic physics, and experimental atomic and molecular physics based on accelerators and synchrotron radiation.

  13. Book Review: Space Weather: Physics and Effects

    Science.gov (United States)

    Wilkinson, Phil

    2007-11-01

    At 438 pages, Space Weather: Physics and Effects, edited by Volker Bothmer and Ioannis A. Daglis, seems like a daunting read. But its thickness belies its conversational tone, and its content provides a different presentation of material aimed at drawing in a new audience while satisfying the present space weather audience's interest in their subject. I found reading this book a pleasure.

  14. Recent physics at COSY – A review

    Indian Academy of Sciences (India)

    interest are COSY-11, ANKE and EDDA internally and TOF and BIG KARL externally. The physics at EDDA, proton–proton scattering of unpolarised on un- polarised, polarised on unpolarised and polarised on polarised [1] is terminated and is therefore neglected here. COSY-11 and ANKE are magnetic detectors. The.

  15. 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.

  16. Integration and Physical Education: A Review of Research

    Science.gov (United States)

    Marttinen, Risto Harri Juhani; McLoughlin, Gabriella; Fredrick, Ray, III; Novak, Dario

    2017-01-01

    The Common Core State Standards Initiative has placed an increased focus on mathematics and English language arts. A relationship between physical activity and academic achievement is evident, but research on integration of academic subjects with physical education is still unclear. This literature review examined databases for the years…

  17. Review of lattice results concerning low-energy particle physics

    DEFF Research Database (Denmark)

    Aoki, Sinya; Aoki, Yasumichi; Bečirević, D.

    2017-01-01

    We review lattice results related to pion, kaon, D- and B-meson physics with the aim of making them easily accessible to the particle-physics community. More specifically, we report on the determination of the light-quark masses, the form factor f+(0) , arising in the semileptonic K→ π transition...

  18. Review of lattice results concerning low energy particle physics

    DEFF Research Database (Denmark)

    Aoki, Sinya; Aoki, Yasumichi; Bernard, Claude

    2014-01-01

    We review lattice results related to pion, kaon, D- and B-meson physics with the aim of making them easily accessible to the particle physics community. More specifically, we report on the determination of the light-quark masses, the form factor f+(0), arising in semileptonic K -> pi transition a...

  19. BOOK REVIEW: Fundamentals of Plasma Physics

    Science.gov (United States)

    Cargill, P. J.

    2007-02-01

    The widespread importance of plasmas in many areas of contemporary physics makes good textbooks in the field that are both introductory and comprehensive invaluable. This new book by Paul Bellen from CalTech by and large meets these goals. It covers the traditional textbook topics such as particle orbits, the derivation of the MHD equations from Vlasov theory, cold and warm plasma waves, Landau damping, as well as in the later chapters less common subjects such as magnetic helicity, nonlinear processes and dusty plasmas. The book is clearly written, neatly presented, and each chapter has a number of exercises or problems at their end. The author has also thankfully steered clear of the pitfall of filling the book with his own research results. The preface notes that the book is designed to provide an introduction to plasma physics for final year undergraduate and post-graduate students. However, it is difficult to see many physics undergraduates now at UK universities getting to grips with much of the content since their mathematics is not of a high enough standard. Students in Applied Mathematics departments would certainly fare better. An additional problem for the beginner is that some of the chapters do not lead the reader gently into a subject, but begin with quite advanced concepts. Being a multi-disciplinary subject, beginners tend to find plasma physics quite hard enough even when done simply. For postgraduate students these criticisms fade away and this book provides an excellent introduction. More senior researchers should also enjoy the book, especially Chapters 11-17 where more advanced topics are discussed. I found myself continually comparing the book with my favourite text for many years, `The Physics of Plasmas' by T J M Boyd and J J Sanderson, reissued by Cambridge University Press in 2003. Researchers would want both books on their shelves, both for the different ways basic plasma physics is covered, and the diversity of more advanced topics. For

  20. <REVIEW ARTICLE>Current Trends in Physical Anthropology in Japan

    OpenAIRE

    HANIHARA, Kazuro

    1992-01-01

    The trends in physical anthropology in Japan have largely changed through the introduction of new methodologies such as molecular genetics and multivariate statistics in the 1960s. The development of ecology and primatology brought another new wave into the field of physical anthropology. This paper reviews briefly general trends in research in physical anthropology now on-going in Japan. Microevolutionary studies of the Japanese and neighboring populations which have a long history in Jap...

  1. A Review on Recent Developments and Prospects for Oxygen Reduction Reaction on Hollow Pt-alloy Nanoparticles.

    Science.gov (United States)

    Asset, Tristan; Chattot, Raphaël; Fontana, Marie; Mercier-Guyon, Benjamin; Job, Nathalie; Dubau, Laetitia; Maillard, Frederic

    2018-03-26

    Due to their interesting electrocatalytic properties for the oxygen reduction reaction (ORR), hollow Pt-alloy nanoparticles (NPs) supported on high surface area carbon attract growing interest. However, the suitable synthesis methods and associated mechanisms of formation, the reasons for their enhanced specific activity for the ORR, and the nature of adequate alloy-ing elements and carbon supports for this type of nanocatalysts remain open questions. This review aims at shedding light on these topics with a special emphasis on hollow PtNi NPs supported onto Vulcan XC72 (PtNi/C). We first show how hollow Pt-alloy/C can be synthe-sized by a mechanism involving galvanic replacement and the nanoscale Kirkendall effect. Nickel, cobalt, copper, zinc and iron (Ni, Co, Cu, Zn, and Fe, respectively) were tested for the formation of Pt-alloy/C hollow nanostructures. Our results indicate that metals with standard potential - 0.4 PEMFC cathode operating conditions, the beneficial effect of structural disorder is maintained on the long term, thereby bringing promises for the synthesis of highly active and robust ORR electrocatalysts. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Development of Ag-Pd-Au-Cu alloy for multiple dental applications. Part 1. Effects of Pd and Cu contents, and addition of Ga or Sn on physical properties and bond with ultra-low fusing ceramic.

    Science.gov (United States)

    Goto, S; Miyagawa, Y; Ogura, H

    2000-09-01

    Ag-Pd-Au-Cu quaternary alloys consisting of 30-50% Ag, 20-40% Pd, 10-20% Cu and 20% Au (mother alloys) were prepared. Then 5% Sn or 5% Ga was added to the mother alloy compositions, and another two alloy systems (Sn-added alloys and Ga-added alloys) were also prepared. The bond between the prepared alloys and an ultra-low fusing ceramic as well as their physical properties such as the solidus point, liquidus point and the coefficient of thermal expansion were evaluated. The solidus point and liquidus point of the prepared alloys ranged from 802 degrees C to 1142 degrees C and from 931 degrees C to 1223 degrees C, respectively. The coefficient of thermal expansion ranged from 14.6 to 17.1 x 10(-6)/degrees C for the Sn- and Ga-added alloys. In most cases, the Pd and Cu contents significantly influenced the solidus point, liquidus point and coefficient of thermal expansion. All Sn- and Ga-added alloys showed high area fractions of retained ceramic (92.1-100%), while the mother alloy showed relatively low area fractions (82.3%) with a high standard deviation (20.5%). Based on the evaluated properties, six Sn-added alloys and four Ga-added alloys among the prepared alloys were suitable for the application of the tested ultra-low fusing ceramic.

  3. BOOK REVIEW: Modern Physics, 3rd edn

    Science.gov (United States)

    Lovett, David

    1999-09-01

    The number of broadly based physics texts written at a level corresponding to second year and above of UK physics degrees is limited. This is such a book thoroughly updated in a third edition, the first edition having been published 20 years ago. The book is unusual in that the reader is referred to the Freeman website www.whfreeman.com/physics for some additional sections. It will be interesting to see whether this proves to be an attractive feature. The coverage reflects the US emphasis on topics and contains both theoretical and experimental details. It should not be regarded as an introductory text although it is clearly written. Thus the first two chapters take the reader straight into relativity, concentrating mainly on special relativity but going on to general relativity. From here the reader is led to ideas of quantization of charge, light and energy, followed by an exploration of the nuclear atom, wavelike properties of particles and Schrödinger's equation. Solution of this equation for the hydrogen atom introduces a section on spectroscopy. The next chapter on statistical physics includes Fermi-Dirac and Bose-Einstein statistics and brings to a close Part 1, which concentrates on the theoretical groundwork. Consistent with its title, the book does not cover traditional aspects of thermodynamics and electromagnetic theory. Part 2 is entitled `Applications' and begins with a chapter on molecular structure and spectra. Lasers and masers are included here but geometrical, physical and nonlinear optics get limited or no coverage. Solid state physics follows but, despite the title of the book, there is little on modern devices, although the section on superconductivity mentions high temperature materials. The chapters on nuclear physics, fission, fusion reactors and medical applications and a chapter on particle physics are comprehensive. Finally a chapter on astrophysics and cosmology is referred to, but the reader must find this at the website. As this is

  4. Workplace physical activity interventions: a systematic review.

    Science.gov (United States)

    To, Quyen G; Chen, Ted T L; Magnussen, Costan G; To, Kien G

    2013-01-01

    To assess the effectiveness of workplace interventions in improving physical activity. EBSCO research database (and all subdatabases). Articles were published from 2000 to 2010 in English, had appropriate designs, and measured employees' physical activity, energy consumption, and/or body mass index (BMI) as primary outcomes. Articles that did not meet the inclusion criteria were excluded. Data extracted included study design, study population, duration, intervention activities, outcomes, and results. Data were synthesized into one table. Results of each relevant outcome including p values were combined. Twelve (60%) of 20 selected interventions reported an improvement in physical activity level, steps, or BMI, and there was one slowed step reduction in the intervention group. Among these, 10 were less than 6 months in duration; 9 used pedometers; 6 applied Internet-based approaches; and 5 included activities targeting social and environmental levels. Seven of 8 interventions with pre-posttest and quasi-experimental controlled design showed improvement on at least one outcome. However, 7 of 12 randomized controlled trials (RCTs) did not prove effective in any outcome. Interventions that had less rigorous research designs, used pedometers, applied Internet-based approaches, and included activities at social and environmental levels were more likely to report being effective than those without these characteristics.

  5. Review of the early AP penetrator work at LASL which led to the selection of U-3/4 Ti alloy

    International Nuclear Information System (INIS)

    Sandstrom, D.J.

    1976-01-01

    A historical review is presented of the depleted uranium penetrator work. The following alloys were studied: U--Ti, U--Mo, U--Nb, and U--Nb--Ti. Ballistic properties, armor penetration, and corrosion resistance were studied. The U--Ti alloy was found to offer the best combination of properties. 12 figures

  6. Accelerators, Beams And Physical Review Special Topics - Accelerators And Beams

    Energy Technology Data Exchange (ETDEWEB)

    Siemann, R.H.; /SLAC

    2011-10-24

    Accelerator science and technology have evolved as accelerators became larger and important to a broad range of science. Physical Review Special Topics - Accelerators and Beams was established to serve the accelerator community as a timely, widely circulated, international journal covering the full breadth of accelerators and beams. The history of the journal and the innovations associated with it are reviewed.

  7. Inclusion in Physical Education: A Review of Literature

    Science.gov (United States)

    Qi, Jing; Ha, Amy S.

    2012-01-01

    The purpose of this review was to analyse empirical studies on inclusion in physical education (PE) over the past 20 years and then propose recommendations for future research. A systematic process was used to search the literature for this review. First, a total of 75 research-based articles from computerised education databases were included in…

  8. AN EFFECT OF SHOT PEENING ON GROWTH AND RETARDATION OF PHYSICALLY SHORT FATIGUE CRACKS IN AN AIRCRAFT Al-ALLOY

    Directory of Open Access Journals (Sweden)

    Ivo Černý

    2009-11-01

    Full Text Available Results of an investigation of effect of shot peening on development of physically short fatigue crack in an aircraft V-95 Al-alloy, which is of a similar type as 7075 alloy, are described and discussed in the paper. The first part deals with adaptation and verification of direct current potential drop method for detection and measurement of short crack initiation and growth. The specific material and quite large dimensions of flat specimens with side necking of a low stress concentration factor had to be considered when position of electrodes was specified and the measurement method verified. The specimen type and dimensions were proposed taking account of the investigation of shot peening effects. Physically short fatigue cracks of the length from 0.2 mm to more than 3 mm, most of them between 0.8 – 1.5 mm, were prepared under high cycle fatigue loading of a constant nominal stress amplitude plus/minus 160 MPa. Specimens with existing short fatigue cracks were shot peened using two different groups of parameters. Development of crack growth after shot peening was measured and compared with crack growth in specimens without shot peening. Retardation of crack growth was significant particularly with cracks shorter than 2 mm. For the specific stress amplitude, evaluated results enable to estimate threshold length of defects, which after the application of shot peening will be reliably arrested.

  9. Correlates associated with participation in physical activity among adults: a systematic review of reviews and update

    Directory of Open Access Journals (Sweden)

    Jaesung Choi

    2017-04-01

    Full Text Available Abstract Background Understanding which factors influence participation in physical activity is important to improve the public health. The aim of the present review of reviews was to summarize and present updated evidence on personal and environmental factors associated with physical activity. Methods MEDLINE and EMBASE were searched for reviews published up to 31 Jan. 2017 reporting on potential factors of physical activity in adults aged over 18 years. The quality of each review was appraised with the Assessing the Methodological Quality of Systematic Reviews (AMSTAR checklist. The corrected covered area (CCA was calculated as a measure of overlap for the primary publications in each review. Results Twenty-five articles met the inclusion criteria which reviewed 90 personal and 27 environmental factors. The average quality of the studies was moderate, and the CCA ranged from 0 to 4.3%. For personal factors, self-efficacy was shown as the strongest factor for participation in physical activity (7 out of 9. Intention to exercise, outcome expectation, perceived behavioral control and perceived fitness were positively associated with physical activity in more than 3 reviews, while age and bad status of health or fitness were negatively associated with participation in physical activity in more than 3 reviews. For environmental factors, accessibility to facilities, presence of sidewalks, and aesthetics were positively associated with participation in physical activity. Conclusions The findings of this review of reviews suggest that some personal and environmental factors were related with participation in physical activity. However, an association of various factors with physical activity could not be established because of the lack of primary studies to build up the organized evidence. More studies with a prospective design should be conducted to understand the potential causes for physical activity.

  10. BOOK REVIEW: Quantum Physics in One Dimension

    Science.gov (United States)

    Logan, David

    2004-05-01

    To a casual ostrich the world of quantum physics in one dimension may sound a little one-dimensional, suitable perhaps for those with an unhealthy obsession for the esoteric. Nothing of course could be further from the truth. The field is remarkably rich and broad, and for more than fifty years has thrown up innumerable challenges. Theorists, realising that the role of interactions in 1D is special and that well known paradigms of higher dimensions (Fermi liquid theory for example) no longer apply, took up the challenge of developing new concepts and techniques to understand the undoubted pecularities of one-dimensional systems. And experimentalists have succeeded in turning pipe dreams into reality, producing an impressive and ever increasing array of experimental realizations of 1D systems, from the molecular to the mesoscopic---spin and ladder compounds, organic superconductors, carbon nanotubes, quantum wires, Josephson junction arrays and so on. Many books on the theory of one-dimensional systems are however written by experts for experts, and tend as such to leave the non-specialist a touch bewildered. This is understandable on both fronts, for the underlying theoretical techniques are unquestionably sophisticated and not usually part of standard courses in many-body theory. A brave author it is then who aims to produce a well rounded, if necessarily partial, overview of quantum physics in one dimension, accessible to a beginner yet taking them to the edge of current research, and providing en route a thorough grounding in the fundamental ideas, basic methods and essential phenomenology of the field. It is of course the brave who succeed in this world, and Thierry Giamarchi does just that with this excellent book, written by an expert for the uninitiated. Aimed in particular at graduate students in theoretical condensed matter physics, and assumimg little theoretical background on the part of the reader (well just a little), Giamarchi writes in a refreshingly

  11. Low activation vanadium alloys

    International Nuclear Information System (INIS)

    Witzenburg, W. van.

    1991-01-01

    The properties and general characteristics of vanadium-base alloys are reviewed in terms of the materials requirements for fusion reactor first wall and blanket structures. In this review attention is focussed on radiation response including induced radioactivity, mechanical properties, compatibility with potential coolants, physical and thermal properties, fabricability and resources. Where possible, properties are compared to those of other leading candidate structural materials, e.g. austenitic and ferritic/martensitic steels. Vanadium alloys appear to offer advantages in the areas of long-term activation, mechanical properties at temperatures above 600 deg C, radiation resistance and thermo-hydraulic design, due to superior physical and thermal properties. They also have a potential for higher temperature operation in liquid lithium systems. Disadvantages are associated with their ability to retain high concentrations of hydrogen isotopes, higher cost, more difficult fabrication and welding. A particular concern regarding use of vanadium alloys relates their reactivity with non-metallic elements, such as oxygen and nitrogen. (author). 33 refs.; 2 figs.; 2 tabs

  12. Physical Exercise and Physical Activity for Children and Adolescents With Juvenile Idiopathic Arthritis: A Literature Review.

    Science.gov (United States)

    Catania, Hilenia; Fortini, Viola; Cimaz, Rolando

    2017-07-01

    This is a review of studies that investigate the efficacy of exercise therapy and physical activity for children with juvenile idiopathic arthritis since the 2008 Cochrane Review. Studies were identified that investigated the use of physical activity and exercise therapy in the treatment of children and adolescents with juvenile idiopathic arthritis, excluding the Cochrane Review. Two reviewers individually analyzed the results of the search to determine the eligibility of studies. The randomized controlled trial study designs were evaluated using PEDro scales. Recent literature supports the importance of the combination of strengthening, stretching, proprioceptive, and balance exercises and activities in water. Many of the reviewed studies proposed an intensive program of physical activity and exercise therapy, conducted 3 times a week for 12 weeks.

  13. Nanoparticles from Cu-Zn-Al shape memory alloys physically synthesized by ion milling deposition

    Energy Technology Data Exchange (ETDEWEB)

    Pavon, Luis Alberto Lopez [Universidad Autonoma de Nuevo Leon (UANL), Nuevo Leon (Mexico); Cuellara, Enrique Lopez; Castro, Alejandro Torres; Cruza, Azael Martinez de la [Universidad Autonoma de Nuevo Leon (CIIDIT/UANL), Nuevo Leon (Mexico). Centro de Innovacion, Investigacion y Desarrollo en Ingenieria y Tecnologia; Ballesteros, Carmen [Universidad Carlos III de Madrid, Madrid (Spain). Departamento de Fisica; Araujo, Carlos Jose de [Universidade Federal de Campina Grande (UFCG), Campina Grande, PB (Brazil). Departamento de Engenharia Mecanica

    2012-05-15

    In this research, an ion milling equipment was used to elaborate nanoparticles from Cu-Zn-Al alloys with shape memory effect. Two different compositions were used, target A: 75.22Cu-17.12Zn-7.66Al at % with an Ms of -9 deg C and target B: 76.18Cu-15.84Zn-7.98Al with an Ms of 20 degree C. Nanoparticles were characterized by High Resolution Transmission Electron Microscopy, Electron Diffraction and Energy Dispersive X-ray Spectroscopy. The obtained nanoparticles showed a small dispersion, with a size range of 3.2-3.5 nm. Their crystal structure is in good agreement with the bulk martensitic structure of the targets. In this sense, results on morphology, composition and crystal structure have indicated that it is possible to produce nanoparticles of CuZnAl shape memory alloys with martensitic structure in a single process using Ion Milling. (author)

  14. ZK60 alloy processed by ECAP: Microstructural, physical and mechanical characterization

    Energy Technology Data Exchange (ETDEWEB)

    Dumitru, F.-D., E-mail: dianadumitru1986@yahoo.com [Materials Science and Engineering Faculty, Politehnica University of Bucharest, Splaiul Independentei 313, 060042 Bucharest (Romania); Higuera-Cobos, O.F., E-mail: osfahico@gmail.com [Departamento de Ciencia de los Materiales e Ingeniería Metalúrgica, ETSEIB – Universidad Politécnica de Cataluña, Av. Diagonal 647, 08028 Barcelona (Spain); Facultad de Ingeniería Mecánica, Universidad Tecnológica de Pereira, Vereda La Julita, Pereira (Colombia); Cabrera, J.M., E-mail: jose.maria.cabrera@upc.es [Departamento de Ciencia de los Materiales e Ingeniería Metalúrgica, ETSEIB – Universidad Politécnica de Cataluña, Av. Diagonal 647, 08028 Barcelona (Spain); Fundació CTM Centre Tecnológic, Plaça de la Ciència 2, 08243 Manresa (Spain)

    2014-01-31

    Lately, magnesium alloys have been extensively investigated through severe plastic deformation (SPD) methods in order to extend their application to structural components. In the present work, as-extruded ZK60 magnesium alloy samples were subjected to 4 passes of equal-channel angular pressing (ECAP) at a processing temperature of 250 °C, following route Bc. The microstructural evolution of the deformed grains was analyzed using electron back-scattered diffraction (EBSD). The Orientation Imaging Microscopy (OIM) maps, together with the grain boundary misorientation distribution showed a reduction in the grain size accompanied by a large proportion of high angle grain boundaries. Calorimetric analysis showed a slight increase in the recrystallization temperature of the ECAPed magnesium samples. Mechanical tests showed an improvement in the elongation-to-failure after 4 ECAP passes, which were about 2 times higher than in the as-extruded sample. Also a brittle to ductile transition was observed.

  15. New Developments of Ti-Based Alloys for Biomedical Applications

    Science.gov (United States)

    Li, Yuhua; Yang, Chao; Zhao, Haidong; Qu, Shengguan; Li, Xiaoqiang; Li, Yuanyuan

    2014-01-01

    Ti-based alloys are finding ever-increasing applications in biomaterials due to their excellent mechanical, physical and biological performance. Nowdays, low modulus β-type Ti-based alloys are still being developed. Meanwhile, porous Ti-based alloys are being developed as an alternative orthopedic implant material, as they can provide good biological fixation through bone tissue ingrowth into the porous network. This paper focuses on recent developments of biomedical Ti-based alloys. It can be divided into four main sections. The first section focuses on the fundamental requirements titanium biomaterial should fulfill and its market and application prospects. This section is followed by discussing basic phases, alloying elements and mechanical properties of low modulus β-type Ti-based alloys. Thermal treatment, grain size, texture and properties in Ti-based alloys and their limitations are dicussed in the third section. Finally, the fourth section reviews the influence of microstructural configurations on mechanical properties of porous Ti-based alloys and all known methods for fabricating porous Ti-based alloys. This section also reviews prospects and challenges of porous Ti-based alloys, emphasizing their current status, future opportunities and obstacles for expanded applications. Overall, efforts have been made to reveal the latest scenario of bulk and porous Ti-based materials for biomedical applications. PMID:28788539

  16. New Developments of Ti-Based Alloys for Biomedical Applications

    Directory of Open Access Journals (Sweden)

    Yuhua Li

    2014-03-01

    Full Text Available Ti-based alloys are finding ever-increasing applications in biomaterials due to their excellent mechanical, physical and biological performance. Nowdays, low modulus β-type Ti-based alloys are still being developed. Meanwhile, porous Ti-based alloys are being developed as an alternative orthopedic implant material, as they can provide good biological fixation through bone tissue ingrowth into the porous network. This paper focuses on recent developments of biomedical Ti-based alloys. It can be divided into four main sections. The first section focuses on the fundamental requirements titanium biomaterial should fulfill and its market and application prospects. This section is followed by discussing basic phases, alloying elements and mechanical properties of low modulus β-type Ti-based alloys. Thermal treatment, grain size, texture and properties in Ti-based alloys and their limitations are dicussed in the third section. Finally, the fourth section reviews the influence of microstructural configurations on mechanical properties of porous Ti-based alloys and all known methods for fabricating porous Ti-based alloys. This section also reviews prospects and challenges of porous Ti-based alloys, emphasizing their current status, future opportunities and obstacles for expanded applications. Overall, efforts have been made to reveal the latest scenario of bulk and porous Ti-based materials for biomedical applications.

  17. TOPICAL REVIEW: The physics of chromatin

    Science.gov (United States)

    Schiessel, Helmut

    2003-05-01

    Recent progress has been made in the understanding of the physical properties of chromatin - the dense complex of DNA and histone proteins that occupies the nuclei of plant and animal cells. Here I will focus on the two lowest levels of the hierarchy of DNA folding into the chromatin complex. (i) The nucleosome, the chromatin repeating unit consisting of a globular aggregate of eight histone proteins with the DNA wrapped around it: its overcharging, the DNA unwrapping transition, the 'sliding' of the octamer along the DNA. (ii) The 30 nm chromatin fibre, the necklace-like structure of nucleosomes connected via linker DNA: its geometry, its mechanical properties under stretching and its response to changing ionic conditions. I will stress that chromatin combines two seemingly contradictory features: (1) high compaction of DNA within the nuclear envelope and, at the same time, (2) accessibility to genes, promoter regions and gene regulatory sequences.

  18. On the Physics of Machining Titanium Alloys: Interactions between Cutting Parameters, Microstructure and Tool Wear

    Directory of Open Access Journals (Sweden)

    Mohammed Nouari

    2014-07-01

    Full Text Available The current work deals with the analysis of mechanisms involved during the machining process of titanium alloys. Two different materials were chosen for the study: Ti-6Al-4V and Ti-55531. The objective was to understand the effect of all cutting parameters on the tool wear behavior and stability of the cutting process. The investigations were focused on the mechanisms of the chip formation process and their interaction with tool wear. At the microstructure scale, the analysis confirms the intense deformation of the machined surface and shows a texture modification. As the cutting speed increases, cutting forces and temperature show different progressions depending on the considered microstructure (Ti-6Al-4V or Ti-55531 alloy. Results show for both materials that the wear process is facilitated by the high cutting temperature and the generation of high stresses. The analysis at the chip-tool interface of friction and contact nature (sliding or sticking contact shows that machining Ti55531 often exhibits an abrasion wear process on the tool surface, while the adhesion and diffusion modes followed by the coating delamination process are the main wear modes when machining the usual Ti-6Al-4V alloy.

  19. A Critical Review of High Entropy Alloys and Related Concepts (Postprint)

    Science.gov (United States)

    2016-10-21

    orthopedic surgery and dental appliances. As many as 18 elements are known to produce SMAs, giving opportunities for concentrated alloying. Other...performed here, results from each report are counted with equal weight. This is an imperfect approach, since alloys, micro - structures and phases that...and 4.2.2 thus report the percentages of total microstructure reports that display particular phases or micro - structures in the alloys selected for

  20. Obesity and physical activity: a review.

    Science.gov (United States)

    Bensimhon, Daniel R; Kraus, William E; Donahue, Mark P

    2006-03-01

    Obesity has become a problem of epidemic proportions in the U.S., with nearly two thirds of American adults being either overweight or obese. Current data suggest that this trend remains on the rise and threatens many of the gains that have been made in the prevention and treatment of heart disease. Exercise has long been considered an integral component of weight management, but available evidence suggests that exercise alone is a relatively inefficient means for losing weight. In contrast, regular exercise appears crucial in the prevention of weight gain and successful maintenance of weight loss, and in the fostering of cardiovascular health. This article reviews the available literature regarding the role of exercise in the prevention and treatment of obesity and evaluates the adequacy of current national guidelines.

  1. Physical activity associate low back pain and intervention program: Review

    Science.gov (United States)

    Ibrahim, Muhamad Aizat Mat; Hasbollah, Hasif Rafidee; Ibrahim, Mohd Asrul Hery; Marican, Nor Dalila; Halim, Muhd Hafzal Abdul; Rashid, Ahmad Faezi Ab.; Yasin, Nurul Hafizah Mohd

    2017-10-01

    The person who have low back pain often report impaired disability to performance daily activities which passive movement of daily life. The effects of low back pain on daily function of patients can describe as a patients level of disability or reduction in physical function it interferes with the movement of patients for running a daily lives. Therefore, the aim of this study was to conduct a review to examine the relationship between physical activity and low back pain. Besides that, the suggestion prevention program to patient who has low back pain. This systematic review study was used internet to find databases and search engines. Data were collected using Wiley online library, Bioline International, SAGE, Science Direct, NCBI, ProQuest, Biomed central, American Diabetes Association, PLOS One and Springer. The search was performed using keywords of "physical activity", "low back pain", "back pain", "activity level" and "intervention". The study was reviewed the resources and the results were classified in different section The results were classified based on several sections including years of reporting, who were reporting, the origins of articles and their health criteria about physical activity and low back pain. There are positive associate physical activity and low back pain from the systematic review. Future intervention treatment can reduce associate physical activity to low back pain.

  2. BOOK REVIEW: Physics in the Real World

    Science.gov (United States)

    Jardine, Jim

    2000-05-01

    after stirring? I have a sense of déjà vu with this last question as it and others in this book were also discussed in the brilliantly written and illustrated volume Riddles in your Teacup, published by the Institute of Physics a few years ago. Miscellaneous. This section deals with topics such as quartz halogen lamps, degreening oranges, free-fall phenomena and a discussion on the origins of the terms `physics' and `physicist'. The concluding section is devoted exclusively to Rudolph the Red-nosed Reindeer and Santa Claus. It is clearly intended to convince readers that Physics is (still) Fun!

  3. Definitions, Foundations and Associations of Physical Literacy: A Systematic Review.

    Science.gov (United States)

    Edwards, Lowri C; Bryant, Anna S; Keegan, Richard J; Morgan, Kevin; Jones, Anwen M

    2017-01-01

    The concept of physical literacy has stimulated increased research attention in recent years-being deployed in physical education, sport participation, and the promotion of physical activity. Independent research groups currently operationalize the construct differently. The purpose of this systematic review was to conduct a systematic review of the physical literacy construct, as reflected in contemporary research literature. Five databases were searched using the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines for systematic reviews. Inclusion criteria were English language, peer reviewed, published by March 2016, and seeking to conceptualize physical literacy. Articles that met these criteria were analyzed in relation to three core areas: properties/attributes, philosophical foundations and theoretical associations with other constructs. A total of 50 published articles met the inclusion criteria and were analyzed qualitatively using inductive thematic analysis. The thematic analysis addressed the three core areas. Under definitions, core attributes that define physical literacy were identified, as well as areas of conflict between different approaches currently being adopted. One relatively clear philosophical approach was prominent in approximately half of the papers, based on a monist/holistic ontology and phenomenological epistemology. Finally, the analysis identified a number of theoretical associations, including health, physical activity and academic performance. Current literature contains different representations of the physical literacy construct. The costs and benefits of adopting an exclusive approach versus pluralism are considered. Recommendations for both researchers and practitioners focus on identifying and clearly articulating the definitions, philosophical assumptions and expected outcomes prior to evaluating the effectiveness of this emerging concept.

  4. Physical activity and physical self-concept in youth: systematic review and meta-analysis.

    Science.gov (United States)

    Babic, Mark J; Morgan, Philip J; Plotnikoff, Ronald C; Lonsdale, Chris; White, Rhiannon L; Lubans, David R

    2014-11-01

    Evidence suggests that physical self-concept is associated with physical activity in children and adolescents, but no systematic review of this literature has been conducted. The primary aim of this systematic review and meta-analysis was to determine the strength of associations between physical activity and physical self-concept (general and sub-domains) in children and adolescents. The secondary aim was to examine potential moderators of the association between physical activity and physical self-concept. A systematic search of six electronic databases (MEDLINE, CINAHL, SPORTDiscus, ERIC, Web of Science and Scopus) with no date restrictions was conducted. Random effects meta-analyses with correction for measurement were employed. The associations between physical activity and general physical self-concept and sub-domains were explored. A risk of bias assessment was conducted by two reviewers. The search identified 64 studies to be included in the meta-analysis. Thirty-three studies addressed multiple outcomes of general physical self-concept: 28 studies examined general physical self-concept, 59 examined perceived competence, 25 examined perceived fitness, and 55 examined perceived appearance. Perceived competence was most strongly associated with physical activity (r = 0.30, 95% CI 0.24-0.35, p self-concept (r = 0.25, 95% CI 0.16-0.34, p self-concept (p self-concept and its various sub-domains in children and adolescents. Age and sex are key moderators of the association between physical activity and physical self-concept.

  5. Quality in physical therapist clinical education: a systematic review.

    Science.gov (United States)

    McCallum, Christine A; Mosher, Peter D; Jacobson, Peri J; Gallivan, Sean P; Giuffre, Suzanne M

    2013-10-01

    Many factors affect student learning throughout the clinical education (CE) component of professional (entry-level) physical therapist education curricula. Physical therapist education programs (PTEPs) manage CE, yet the material and human resources required to provide CE are generally overseen by community-based physical therapist practices. The purposes of this systematic review were: (1) to examine how the construct of quality is defined in CE literature and (2) to determine the methodological rigor of the available evidence on quality in physical therapist CE. This study was a systematic review of English-language journals using the American Physical Therapy Association's Open Door Portal to Evidence-Based Practice as the computer search engine. The search was categorized using terms for physical therapy and quality and for CE pedagogy and models or roles. Summary findings were characterized by 5 primary themes and 14 subthemes using a qualitative-directed content analysis. Fifty-four articles were included in the study. The primary quality themes were: CE framework, CE sites, structure of CE, assessment in CE, and CE faculty. The methodological rigor of the studies was critically appraised using a binary system based on the McMaster appraisal tools. Scores ranged from 3 to 14. Publication bias and outcome reporting bias may be inherent limitations to the results. The review found inconclusive evidence about what constitutes quality or best practice for physical therapist CE. Five key constructs of CE were identified that, when aggregated, could construe quality.

  6. Getting started--a review of physical activity adoption studies.

    Science.gov (United States)

    Dunn, A L

    1996-01-01

    The aim of this paper has been to review methods that have been found to be effective in getting sedentary adults to adopt physical activity, to examine these methods within the multilevel framework conceptualised by Winett et al, and to provide recommendations for future research to test new methods and their effectiveness in leading to the adoption of physical activity in sedentary populations. Searches for relevant studies were conducted on the Medline computerised database. Additional studies were located in reference sections of these studies and other review papers. Surveys that specifically identified determinants of adoption of physical activity in adults were included. Reviewed articles were selected on the basis of quasi-experimental and experimental designs that specifically examined the question of how to get sedentary adults to adopt a programme of physical activity or exercise, had completely described methods, and evaluated the effectiveness of methods of increasing physical activity and/or exercise. While numerous reviews have been written on determinants on physical activity adoption and maintenance, only two prospective surveys have identified specifics of adoption of physical activity. Most of the evidence for techniques that help inactive people to adopt physical activity comes from quasi-experimental and experimental intervention studies examining various cognitive and behavioural strategies at the individual level. Fewer studies have examined techniques at the interpersonal, organisational, community, environmental, and policy level. More prospective observational studies aimed at homogeneous subgroups are needed to identify correlates of physical activity adoption to help tailor interventions. Continued clinical studies are needed to differentiate the necessary and sufficient strategies at the personal and interpersonal levels. Interventions aimed at environmental, institutional, and social levels remain largely unexplored and there is a need

  7. Some applications of mathematics in theoretical physics - A review

    Energy Technology Data Exchange (ETDEWEB)

    Bora, Kalpana [Physics Department, Gauhati University, Guwahati-781014, Assam (India)

    2016-06-21

    Mathematics is a very beautiful subject−very much an indispensible tool for Physics, more so for Theoretical Physics (by which we mean here mainly Field Theory and High Energy Physics). These branches of Physics are based on Quantum Mechanics and Special Theory of Relativity, and many mathematical concepts are used in them. In this work, we shall elucidate upon only some of them, like−differential geometry, infinite series, Mellin transforms, Fourier and integral transforms, special functions, calculus, complex algebra, topology, group theory, Riemannian geometry, functional analysis, linear algebra, operator algebra, etc. We shall also present, some physics issues, where these mathematical tools are used. It is not wrong to say that Mathematics is such a powerful tool, without which, there can not be any Physics theory!! A brief review on our research work is also presented.

  8. Some applications of mathematics in theoretical physics - A review

    Science.gov (United States)

    Bora, Kalpana

    2016-06-01

    Mathematics is a very beautiful subject-very much an indispensible tool for Physics, more so for Theoretical Physics (by which we mean here mainly Field Theory and High Energy Physics). These branches of Physics are based on Quantum Mechanics and Special Theory of Relativity, and many mathematical concepts are used in them. In this work, we shall elucidate upon only some of them, like-differential geometry, infinite series, Mellin transforms, Fourier and integral transforms, special functions, calculus, complex algebra, topology, group theory, Riemannian geometry, functional analysis, linear algebra, operator algebra, etc. We shall also present, some physics issues, where these mathematical tools are used. It is not wrong to say that Mathematics is such a powerful tool, without which, there can not be any Physics theory!! A brief review on our research work is also presented.

  9. Some applications of mathematics in theoretical physics - A review

    International Nuclear Information System (INIS)

    Bora, Kalpana

    2016-01-01

    Mathematics is a very beautiful subject−very much an indispensible tool for Physics, more so for Theoretical Physics (by which we mean here mainly Field Theory and High Energy Physics). These branches of Physics are based on Quantum Mechanics and Special Theory of Relativity, and many mathematical concepts are used in them. In this work, we shall elucidate upon only some of them, like−differential geometry, infinite series, Mellin transforms, Fourier and integral transforms, special functions, calculus, complex algebra, topology, group theory, Riemannian geometry, functional analysis, linear algebra, operator algebra, etc. We shall also present, some physics issues, where these mathematical tools are used. It is not wrong to say that Mathematics is such a powerful tool, without which, there can not be any Physics theory!! A brief review on our research work is also presented.

  10. Adolescent physical activity and health: a systematic review.

    Science.gov (United States)

    Hallal, Pedro C; Victora, Cesar G; Azevedo, Mario R; Wells, Jonathan C K

    2006-01-01

    Physical activity in adolescence may contribute to the development of healthy adult lifestyles, helping reduce chronic disease incidence. However, definition of the optimal amount of physical activity in adolescence requires addressing a number of scientific challenges. This article reviews the evidence on short- and long-term health effects of adolescent physical activity. Systematic reviews of the literature were undertaken using a reference period between 2000 and 2004, based primarily on the MEDLINE/PubMed database. Relevant studies were identified by examination of titles, abstracts and full papers, according to inclusion criteria defined a priori. A conceptual framework is proposed to outline how adolescent physical activity may contribute to adult health, including the following pathways: (i) pathway A--tracking of physical activity from adolescence to adulthood; (ii) pathway B--direct influence of adolescent physical activity on adult morbidity; (iii) pathway C--role of physical activity in treating adolescent morbidity; and (iv) pathway D - short-term benefits of physical activity in adolescence on health. The literature reviews showed consistent evidence supporting pathway 'A', although the magnitude of the association appears to be moderate. Thus, there is an indirect effect on all health benefits resulting from adult physical activity. Regarding pathway 'B', adolescent physical activity seems to provide long-term benefits on bone health, breast cancer and sedentary behaviours. In terms of pathway 'C', water physical activities in adolescence are effective in the treatment of asthma, and exercise is recommended in the treatment of cystic fibrosis. Self-esteem is also positively affected by adolescent physical activity. Regarding pathway 'D', adolescent physical activity provides short-term benefits; the strongest evidence refers to bone and mental health. Appreciation of different mechanisms through which adolescent physical activity may influence adult

  11. BOOK REVIEW: Astrophysics (Advanced Physics Readers)

    Science.gov (United States)

    Kibble, Bob

    2000-07-01

    Here is a handy and attractive reader to support students on post-16 courses. It covers the astrophysics, astronomy and cosmology that are demanded at A-level and offers anyone interested in these fields an interesting and engaging reference book. The author and the production team deserve credit for producing such an attractive book. The content, in ten chapters, covers what one would expect at this level but it is how it is presented that struck me as the book's most powerful asset. Each chapter ends with a summary of key ideas. Line drawings are clear and convey enough information to make them more than illustrations - they are as valuable as the text in conveying information. Full colour is used throughout to enhance illustrations and tables and to lift key sections of the text. A number of colour photographs complement the material and serve to maintain interest and remind readers that astrophysics is about real observable phenomena. Included towards the end is a set of tables offering information on physical and astronomical data, mathematical techniques and constellation names and abbreviations. This last table puzzled me as to its value. There is a helpful bibliography which includes society contacts and a website related to the text. Perhaps my one regret is that there is no section where students are encouraged to actually do some real astronomy. Astrophysics is in danger of becoming an armchair and calculator interest. There are practical projects that students could undertake either for school assessment or for personal interest. Simple astrophotography to capture star trails, observe star colours and estimate apparent magnitudes is an example, as is a simple double-star search. There are dozens more. However, the author's style is friendly and collaborative. He befriends the reader as they journey together through the ideas. There are progress questions at the end of each chapter. Their style tends to be rather closed and they emphasize factual recall

  12. Physical Activity as a Vital Sign: A Systematic Review

    OpenAIRE

    Golightly, Yvonne M.; Allen, Kelli D.; Ambrose, Kirsten R.; Stiller, Jamie L.; Evenson, Kelly R.; Voisin, Christiane; Hootman, Jennifer M.; Callahan, Leigh F.

    2017-01-01

    Introduction Physical activity (PA) is strongly endorsed for managing chronic conditions, and a vital sign tool (indicator of general physical condition) could alert providers of inadequate PA to prompt counseling or referral. This systematic review examined the use, definitions, psychometric properties, and outcomes of brief PA instruments as vital sign measures, with attention primarily to studies focused on arthritis. Methods Electronic databases were searched for English-language literatu...

  13. [Are Interventions Promoting Physical Activity Cost-Effective? A Systematic Review of Reviews].

    Science.gov (United States)

    Rütten, Alfred; Abu-Omar, Karim; Burlacu, Ionut; Schätzlein, Valentin; Suhrcke, Marc

    2017-03-01

    On the basis of international published reviews, this systematic review aims to determine the health economic benefits of interventions promoting physical activity.This review of reviews is based on a systematic literature research in 10 databases (e. g. PubMed, Scopus, SPORTDiscus) supplemented by hand searches from January 2000 to October 2015. Publications were considered in the English or German language only. Results of identified reviews were derived.In total, 18 reviews were identified that could be attributed to interventions promoting physical activity (2 reviews focusing on population-based physical activity interventions, 10 reviews on individual-based and 6 reviews on both population-based and individual-based physical activity interventions). Results showed that population-based physical activity interventions are of great health economic potential if reaching a wider population at comparably low costs. Outstanding are political and environmental strategies, as well as interventions supporting behavioural change through information. The most comprehensive documentation for interventions promoting physical activity could be found for individual-based strategies (i. e. exercise advice or exercise programs). However, such programs are comparatively less cost-effective due to limited reach and higher utilization of resources.The present study provides an extensive review and analysis of the current international state of research regarding the health economic evaluation of interventions promoting physical activity. Results show favourable cost-effectiveness for interventions promoting physical activity, though significant differences in the effectiveness between various interventions were noticed. The greatest potential for cost-effectiveness can be seen in population-based interventions. At the same time, there is a need to acknowledge the limitations of the economic evidence in this field which are attributable to methodological challenges and

  14. Modeling of Some Physical Properties of Zirconium Alloys for Nuclear Applications in Support of UFD Campaign

    Energy Technology Data Exchange (ETDEWEB)

    Michael V. Glazoff

    2013-08-01

    Zirconium-based alloys Zircaloy-2 and Zircaloy-4 are widely used in the nuclear industry as cladding materials for light water reactor (LWR) fuels. These materials display a very good combination of properties such as low neutron absorption, creep behavior, stress-corrosion cracking resistance, reduced hydrogen uptake, corrosion and/or oxidation, especially in the case of Zircaloy-4. However, over the last couple of years, in the post-Fukushima Daiichi world, energetic efforts have been undertaken to improve fuel clad oxidation resistance during off-normal temperature excursions. Efforts have also been made to improve upon the already achieved levels of mechanical behavior and reduce hydrogen uptake. In order to facilitate the development of such novel materials, it is very important to achieve not only engineering control, but also a scientific understanding of the underlying material degradation mechanisms, both in working conditions and in storage of used nuclear fuel. This report strives to contribute to these efforts by constructing the thermodynamic models of both alloys; constructing of the respective phase diagrams, and oxidation mechanisms. A special emphasis was placed upon the role of zirconium suboxides in hydrogen uptake reduction and the atomic mechanisms of oxidation. To that end, computational thermodynamics calculations were conducted concurrently with first-principles atomistic modeling.

  15. Neuroergonomics: A Review of Applications to Physical and Cognitive Work

    Directory of Open Access Journals (Sweden)

    Ranjana K Mehta

    2013-12-01

    Full Text Available Neuroergonomics is an emerging science that is defined as the study of the human brain in relation to performance at work and in everyday settings. This paper provides a critical review of the neuroergonomic approach to evaluating physical and cognitive work, particularly in mobile settings. Neuroergonomics research employing mobile and immobile brain imaging techniques are discussed in the following areas of physical and cognitive work: 1 physical work parameters; 2 physical fatigue; 3 vigilance and mental fatigue; 4 training and neuroadaptive systems; and 5 assessment of concurrent physical and cognitive work. Finally, the integration of brain and body measurements in investigating workload and fatigue, in the context of mobile brain/body imaging ('MoBI', is discussed.

  16. Radiation therapy dosimetry reviews by the centers for radiological physics

    International Nuclear Information System (INIS)

    Samulski, T.; Dubuque, G.L.; Cacak, R.K.

    1981-01-01

    Six Centers for Radiological Physics (CRP) have performed over 250 dosimetric site reviews at institutions participating in the Division of Cancer Control and Rehabilitation therapy networks and/or as affiliates in Oncology Group Clinical trials. For the initial site visits, institution stated output calibration was within +- 3% of that measured by the CRPs for 87% of the therapy machines reviewed. The accuracy of methods utilized in calculating tumor dose were assessed by using a set of reference cases of varying complexity. Many institutions have received multiple reviews and a significant reduction in the variance of machine calibration and calculated tumor dose for the reference cases is evident

  17. Laser surface alloying of aluminium-transition metal alloys

    International Nuclear Information System (INIS)

    Almeida, A.; Vilar, R.

    1998-01-01

    Laser surface alloying has been used as a tool to produce hard and corrosion resistant Al-transition metal (TM) alloys. Cr and Mo are particularly interesting alloying elements to produce stable high-strength alloys because they present low diffusion coefficients and solid solubility in Al. To produce Al-TM surface alloys a two-step laser process was developed: firstly, the material is alloyed using low scanning speed and secondly, the microstructure is modified by a refinement step. This process was used in the production of Al-Cr, Al-Mo and Al-Mo and Al-Nb surface alloys by alloying Cr, Mo or Nb powder into an Al and 7175 Al alloy substrate using a CO 2 laser . This paper presents a review of the work that has been developed at Instituto Superior Tecnico on laser alloying of Al-TM alloy, over the last years. (Author) 16 refs

  18. 78 FR 16301 - Proposal Review Panel for Physics; Notice of Meeting

    Science.gov (United States)

    2013-03-14

    ... NATIONAL SCIENCE FOUNDATION Proposal Review Panel for Physics; Notice of Meeting In accordance... announces the following meeting. Name: LIGO Annual Review Site Visit at Hanford Observatory for Physics... Physics, National Science Foundation, Arlington, VA (703) 292-4432. [[Page 16302

  19. A study of environmental characterization of conventional and advanced aluminum alloys for selection and design. Phase 1: Literature review

    Science.gov (United States)

    Sprowls, D. O.

    1984-01-01

    A review of the literature is presented with the objectives of identifying relationships between various accelerated stress corrosion testing techniques, and for determining the combination of test methods best suited to selection and design of high strength aluminum alloys. The following areas are reviewed: status of stress-corrosion test standards, the influence of mechanical and environmental factors on stress corrosion testing, correlation of accelerated test data with in-service experience, and procedures used to avoid stress corrosion problems in service. Promising areas for further work are identified.

  20. 76 FR 8381 - Proposal Review for Physics; Notice of Meeting

    Science.gov (United States)

    2011-02-14

    ... NATIONAL SCIENCE FOUNDATION Proposal Review for Physics; Notice of Meeting In accordance with the... advice and recommendations concerning progress of the Center for Magnetic Self-Organization in Laboratory.... 552b(c), of the Government in the Sunshine Act. Dated: February 9, 2011. Suzanne H. Plimpton, Reports...

  1. Physical Activity and Social Support in Adolescents: A Systematic Review

    Science.gov (United States)

    Mendonça, Gerfeson; Cheng, Luanna Alexandra; Mélo, Edilânea Nunes; de Farias, José Cazuza, Jr.

    2014-01-01

    The objective of this review was to systematically synthesize the results of original studies on the association between physical activity and social support in adolescents, published until April 2011. Searches were carried out in Adolec, ERIC, Lilacs, Medline, SciELO, Scopus, SportsDiscus and Web of Science electronic databases and the reference…

  2. 78 FR 25309 - Proposal Review Panel Physics; Notice of Meeting

    Science.gov (United States)

    2013-04-30

    ...: 703-292-8783. Purpose of Meeting: To review the progress of the Center for the Physics of Living Cells...--Welcome and Presentation of PFC. 10:00 a.m.-12:00 noon Closed--Science and Future plans reports. 12:00....m.-5:00 p.m. Closed--Executive Sessions: Science and Future Plans Presentations, Outreach and...

  3. A Review of Swimming Cues and Tips for Physical Education

    Science.gov (United States)

    Higginson, Kelsey; Barney, David

    2016-01-01

    Swimming is a low-impact activity that causes little stress on joints so it can be done for a lifetime. Many teachers may wish to teach swimming but do not have cues or ideas for doing so. This article reviews swimming cues, relays and equipment that can help a physical education teacher include a swimming unit in their curriculum. Certification…

  4. Discussion of gender in Physical Education classes: a systematic review

    Directory of Open Access Journals (Sweden)

    Naiara da Rocha Matos

    2016-05-01

    Full Text Available The aim of this study was to verify through systematic review the implications of the possible participation or / non-participation of girls in physical education classes. It is a systematic literature review conducted in CAPES Journal Portal databases and Lilacs, and in scientific journals Motrivivência and Physical Education Magazine. Initially it found a total of 260 articles, analyzed which have been titles, abstracts, and later the full article, only 07 being selected articles. Therefore,  us articles selected there is a strong built influence historically and rooted in society about girls' participation in physical education classes, these are considered less skilled for sports compared to boys, society, as well as school end up further enhance this male superiority.

  5. Review of lattice results concerning low-energy particle physics

    International Nuclear Information System (INIS)

    Aoki, S.; Aoki, Y.; Brookhaven National Laboratory, Upton, NY; Becirevic, D.

    2016-07-01

    We review lattice results related to pion, kaon, D- and B-meson physics with the aim of making them easily accessible to the particle physics community. More specifically, we report on the determination of the light-quark masses, the form factor f + (0), arising in the semileptonic K→π transition at zero momentum transfer, as well as the decay constant ratio f K /f π and its consequences for the CKM matrix elements V us and V ud . Furthermore, we describe the results obtained on the lattice for some of the low-energy constants of SU(2) L x SU(2) R and SU(3) L x SU(3) R Chiral Perturbation Theory. We review the determination of the B K parameter of neutral kaon mixing as well as the additional four B parameters that arise in theories of physics beyond the Standard Model. The latter quantities are an addition compared to the previous review. For the heavy-quark sector, we provide results for m c and m b (also new compared to the previous review), as well as those for D- and B-meson decay constants, form factors, and mixing parameters. These are the heavy-quark quantities most relevant for the determination of CKM matrix elements and the global CKM unitarity-triangle fit. Finally, we review the status of lattice determinations of the strong coupling constant α s .

  6. A review of physical and mental health in homeless persons.

    Science.gov (United States)

    Martens, W H

    2001-01-01

    To review the physical and mental status in homeless people. A MEDLINE database search covering 5 decades was supplemented by tracing back through references from existing review work. Over 200 articles were extracted, and 106 were selected for review. Homeless persons suffer frequently from physical health problems like tuberculosis, asthma, bronchitis, HIV infection, and as a consequence, they run an increased risk for premature mortality. The prevalence of mental disorders among homeless individuals varies from 80-95% in the USA, Australia, Canada, Norway, and Germany to 25-33% in Ireland and Spain. The most prominent mental disorders among the homeless, which vary from country to country, are depression, affective disorders, substance abuse, psychotic disorders, schizophrenia, and personality disorders. Homelessness is a major public health problem that should have our special interest.

  7. A Review of Physical Activity Interventions Delivered via Facebook.

    Science.gov (United States)

    Ferrer, David A; Ellis, Rebecca

    2017-10-01

    The use of social networking sites to deliver behavioral interventions is becoming more prevalent. The purpose of this review was to systematically evaluate the published research to determine the effectiveness of Facebook-delivered interventions for promoting physical activity behavior change. A search of interventions delivered via Facebook (as the primary delivery method or part of a multifaceted intervention) in which physical activity was the primary or secondary outcome resulted in 8 studies for review. Overall, 87.5% of the Facebook interventions reported some type of significant physical activity behavior change (ie, interactions, main effects for time, differences between conditions); however, only 2 of these interventions found this change to be significantly better for the treatment group than the control group. Future researchers are encouraged to test the effectiveness of Facebook-delivered physical activity interventions with additional control groups that receive no aspects of the intervention within experimental study designs, more diverse samples, theory-based content with assessment of mediators of behavior change, direct observations of physical activity, and long-term follow-ups. Although based on a small sample of studies, Facebook appears to be a promising delivery method for physical activity interventions.

  8. Systematic review of the association between physical activity and burnout.

    Science.gov (United States)

    Naczenski, Lea M; Vries, Juriena D de; Hooff, Madelon L M van; Kompier, Michiel A J

    2017-11-25

    Burnout constitutes a health risk, and interventions are needed to reduce it. The aim of this study was to synthesize evidence regarding the relationship between physical activity and burnout by conducting a systematic review of longitudinal and intervention studies. A literature search resulted in the identification of a final set of ten studies: four longitudinal and six intervention studies. In separate analyses for each category, evidence was synthesized by extracting the study characteristics and assessing the methodological quality of each study. The strength of evidence was calculated with the standardized index of convergence (SIC). In longitudinal studies, we found moderately strong evidence (SIC (4) = -1) for a negative relationship between physical activity and the key component of burnout, i.e., exhaustion. We found strong evidence (SIC (6) = -0.86) for the effect of physical activity on reducing exhaustion in intervention studies. As only one study could be classified as a high quality study, these results of previous studies need to be interpreted with some caution. This systematic review suggests that physical activity constitutes an effective medium for the reduction of burnout. Although consistent evidence was found, there is a lack of high quality longitudinal and intervention studies considering the influence of physical activity on burnout. Therefore, future research should be conducted with the aim to produce high quality studies, to develop a full picture of physical activity as a strategy to reduce burnout.

  9. Effect of hydrogen on Fe and Pd alloying and physical properties

    Czech Academy of Sciences Publication Activity Database

    Jirásková, Yvonna; Buršík, Jiří; Zemanová, Adéla; Čízek, J.; Hruška, P.; Životský, O.

    2017-01-01

    Roč. 42, č. 10 (2017), s. 6885-6901 ISSN 0360-3199 R&D Projects: GA MŠk(CZ) LQ1601 Institutional support: RVO:68081723 Keywords : positron-lifetime spectroscopy * neutron-diffraction * magnetic-properties * palladium-hydrogen * induced defects * iron Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.) Impact factor: 3.582, year: 2016

  10. [Physical therapy in pediatric primary care: a review of experiences].

    Science.gov (United States)

    de Sá, Miriam Ribeiro Calheiros; Thomazinho, Paula de Almeida; Santos, Fabiano Luiz; Cavalcanti, Nicolette Celani; Ribeiro, Carla Trevisan Martins; Negreiros, Maria Fernanda Vieira; Vinhaes, Marcia Regina

    2014-11-01

    To review pediatric physical therapy experiences described in the literature and to analyze the production of knowledge on physical therapy in the context of pediatric primary health care (PPHC). A systematic review was conducted according to the PRISMA criteria. The following databases were searched: MEDLINE, LILACS, SciELO, PubMed, Scopus and Cochrane; Brazilian Ministry of Health's CAPES doctoral dissertations database; and System for Information on Grey Literature in Europe (SIGLE). The following search terms were used: ["primary health care" and ("physical therapy" or "physiotherapy") and ("child" or "infant")] and equivalent terms in Portuguese and Spanish, with no restriction on publication year. Thirteen articles from six countries were analyzed and grouped into three main themes: professional dilemmas (three articles), specific competencies and skills required in a PPHC setting (seven articles), and practice reports (four articles). Professional dilemmas involved expanding the role of physical therapists to encompass community environments and sharing the decision-making process with the family, as well as collaborative work with other health services to identify the needs of children. The competencies and skills mentioned in the literature related to the identification of clinical and sociocultural symptoms that go beyond musculoskeletal conditions, the establishment of early physical therapy diagnoses, prevention of overmedication, and the ability to work as team players. Practice reports addressed stimulation in children with neurological diseases, respiratory treatment, and establishing groups with mothers of children with these conditions. The small number of studies identified in this review suggests that there is little knowledge regarding the roles of physical therapists in PPHC and possibly regarding the professional abilities required in this setting. Therefore, further studies are required to provide data on the field, along with a continuing

  11. Solid state dosimeters used in medical physics "A review"

    Science.gov (United States)

    Azorín-Nieto, Juan

    2012-10-01

    Many solid-state detectors have been successfully used to perform the quality control and in vivo dosimetry in medical physics, both in diagnostic radiology and radiotherapy, as they have high sensitivity in a small volume; most of them do not require electrical connection and have dosimetric characteristics of interest such as: good accuracy and reproducibility, as well as a response independent of the energy of radiation, some of them. For this reason, the selection of an appropriate detector for use in medical physics must take into account the energy mass absorption coefficient relative to water for photon sources and the mass stopping power relative to water for beta emitters and electron beams in the energy range of interest in medical physics, as well as the effective atomic number of materials that constitute them. This paper presents a review of the dosimetric characteristics of the solid state dosimeters most suitable for use in medical physics.

  12. Nuclear and particle physics, astrophysics and cosmology (NPAC) capability review

    Energy Technology Data Exchange (ETDEWEB)

    Redondo, Antonio [Los Alamos National Laboratory

    2010-01-01

    The present document represents a summary self-assessment of the status of the Nuclear and Particle Physics, Astrophysics and Cosmology (NPAC) capability across Los Alamos National Laboratory (LANL). For the purpose of this review, we have divided the capability into four theme areas: Nuclear Physics, Particle Physics, Astrophysics and Cosmology, and Applied Physics. For each theme area we have given a general but brief description of the activities under the area, a list of the Laboratory divisions involved in the work, connections to the goals and mission of the Laboratory, a brief description of progress over the last three years, our opinion of the overall status of the theme area, and challenges and issues.

  13. PHYSICAL ACTIVITY AND EATING HABITS IN UNIVERSITY PROFESSORS: LITERATURE REVIEW

    Directory of Open Access Journals (Sweden)

    Hector Luiz Rodrigues Munaro

    2015-03-01

    Full Text Available Increasingly, university professors engage in academic tasks often stressful and sedentary behaviors, making the practice of physical activity and healthier eating habits. The aim of this study was to review the literature Brazilian studies on physical activity and eating habits of university professors .The search was conducted between March and May 2013, in electronic databases. For the delimitation of the study, was used as descriptors: Physical Activity, University Teachers and Eating Habits. At the end of the article selection process, remaining 06 studies that have been described and discussed in the text. And all of a descriptive nature, with small samples with some robust and consistent methodology. The selected studies, regardless of their qualities, point to the need of this population to engage in more physical activity and healthy eating habits programs.

  14. PHYSICAL ACTIVITY AND EATING HABITS IN UNIVERSITY PROFESSORS: LITERATURE REVIEW

    Directory of Open Access Journals (Sweden)

    Hector Luiz Rodrigues Munaro

    2015-01-01

    Full Text Available Increasingly, university professors engage in academic tasks often stressful and sedentary behaviors, making the practice of physical activity and healthier eating habits. The aim of this study was to review the literature Brazilian studies on physical activity and eating habits of university professors .The search was conducted between March and May 2013, in electronic databases. For the delimitation of the study, was used as descriptors: Physical Activity, University Teachers and Eating Habits. At the end of the article selection process, remaining 06 studies that have been described and discussed in the text. And all of a descriptive nature, with small samples with some robust and consistent methodology. The selected studies, regardless of their qualities, point to the need of this population to engage in more physical activity and healthy eating habits programs

  15. Appreciation of the 2015 JGR Space Physics Peer Reviewers

    Science.gov (United States)

    Liemohn, Michael W.; Balikhin, Michael; Kepko, Larry; Rodger, Alan; Wang, Yuming

    2016-01-01

    The Editors of the Journal of Geophysical Research Space Physics are deeply indebted to the many people among the research community that serve this journal through peer review. The journal could not exist without the time and effort invested by the community through this voluntary activity, providing expert evaluations and thoughtful assessments of the work of others. In 2015, the journal had 1506 scientists contribute to the process with at least one peer review, for a total of 3575 reviews completed, including additional reviews of resubmitted manuscripts. There were 277 reviewers that contributed four or more reports in 2015. The average number of reviews per referee in 2015 was, therefore, 2.4. Note that the total number of manuscript final decisions (i.e., accept or reject) for Journal of Geophysical Research (JGR) Space Physics was 1147 in 2015. Of this, 774 were accepted and 373 were declined, for an acceptance rate of 67% last year. If the 1334 "revision" decisions are included in the tally, then the total number of decisions made in 2015 was 2481. Working out the arithmetic, it means that on average, a manuscript gets about 1.2 revision decisions before a final accept-or-reject decision. This explains the 3.1 average number of reviews per manuscript throughout each paper's lifetime in the submission-revision editorial process. We are pleased and happy that the research community is willing and able to devote their resources toward this service endeavor. We appreciate each and every one of you that helped maintain the high quality of papers in JGR Space Physics last year. We look forward to another excellent year working with all of you through the year ahead.

  16. Correlates of Physical Activity of Children and Adolescents: A Systematic Review of Reviews

    Science.gov (United States)

    Sterdt, Elena; Liersch, Sebastian; Walter, Ulla

    2014-01-01

    Objective: The aim of this study was to identify promoting and inhibiting correlates associated with the physical activity (PA) of children and adolescents (aged 3-18). The intention was to demonstrate the complexity of correlates of PA and to determine possible influencing factors. Design: A systematic review of reviews. Methods: Systematic…

  17. Castability of Magnesium Alloys

    Science.gov (United States)

    Bowles, A. L.; Han, Q.; Horton, J. A.

    There is intense research effort into the development of high pressure die cast-able creep resistant magnesium alloys. One of the difficulties encountered in magnesium alloy development for creep resistance is that many additions made to improve the creep properties have reportedly resulted in alloys that are difficult to cast. It is therefore important to have an understanding of the effect of alloying elements on the castability. This paper gives a review of the state of the knowledge of the castability of magnesium alloys.

  18. Systematic review of core muscle activity during physical fitness exercises.

    Science.gov (United States)

    Martuscello, Jason M; Nuzzo, James L; Ashley, Candi D; Campbell, Bill I; Orriola, John J; Mayer, John M

    2013-06-01

    A consensus has not been reached among strength and conditioning specialists regarding what physical fitness exercises are most effective to stimulate activity of the core muscles. Thus, the purpose of this article was to systematically review the literature on the electromyographic (EMG) activity of 3 core muscles (lumbar multifidus, transverse abdominis, quadratus lumborum) during physical fitness exercises in healthy adults. CINAHL, Cochrane Central Register of Controlled Trials, EMBASE, PubMed, SPORTdiscus, and Web of Science databases were searched for relevant articles using a search strategy designed by the investigators. Seventeen studies enrolling 252 participants met the review's inclusion/exclusion criteria. Physical fitness exercises were partitioned into 5 major types: traditional core, core stability, ball/device, free weight, and noncore free weight. Strength of evidence was assessed and summarized for comparisons among exercise types. The major findings of this review with moderate levels of evidence indicate that lumbar multifidus EMG activity is greater during free weight exercises compared with ball/device exercises and is similar during core stability and ball/device exercises. Transverse abdominis EMG activity is similar during core stability and ball/device exercises. No studies were uncovered for quadratus lumborum EMG activity during physical fitness exercises. The available evidence suggests that strength and conditioning specialists should focus on implementing multijoint free weight exercises, rather than core-specific exercises, to adequately train the core muscles in their athletes and clients.

  19. Remote Physical Activity Monitoring in Neurological Disease: A Systematic Review

    Science.gov (United States)

    Block, Valerie A. J.; Pitsch, Erica; Tahir, Peggy; Cree, Bruce A. C.; Allen, Diane D.; Gelfand, Jeffrey M.

    2016-01-01

    Objective To perform a systematic review of studies using remote physical activity monitoring in neurological diseases, highlighting advances and determining gaps. Methods Studies were systematically identified in PubMed/MEDLINE, CINAHL and SCOPUS from January 2004 to December 2014 that monitored physical activity for ≥24 hours in adults with neurological diseases. Studies that measured only involuntary motor activity (tremor, seizures), energy expenditure or sleep were excluded. Feasibility, findings, and protocols were examined. Results 137 studies met inclusion criteria in multiple sclerosis (MS) (61 studies); stroke (41); Parkinson's Disease (PD) (20); dementia (11); traumatic brain injury (2) and ataxia (1). Physical activity levels measured by remote monitoring are consistently low in people with MS, stroke and dementia, and patterns of physical activity are altered in PD. In MS, decreased ambulatory activity assessed via remote monitoring is associated with greater disability and lower quality of life. In stroke, remote measures of upper limb function and ambulation are associated with functional recovery following rehabilitation and goal-directed interventions. In PD, remote monitoring may help to predict falls. In dementia, remote physical activity measures correlate with disease severity and can detect wandering. Conclusions These studies show that remote physical activity monitoring is feasible in neurological diseases, including in people with moderate to severe neurological disability. Remote monitoring can be a psychometrically sound and responsive way to assess physical activity in neurological disease. Further research is needed to ensure these tools provide meaningful information in the context of specific neurological disorders and patterns of neurological disability. PMID:27124611

  20. Yoga and physical exercise - a review and comparison.

    Science.gov (United States)

    Govindaraj, Ramajayam; Karmani, Sneha; Varambally, Shivarama; Gangadhar, B N

    2016-06-01

    Yoga is a multifaceted spiritual tool with enhanced health and well-being as one of its positive effects. The components of yoga which are very commonly applied for health benefits are asanas (physical postures), pranayama (regulated breathing) and meditation. In the context of asanas, yoga resembles more of a physical exercise, which may lead to the perception that yoga is another kind of physical exercise. This article aims at exploring the commonalities and differences between yoga and physical exercise in terms of concepts, possible mechanisms and effectiveness for health benefits. A narrative review is undertaken based on traditional and contemporary literature for yoga, along with scientific articles available on yoga and exercise including head-to-head comparative trials with healthy volunteers and patients with various disease conditions. Physical exercises and the physical components of yoga practices have several similarities, but also important differences. Evidence suggests that yoga interventions appear to be equal and/or superior to exercise in most outcome measures. Emphasis on breath regulation, mindfulness during practice, and importance given to maintenance of postures are some of the elements which differentiate yoga practices from physical exercises.

  1. Remote Physical Activity Monitoring in Neurological Disease: A Systematic Review.

    Science.gov (United States)

    Block, Valerie A J; Pitsch, Erica; Tahir, Peggy; Cree, Bruce A C; Allen, Diane D; Gelfand, Jeffrey M

    2016-01-01

    To perform a systematic review of studies using remote physical activity monitoring in neurological diseases, highlighting advances and determining gaps. Studies were systematically identified in PubMed/MEDLINE, CINAHL and SCOPUS from January 2004 to December 2014 that monitored physical activity for ≥24 hours in adults with neurological diseases. Studies that measured only involuntary motor activity (tremor, seizures), energy expenditure or sleep were excluded. Feasibility, findings, and protocols were examined. 137 studies met inclusion criteria in multiple sclerosis (MS) (61 studies); stroke (41); Parkinson's Disease (PD) (20); dementia (11); traumatic brain injury (2) and ataxia (1). Physical activity levels measured by remote monitoring are consistently low in people with MS, stroke and dementia, and patterns of physical activity are altered in PD. In MS, decreased ambulatory activity assessed via remote monitoring is associated with greater disability and lower quality of life. In stroke, remote measures of upper limb function and ambulation are associated with functional recovery following rehabilitation and goal-directed interventions. In PD, remote monitoring may help to predict falls. In dementia, remote physical activity measures correlate with disease severity and can detect wandering. These studies show that remote physical activity monitoring is feasible in neurological diseases, including in people with moderate to severe neurological disability. Remote monitoring can be a psychometrically sound and responsive way to assess physical activity in neurological disease. Further research is needed to ensure these tools provide meaningful information in the context of specific neurological disorders and patterns of neurological disability.

  2. Computational prediction of the refinement of oxide agglomerates in a physical conditioning process for molten aluminium alloy

    International Nuclear Information System (INIS)

    Tong, M; Jagarlapudi, S C; Browne, D J; Patel, J B; Stone, I C; Fan, Z

    2015-01-01

    Physically conditioning molten scrap aluminium alloys using high shear processing (HSP) was recently found to be a promising technology for purification of contaminated alloys. HSP refines the solid oxide agglomerates in molten alloys, so that they can act as sites for the nucleation of Fe-rich intermetallic phases which can subsequently be removed by the downstream de-drossing process. In this paper, a computational modelling for predicting the evolution of size of oxide clusters during HSP is presented. We used CFD to predict the macroscopic flow features of the melt, and the resultant field predictions of temperature and melt shear rate were transferred to a population balance model (PBM) as its key inputs. The PBM is a macroscopic model that formulates the microscopic agglomeration and breakage of a population of a dispersed phase. Although it has been widely used to study conventional deoxidation of liquid metal, this is the first time that PBM has been used to simulate the melt conditioning process within a rotor/stator HSP device. We employed a method which discretizes the continuous profile of size of the dispersed phase into a collection of discrete bins of size, to solve the governing population balance equation for the size of agglomerates. A finite volume method was used to solve the continuity equation, the energy equation and the momentum equation. The overall computation was implemented mainly using the FLUENT module of ANSYS. The simulations showed that there is a relatively high melt shear rate between the stator and sweeping tips of the rotor blades. This high shear rate leads directly to significant fragmentation of the initially large oxide aggregates. Because the process of agglomeration is significantly slower than the breakage processes at the beginning of HSP, the mean size of oxide clusters decreases very rapidly. As the process of agglomeration gradually balances the process of breakage, the mean size of oxide clusters converges to a

  3. Clinical Prediction Rules for Physical Therapy Interventions: A Systematic Review

    Science.gov (United States)

    Beneciuk, Jason M; Bishop, Mark D; George, Steven Z

    2009-01-01

    Background and Purpose: Clinical prediction rules (CPRs) involving physical therapy interventions have been published recently. The quality of the studies used to develop the CPRs was not previously considered, a fact that has potential implications for clinical applications and future research. The purpose of this systematic review was to determine the quality of published CPRs developed for physical therapy interventions. Methods: Relevant databases were searched up to June 2008. Studies were included in this review if the explicit purpose was to develop a CPR for conditions commonly treated by physical therapists. Validated CPRs were excluded from this review. Study quality was independently determined by 3 reviewers using standard 18-item criteria for assessing the methodological quality of prognostic studies. Percentage of agreement was calculated for each criterion, and the intraclass correlation coefficient (ICC) was determined for overall quality scores. Results: Ten studies met the inclusion criteria and were included in this review. Percentage of agreement for individual criteria ranged from 90% to 100%, and the ICC for the overall quality score was .73 (95% confidence interval=.27–.92). Criteria commonly not met were adequate description of inclusion or exclusion criteria, inclusion of an inception cohort, adequate follow-up, masked assessments, sufficient sample sizes, and assessments of potential psychosocial factors. Quality scores for individual studies ranged from 48.2% to 74.0%. Discussion and Conclusion: Validation studies are rarely reported in the literature; therefore, CPRs derived from high-quality studies may have the best potential for use in clinical settings. Investigators planning future studies of physical therapy CPRs should consider including inception cohorts, using longer follow-up times, performing masked assessments, recruiting larger sample sizes, and incorporating psychological and psychosocial assessments. PMID:19095806

  4. Peer-Assisted Learning in School Physical Education, Sport and Physical Activity Programmes: A Systematic Review

    Science.gov (United States)

    Jenkinson, Kate. A.; Naughton, Geraldine; Benson, Amanda C.

    2014-01-01

    Background: Peer-assisted learning (PAL) is a teaching strategy utilised in both the general classroom and physical education. Through the interaction with same-age or cross-age peers, learning can occur across various domains. Purpose: This review aimed to identify school-based PAL interventions and assess the tutor training provided, as well as…

  5. Physical and mechanical metallurgy of zirconium alloys for nuclear applications: a multi-scale computational study

    Energy Technology Data Exchange (ETDEWEB)

    Glazoff, Michael Vasily [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-10-01

    In the post-Fukushima world, the stability of materials under extreme conditions is an important issue for the safety of nuclear reactors. Because the nuclear industry is going to continue using advanced zirconium cladding materials in the foreseeable future, it become critical to gain fundamental understanding of the several interconnected problems. First, what are the thermodynamic and kinetic factors affecting the oxidation and hydrogen pick-up by these materials at normal, off-normal conditions, and in long-term storage? Secondly, what protective coatings (if any) could be used in order to gain extremely valuable time at off-normal conditions, e.g., when temperature exceeds the critical value of 2200°F? Thirdly, the kinetics of oxidation of such protective coating or braiding needs to be quantified. Lastly, even if some degree of success is achieved along this path, it is absolutely critical to have automated inspection algorithms allowing identifying defects of cladding as soon as possible. This work strives to explore these interconnected factors from the most advanced computational perspective, utilizing such modern techniques as first-principles atomistic simulations, computational thermodynamics of materials, diffusion modeling, and the morphological algorithms of image processing for defect identification. Consequently, it consists of the four parts dealing with these four problem areas preceded by the introduction and formulation of the studied problems. In the 1st part an effort was made to employ computational thermodynamics and ab initio calculations to shed light upon the different stages of oxidation of ziraloys (2 and 4), the role of microstructure optimization in increasing their thermal stability, and the process of hydrogen pick-up, both in normal working conditions and in long-term storage. The 2nd part deals with the need to understand the influence and respective roles of the two different plasticity mechanisms in Zr nuclear alloys: twinning

  6. Elastic and thermo-physical properties of TiC, TiN, and their intermediate composition alloys using ab initio calculations

    International Nuclear Information System (INIS)

    Kim, Jiwoong; Kang, Shinhoo

    2012-01-01

    Highlights: ► Elastic properties of TiC, TiN and their alloys were calculated by ab initio calculations. ► Debye temperature and Gruneisen constant of TiC, TiN and their alloys were calculated as a function of nitrogen content. ► Thermo-physical properties were calculated as a function of nitrogen content. ► Thermal expansion of the alloys was fitted in different temperature range. - Abstract: The equilibrium lattice parameters, elastic properties, material brittleness, heat capacities, and thermal expansion coefficients of TiC, TiN, and their intermediate composition alloys (Ti(C 1−x N x ), x = 0.25, 0.5, and 0.75) were calculated using ab initio density functional theory (DFT) methods. We employed the Debye–Gruneisen model to calculate a finite temperature heat capacity and thermal expansion coefficient. The calculated elastic moduli and thermal expansion coefficients agreed well with the experimental data and with other DFT calculations. Accurate heat capacities of TiC, TiN, and their intermediate composition alloys were obtained by calculating not only the phonon contributions but also the electron contributions to the heat capacity. Our calculations indicated that the heat capacity differences between each composition originated mainly from the electronic contributions.

  7. Physical and cognitive consequences of fatigue: A review

    Directory of Open Access Journals (Sweden)

    Hoda M. Abd-Elfattah

    2015-05-01

    Full Text Available Fatigue is a common worrying complaint among people performing physical activities on the basis of training or rehabilitation. An enormous amount of research articles have been published on the topic of fatigue and its effect on physical and physiological functions. The goal of this review was to focus on the effect of fatigue on muscle activity, proprioception, and cognitive functions and to summarize the results to understand the influence of fatigue on these functions. Attaining this goal provides evidence and guidance when dealing with patients and/or healthy individuals in performing maximal or submaximal exercises.

  8. Influence of process parameters on physical dimensions of AA6063 aluminium alloy coating on mild steel in friction surfacing

    Directory of Open Access Journals (Sweden)

    B. Vijaya Kumar

    2015-09-01

    Full Text Available An attempt is made in the present study to obtain the relationships among process parameters and physical dimensions of AA6063 aluminium alloy coating on IS2062 mild steel obtained through friction surfacing and their impact on strength and ductility of the coating. Factorial experimental design technique was used to investigate and select the parameter combination to achieve a coating with adequate strength and ductility. Spindle speed, axial force and table traverse speed were observed to be the most significant factors on physical dimensions. It was observed that the thickness of the coating decreased as the coating width increased. In addition, the width and thickness of the coatings are higher at low and high torques. At intermediate torque values, when the force is high, the width of the coating is high, and its thickness is thin; and when the force is low, the width and thickness are low. The interaction effect between axial force (F – table traverse speed (Vx and spindle speed (N – table traverse speed (Vx produced an increasing effect on coating width and thickness, but other interactions exhibited decreasing influence. It has also been observed that sound coatings could be obtained in a narrow set of parameter range as the substrate-coating materials are metallurgically incompatible and have a propensity to form brittle intermetallics.

  9. Girls in the physics classroom: a review of the research on the participation of girls in physics

    OpenAIRE

    Murphy, Patricia; Whitelegg, Elizabeth

    2006-01-01

    A review of research spanning the past 15 years into the participation of girls in physics at secondary school level. The review was commissioned by the Institute of Physics in order to inform policy setting agendas for the Institute and to reveal important messages about participation in physics which the Institute could use to develop plans for action.

  10. Review of recent advances in high energy physics

    International Nuclear Information System (INIS)

    Hove, L. van

    1981-01-01

    This lecture reviews the main advances of high energy physics in the last decade, a period during which a number of major developments took place in our knowledge of the consituents of matter and of the basic laws of interaction. After a brief historical introduction, the lecture discusses quarks and leptons which are now recognized to be microscopic constituents of matter. It then proceeds with a review of recent progress concerning the electromagnetic, weak and strong interactions, both experimentally and theoretically. The trend towards unified theories of the basic interactions is discussed, in particular the so-called electroweak theory, which combines the electromagnetic and weak interactions. The lecture ends with remarks on novel aspects of the general theoretical situation, and with some considerations on the future outlook of high energy physics. (orig.)

  11. Measuring physical activity and sedentary behaviour at work: a review.

    Science.gov (United States)

    Castillo-Retamal, Marcelo; Hinckson, Erica A

    2011-01-01

    To identify methods used to assess physical activity and sedentary behaviour at the workplace and review the validity and reliability of these measures. Databases were searched for relevant published articles including MEDLINE, SPORT Discus, ProQuest and Google Scholar. Keywords used were physical-activity, workplace, sedentary-behaviour, measurement and questionnaire. Studies included were original, written in English, published between 1990 and 2009, and focused on validated physical activity and sedentary behaviour measures at work. Eleven papers were identified in which three used criterion standards, three objective measures, and five subjective measures. The most common method of data collection was through self-report, surveys or questionnaires. Physical activity measured with motion sensors, ranged from 4,422 to 10,334 steps/day (pedometers) and sedentary time ranged from 1.8 to 6 hours/day (h/d) (accelerometers). Self-report measures provided information relevant to the perception of physical activity at work (∼ 0.5 h/d), sitting time (> 3 h/d) and calculated energy expenditure (< 800 kcal/d). Physical activity levels at work were low while sedentary behaviour was high. This was largely a function of occupation (white-collar vs. blue-collar). None of the studies assessed validity or reliability of measures used however, instruments as assessed by others showed moderate to strong validity and reliability values.

  12. The physics of blackbody radiation: A review | Jain | JASSA: Journal ...

    African Journals Online (AJOL)

    The physics of blackbody radiation: A review. Pushpendra K Jain, Latit K Sharma. http://dx.doi.org/10.4314/jassa.v4i2.16899 · AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors · FAQ's · More about AJOL · AJOL's Partners · Terms and Conditions of Use · Contact AJOL · News.

  13. Electric sympathetic block: a review of electrotherapy physics.

    Science.gov (United States)

    Schwartz, R G

    1991-01-01

    Electric sympathetic block is the procedure whereby blockage of the sympathetic nerve fiber is achieved by applying controlled electrical pulses via electrodes placed on the skin. An electric block of the sympathetic fiber can occur with a direct monophasic current to achieve an anodal block, a middle-frequency or Endosan current to effect sustained depolarization, or an interferential current to achieve a fatiguing effect. The physics and theoretical framework underlying the currents used in this procedure will be reviewed.

  14. Eating disorders, physical fitness and sport performance: a systematic review.

    Science.gov (United States)

    El Ghoch, Marwan; Soave, Fabio; Calugi, Simona; Dalle Grave, Riccardo

    2013-12-16

    Eating disorders are health problems that are particularly prevalent in adolescents and young adults. They are associated with considerable physical health and psychosocial morbidity, and increased risk of mortality. We set out to conduct a systematic review to determine their effect on physical fitness in the general population and on sport performance in athletes. A systematic review of the relevant peer-reviewed literature was performed. For inclusion, articles retrieved from PubMed had to be published in English between 1977 and 2013. Wherever possible, methods and reporting adhere to the guidelines outlined in the PRISMA statement. Some additional studies were retrieved from among those cited in the reference lists of included studies and from non-electronic databases. Literature searches, study selection, method and quality appraisal were performed independently by two authors, and data was synthesized using a narrative approach. Of the 1183 articles retrieved, twenty-nine studies met the inclusion criteria and were consequently analysed. The available data indicate that eating disorders have a negative effect on physical fitness and sport performance by causing low energy availability, excessive loss of fat and lean mass, dehydration, and electrolyte disturbance. Although the paucity of the available data mean that findings to date should be interpreted with caution, the information collated in this review has several practical implications. First, eating disorders have a negative effect on both physical fitness and sport performance. Second athletics coaches should be targeted for education about the risk factors of eating disorders, as deterioration in sport performance in athletes, particularly if they are underweight or show other signs of an eating disorder, may indicate the need for medical intervention. However, future studies are needed, especially to assess the direct effect of eating disorders on sport performance.

  15. Eating Disorders, Physical Fitness and Sport Performance: A Systematic Review

    Science.gov (United States)

    El Ghoch, Marwan; Soave, Fabio; Calugi, Simona; Dalle Grave, Riccardo

    2013-01-01

    Background: Eating disorders are health problems that are particularly prevalent in adolescents and young adults. They are associated with considerable physical health and psychosocial morbidity, and increased risk of mortality. We set out to conduct a systematic review to determine their effect on physical fitness in the general population and on sport performance in athletes. Methods/Design: A systematic review of the relevant peer-reviewed literature was performed. For inclusion, articles retrieved from PubMed had to be published in English between 1977 and 2013. Wherever possible, methods and reporting adhere to the guidelines outlined in the PRISMA statement. Some additional studies were retrieved from among those cited in the reference lists of included studies and from non-electronic databases. Literature searches, study selection, method and quality appraisal were performed independently by two authors, and data was synthesized using a narrative approach. Results: Of the 1183 articles retrieved, twenty-nine studies met the inclusion criteria and were consequently analysed. The available data indicate that eating disorders have a negative effect on physical fitness and sport performance by causing low energy availability, excessive loss of fat and lean mass, dehydration, and electrolyte disturbance. Discussion: Although the paucity of the available data mean that findings to date should be interpreted with caution, the information collated in this review has several practical implications. First, eating disorders have a negative effect on both physical fitness and sport performance. Second athletics coaches should be targeted for education about the risk factors of eating disorders, as deterioration in sport performance in athletes, particularly if they are underweight or show other signs of an eating disorder, may indicate the need for medical intervention. However, future studies are needed, especially to assess the direct effect of eating disorders on

  16. Eating Disorders, Physical Fitness and Sport Performance: A Systematic Review

    Directory of Open Access Journals (Sweden)

    Marwan El Ghoch

    2013-12-01

    Full Text Available Background: Eating disorders are health problems that are particularly prevalent in adolescents and young adults. They are associated with considerable physical health and psychosocial morbidity, and increased risk of mortality. We set out to conduct a systematic review to determine their effect on physical fitness in the general population and on sport performance in athletes. Methods/Design: A systematic review of the relevant peer-reviewed literature was performed. For inclusion, articles retrieved from PubMed had to be published in English between 1977 and 2013. Wherever possible, methods and reporting adhere to the guidelines outlined in the PRISMA statement. Some additional studies were retrieved from among those cited in the reference lists of included studies and from non-electronic databases. Literature searches, study selection, method and quality appraisal were performed independently by two authors, and data was synthesized using a narrative approach. Results: Of the 1183 articles retrieved, twenty-nine studies met the inclusion criteria and were consequently analysed. The available data indicate that eating disorders have a negative effect on physical fitness and sport performance by causing low energy availability, excessive loss of fat and lean mass, dehydration, and electrolyte disturbance. Discussion: Although the paucity of the available data mean that findings to date should be interpreted with caution, the information collated in this review has several practical implications. First, eating disorders have a negative effect on both physical fitness and sport performance. Second athletics coaches should be targeted for education about the risk factors of eating disorders, as deterioration in sport performance in athletes, particularly if they are underweight or show other signs of an eating disorder, may indicate the need for medical intervention. However, future studies are needed, especially to assess the direct effect of

  17. Review of key concepts in magnetic resonance physics.

    Science.gov (United States)

    Moore, Michael M; Chung, Taylor

    2017-05-01

    MR physics can be a challenging subject for practicing pediatric radiologists. Although many excellent texts provide very comprehensive reviews of the field of MR physics at various levels of understanding, the authors of this paper explain several key concepts in MR physics that are germane to clinical practice in a non-rigorous but practical fashion. With the basic understanding of these key concepts, practicing pediatric radiologists can build on their knowledge of current clinical MR techniques and future advances in MR applications. Given the challenges of both the increased need for rapid imaging in non-sedated children and the rapid physiological cardiovascular and respiratory motion in pediatric patients, many advances in complex MR techniques are being applied to imaging these children. The key concepts are as follows: (1) structure of a pulse sequence, (2) k-space, (3) "trade-off triangle" and (4) fat suppression. This review is the first of five manuscripts in a minisymposium on pediatric MR. The authors' goal for this review is to aid in understanding the MR techniques described in the subsequent manuscripts on brain imaging and body imaging in this minisymposium.

  18. Review of key concepts in magnetic resonance physics

    Energy Technology Data Exchange (ETDEWEB)

    Moore, Michael M. [Penn State Hershey Children' s Hospital, Department of Radiology, The Pennsylvania State College of Medicine, Hershey, PA (United States); Chung, Taylor [UCSF Benioff Children' s Hospital Oakland, Department of Diagnostic Imaging, Oakland, CA (United States)

    2017-05-15

    MR physics can be a challenging subject for practicing pediatric radiologists. Although many excellent texts provide very comprehensive reviews of the field of MR physics at various levels of understanding, the authors of this paper explain several key concepts in MR physics that are germane to clinical practice in a non-rigorous but practical fashion. With the basic understanding of these key concepts, practicing pediatric radiologists can build on their knowledge of current clinical MR techniques and future advances in MR applications. Given the challenges of both the increased need for rapid imaging in non-sedated children and the rapid physiological cardiovascular and respiratory motion in pediatric patients, many advances in complex MR techniques are being applied to imaging these children. The key concepts are as follows: (1) structure of a pulse sequence, (2) k-space, (3) ''trade-off triangle'' and (4) fat suppression. This review is the first of five manuscripts in a minisymposium on pediatric MR. The authors' goal for this review is to aid in understanding the MR techniques described in the subsequent manuscripts on brain imaging and body imaging in this minisymposium. (orig.)

  19. Physical activity and cognition in the elderly: A review

    Directory of Open Access Journals (Sweden)

    Alexandre Leopold Busse

    Full Text Available Abstract Physical activity has been indicated as a strategy to promote health in the elderly, as well as to encourage the maintenance of functional capacity, and acts in the prevention and control of various diseases. In recent years, there has been great interest in studying the benefits of physical activity in the preservation or even improvement of cognitive performance in both the elderly without cognitive impairment and in elderly patients with some degree of cognitive impairment or dementia. The majority of epidemiological studies and clinical trials have evaluated aerobic exercises while few have assessed resistance exercise programs. The objective of this review was to examine the effects of different types of physical activity on cognitive function of elderly individuals with or without prior impairment.

  20. Review of lattice results concerning low-energy particle physics

    Energy Technology Data Exchange (ETDEWEB)

    Aoki, S. [Kyoto University, Center for Gravitational Physics, Yukawa Institute for Theoretical Physics, Kyoto (Japan); Aoki, Y. [Nagoya University, Kobayashi-Maskawa Institute for the Origin of Particles and the Universe (KMI), Nagoya (Japan); Brookhaven National Laboratory, RIKEN BNL Research Center, Upton, NY (United States); High Energy Accelerator Research Organization (KEK), Tsukuba (Japan); Becirevic, D. [Universite Paris-Sud, Universite Paris-Saclay, Laboratoire de Physique Theorique (UMR8627), CNRS, Orsay (France); Bernard, C. [Washington University, Department of Physics, Saint Louis, MO (United States); Blum, T. [Brookhaven National Laboratory, RIKEN BNL Research Center, Upton, NY (United States); University of Connecticut, Physics Department, Storrs, CT (United States); Colangelo, G.; Leutwyler, H.; Wenger, U. [Universitaet Bern, Albert Einstein Center for Fundamental Physics, Institut fuer Theoretische Physik, Bern (Switzerland); Della Morte, M. [University of Southern Denmark, CP3-Origins and Danish IAS, Odense M (Denmark); IFIC (CSIC), Paterna (Spain); Dimopoulos, P. [Centro Fermi-Museo Storico della Fisica e Centro Studi e Ricerche Enrico Fermi Compendio del Viminale, Rome (Italy); Universita di Roma Tor Vergata, c/o Dipartimento di Fisica, Rome (Italy); Duerr, S. [University of Wuppertal, Wuppertal (Germany); Juelich Supercomputing Center, Forschungszentrum Juelich, Juelich (Germany); Fukaya, H.; Onogi, T. [Osaka University, Department of Physics, Toyonaka, Osaka (Japan); Golterman, M. [San Francisco State University, Department of Physics and Astronomy, San Francisco, CA (United States); Gottlieb, Steven; Lunghi, E. [Indiana University, Department of Physics, Bloomington, IN (United States); Hashimoto, S.; Kaneko, T. [High Energy Accelerator Research Organization (KEK), Tsukuba (Japan); The Graduate University for Advanced Studies (Sokendai), School of High Energy Accelerator Science, Tsukuba (Japan); Heller, U.M. [American Physical Society (APS), Ridge, NY (United States); Horsley, R. [University of Edinburgh, Higgs Centre for Theoretical Physics, School of Physics and Astronomy, Edinburgh (United Kingdom); Juettner, A.; Sachrajda, C.T. [University of Southampton, School of Physics and Astronomy, Southampton (United Kingdom); Lellouch, L. [CNRS, Aix-Marseille Universite, Universite de Toulon, Centre de Physique Theorique, UMR 7332, Marseille (France); Lin, C.J.D. [CNRS, Aix-Marseille Universite, Universite de Toulon, Centre de Physique Theorique, UMR 7332, Marseille (France); National Chiao-Tung University, Institute of Physics, Hsinchu (China); Lubicz, V. [Universita Roma Tre, Dipartimento di Matematica e Fisica, Rome (Italy); INFN, Sezione di Roma Tre, Rome (Italy); Mawhinney, R. [Columbia University, Physics Department, New York, NY (United States); Pena, C. [Universidad Autonoma de Madrid, Departamento de Fisica Teorica, Instituto de Fisica Teorica UAM/CSIC, Madrid (Spain); Sharpe, S.R. [University of Washington, Physics Department, Seattle, WA (United States); Simula, S. [INFN, Sezione di Roma Tre, Rome (Italy); Sommer, R. [DESY, John von Neumann Institute for Computing (NIC), Zeuthen (Germany); Vladikas, A. [Universita di Roma ' ' Tor Vergata' ' , Dipartimento di Fisica, Rome (Italy); INFN, Rome (Italy); Wittig, H. [University of Mainz, PRISMA Cluster of Excellence, Institut fuer Kernphysik and Helmholtz Institute Mainz, Mainz (Germany); Collaboration: Flavour Lattice Averaging Group (FLAG)

    2017-02-15

    We review lattice results related to pion, kaon, D- and B-meson physics with the aim of making them easily accessible to the particle-physics community. More specifically, we report on the determination of the light-quark masses, the form factor f{sub +}(0), arising in the semileptonic K → π transition at zero momentum transfer, as well as the decay constant ratio f{sub K}/f{sub π} and its consequences for the CKM matrix elements V{sub us} and V{sub ud}. Furthermore, we describe the results obtained on the lattice for some of the low-energy constants of SU(2){sub L} x SU(2){sub R} and SU(3){sub L} x SU(3){sub R} Chiral Perturbation Theory. We review the determination of the B{sub K} parameter of neutral kaon mixing as well as the additional four B parameters that arise in theories of physics beyond the Standard Model. The latter quantities are an addition compared to the previous review. For the heavy-quark sector, we provide results for m{sub c} and m{sub b} (also new compared to the previous review), as well as those for D- and B-meson-decay constants, form factors, and mixing parameters. These are the heavy-quark quantities most relevant for the determination of CKM matrix elements and the global CKM unitarity-triangle fit. Finally, we review the status of lattice determinations of the strong coupling constant α{sub s}. (orig.)

  1. Effect of non-ionizing radio frequency signals of magnetic resonance imaging on physical properties of dental alloys and metal-ceramic adhesion.

    Science.gov (United States)

    El-Bediwi, Abu Bakr; El-Fallal, Abeer; Saker, Samah; Ozcan, Mutlu

    2014-10-01

    To assess the influence of non-ionizing radio frequency signals of magnetic resonance imaging (MRI) on physical properties of dental alloys and metal-ceramic adhesion. A total of 120 disk-shaped wax patterns (10 mm x 10 mm x 1 mm) were cast in a base metal alloy (Ni-Cr alloy) and commercially pure titanium (Ti) following the manufacturing recommendation. After casting, air abrasion and ultrasonic cleaning, feldspathic ceramic was applied and fired according to manufacturer's instructions using a standard mold. The specimens were subjected to 3000 thermocycles in distilled water between 5°C and 55°C, then veneered alloy specimens were randomly assigned to three groups according to MRI exposure time: a) 15 min of MRI exposure, b) 30 min of MRI exposure and c) no MRI exposure (control group). The specimens were subjected to shear loading until failure. A separate set of Ni-Cr and Ti specimens were prepared, and after exposure to MRI for 15 and 30 min, x-ray diffraction (XRD) analysis, surface roughness, and Vicker's hardness were measured. Both the alloy type (p < 0.005) and exposure duration (p < 0.005) had a significant effect on the bond results. While the control group presented the highest bond strength for Ni-Cr and Ti (36.9 ± 1.4 and 21.5 ± 1.6 MPa, respectively), 30 min MRI exposure significantly decreased the bond strength for both alloys (29.4 ± 1.5 and 12.8 ± 1.5 MPa, respectively) (p < 0.05). XRD analysis indicated formation of the crystalline phase as well as change in crystal size and position for Ni-Cr and Ti after MRI. Compared to the control group where alloys were not exposed to MRI (Ni-Cr: 0.40 μm; Ti: 0.17 μm), surface roughness increased (Ni-Cr: 0.54 μm; Ti: 1.1 μm). Vicker's hardness of both alloys decreased after 30 min MRI (Ni-Cr: 329.5; Ti: 216.1) compared to the control group c (Ni-Cr: 356.1; Ti: 662.1), being more significant for Ti (p < 0.005). Ni-Cr alloy is recommended over Ti for the fabrication of metal-ceramic restorations

  2. Nutrition habits, physical activity, and lung cancer: an authoritative review.

    Science.gov (United States)

    Koutsokera, Alexandra; Kiagia, Maria; Saif, Muhammad W; Souliotis, Kyriakos; Syrigos, Kostas N

    2013-07-01

    Lung cancer is the leading cause of cancer death worldwide. Because of high incidence rates and low survival rates, it is important to study the risk factors that may help prevent the disease from developing. It has been well established that cigarette smoking is the most important risk factor for lung cancer. Nonetheless it is likely that there are other modifiable risk factors that would assist in the prevention of lung cancer. Research on factors such as nutrition and physical activity and their influence on lung cancer has been carried out for nearly 3 decades. A systematic review in the MEDLINE database of published studies was conducted, focusing on systematic reviews, meta-analyses, and large prospective studies. The association between physical activity and lung cancer has been conflicting. Among the researched studies, 10 showed an inverse association, whereas 11 reported no association. A meta-analysis that was conducted from 1996 to October 2003 showed that leisure physical activity (LPA) prevents lung cancer. Data from 11 cohort and case-control studies showed an inverse relationship between fruit and vegetable consumption and lung cancer. Evidence from case-control studies suggests a positive association between meat intake and risk of lung cancer, although several more recent studies have presented doubts about these findings. The possible association of physical activity, nutrition, and the risk of lung cancer development remains controversial. Further prospective studies should be conducted to determine the potential influence of these 2 risk factors. Copyright © 2013 Elsevier Inc. All rights reserved.

  3. Review of properties of magnetic shape memory (MSM) alloys and MSM actuator designs

    International Nuclear Information System (INIS)

    Gabdullin, N; Khan, S H

    2015-01-01

    Magnetic shape memory alloys are a new group of ''smart'' materials that exhibit large strain of 6-12% when subjected to magnetic fields. This indicates their enormous potential to be used in different electromagnetic (EM) devices such as actuators, sensors, energy harvesters and dampers. Shape change in MSM materials is controlled by magnetic field and doesn't involve phase transformation, allowing it to overcome a number of disadvantages of conventional shape memory alloys (SMAs). MSM devices are capable of producing large force and stroke output in considerably small dimensions. At the same time they can have fast response and potentially very long lifetime. This paper discusses different modern designs and approaches to MSM actuator design with their advantages and disadvantages. An overview on characteristics of MSM alloys is also presented in order to highlight how different properties of the material influence the total output of a device

  4. X-ray diffraction during study of short-range order in amorphous alloys (Review)

    International Nuclear Information System (INIS)

    Shelekhov, E.V.; Skakov, Yu.A.

    1988-01-01

    Conditions for amorphous solidification of metallic system many alloys have been investigated and material compositions with peculiar set of properties have been chosen due to the intensive researches, conducted recently. Amorphous alloys, which combine magnetically soft properties with high wear resistance, are used more extensively among these materials. Analysis of X-ray diffuse scattering by amorphous alloys, using diffractometer, is more available and popular in spite of the presence of energy-dispersion method and neutron diffraction analysis. It should be noted, that low-cost isotopes with neutrons scattering amplitude, which differs essentially from that of their natural mixture, do not exist for all these elements. That is why, it is necessary to use X-ray diffractometry to separate distribution partial functions as well

  5. High-pressure coolant effect on the surface integrity of machining titanium alloy Ti-6Al-4V: a review

    Science.gov (United States)

    Liu, Wentao; Liu, Zhanqiang

    2018-03-01

    Machinability improvement of titanium alloy Ti-6Al-4V is a challenging work in academic and industrial applications owing to its low thermal conductivity, low elasticity modulus and high chemical affinity at high temperatures. Surface integrity of titanium alloys Ti-6Al-4V is prominent in estimating the quality of machined components. The surface topography (surface defects and surface roughness) and the residual stress induced by machining Ti-6Al-4V occupy pivotal roles for the sustainability of Ti-6Al-4V components. High-pressure coolant (HPC) is a potential choice in meeting the requirements for the manufacture and application of Ti-6Al-4V. This paper reviews the progress towards the improvements of Ti-6Al4V surface integrity under HPC. Various researches of surface integrity characteristics have been reported. In particularly, surface roughness, surface defects, residual stress as well as work hardening are investigated in order to evaluate the machined surface qualities. Several coolant parameters (including coolant type, coolant pressure and the injection position) deserve investigating to provide the guidance for a satisfied machined surface. The review also provides a clear roadmap for applications of HPC in machining Ti-6Al4V. Experimental studies and analysis are reviewed to better understand the surface integrity under HPC machining process. A distinct discussion has been presented regarding the limitations and highlights of the prospective for machining Ti-6Al4V under HPC.

  6. A Review of Solid-Solution Models of High-Entropy Alloys Based on Ab Initio Calculations

    Directory of Open Access Journals (Sweden)

    Fuyang Tian

    2017-11-01

    Full Text Available Similar to the importance of XRD in experiments, ab initio calculations, as a powerful tool, have been applied to predict the new potential materials and investigate the intrinsic properties of materials in theory. As a typical solid-solution material, the large degree of uncertainty of high-entropy alloys (HEAs results in the difficulty of ab initio calculations application to HEAs. The present review focuses on the available ab initio based solid-solution models (virtual lattice approximation, coherent potential approximation, special quasirandom structure, similar local atomic environment, maximum-entropy method, and hybrid Monte Carlo/molecular dynamics and their applications and limits in single phase HEAs.

  7. Review of lattice results concerning low-energy particle physics.

    Science.gov (United States)

    Aoki, S; Aoki, Y; Bernard, C; Blum, T; Colangelo, G; Della Morte, M; Dürr, S; El-Khadra, A X; Fukaya, H; Horsley, R; Jüttner, A; Kaneko, T; Laiho, J; Lellouch, L; Leutwyler, H; Lubicz, V; Lunghi, E; Necco, S; Onogi, T; Pena, C; Sachrajda, C T; Sharpe, S R; Simula, S; Sommer, R; Van de Water, R S; Vladikas, A; Wenger, U; Wittig, H

    We review lattice results related to pion, kaon, [Formula: see text]- and [Formula: see text]-meson physics with the aim of making them easily accessible to the particle-physics community. More specifically, we report on the determination of the light-quark masses, the form factor [Formula: see text], arising in semileptonic [Formula: see text] transition at zero momentum transfer, as well as the decay-constant ratio [Formula: see text] of decay constants and its consequences for the CKM matrix elements [Formula: see text] and [Formula: see text]. Furthermore, we describe the results obtained on the lattice for some of the low-energy constants of [Formula: see text] and [Formula: see text] Chiral Perturbation Theory and review the determination of the [Formula: see text] parameter of neutral kaon mixing. The inclusion of heavy-quark quantities significantly expands the FLAG scope with respect to the previous review. Therefore, we focus here on [Formula: see text]- and [Formula: see text]-meson decay constants, form factors, and mixing parameters, since these are most relevant for the determination of CKM matrix elements and the global CKM unitarity-triangle fit. In addition we review the status of lattice determinations of the strong coupling constant [Formula: see text].

  8. Review of lattice results concerning low-energy particle physics

    Energy Technology Data Exchange (ETDEWEB)

    Aoki, S. [Kyoto University, Yukawa Institute for Theoretical Physics, Kyoto (Japan); Aoki, Y. [Nagoya University, Kobayashi-Maskawa Institute for the Origin of Particles and the Universe (KMI), Nagoya (Japan); Brookhaven National Laboratory, RIKEN BNL Research Center, Upton, NY (United States); Bernard, C. [Washington University, Department of Physics, Saint Louis, MO (United States); Blum, T. [Brookhaven National Laboratory, RIKEN BNL Research Center, Upton, NY (United States); University of Connecticut, Physics Department, Storrs, CT (United States); Colangelo, G.; Leutwyler, H.; Necco, S.; Wenger, U. [Institut fuer theoretische Physik, Universitaet Bern, Albert Einstein Center for Fundamental Physics, Bern (Switzerland); Della Morte, M. [University of Southern Denmark, CP3-Origins and Danish IAS, Odense M (Denmark); IFIC (CSIC), Paterna (Spain); Duerr, S. [Bergische Universitaet Wuppertal, Wuppertal (Germany); Juelich Supercomputing Center, Juelich (Germany); El-Khadra, A.X. [University of Illinois, Department of Physics, Urbana, IL (United States); Fukaya, H.; Onogi, T. [Osaka University, Department of Physics, Osaka (Japan); Horsley, R. [University of Edinburgh, School of Physics, Edinburgh (United Kingdom); Juettner, A.; Sachrajda, C.T. [University of Southampton, School of Physics and Astronomy, Southampton (United Kingdom); Kaneko, T. [High Energy Accelerator Research Organization (KEK), Ibaraki (Japan); Laiho, J. [University of Glasgow, SUPA, Department of Physics and Astronomy, Glasgow (United Kingdom); Syracuse University, Department of Physics, Syracuse, New York (United States); Lellouch, L. [Aix-Marseille Universite, CNRS, CPT, UMR 7332, Marseille (France); Universite de Toulon, CNRS, CPT, UMR 7332, La Garde (France); Lubicz, V. [Universita Roma Tre, Dipartimento di Matematica e Fisica, Rome (Italy); Sezione di Roma Tre, INFN, Rome (Italy); Lunghi, E. [Indiana University, Physics Department, Bloomington, IN (United States); Pena, C. [Universidad Autonoma de Madrid, Instituto de Fisica Teorica UAM/CSIC and Departamento de Fisica Teorica, Madrid (Spain); Sharpe, S.R. [University of Washington, Physics Department, Seattle, WA (United States); Simula, S. [Sezione di Roma Tre, INFN, Rome (Italy); Sommer, R. [NIC rate at DESY, Zeuthen (Germany); Water, R.S.V. de [Fermi National Accelerator Laboratory, Batavia, IL (United States); Vladikas, A. [Universita di Roma Tor Vergata, INFN, Sezione di Tor Vergata, c/o Dipartimento di Fisica, Rome (Italy); Wittig, H. [University of Mainz, PRISMA Cluster of Excellence, Institut fuer Kernphysik and Helmholtz Institute Mainz, Mainz (Germany); Collaboration: FLAG Working Group

    2014-09-15

    We review lattice results related to pion, kaon, D- and B-meson physics with the aim of making them easily accessible to the particle-physics community. More specifically, we report on the determination of the lightquark masses, the form factor f{sub +}(0), arising in semileptonic K → π transition at zero momentum transfer, as well as the decay-constant ratio f{sub K}/f{sub π} of decay constants and its consequences for the CKM matrix elements V{sub us} and V{sub ud}. Furthermore, we describe the results obtained on the lattice for some of the low-energy constants of SU(2){sub L} x SU(2){sub R} andSU(3)L{sub L} x SU(3){sub R} Chiral Perturbation Theory and review the determination of the BK parameter of neutral kaon mixing. The inclusion of heavy-quark quantities significantly expands the FLAG scope with respect to the previous review. Therefore, we focus here on D- and B-meson decay constants, form factors, and mixing parameters, since these are most relevant for the determination of CKM matrix elements and the global CKM unitarity-triangle fit. In addition we review the status of lattice determinations of the strong coupling constant α{sub s}. (orig.)

  9. TOPICAL REVIEW: The physics, biophysics and technology of photodynamic therapy

    Science.gov (United States)

    Wilson, Brian C.; Patterson, Michael S.

    2008-05-01

    Photodynamic therapy (PDT) uses light-activated drugs to treat diseases ranging from cancer to age-related macular degeneration and antibiotic-resistant infections. This paper reviews the current status of PDT with an emphasis on the contributions of physics, biophysics and technology, and the challenges remaining in the optimization and adoption of this treatment modality. A theme of the review is the complexity of PDT dosimetry due to the dynamic nature of the three essential components—light, photosensitizer and oxygen. Considerable progress has been made in understanding the problem and in developing instruments to measure all three, so that optimization of individual PDT treatments is becoming a feasible target. The final section of the review introduces some new frontiers of research including low dose rate (metronomic) PDT, two-photon PDT, activatable PDT molecular beacons and nanoparticle-based PDT.

  10. Review of alkali metal and refractory alloy compatibility for Rankine cycle applications

    International Nuclear Information System (INIS)

    DiStefano, J.R.

    1989-01-01

    The principal corrosion mechanisms in refractory metal-alkali systems are dissolution, mass transfer, and impurity reactions. In general, niobium, tantalum, molybdenum, and tungsten have low solubilities in the alkali metals, even to very high temperatures, and static corrosion studies have verified that the systems are basically compatible. Loop studies with niobium and tantalum based alloys do not indicate any serious problems due to temperature gradient mass transfer. Above 1000 K, dissimilar metal mass transfer is noted between the refractory metals and iron or nickel based alloys. The most serious corrosion problems encountered are related to impurity reactions associated with oxygen

  11. Physical properties of the FeRh alloys: the antiferromagnetic to ferromagnetic transition

    Czech Academy of Sciences Publication Activity Database

    Kudrnovský, Josef; Drchal, Václav; Turek, I.

    2015-01-01

    Roč. 91, č. 1 (2015), "014435-1"-"014435-11" ISSN 1098-0121 R&D Projects: GA ČR GB14-37427G Institutional support: RVO:68378271 Keywords : coherent-potential approximation * phase-transformations Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.736, year: 2014

  12. Physical Activity Assessment During Gestation and Its Outcomes: A Review.

    Science.gov (United States)

    Forczek, Wanda; Curyło, Marta; Forczek, Barbara

    2017-07-01

    Physical activity recommendations emphasize a positive influence of exercise on health. It is particularly recognized during pregnancy for both the mother and fetus. This review aims to identify the main trends of activity undertaken by women during gestation and to find out how it affects the expecting mother and her child. Review of the literature comprising the following databases: PubMed, Academic Search Complete, Health Source-Consumer Edition, Health Source: Nursing/Academic Edition, EMBASE (2000 to May 2013), used detailed search strategies. The review was restricted to experimental studies. Trials were excluded if they met any of the following criteria: reviews, letters, commentaries or editorials, only abstracts available, and any kind of pathology during pregnancy. Three assessors reviewed the titles, abstracts, and full articles using standardized data abstraction forms, and they assessed the study quality. A total of 474 potential articles remained for analyses. Twenty-eight articles were eligible for inclusion in the present review: randomized controlled trials and observational studies that evaluated maternal and offspring outcomes as a result of physical activity during pregnancy. Quasi-randomized trials were excluded. The activities that were most frequently assessed included occupational activity, housework/caregiving, sport/exercise, and active living, as well as habits. The authors evaluated different types of physical activity in the loading conditions. The aerobic activities most frequently used for assessment included treadmill walking program; step aerobics or stair stepper; aerobics; bicycle ergometer; combination of rowing, stationary cycling, and walk jogging; rhythmic calisthenics class and step class; brisk walks; stretching; and relaxation. The benefits following being active during pregnancy are associated with improved maternal psychological well-being, a reduced risk of preterm birth and excessive gestational weight gain, and lower

  13. Refractory alloy technology for space nuclear power applications

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, R.H. Jr.; Hoffman, E.E. (eds.)

    1984-01-01

    Purpose of this symposium is twofold: (1) to review and document the status of refractory alloy technology for structural and fuel-cladding applications in space nuclear power systems, and (2) to identify and document the refractory alloy research and development needs for the SP-100 Program in both the short and the long term. In this symposium, an effort was made to recapture the space reactor refractory alloy technology that was cut off in midstream around 1973 when the national space nuclear reactor program began in the early 1960s, was terminated. The six technical areas covered in the program are compatibility, processing and production, welding and component fabrication, mechanical and physical properties, effects of irradiation, and machinability. The refractory alloys considered are niobium, molybdenum, tantalum, and tungsten. Thirteen of the 14 pages have been abstracted separately. The remaining paper summarizes key needs for further R and D on refractory alloys. (DLC)

  14. Refractory alloy technology for space nuclear power applications

    International Nuclear Information System (INIS)

    Cooper, R.H. Jr.; Hoffman, E.E.

    1984-01-01

    Purpose of this symposium is twofold: (1) to review and document the status of refractory alloy technology for structural and fuel-cladding applications in space nuclear power systems, and (2) to identify and document the refractory alloy research and development needs for the SP-100 Program in both the short and the long term. In this symposium, an effort was made to recapture the space reactor refractory alloy technology that was cut off in midstream around 1973 when the national space nuclear reactor program began in the early 1960s, was terminated. The six technical areas covered in the program are compatibility, processing and production, welding and component fabrication, mechanical and physical properties, effects of irradiation, and machinability. The refractory alloys considered are niobium, molybdenum, tantalum, and tungsten. Thirteen of the 14 pages have been abstracted separately. The remaining paper summarizes key needs for further R and D on refractory alloys

  15. Nuts for Physical Health and Fitness: A Review

    Directory of Open Access Journals (Sweden)

    Hidetaka Hamasaki

    2017-11-01

    Full Text Available Nuts are rich in various nutrients. Recent evidence suggests that nut consumption has beneficial effects on blood pressure, lipid profile, obesity, inflammation, and oxidative stress, which reduce the risk of cardiovascular disease. Previous studies have shown that nut consumption improves body composition without causing weight gain, despite total energy intake increases. However, evidence regarding nut consumption and physical fitness is limited. The aim of this mini review is to summarize the evidence regarding effects of nuts on physical health, fitness, and exercise performance. Almond supplementation improves exercise performance, but pistachio supplementation does not. The effect of nuts on exercise performance was controversial. On the other hand, unsaturated fatty acid-enriched nuts had a beneficial effect on skeletal muscle mass and oxygen consumption. A diet enriched with nuts also improved physical fitness, which was enhanced by exercise. Although the characteristics of the study participants and the interventions used in the studies are heterogeneous, nuts have a potential to improve physical fitness. However, further studies are required to reveal the effects of nuts on physical fitness, exercise performance, and endurance capacity.

  16. Influence of an alloy addition on the physical and clinical behaviour of glass ionomer cement

    Science.gov (United States)

    Abour, Mohamed Abour Bashir

    comparative evaluation of Hi-Dense with a disperse phase alloy placed as Class I restoration, the indirect assessment showed that Hi-Dense showed greater wear at six months than the amalgam using Ivoclar method of model assessment of wear. These studies indicate that the incorporation of a metal addition in the glass ionomer may have brought about a slight improvement in some of the properties tested. However, the performance of the experimental material with similar high powder content but no metal addition indicates that the use of a high powder content may be the predominant cause for the possible improvement.

  17. Additive manufacturing of metals: a brief review of the characteristic microstructures and properties of steels, Ti-6Al-4V and high-entropy alloys

    Science.gov (United States)

    Gorsse, Stéphane; Hutchinson, Christopher; Gouné, Mohamed; Banerjee, Rajarshi

    2017-01-01

    Abstract We present a brief review of the microstructures and mechanical properties of selected metallic alloys processed by additive manufacturing (AM). Three different alloys, covering a large range of technology readiness levels, are selected to illustrate particular microstructural features developed by AM and clarify the engineering paradigm relating process–microstructure–property. With Ti-6Al-4V the emphasis is placed on the formation of metallurgical defects and microstructures induced by AM and their role on mechanical properties. The effects of the large in-built dislocation density, surface roughness and build atmosphere on mechanical and damage properties are discussed using steels. The impact of rapid solidification inherent to AM on phase selection is highlighted for high-entropy alloys. Using property maps, published mechanical properties of additive manufactured alloys are graphically summarized and compared to conventionally processed counterparts. PMID:28970868

  18. Additive manufacturing of metals: a brief review of the characteristic microstructures and properties of steels, Ti-6Al-4V and high-entropy alloys.

    Science.gov (United States)

    Gorsse, Stéphane; Hutchinson, Christopher; Gouné, Mohamed; Banerjee, Rajarshi

    2017-01-01

    We present a brief review of the microstructures and mechanical properties of selected metallic alloys processed by additive manufacturing (AM). Three different alloys, covering a large range of technology readiness levels, are selected to illustrate particular microstructural features developed by AM and clarify the engineering paradigm relating process-microstructure-property. With Ti-6Al-4V the emphasis is placed on the formation of metallurgical defects and microstructures induced by AM and their role on mechanical properties. The effects of the large in-built dislocation density, surface roughness and build atmosphere on mechanical and damage properties are discussed using steels. The impact of rapid solidification inherent to AM on phase selection is highlighted for high-entropy alloys. Using property maps, published mechanical properties of additive manufactured alloys are graphically summarized and compared to conventionally processed counterparts.

  19. Review criteria for the physical fitness training requirements in 10 CFR Part 73

    International Nuclear Information System (INIS)

    Brown, C.

    1994-09-01

    This document provides review criteria that will be used in reviewing and approving revised physical security plans submitted by licensees which are required to meet the physical fitness requirements in 10 CFR Part 73

  20. Physical activity and older adults : a review of health benefits and the effectiveness of interventions

    NARCIS (Netherlands)

    Taylor, AH; Cable, NT; Faulkner, G; Hillsdon, M; Narici, M

    The purpose of this multidisciplinary review paper is to critically review evidence from descriptive, efficacy and effectiveness studies concerned with physical activity and older people. Both levels of fitness (aerobic power, strength, flexibility and functional capability) and measures of physical

  1. Physical activity and older adults: a review of health benefits and the effectiveness of interventions.

    NARCIS (Netherlands)

    Taylor, A.H.; Cable, N.T.; Faulkner, G.; Hillsdon, M.; Narici, M.; Bij, A.K. van der

    2004-01-01

    The purpose of this multidisciplinary review paper is to critically review evidence from descriptive, efficacy and effectiveness studies concerned with physical activity and older people. Both levels of fitness (aerobic power, strength, flexibility and functional capability) and measures of physical

  2. Biocompatibility of dental alloys

    Energy Technology Data Exchange (ETDEWEB)

    Braemer, W. [Heraeus Kulzer GmbH and Co. KG, Hanau (Germany)

    2001-10-01

    Modern dental alloys have been used for 50 years to produce prosthetic dental restorations. Generally, the crowns and frames of a prosthesis are prepared in dental alloys, and then veneered by feldspar ceramics or composites. In use, the alloys are exposed to the corrosive influence of saliva and bacteria. Metallic dental materials can be classified as precious and non-precious alloys. Precious alloys consist of gold, platinum, and small amounts of non-precious components such as copper, tin, or zinc. The non-precious alloys are based on either nickel or cobalt, alloyed with chrome, molybdenum, manganese, etc. Titanium is used as Grade 2 quality for dental purposes. As well as the dental casting alloys, high purity electroplated gold (99.8 wt.-%) is used in dental technology. This review discusses the corrosion behavior of metallic dental materials with saliva in ''in vitro'' tests and the influence of alloy components on bacteria (Lactobacillus casei and Streptococcus mutans). The test results show that alloys with high gold content, cobalt-based alloys, titanium, and electroplated gold are suitable for use as dental materials. (orig.)

  3. Stages of change toward physical activity: a review of literature

    Directory of Open Access Journals (Sweden)

    Samuel de Carvalho Dumith

    2008-07-01

    Full Text Available http://dx.doi.org/10.5007/1980-0037.2008v10n3p301 The aim of the present study was to carry out a review of the literature about studies that investigated the stages of change for physical activity among adults. The search was conducted in the following electronic databases: Medline/Pubmed, Web of Science, Ovid, Biomed Central, Elsevier, Oxford, Sports Discus, PsycInfo e Lilacs. The terms used were: “transtheoretical model”, “stages of change”, “stages of readiness” combined with “physical activity” or “exercise”; when appropriated, the equivalent terms in Portuguese were used. Only original or reviews articles were selected, and other type of works were excluded. The issues discussed in this article addressed the background and the temporal evolution of the stages of change, ways of operationalize and analyze the stages, validity and reliability of the instruments applied to measure the stages, and the factors associated with the stages. In conclusion, the importance of the stages of change model to promote physical activity practice was highlighted.

  4. The physical environment and child development: an international review.

    Science.gov (United States)

    Ferguson, Kim T; Cassells, Rochelle C; MacAllister, Jack W; Evans, Gary W

    2013-01-01

    A growing body of research in the United States and Western Europe documents significant effects of the physical environment (toxins, pollutants, noise, crowding, chaos, and housing, school and neighborhood quality) on children and adolescents' cognitive and socioemotional development. Much less is known about these relations in other contexts, particularly the global South. We thus briefly review the evidence for relations between child development and the physical environment in Western contexts, and discuss some of the known mechanisms behind these relations. We then provide a more extensive review of the research to date outside of Western contexts, with a specific emphasis on research in the global South. Where the research is limited, we highlight relevant data documenting the physical environment conditions experienced by children, and make recommendations for future work. In these recommendations, we highlight the limitations of employing research methodologies developed in Western contexts (Ferguson & Lee, 2013). Finally, we propose a holistic, multidisciplinary, and multilevel approach based on Bronfenbrenner's (1979) bioecological model to better understand and reduce the aversive effects of multiple environmental risk factors on the cognitive and socioemotional development of children across the globe.

  5. Physical environmental correlates of childhood obesity: a systematic review.

    Science.gov (United States)

    Dunton, G F; Kaplan, J; Wolch, J; Jerrett, M; Reynolds, K D

    2009-07-01

    Increasing rates of childhood obesity in the USA and other Western countries are a cause for serious public health concern. Neighborhood and community environments are thought to play a contributing role in the development of obesity among youth, but it is not well understood which types of physical environmental characteristics have the most potential to influence obesity outcomes. This paper reports the results of a systematic review of quantitative research examining built and biophysical environmental variables associated with obesity in children and adolescents through physical activity. Literature searches in PubMed, PsychInfo and Geobase were conducted. Fifteen quantitative studies met the inclusion criteria for this systematic review. The majority of studies were cross-sectional and published after 2005. Overall, few consistent findings emerged. For children, associations between physical environmental variables and obesity differed by gender, age, socioeconomic status, population density and whether reports were made by the parent or child. Access to equipment and facilities, neighborhood pattern (e.g. rural, exurban, suburban) and urban sprawl were associated with obesity outcomes in adolescents. For most environmental variables considered, strong empirical evidence is not yet available. Conceptual gaps, methodological limitations and future research directions are discussed.

  6. Review of lattice results concerning low energy particle physics

    CERN Document Server

    Colangelo, Gilberto; Juttner, Andreas; Lellouch, Laurent; Leutwyler, Heinrich; Lubicz, Vittorio; Necco, Silvia; Sachrajda, Christopher T; Simula, Silvano; Vladikas, Anastassios; Wenger, Urs; Wittig, Hartmut

    2011-01-01

    We review lattice results relevant for pion and kaon physics with the aim of making them easily accessible to the particle physics community. Specifically, we review the determination of the light-quark masses, the form factor f_+(0), relevant for the semileptonic K -> pi transition at zero momentum transfer as well as the ratio f_K/f_pi of decay constants and discuss the consequences for the elements V_{us} and V_{ud} of the CKM matrix. Furthermore, we describe the results obtained on the lattice for some of the low-energy constants of SU(2)_LxSU(2)_R and SU(3)_LxSU(3)_R Chiral Perturbation Theory and review the determination of the B_K parameter of neutral kaon mixing. We introduce quality criteria and use these when forming averages. Although subjective and imperfect, these criteria may help the reader to judge different aspects of current lattice computations. Our main results are summarized in section 1.2, but we stress the importance of the detailed discussion that underlies these results and constitute...

  7. The physical impacts of microplastics on marine organisms: A review

    International Nuclear Information System (INIS)

    Wright, Stephanie L.; Thompson, Richard C.; Galloway, Tamara S.

    2013-01-01

    Plastic debris at the micro-, and potentially also the nano-scale, are widespread in the environment. Microplastics have accumulated in oceans and sediments worldwide in recent years, with maximum concentrations reaching 100 000 particles m 3 . Due to their small size, microplastics may be ingested by low trophic fauna, with uncertain consequences for the health of the organism. This review focuses on marine invertebrates and their susceptibility to the physical impacts of microplastic uptake. Some of the main points discussed are (1) an evaluation of the factors contributing to the bioavailability of microplastics including size and density; (2) an assessment of the relative susceptibility of different feeding guilds; (3) an overview of the factors most likely to influence the physical impacts of microplastics such as accumulation and translocation; and (4) the trophic transfer of microplastics. These findings are important in guiding future marine litter research and management strategies. -- Highlights: •Accumulation of plastic waste in the oceans has become a pressing issue. •Here we review the susceptibility of marine invertebrates to microplastic uptake. •Size, shape and abundance influence uptake; microfibres are considered most harmful. •Colonisation of microplastics could have population-level impacts. •Results will inform future marine litter research and management strategies. -- Here we review microplastic uptake in marine organisms and assess individual, population and community level effects, highlighting the most susceptible species

  8. Physical activity and biological maturation: a systematic review

    Directory of Open Access Journals (Sweden)

    Eliane Denise Araújo Bacil

    2015-03-01

    Full Text Available OBJECTIVE: To analyze the association between physical activity (PA and biological maturation in children and adolescents. DATA SOURCE: We performed a systematic review in April 2013 in the electronic databases of PubMed/MEDLINE, SportDiscus, Web of Science and LILACS without time restrictions. A total of 628 potentially relevant articles were identified and 10 met the inclusion criteria for this review: cross-sectional or longitudinal studies, published in Portuguese, English or Spanish, with schoolchildren aged 9-15 years old of both genders. DATA SYNTHESIS: Despite the heterogeneity of the studies, there was an inverse association between PA and biological maturation. PA decreases with increased biological and chronological age in both genders. Boys tend to be more physically active than girls; however, when controlling for biological age, the gender differences disappear. The association between PA and timing of maturation varies between the genders. Variation in the timing of biological maturation affects the tracking of PA in early adolescent girls. This review suggests that mediators (BMI, depression, low self-esteem, and concerns about body weight can explain the association between PA and biological maturation. CONCLUSIONS: There is an association between PA and biological maturation. PA decreases with increasing biological age with no differences between genders. As for the timing of biological maturation, this association varies between genders.

  9. Physical Activity and Cognitive Functioning of Children: A Systematic Review

    Directory of Open Access Journals (Sweden)

    Ilona Bidzan-Bluma

    2018-04-01

    Full Text Available Childhood is an important and sensitive period for cognitive development. There is limited published research regarding the relationship between sports and cognitive functions in children. We present studies that demonstrate the influence of physical activity on health, especially a positive correlation between sports and cognitive functions. The keywords “children, cognition, cognitive function, physical activity, and brain” were searched for using PsycInfo, Medline, and Google Scholar, with publication dates ranging from January 2000 to November 2017. Of the 617 results, 58 articles strictly connected to the main topics of physical activity and cognitive functioning were then reviewed. The areas of attention, thinking, language, learning, and memory were analyzed relative to sports and childhood. Results suggest that engaging in sports in late childhood positively influences cognitive and emotional functions. There is a paucity of publications that investigate the impact of sports on pre-adolescents’ cognitive functions, or explore which cognitive functions are developed by which sporting disciplines. Such knowledge would be useful in developing training programs for pre-adolescents, aimed at improving cognitive functions that may guide both researchers and practitioners relative to the wide range of benefits that result from physical activity.

  10. [Recommendations for physical exercise practice during pregnancy: a critical review].

    Science.gov (United States)

    do Nascimento, Simony Lira; Godoy, Ana Carolina; Surita, Fernanda Garanhani; Pinto e Silva, João Luiz

    2014-09-01

    Physical exercise is recommended for all healthy pregnant women. Regular practice of exercises during pregnancy can provide many physical and psychological benefits, with no evidence of adverse outcomes for the fetus or the newborn when exercise is performed at mild to moderate intensity. However, few pregnant women engage in this practice and many still have fears and doubts about the safety of exercise. The objective of the present study was to inform the professionals who provide care for Brazilian pregnant women about the current recommendations regarding physical exercise during pregnancy based on the best scientific evidence available. In view of the perception that few systematic models are available about this topic and after performing several studies in this specific area, we assembled practical information of interest to both the professionals and the pregnant women. We also provide recommendations about the indications, contraindications, modalities (aerobics, resistance training, stretching and pelvic floor training), frequency, intensity and duration indicated for each gestational trimester. The review addresses physical exercise recommendation both for low risk pregnant women and for special populations, such as athletes and obese, hypertensive and diabetic subjects. The advantages of an active and healthy lifestyle should be always reinforced during and after gestation since pregnancy is an appropriate period to introduce new habits because pregnant women are usually more motivated to adhere to recommendations. Thus, routine exams, frequent returns and supervision are recommended in order to provide new guidelines that will have long-term beneficial effects for both mother and child.

  11. A Review of Cyber-Physical Energy System Security Assessment

    DEFF Research Database (Denmark)

    Rasmussen, Theis Bo; Yang, Guangya; Nielsen, Arne Hejde

    2017-01-01

    to the consumption side. This transition entails that the future power system evolves into a complex cyber-physical energy system (CPES) with strong interactions between the power, communication and neighboring energy systems. Current power system security assessment methods are based on centralized computation...... and N-1 contingencies, while these risks should still be considered in the future CPES, additional factors are affecting the system security. This paper serves as a review of the challenges entailed by transforming the power system into a CPES from a security assessment perspective. It gives...

  12. Parenting Practices and Children's Physical Activity: An Integrative Review.

    Science.gov (United States)

    Hutchens, Amy; Lee, Rebecca E

    2018-02-01

    The purpose of this integrative review was to analyze the state of science concerning the influence of parenting practices on children's physical activity (PA) levels. A total of 38 studies met the inclusion criteria after full-text review. The body of research is limited in experimental designs with only three studies measuring the influence of the intervention on parenting practices. Seven of the 30 quantitative studies (23.3%) found significant associations between parental role modeling of PA and children's PA levels. Seven of the eight (87.5%) qualitative studies identified parental role modeling of PA as important in promoting children's PA. Sixteen of the 30 (53.3%) quantitative studies found that parental support of PA was significantly associated with children's PA. Five of the eight (62.5%) qualitative studies identified logistic support as supporting PA in children. The science could be expanded by the development of randomized controlled trials aimed at this area.

  13. The Copper concentration variation to physical properties of high copper amalgam alloy

    Directory of Open Access Journals (Sweden)

    Aminatun Aminatun

    2006-09-01

    Full Text Available The function of copper (Cu inside amalgam is to increase hardness and impact force and to decrease thermal expansion coefficient. In general, amalgam which is used in dentistry and available in the market is contain Cu 22%, while the maximum Cu concentration is 30%. It is necessary to determine the concentration Cu does generate the best physical properties to be used as dental restorative agent. Amalgam is made by mixing blended-metal Ag-Sn-Cu (with Cu concentration of 13%, 21%, 22%, and 29% and Hg, stirred manually in a bowl for 15 minutes,leave it in temperature 27°C for 24 hours to become hardened. The result of X-Ray Diffractometer (XRD, analyzed by Rietveld method and Rietica program, shows amalgam with Cu 29% concentration for Cu3Sn compound density is 31.790 sma/Å3, for Ag2Hg3 compound is 41.733 sma/ Å3, a Cu3Sn relative weight percentage of 43.23%, Ag2Hg3 of 54.54%, Cu 7Hg6 of 2.23% and hardness of Cu 29% is 90.700 ± 0.005 kgf/mm2. These numbers are the highest values on Cu 29% concentrations compared to other copper concentration variants. Whereas amalgam thermal expansion coefficient on Cu 29% is (2.17 ± 0.9110-3 mm/°C is the lowest value compared to other Cu concentration. The conclution is that adding Cu concentration into amalgam will increase density value, Cu3Sn relative weight percentage, hardness level and will decrease amalgam thermal expansion coefficient. Amalgam 29% Cu concentration has better physical properties compared to amalgam Cu 22% concentration.

  14. A scoping review on smart mobile devices and physical strain.

    Science.gov (United States)

    Tegtmeier, Patricia

    2018-01-01

    Smart mobile devices gain increasing importance at work. Integrating these smart mobile devices into the workplace creates new opportunities and challenges for occupational health and safety. Therefore the aim of the following scoping review was to identify ergonomic challenges with the use of smart mobile devices at work with respect to physical problems. A review of 36 papers based on literature including January 2016 was conducted. Biomechanical measures in the reviewed studies demonstrated i.e., head flexion angles exceeding 20° in 20 out of 26 different conditions described. Furthermore, laterally deviated wrists were frequently noted and thumb and finger flexor muscle activities generally greater than 5% MVC were reported. The reviewed literature indicated an elevated biomechanical risk, especially for the neck, the wrists and thumb. This was due to poor posture, ongoing and intermitted muscle tension, and/or repetitive movements. Papers addressing specific risks for smartphone and tablet use in different work environments are scarce. As the technology, as well as the use of smart mobile devices is rapidly changing, further research, especially for prolonged periods in the workplace is needed.

  15. Noble metal alloys for metal-ceramic restorations.

    Science.gov (United States)

    Anusavice, K J

    1985-10-01

    A review of the comparative characteristics and properties of noble metal alloys used for metal-ceramic restorations has been presented. Selection of an alloy for one's practice should be based on long-term clinical data, physical properties, esthetic potential, and laboratory data on metal-ceramic bond strength and thermal compatibility with commercial dental porcelains. Although gold-based alloys, such as the Au-Pt-Pd, Au-Pd-Ag, and Au-Pd classes, may appear to be costly compared with the palladium-based alloys, they have clearly established their clinical integrity and acceptability over an extended period of time. Other than the relatively low sag resistance of the high gold-low silver content alloys and the potential thermal incompatibility with some commercial porcelain products, few clinical failures have been observed. The palladium-based alloys are less costly than the gold-based alloys. Palladium-silver alloys require extra precautions to minimize porcelain discoloration. Palladium-copper and palladium-cobalt alloys may also cause porcelain discoloration, as copper and cobalt are used as colorants in glasses. The palladium-cobalt alloys are least susceptible to high-temperature creep compared with all classes of noble metals. Nevertheless, insufficient clinical data exist to advocate the general use of the palladium-copper and palladium-cobalt alloys at the present time. One should base the selection and use of these alloys in part on their ability to meet the requirements of the ADA Acceptance Program. A list of acceptable or provisionally acceptable alloys is available from the American Dental Association and is published annually in the Journal of the American Dental Association. Dentists have the legal and ethical responsibility for selection of alloys used for cast restorations. This responsibility should not be delegated to the dental laboratory technician. It is advisable to discuss the criteria for selection of an alloy with the technician and the

  16. Solid-state reactions during mechanical alloying of ternary Fe–Al–X (X=Ni, Mn, Cu, Ti, Cr, B, Si) systems: A review

    Energy Technology Data Exchange (ETDEWEB)

    Hadef, Fatma, E-mail: hadef77@yahoo.fr [Laboratoire de Recherche sur la Physico-Chimie des Surfaces et Interfaces, LRPCSI, Université 20 Août 1955, BP 26, Route d’El-Haddaiek, Skikda 21000 (Algeria); Département de Physique, Faculté des Sciences, Université 20 Août 1955, BP 26, Route d’El-Haddaiek, Skikda 21000 (Algeria)

    2016-12-01

    The last decade has witnessed an intensive research in the field of nanocrystalline materials due to their enhanced properties. A lot of processing techniques were developed in order to synthesis these novel materials, among them mechanical alloying or high-energy ball milling. In fact, mechanical alloying is one of the most common operations in the processing of solids. It can be used to quickly and easily synthesize a variety of technologically useful materials which are very difficult to manufacture by other techniques. One advantage of MA over many other techniques is that is a solid state technique and consequently problems associated with melting and solidification are bypassed. Special attention is being paid to the synthesis of alloys through reactions mainly occurring in solid state in many metallic ternary Fe–Al–X systems, in order to improve mainly Fe–Al structural and mechanical properties. The results show that nanocrystallization is the common result occurring in all systems during MA process. The aim of this work is to illustrate the uniqueness of MA process to induce phase transformation in metallic Fe–Al–X (X=Ni, Mn, Cu, Ti, Cr, B, Si) systems. - Highlights: • A review of state of the art on binary Fe–Al alloys was presented. • Structural and microstructural properties of MA ternary Fe–Al–X alloys were summerized. • MA process is a powerful tool for producing metallic alloys at the nanometer scale.

  17. Recommendations for physical therapists on the treatment of lumbopelvic pain during pregnancy: a systematic review.

    NARCIS (Netherlands)

    van Benten, E.; Pool, J.J.; Mens, J; Pool-Goudzwaard, A.L.

    2014-01-01

    STUDY DESIGN: Systematic review of the literature. OBJECTIVES: To review and assess the peer-reviewed literature on the effectiveness of physical therapy interventions in treating lumbopelvic pain during pregnancy. BACKGROUND: Current guidelines on interventions for lumbopelvic pain during pregnancy

  18. Machinability of Titanium Alloys

    Science.gov (United States)

    Rahman, Mustafizur; Wong, Yoke San; Zareena, A. Rahmath

    Titanium and its alloys find wide application in many industries because of their excellent and unique combination of high strength-to-weight ratio and high resistance to corrosion. The machinability of titanium and its alloys is impaired by its high chemical reactivity, low modulus of elasticity and low thermal conductivity. A number of literatures on machining of titanium alloys with conventional tools and advanced cutting tool materials is reviewed. The results obtained from the study on high speed machining of Ti-6Al-4V alloys with cubic boron nitride (CBN), binderless cubic boron nitride (BCBN) and polycrystalline diamond (PCD) are also summarized.

  19. Physical properties and microstructure study of stainless steel 316L alloy fabricated by selective laser melting

    Science.gov (United States)

    Islam, Nurul Kamariah Md Saiful; Harun, Wan Sharuzi Wan; Ghani, Saiful Anwar Che; Omar, Mohd Asnawi; Ramli, Mohd Hazlen; Ismail, Muhammad Hussain

    2017-12-01

    Selective Laser Melting (SLM) demonstrates the 21st century's manufacturing infrastructure in which powdered raw material is melted by a high energy focused laser, and built up layer-by-layer until it forms three-dimensional metal parts. SLM process involves a variation of process parameters which affects the final material properties. 316L stainless steel compacts through the manipulation of building orientation and powder layer thickness parameters were manufactured by SLM. The effect of the manipulated parameters on the relative density and dimensional accuracy of the 316L stainless steel compacts, which were in the as-build condition, were experimented and analysed. The relationship between the microstructures and the physical properties of fabricated 316L stainless steel compacts was investigated in this study. The results revealed that 90° building orientation has higher relative density and dimensional accuracy than 0° building orientation. Building orientation was found to give more significant effect in terms of dimensional accuracy, and relative density of SLM compacts compare to build layer thickness. Nevertheless, the existence of large number and sizes of pores greatly influences the low performances of the density.

  20. Analysis of evidence for an irreproducible martensite-like behavior in actinide metals and alloys below room temperature. [Review

    Energy Technology Data Exchange (ETDEWEB)

    Sandenaw, T.A.

    1976-05-01

    Evidence is presented which suggests that a low-temperature, martensite-like behavior may be quite general in actinide metals and their alloys and compounds. There may be no metastable martensitic embryos in an ..cap alpha..-phase structure of high-purity U, Np, and Pu formed by a diffusion-controlled ..beta.. ..-->.. ..cap alpha.. transformation, and thus no evidence for low-temperature phases. The effect of impurity content on observed low-temperature physical properties of these actinides is noted. It is proposed that impurities may be playing several roles. They may permit an electron redistribution in dilute alloys dependent upon the length of holding time. Experimentally determined values for the electronic contribution to heat capacity and the density of states of U, Np, and Pu should thus vary over a considerable range, as has been observed. Variations in interstitial ordering of impurity atoms with processing may yield stacking variants of each basic close-packed actinide metal structure and thus determine the number and structure of low-temperature phase. 46 references.

  1. BOOK REVIEW: Physics for Scientists and Engineers Third Edition

    Science.gov (United States)

    Giancoli, Douglas C.

    2000-09-01

    There are a large number of textbooks for the college and university student produced in the USA and here is one that I had not seen before even though it is now in the third edition. But it is so similar to many others. The standard version as reviewed here covers the usual topics of classical physics, namely kinematics, energy, waves and oscillations, thermodynamics, electricity and magnetism and light. Also, as is usual with the American coverage, it includes fluids, special relativity and a short chapter on quantum theory and the atom. An extended version is available covering modern physics, astrophysics and cosmology. There is also available back-up material such as instructor's manual, CD-ROM, video and other extra teaching material Full colour is used and the book is lavishly illustrated with diagrams and photographs. Calculus is used throughout the book, although this is limited to basic differentiation and integration. There is an extensive range of worked examples plus end-of-chapter questions and problems, with numerical answers given to the odd-numbered problems. The physics is illustrated with many everyday examples. The styles of course presentation and hence the styles of book used in the USA and the UK seem to be diverging. It is unlikely such a book as this would be used at A-level. This is not only because of the calculus, albeit simple, but because of the detailed coverage of classical topics. Increasingly there has been a trend in this country to be more selective in content, and yet at the same time to incorporate more modern topics such as solids, environmental and atmospheric physics, particle physics and cosmology, but described in a fairly elementary way. The book would be suitable for preliminary year and first-year university physics courses but its size and weight are daunting. I am not sure why physics described in such an encyclopaedic way is popular in the US but less so here. However, of its type this book is both attractive and

  2. Catalyst Alloys Processing

    Science.gov (United States)

    Tan, Xincai

    2014-10-01

    Catalysts are one of the key materials used for diamond formation at high pressures. Several such catalyst products have been developed and applied in China and around the world. The catalyst alloy most widely used in China is Ni70Mn25Co5 developed at Changsha Research Institute of Mining and Metallurgy. In this article, detailed techniques for manufacturing such a typical catalyst alloy will be reviewed. The characteristics of the alloy will be described. Detailed processing of the alloy will be presented, including remelting and casting, hot rolling, annealing, surface treatment, cold rolling, blanking, finishing, packaging, and waste treatment. An example use of the catalyst alloy will also be given. Industrial experience shows that for the catalyst alloy products, a vacuum induction remelt furnace can be used for remelting, a metal mold can be used for casting, hot and cold rolling can be used for forming, and acid pickling can be used for metal surface cleaning.

  3. Physical properties of Pd and Al transition metals and Pd-Al binary metal alloy investigated by using molecular dynamics simulation

    International Nuclear Information System (INIS)

    Coruh, A.; Uludogan, M.; Tomak, M.; Cagin, T.

    2002-01-01

    In this study, physical properties, such as Pair Distribution Function g(r), Structure Factor S(k)''1'',''4, Diffusion Coefficient D''2''.''4, Intermediate Scattering function S(k,t)''3'',''4 and Dynamical Structure Factor S(k,w)''3'',''4 of some transition metals and metal alloys are investigated by using molecular dynamics simulation method. The simulation is specified for Pd, Al transition metals and Pd-Al binary metal alloys in the liquid form for different concentrations and at various temperatures by using Quantum Sutton-Chen (Q-SC) inter atomic potential. Intermediate scattering function and dynamical structure factor are calculated for various values of wave vector k. Results are in good agreement with published data''1'',''3'',''4

  4. Solute hydrogen and hydride phase implications on the plasticity of zirconium and titanium alloys: a review and some recent advances.

    Science.gov (United States)

    Conforto, E; Guillot, I; Feaugas, X

    2017-07-28

    In this contribution, we propose a review of the possible implications of hydrogen on mechanical behaviour of Zr and Ti alloys with emphasis on the mechanisms of plasticity and strain hardening. Recent advances on the impact of oxygen and hydrogen on the activation volume show that oxygen content hinders creep but hydrogen partially screens this effect. Both aspects are discussed in terms of a locking-unlocking model of the screw dislocation mobility in prismatic slip. Additionally, possible extension of this behaviour is suggested for the [Formula: see text] pyramidal slip. The low hydrogen solubility in both Zr and Ti leads in many cases to hydride precipitation. The nature of these phases depends on the hydrogen content and can show crystallographic orientation relationships with the hexagonal compact structure of the alloys. Some advances on the thermal stability of these phases are illustrated and discussed in relation with the deepening of the misfit dislocations. Under tensile loading, we showed that hydrides enhance the hardening process in relation with internal stress due to strain incompatibilities between the Zr and Ti matrix and hydride phases. Different plastic yielding processes of hydrides were identified, which progressively reduce these strain incompatibilities.This article is part of the themed issue 'The challenges of hydrogen and metals'. © 2017 The Author(s).

  5. The home physical environment and its relationship with physical activity and sedentary behavior: a systematic review.

    Science.gov (United States)

    Kaushal, Navin; Rhodes, Ryan E

    2014-10-01

    Reviews of neighborhood (macro) environment characteristics such as the presence of sidewalks and esthetics have shown significant correlations with resident physical activity (PA) and sedentary (SD) behavior. Currently, no comprehensive review has appraised and collected available evidence on the home (micro) physical environment. The purpose of this review was to examine how the home physical environment relates to adult and child PA and SD behaviors. Articles were searched during May 2014 using Medline, PsycINFO, PubMed, Scopus, and SPORTDiscus databases which yielded 3265 potential studies. Papers were considered eligible if they investigated the presence of PA (ie. exercise equipment, exergaming devices) or SD (ie. television, videogames) equipment and PA or SD behavior. After, screening and manual cross-referencing, 49 studies (20 experimental and 29 observational designs) were found to meet the eligibility criteria. Interventions that reduced sedentary time by using TV limiting devices were shown to be effective for children but the results were limited for adults. Overall, large exercise equipment (ie. treadmills), and prominent exergaming materials (exergaming bike, dance mats) were found to be more effective than smaller devices. Observational studies revealed that location and quantity of televisions correlated with SD behavior with the latter having a greater effect on girls. This was similarly found for the quantity of PA equipment which also correlated with behavior in females. Given the large market for exercise equipment, videos and exergaming, the limited work performed on its effectiveness in homes is alarming. Future research should focus on developing stronger randomized controlled trials, investigate the location of PA equipment, and examine mediators of the gender discrepancy found in contemporary studies. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. Physico-mechanical properties and prosthodontic applications of Co-Cr dental alloys: a review of the literature

    OpenAIRE

    Al Jabbari, Youssef S.

    2014-01-01

    Cobalt-Chromium (Co-Cr) alloys are classified as predominantly base-metal alloys and are widely known for their biomedical applications in the orthopedic and dental fields. In dentistry, Co-Cr alloys are commonly used for the fabrication of metallic frameworks of removable partial dentures and recently have been used as metallic substructures for the fabrication of porcelain-fused-to-metal restorations and implant frameworks. The increased worldwide interest in utilizing Co-Cr alloys for dent...

  7. Stages of change toward physical activity: a review of literature

    Directory of Open Access Journals (Sweden)

    Marlos Rodrigues Domingues

    2008-06-01

    Full Text Available The aim of the present study was to carry out a review of the literature about studies that investigated the stages of change for physical activity among adults. The search was conducted in the following electronic databases: Medline/Pubmed, Web of Science, Ovid, Biomed Central, Elsevier, Oxford, Sports Discus, PsycInfo e Lilacs. The terms used were: “transtheoretical model”, “stages of change”, “stages of readiness” combined with “physical activity” or “exercise”; when appropriated, the equivalent terms in Portuguese were used. Only original or reviews articles were selected, and other type of works were excluded. The issues discussed in this article addressed the background and the temporal evolution of the stages of change, ways of operationalize and analyze the stages, validity and reliability of the instruments applied to measure the stages, and the factors associated with the stages. In conclusion, the importance of the stages of change model to promote physical activity practice was highlighted. ResumoO objetivo do presente estudo foi realizar uma revisão da literatura acerca dos estudos que investigaram os estágios de mudança de comportamento para a prática de atividades físicas em adultos. Para isto, foi efetuada uma pesquisa nas seguintes bases de dados eletrônicas: Medline/Pubmed, Web of Science, Ovid, Biomed Central, Elsevier, Oxford, Sports Discus, PsycInfo e Lilacs. Os descritores utilizados foram: “transtheoretical model”, “stages of change”, “stages of readiness” combinados com “physical activity” ou “exercise”. Quando apropriado, empregaram-se seus termos correspondentes em português. Foram selecionados apenas artigos originais ou de revisão que tratassem sobre o assunto, sendo excluídos outros tipos de trabalhos. Os pontos discutidos neste artigo abordam os tópicos a seguir: origem e evolução dos estágios; formas de operacionalização e de análise dos estágios; validade e

  8. Bringing the Physical Review into the Digital Age

    Science.gov (United States)

    Doyle, Mark

    2013-03-01

    Efforts to make the entire contents of the Physical Review available digitally began early in the 1990's and closely tracked the development of the World Wide Web itself. Not satisfied with just publishing electronic versions of newly published material, the APS also embarked on one of the first systematic digitizations of the entire contents of a major series of journals in any discipline. While all APS journals were online by 1997 and the backfile archive was completed in early 2002, the journals have continued to grow and adapt as the digital environment has matured. This talk will give an account of the evolution of APS journals through the digital transition, from boxes of backup tapes to the full-fledged, invaluable online resource it is today.

  9. A Systematic Review of Physical Activity Interventions in Hispanic Adults

    International Nuclear Information System (INIS)

    Ickes, M.J.; Sharma, M.; Sharma, M.

    2012-01-01

    Healthy People 2020 aims to achieve health equity, eliminate disparities, and improve the health of all groups. Regular physical activity (PA) improves overall health and fitness and has the capability to reduce risk for chronic diseases. Identifying barriers which relate to the Hispanic population is important when designing PA interventions. Therefore, the purpose was to review existing PA interventions targeting Hispanic adults published between 1988 and 2011. This paper was limited to interventions which included more than 35% Hispanic adults (n=20). Most of the interventions were community based (n=16), although clinical, family-based, and faith-based settings were also represented. Interventions incorporated theory (n=16), with social cognitive theory and trans theoretical model being used most frequently. Social support was integral, building on the assumption that it is a strong motivator of PA. Each of the interventions reported success related to PA, social support, and/or BMI. Lessons learned should be incorporated into future interventions.

  10. Biological and Physical Space Research Laboratory 2002 Science Review

    Science.gov (United States)

    Curreri, P. A. (Editor); Robinson, M. B. (Editor); Murphy, K. L. (Editor)

    2003-01-01

    With the International Space Station Program approaching core complete, our NASA Headquarters sponsor, the new Code U Enterprise, Biological and Physical Research, is shifting its research emphasis from purely fundamental microgravity and biological sciences to strategic research aimed at enabling human missions beyond Earth orbit. Although we anticipate supporting microgravity research on the ISS for some time to come, our laboratory has been vigorously engaged in developing these new strategic research areas.This Technical Memorandum documents the internal science research at our laboratory as presented in a review to Dr. Ann Whitaker, MSFC Science Director, in July 2002. These presentations have been revised and updated as appropriate for this report. It provides a snapshot of the internal science capability of our laboratory as an aid to other NASA organizations and the external scientific community.

  11. The role of angiogenesis in implant dentistry part I: Review of titanium alloys, surface characteristics and treatments.

    Science.gov (United States)

    Saghiri, M-A; Asatourian, A; Garcia-Godoy, F; Sheibani, N

    2016-07-01

    Angiogenesis plays an important role in osseointegration process by contributing to inflammatory and regenerative phases of surrounding alveolar bone. The present review evaluated the effect of titanium alloys and their surface characteristics including: surface topography (macro, micro, and nano), surface wettability/energy, surface hydrophilicity or hydrophobicity, surface charge, and surface treatments of dental implants on angiogenesis events, which occur during osseointegration period. An electronic search was performed in PubMed, MEDLINE, and EMBASE databases via OVID using the keywords mentioned in the PubMed and MeSH headings regarding the role of angiogenesis in implant dentistry from January 2000-April 2014. Of the 2,691 articles identified in our initial search results, only 30 met the inclusion criteria set for this review. The hydrophilicity and topography of dental implants are the most important and effective surface characteristics in angiogenesis and osteogenesis processes. The surface treatments or modifications of dental implants are mainly directed through the enhancement of biological activity and functionalization in order to promote osteogenesis and angiogenesis, and accelerate the osseointegration procedure. Angiogenesis is of great importance in implant dentistry in a manner that most of the surface characteristics and treatments of dental implants are directed toward creating a more pro-angiogenic surface on dental implants. A number of studies discussed the effect of titanium alloys, dental implant surface characteristic and treatments on agiogenesis process. However, clinical trials and in-vivo studies delineating the mechanisms of dental implants, and their surface characteristics or treatments, action in angiogenesis processes are lagging.

  12. Quality Management and Control of Low Pressure Cast Aluminum Alloy

    Science.gov (United States)

    Zhang, Dianxi; Zhang, Yanbo; Yang, Xiufan; Chen, Zhaosong; Jiang, Zelan

    2018-01-01

    This paper briefly reviews the history of low pressure casting and summarizes the major production processes of low pressure casting. It briefly introduces the quality management and control of low pressure cast aluminum alloy. The main processes include are: preparation of raw materials, Melting, refining, physical and chemical analysis, K-mode inspection, sand core, mold, heat treatment and so on.

  13. Physical examination prior to initiating hormonal contraception: a systematic review.

    Science.gov (United States)

    Tepper, Naomi K; Curtis, Kathryn M; Steenland, Maria W; Marchbanks, Polly A

    2013-05-01

    Provision of contraception is often linked with physical examination, including clinical breast examination (CBE) and pelvic examination. This review was conducted to evaluate the evidence regarding outcomes among women with and without physical examination prior to initiating hormonal contraceptives. The PubMed database was searched from database inception through March 2012 for all peer-reviewed articles in any language concerning CBE and pelvic examination prior to initiating hormonal contraceptives. The quality of each study was assessed using the United States Preventive Services Task Force grading system. The search did not identify any evidence regarding outcomes among women screened versus not screened with CBE prior to initiation of hormonal contraceptives. The search identified two case-control studies of fair quality which compared women who did or did not undergo pelvic examination prior to initiating oral contraceptives (OCs) or depot medroxyprogesterone acetate (DMPA). No differences in risk factors for cervical neoplasia, incidence of sexually transmitted infections, incidence of abnormal Pap smears or incidence of abnormal wet mount findings were observed. Although women with breast cancer should not use hormonal contraceptives, there is little utility in screening prior to initiation, due to the low incidence of breast cancer and uncertain value of CBE among women of reproductive age. Two fair quality studies demonstrated no differences between women who did or did not undergo pelvic examination prior to initiating OCs or DMPA with respect to risk factors or clinical outcomes. In addition, pelvic examination is not likely to detect any conditions for which hormonal contraceptives would be unsafe. Published by Elsevier Inc.

  14. Key improvements in machining of Ti6al4v alloy: A review

    Science.gov (United States)

    Katta, Sivakoteswararao; Chaitanya, G.

    2017-07-01

    Now a days the use of ti-6al-4v alloy is high in demand in many industries like aero space, bio medical automobile, space, military etc. the production rates in the industries are not sufficient because the machiniability of ti-6al-4v is the main problem, there are several cutting tools available for metal cutting operations still there is a gap in finding the proper cutting tool material for machining of ti-6al-4v. because the properties of titanium like high heat resistant, low thermal conductivity, low weight ratio, less corrosiveness, and more many properties attracting the industrialists to use titanium as their material for their products, many researchers done the research on machininbility of ti-6al-4v by using different tool materials. but as for my literature survey there is still lot of scope is available, to find better cutting tool with techniques for machining ti-6al-4v. in this paper iam discussing the work done by various researchers on ti-6al-4v alloy with different techniques.

  15. REVIEW: Fifty years of Monte Carlo simulations for medical physics

    Science.gov (United States)

    Rogers, D. W. O.

    2006-07-01

    Monte Carlo techniques have become ubiquitous in medical physics over the last 50 years with a doubling of papers on the subject every 5 years between the first PMB paper in 1967 and 2000 when the numbers levelled off. While recognizing the many other roles that Monte Carlo techniques have played in medical physics, this review emphasizes techniques for electron-photon transport simulations. The broad range of codes available is mentioned but there is special emphasis on the EGS4/EGSnrc code system which the author has helped develop for 25 years. The importance of the 1987 Erice Summer School on Monte Carlo techniques is highlighted. As an illustrative example of the role Monte Carlo techniques have played, the history of the correction for wall attenuation and scatter in an ion chamber is presented as it demonstrates the interplay between a specific problem and the development of tools to solve the problem which in turn leads to applications in other areas. This paper is dedicated to W Ralph Nelson and to the memory of Martin J Berger, two men who have left indelible marks on the field of Monte Carlo simulation of electron-photon transport.

  16. Implementation of school based physical activity interventions: a systematic review.

    Science.gov (United States)

    Naylor, Patti-Jean; Nettlefold, Lindsay; Race, Douglas; Hoy, Christa; Ashe, Maureen C; Wharf Higgins, Joan; McKay, Heather A

    2015-03-01

    Implementation science is an emerging area in physical activity (PA) research. We sought to establish the current state of the evidence related to implementation of school-based PA models to explore 1) the relationship between implementation and health outcomes, and 2) factors that influence implementation. We searched 7 electronic databases (1995-2014) and included controlled studies of school-based PA programmes for healthy youth (6-18 y) measuring at least one physical health-related outcome. For objective 1, studies linked implementation level to student-level health outcome(s). For objective 2, studies reported factors associated with implementation. There was substantial variability in how health outcomes and implementation were assessed. Few studies linked implementation and health outcomes (n=15 interventions). Most (11/15) reported a positive relationship between implementation and at least one health outcome. Implementation factors were reported in 29 interventions. Of 22 unique categories, time was the most prevalent influencing factor followed by resource availability/quality and supportive school climate. Implementation evaluation supports scale-up of effective school-based PA interventions and thus population-level change. Our review serves as a call to action to 1) address the link between implementation and outcome within the school-based PA literature and 2) improve and standardize definitions and measurement of implementation. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. 77 FR 14441 - Proposal Review Panel for Physics; Notice of Meeting

    Science.gov (United States)

    2012-03-09

    ... NATIONAL SCIENCE FOUNDATION Proposal Review Panel for Physics; Notice of Meeting In accordance... announces the following meeting. Name: LIGO Annual Review Site Visit at Hanford Observatory for Physics...: Partially Closed. Contact Person: Thomas Carruthers, Program Director, Division of Physics, National Science...

  18. 76 FR 66998 - Proposal Review Panel for Physics; Notice of Meeting

    Science.gov (United States)

    2011-10-28

    ... Proposal Review Panel for Physics; Notice of Meeting In accordance with the Federal Advisory Committee Act...: LIGO Annual Review Site Visit at Hanford Observatory for Physics (1208). Date and Time: Wednesday...: Thomas Carruthers, Program Director, Division of Physics, National Science Foundation, (703) 292-7373...

  19. On the recovery of the physical and mechanical properties of a CuCrZr alloy subjected to heat treatments simulating the thermal cycle of hot isostatic pressing

    International Nuclear Information System (INIS)

    Holzwarth, U.; Pisoni, M.; Scholz, R.; Stamm, H.; Volcan, A.

    2000-01-01

    Due to their high mechanical strength and thermal conductivity precipitation hardened CuCrZr alloys are being considered as potential heat sink material for the ITER divertor vertical target. The fabrication of the divertor component involves a joining procedure by hot isostatic pressing (HIP). The impact of this method on the degradation of the physical and mechanical properties of the CuCrZr alloy and their possible subsequent recovery by (re-)aging heat treatments have been investigated by hardness measurements, tensile testing and measurements of thermal diffusivity and electrical resistivity. The thermal cycle of hot isostatic pressing has been simulated by solution annealing finished by cooling rates between 0.03 and 1.5 K s -1 . The experiments revealed that a successful recovery of the desired mechanical strength is only achievable if cooling rates of about 1 K s -1 or higher can be realized after HIP. Otherwise the alloy becomes already over-aged during slow cooling after the joining procedure

  20. Final report on characterization of physical and mechanical properties of copper and copper alloys before and after irradiation. (ITER R and D Task no. T213)

    Energy Technology Data Exchange (ETDEWEB)

    Singh, B.N.; Taehtinen, S. [VTT Manufacturing Technology (Finland)

    2001-12-01

    The present report summarizes and highlights the main results of the work carried out during the last 5 - 6 years on effects of neutron irradiation on physical and mechanical properties of copper and copper alloys. The work was an European contribution to ITER Research and Development programme and was carried out by the Associations Euratom - Risoe and Euratom - Tekes. Details of the investigations carried out within the framework of the present task and the main results have been reported in various reports and journal publication. On the basis of these results some conclusions are drawn regarding the suitability of a copper alloy for its use in the first wall and divertor components of ITER. It is pointed out that the present work has managed only to identify some of the critical problems and limitations of the copper alloys for their employment in the hostile environment of 14 MeV neutrons. A considerable amount of further effort is needed to find a realistic and optimum solution. (au)

  1. Meaningful Experiences in Physical Education and Youth Sport: A Review of the Literature

    Science.gov (United States)

    Beni, Stephanie; Fletcher, Tim; Ní Chróinín, Déirdre

    2017-01-01

    The purpose of this research is to review the literature about young people's meaningful experiences in physical education and youth sport. We reviewed 50 empirical peer-reviewed articles published in English since 1987. Five themes were identified as central influences to young people's meaningful experiences in physical education and sport:…

  2. PHYSICS

    CERN Multimedia

    P. Sphicas

    There have been three physics meetings since the last CMS week: “physics days” on March 27-29, the Physics/ Trigger week on April 23-27 and the most recent physics days on May 22-24. The main purpose of the March physics days was to finalize the list of “2007 analyses”, i.e. the few topics that the physics groups will concentrate on for the rest of this calendar year. The idea is to carry out a full physics exercise, with CMSSW, for select physics channels which test key features of the physics objects, or represent potential “day 1” physics topics that need to be addressed in advance. The list of these analyses was indeed completed and presented in the plenary meetings. As always, a significant amount of time was also spent in reviewing the status of the physics objects (reconstruction) as well as their usage in the High-Level Trigger (HLT). The major event of the past three months was the first “Physics/Trigger week” in Apri...

  3. Selective Laser Melting Technique of Co-Cr Dental Alloys: A Review of Structure and Properties and Comparative Analysis with Other Available Techniques.

    Science.gov (United States)

    Koutsoukis, Theodoros; Zinelis, Spiros; Eliades, George; Al-Wazzan, Khalid; Rifaiy, Mohammed Al; Al Jabbari, Youssef S

    2015-06-01

    The aim of this study was to review the effect of selective laser melting (SLM) procedure on the properties of dental structures made of Co-Cr alloys and to evaluate its quality and compare it to those produced by conventional casting and milling fabrication techniques. A computerized database search using PubMed and Scopus was conducted for peer-reviewed scientific research studies regarding the use of SLM in Co-Cr dental alloys with no restrictions for publication years. The search engines provided hundreds of results, and only 48 scientific research papers, case studies, or literature reviews were considered relevant for this review. The innovative manufacturing concept of SLM offers many advantages compared with casting and milling fabrication techniques. SLM provides different microstructure from casting and milling with minimal internal porosity and internal fitting, marginal adaptation, and comparable bond strength to porcelain. Mechanical and electrochemical properties of SLM structures are enhanced compared to cast, while clinical longevity of single-metal ceramic crowns is comparable to Au-Pt dental alloy. The SLM technique provides dental prosthetic restorations more quickly and less expensively without compromising their quality compared with restorations prepared by casting and milling techniques. The current SLM devices provide metallic restorations made of Co-Cr alloys for removable and fixed partial dentures without compromising the alloy or restoration properties at a fraction of the time and cost, showing great potential to replace the aforementioned fabrication techniques in the long term; however, further clinical studies are essential to increase the acceptance of this technology by the worldwide dental community. © 2015 by the American College of Prosthodontists.

  4. Physics Division annual review, April 1, 1991--March 31, 1992

    International Nuclear Information System (INIS)

    Henning, W.F.

    1992-08-01

    This report contains brief discusses on topics in the following areas: Research at atlas; operation and development of atlas; medium-energy nuclear physics and weak interactions; theoretical nuclear physics; and atomic and molecular physics research

  5. Physics Division annual review, April 1, 1991--March 31, 1992

    Energy Technology Data Exchange (ETDEWEB)

    Henning, W.F.

    1992-08-01

    This report contains brief discusses on topics in the following areas: Research at atlas; operation and development of atlas; medium-energy nuclear physics and weak interactions; theoretical nuclear physics; and atomic and molecular physics research.

  6. Physics Division annual review, April 1, 1989--March 31, 1990

    International Nuclear Information System (INIS)

    1990-07-01

    This report contains papers in the following research areas: research at atlas; operation and development of atlas; medium-energy nuclear physics and weak interactions; theoretical nuclear physics; and atomic and molecular physics research

  7. Physics Division annual review, April 1, 1990--March 31, 1991

    International Nuclear Information System (INIS)

    1991-06-01

    This report discusses: Research At Atlas; Operation and Development of Atlas; Medium-Energy Nuclear Physics and Weak Interactions; Theoretical Nuclear Physics; High-Resolution Laser-rf Spectroscopy with Beams of Atoms and Molecules; Fast Ion-Beam/Laser Studies of Atomic and Molecular Structure; Interactions of Fast Atomic and Molecular Ions with Solid and Gaseous Targets; Theoretical Atomic Physics; Atomic Physics at Atlas and the ECR Source; Atomic Physics at Synchrotron Light Sources; and Accelerator Facilities for Atomic Physics

  8. The use of gold and gold alloys in prosthetic dentistry – a literature review

    Directory of Open Access Journals (Sweden)

    Oleszek-Listopad Justyna

    2015-09-01

    Full Text Available Gold is a noble metal with very good chemical resistance. It also does not become oxidized in water or air. Pure gold has a bright yellow color and shine, and it is a heavy, but soft metal with huge plasticity and ductility. For many years, gold and its alloys have been recognized as being great prosthetic material in dental practice. In current dentistry, the progress in materials science and galvanoforming techniques have made it possible to create precise restorations utilizing this metal. This pertains both to fixed and removable dentures. Galvanized gold has a range of advantages, among these being biocompatibility, proper marginal tightness, endurance, its esthetic design and the fact that it boasts bacteriostatic features.

  9. The effects of psychological treatments for adult depression on physical activity: A systematic review.

    NARCIS (Netherlands)

    Cuijpers, P.; de Wit, L.M.; Taylor, A.

    2014-01-01

    Objectives Physical activity and depression have been consistently shown to be inversely associated in epidemiological surveys. It is not clear, however, whether successful treatment of depression results in increases in physical activity. Method Systematic review of randomized trials examining

  10. A systematic review of financial incentives for physical activity: The effects on physical activity and related outcomes

    NARCIS (Netherlands)

    Barte, J.C.M.; Wendel-Vos, G.C.W.

    2017-01-01

    The aim of this review is to give an overview of the available evidence on the effects of financial incentives to stimulate physical activity. Therefore, a systematic literature search was performed for randomized trials that investigate the effects of physical-activity-related financial incentives

  11. Increasing Asian International College Students' Physical Activity Behavior: A Review of the Youth Physical Activity Promotion Model

    Science.gov (United States)

    Yan, Zi; Cardinal, Bradley J.

    2013-01-01

    Asian students attending American colleges and universities report relatively low levels of physical activity participation, which may hinder their ability to realize their full human potential (i.e., cognitively, physically, socially). This paper reviewed the possible reasons underlying their generally inactive lifestyle, addressed the importance…

  12. Effects of bonding bakeout thermal cycles on pre- and post irradiation microstructures, physical, and mechanical properties of copper alloys

    Energy Technology Data Exchange (ETDEWEB)

    Singh, B.N.; Eldrup, M.; Toft, P.; Edwards, D.J. [Pacific Northwest National Laboratory, Richland, WA (United States)

    1996-10-01

    At present, dispersion strengthened (DS) copper is being considered as the primary candidate material for the ITER first wall and divertor components. Recently, it was agreed among the ITER parties that a backup alloy should be selected from the two well known precipitation hardened copper alloys, CuCrZr and CuNiBe. It was therefore decided to carry out screening experiments to simulate the effect of bonding and bakeout thermal cycles on microstructure, mechanical properties, and electrical resistivity of CuCrZr and CuNiBe alloys. On the basis of the results of these experiments, one of the two alloys will be selected as a backup material. Tensile specimens of CuCrZr and CuNiBe alloys were given various heat treatments corresponding to solution anneal, prime ageing, and bonding thermal cycle followed by reageing and the reactor bakeout treatment at 623K for 100 hours. Tensile specimens of the DS copper were also given the heat treatment corresponding to the bonding thermal cycle. A number of these heat treated specimens of CuCrZr, CuNiBe, and DS copper were neutron irradiated at 523K to a dose level of {approx}0.3 dpa (NRT) in the DR-3 reactor at Riso. Both unirradiated and irradiated specimens with the various heat treatments were tensile tested at 532K. The dislocation, precipitate and void microstructures and electrical resistivity of these specimens were also determined. Results of these investigations will be reported and discussed in terms of thermal and irradiation stability of precipitates and irradiation-induced precipitation and recovery of dislocation microstructure. Results show that the bonding and bakeout thermal cycles are not likely to have any serious deleterious effects on the performance of these alloys. The CuNiBe alloys were found to be susceptible to radiation-induced embrittlement, however, the exact mechanism is not yet known. It is thought that radiation-induced precipitation and segregation of the beryllium may be responsible.

  13. Small-angle scattering in materials science - a short review of applications in alloys, ceramics and composite materials

    Energy Technology Data Exchange (ETDEWEB)

    Fratzl, P. [Erich-Schmid-Inst. of Materials Science, Austrian Academy of Sciences (Austria); Univ. of Leoben, Leoben (Austria); Materials Center Leoben GmbH and the Ludwig-Boltzmann-Inst. of Osteology, Wien (Austria)

    2003-06-01

    Since the early days of small-angle scattering (SAS), this technique has been used to characterize the structure of solid materials on the nanometer scale. Some recent developments in this field will be reviewed, focusing on alloys, ceramics and (nano-) composite materials. The large field of SAS from polymeric systems will not be covered. Classical applications of SAS are the characterization of pores or precipitates in alloys, for instance. In more recent years, a range of new applications for X-ray SAS has emerged owing to the availability of more and more brilliant (synchrotron) X-ray sources. Examples include grazing-incidence SAXS, used increasingly to characterize nano-structured surfaces on semiconductors and also on other materials. The use of a narrow X-ray beam also allows the investigation of extremely inhomogeneous or hierarchically structured materials by scanning SAXS. In this approach, the specimen is moved step by step across an X-ray beam with a diameter of a few micrometers (or even less), collecting a SAXS pattern at each step. In neutron SAS, the systematic use of magnetic cross-sections has brought considerable progress in the study of magnetic nano-particles or nano-composites. Single crystalline or textured materials are being studied under several orientations with respect to the primary beam to yield three-dimensional (neutron or X-ray) SAS patterns. In many cases, SAS is combined with other techniques, such as electron microscopy, spectroscopy or mechanical characterization, the most elegant being an in-situ combination. A number of recent examples for the above-mentioned approaches will be given. (orig.)

  14. Surface characterization and corrosion behavior of calcium phosphate-base composite layer on titanium and its alloys via plasma electrolytic oxidation: A review paper.

    Science.gov (United States)

    Rafieerad, A R; Ashra, M R; Mahmoodian, R; Bushroa, A R

    2015-12-01

    In recent years, calcium phosphate-base composites, such as hydroxyapatite (HA) and carbonate apatite (CA) have been considered desirable and biocompatible coating layers in clinical and biomedical applications such as implants because of the high resistance of the composites. This review focuses on the effects of voltage, time and electrolytes on a calcium phosphate-base composite layer in case of pure titanium and other biomedical grade titanium alloys via the plasma electrolytic oxidation (PEO) method. Remarkably, these parameters changed the structure, morphology, pH, thickness and crystallinity of the obtained coating for various engineering and biomedical applications. Hence, the structured layer caused improvement of the biocompatibility, corrosion resistance and assignment of extra benefits for Osseo integration. The fabricated layer with a thickness range of 10 to 20 μm was evaluated for physical, chemical, mechanical and tribological characteristics via XRD, FESEM, EDS, EIS and corrosion analysis respectively, to determine the effects of the applied parameters and various electrolytes on morphology and phase transition. Moreover, it was observed that during PEO, the concentration of calcium, phosphor and titanium shifts upward, which leads to an enhanced bioactivity by altering the thickness. The results confirm that the crystallinity, thickness and contents of composite layer can be changed by applying thermal treatments. The corrosion behavior was investigated via the potentiodynamic polarization test in a body-simulated environment. Here, the optimum corrosion resistance was obtained for the coating process condition at 500 V for 15 min in Ringer solution. This review has been summarized, aiming at the further development of PEO by producing more adequate titanium-base implants along with desired mechanical and biomedical features. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Sorption isotherms: A review on physical bases, modeling and measurement

    Energy Technology Data Exchange (ETDEWEB)

    Limousin, G. [Atomic Energy Commission, Tracers Technology Laboratory, 38054 Grenoble Cedex (France) and Laboratoire d' etude des Transferts en Hydrologie et Environnement (CNRS-INPG-IRD-UJF), BP 53, 38041 Grenoble Cedex (France)]. E-mail: guillaumelimousin@yahoo.fr; Gaudet, J.-P. [Laboratoire d' etude des Transferts en Hydrologie et Environnement (CNRS-INPG-IRD-UJF), BP 53, 38041 Grenoble Cedex (France); Charlet, L. [Laboratoire de Geophysique Interne et Techtonophysique - CNRS-IRD-LCPC-UJF-Universite de Savoie, BP 53, 38041 Grenoble Cedex (France); Szenknect, S. [Atomic Energy Commission, Tracers Technology Laboratory, 38054 Grenoble Cedex (France); Barthes, V. [Atomic Energy Commission, Tracers Technology Laboratory, 38054 Grenoble Cedex (France); Krimissa, M. [Electricite de France, Division Recherche et Developpement, Laboratoire National d' Hydraulique et d' Environnement - P78, 6 quai Watier, 78401 Chatou (France)

    2007-02-15

    The retention (or release) of a liquid compound on a solid controls the mobility of many substances in the environment and has been quantified in terms of the 'sorption isotherm'. This paper does not review the different sorption mechanisms. It presents the physical bases underlying the definition of a sorption isotherm, different empirical or mechanistic models, and details several experimental methods to acquire a sorption isotherm. For appropriate measurements and interpretations of isotherm data, this review emphasizes 4 main points: (i) the adsorption (or desorption) isotherm does not provide automatically any information about the reactions involved in the sorption phenomenon. So, mechanistic interpretations must be carefully verified. (ii) Among studies, the range of reaction times is extremely wide and this can lead to misinterpretations regarding the irreversibility of the reaction: a pseudo-hysteresis of the release compared with the retention is often observed. The comparison between the mean characteristic time of the reaction and the mean residence time of the mobile phase in the natural system allows knowing if the studied retention/release phenomenon should be considered as an instantaneous reversible, almost irreversible phenomenon, or if reaction kinetics must be taken into account. (iii) When the concentration of the retained substance is low enough, the composition of the bulk solution remains constant and a single-species isotherm is often sufficient, although it remains strongly dependent on the background medium. At higher concentrations, sorption may be driven by the competition between several species that affect the composition of the bulk solution. (iv) The measurement method has a great influence. Particularly, the background ionic medium, the solid/solution ratio and the use of flow-through or closed reactor are of major importance. The chosen method should balance easy-to-use features and representativity of the studied

  16. Physical activity counseling in medical school education: a systematic review

    Science.gov (United States)

    Dacey, Marie L.; Kennedy, Mary A.; Polak, Rani; Phillips, Edward M.

    2014-01-01

    Background Despite a large evidence base to demonstrate the health benefits of regular physical activity (PA), few physicians incorporate PA counseling into office visits. Inadequate medical training has been cited as a cause for this. This review describes curricular components and assesses the effectiveness of programs that have reported outcomes of PA counseling education in medical schools. Methods The authors systematically searched MEDLINE, EMBASE, PsychINFO, and ERIC databases for articles published in English from 2000 through 2012 that met PICOS inclusion criteria of medical school programs with PA counseling skill development and evaluation of outcomes. An initial search yielded 1944 citations, and 11 studies representing 10 unique programs met criteria for this review. These studies were described and analyzed for study quality. Strength of evidence for six measured outcomes shared by multiple studies was also evaluated, that is, students’ awareness of benefits of PA, change in students’ attitudes toward PA, change in personal PA behaviors, improvements in PA counseling knowledge and skills, self-efficacy to conduct PA counseling, and change in attitude toward PA counseling. Results Considerable heterogeneity of teaching methods, duration, and placement within the curriculum was noted. Weak research designs limited an optimal evaluation of effectiveness, that is, few provided pre-/post-intervention assessments, and/or included control comparisons, or met criteria for intervention transparency and control for risk of bias. The programs with the most evidence of improvement indicated positive changes in students’ attitudes toward PA, their PA counseling knowledge and skills, and their self-efficacy to conduct PA counseling. These programs were most likely to follow previous recommendations to include experiential learning, theoretically based frameworks, and students’ personal PA behaviors. Conclusions Current results provide some support for

  17. Physical activity counseling in medical school education: a systematic review

    Directory of Open Access Journals (Sweden)

    Marie L. Dacey

    2014-07-01

    Full Text Available Background: Despite a large evidence base to demonstrate the health benefits of regular physical activity (PA, few physicians incorporate PA counseling into office visits. Inadequate medical training has been cited as a cause for this. This review describes curricular components and assesses the effectiveness of programs that have reported outcomes of PA counseling education in medical schools. Methods: The authors systematically searched MEDLINE, EMBASE, PsychINFO, and ERIC databases for articles published in English from 2000 through 2012 that met PICOS inclusion criteria of medical school programs with PA counseling skill development and evaluation of outcomes. An initial search yielded 1944 citations, and 11 studies representing 10 unique programs met criteria for this review. These studies were described and analyzed for study quality. Strength of evidence for six measured outcomes shared by multiple studies was also evaluated, that is, students’ awareness of benefits of PA, change in students’ attitudes toward PA, change in personal PA behaviors, improvements in PA counseling knowledge and skills, self-efficacy to conduct PA counseling, and change in attitude toward PA counseling. Results: Considerable heterogeneity of teaching methods, duration, and placement within the curriculum was noted. Weak research designs limited an optimal evaluation of effectiveness, that is, few provided pre-/post-intervention assessments, and/or included control comparisons, or met criteria for intervention transparency and control for risk of bias. The programs with the most evidence of improvement indicated positive changes in students’ attitudes toward PA, their PA counseling knowledge and skills, and their self-efficacy to conduct PA counseling. These programs were most likely to follow previous recommendations to include experiential learning, theoretically based frameworks, and students’ personal PA behaviors. Conclusions: Current results provide

  18. Physical activity counseling in medical school education: a systematic review.

    Science.gov (United States)

    Dacey, Marie L; Kennedy, Mary A; Polak, Rani; Phillips, Edward M

    2014-01-01

    Despite a large evidence base to demonstrate the health benefits of regular physical activity (PA), few physicians incorporate PA counseling into office visits. Inadequate medical training has been cited as a cause for this. This review describes curricular components and assesses the effectiveness of programs that have reported outcomes of PA counseling education in medical schools. The authors systematically searched MEDLINE, EMBASE, PsychINFO, and ERIC databases for articles published in English from 2000 through 2012 that met PICOS inclusion criteria of medical school programs with PA counseling skill development and evaluation of outcomes. An initial search yielded 1944 citations, and 11 studies representing 10 unique programs met criteria for this review. These studies were described and analyzed for study quality. Strength of evidence for six measured outcomes shared by multiple studies was also evaluated, that is, students' awareness of benefits of PA, change in students' attitudes toward PA, change in personal PA behaviors, improvements in PA counseling knowledge and skills, self-efficacy to conduct PA counseling, and change in attitude toward PA counseling. Considerable heterogeneity of teaching methods, duration, and placement within the curriculum was noted. Weak research designs limited an optimal evaluation of effectiveness, that is, few provided pre-/post-intervention assessments, and/or included control comparisons, or met criteria for intervention transparency and control for risk of bias. The programs with the most evidence of improvement indicated positive changes in students' attitudes toward PA, their PA counseling knowledge and skills, and their self-efficacy to conduct PA counseling. These programs were most likely to follow previous recommendations to include experiential learning, theoretically based frameworks, and students' personal PA behaviors. Current results provide some support for previous recommendations, and current initiatives

  19. Physical fitness and academic performance in youth: A systematic review.

    Science.gov (United States)

    Santana, C C A; Azevedo, L B; Cattuzzo, M T; Hill, J O; Andrade, L P; Prado, W L

    2017-06-01

    Physical fitness (PF) is a construct of health- and skill-related attributes which have been associated with academic performance (AP) in youth. This study aimed to review the scientific evidence on the association among components of PF and AP in children and adolescents. A systematic review of articles using databases PubMed/Medline, ERIC, LILACS, SciELO, and Web of Science was undertaken. Cross-sectional and longitudinal studies examining the association between at least one component of PF and AP in children and adolescents, published between 1990 and June 2016, were included. Independent extraction of articles was carried out by the two authors using predefined data fields. From a total of 45 studies included, 25 report a positive association between components of PF with AP and 20 describe a single association between cardiorespiratory fitness (CRF) and AP. According to the Strengthening the Reporting of Observational Studies in Epidemiology guidelines: 12 were classified as low, 32 as medium risk, and 1 as high risk of bias. Thirty-one studies reported a positive association between AP and CRF, six studies with muscular strength, three studies with flexibility, and seven studies reported a positive association between clustered of PF components and AP. The magnitude of the associations is weak to moderate (β = 0.10-0.42 and odds = 1.01-4.14). There is strong evidence for a positive association between CRF and cluster of PF with AP in cross-sectional studies; and evidence from longitudinal studies for a positive association between cluster of PF and AP; the relationship between muscular strength and flexibility with AP remains uncertain. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  20. Alloy materials

    Energy Technology Data Exchange (ETDEWEB)

    Hans Thieme, Cornelis Leo (Westborough, MA); Thompson, Elliott D. (Coventry, RI); Fritzemeier, Leslie G. (Acton, MA); Cameron, Robert D. (Franklin, MA); Siegal, Edward J. (Malden, MA)

    2002-01-01

    An alloy that contains at least two metals and can be used as a substrate for a superconductor is disclosed. The alloy can contain an oxide former. The alloy can have a biaxial or cube texture. The substrate can be used in a multilayer superconductor, which can further include one or more buffer layers disposed between the substrate and the superconductor material. The alloys can be made a by process that involves first rolling the alloy then annealing the alloy. A relatively large volume percentage of the alloy can be formed of grains having a biaxial or cube texture.

  1. Physics Division annual review, April 1, 1988--March 31, 1989

    Energy Technology Data Exchange (ETDEWEB)

    Thayer, K.J. (ed.)

    1989-08-01

    This document discusses the following main topics: Research at Atlas; Operation and Development of Atlas; Medium-Energy Nuclear Physics and Weak Interactions; Theoretical Nuclear Physics; Interactions of Fast Atomic and Molecular Ions with Solid and Gaseous Targets; Atomic Physics at Synchrotron Light Sources; Atomic Physics at Atlas and the ECR Source; Theoretical Atomic Physics; High-Resolution Laser-rf Spectroscopy of Atomic and Molecular Beams; and Fast Ion-Beam/Laser Studies of Atomic and Molecular Structure.

  2. Physics Division annual review, April 1, 1988--March 31, 1989

    International Nuclear Information System (INIS)

    Thayer, K.J.

    1989-08-01

    This document discusses the following main topics: Research at Atlas; Operation and Development of Atlas; Medium-Energy Nuclear Physics and Weak Interactions; Theoretical Nuclear Physics; Interactions of Fast Atomic and Molecular Ions with Solid and Gaseous Targets; Atomic Physics at Synchrotron Light Sources; Atomic Physics at Atlas and the ECR Source; Theoretical Atomic Physics; High-Resolution Laser-rf Spectroscopy of Atomic and Molecular Beams; and Fast Ion-Beam/Laser Studies of Atomic and Molecular Structure

  3. Impact damage resistance and damage suppression properties of shape memory alloys in hybrid composites—a review

    International Nuclear Information System (INIS)

    Angioni, S L; Meo, M; Foreman, A

    2011-01-01

    Composite materials are known to have a poor resistance to through-the-thickness impact loading. There are various methods for improving their impact damage tolerance, such as fiber toughening, matrix toughening, interface toughening, through-the-thickness reinforcements, and selective interlayers and hybrids. Hybrid composites with improved impact resistance are particularly useful in military and commercial civil applications. Hybridizing composites using shape memory alloys (SMA) is one solution since SMA materials can absorb the energy of the impact through superelastic deformation or recovery stress, reducing the effects of the impact on the composite structure. The SMA material may be embedded in the hybrid composites (SMAHC) in many different forms and also the characteristics of the fiber reinforcements may vary, such as SMA wires in woven laminates or SMA foils in unidirectional laminates, only to cite two examples. We will review the state of the art of SMAHC for the purpose of damage suppression. Both the active and passive damage suppression mechanisms will be considered. (topical review)

  4. Precision forging technology for aluminum alloy

    Science.gov (United States)

    Deng, Lei; Wang, Xinyun; Jin, Junsong; Xia, Juchen

    2018-03-01

    Aluminum alloy is a preferred metal material for lightweight part manufacturing in aerospace, automobile, and weapon industries due to its good physical properties, such as low density, high specific strength, and good corrosion resistance. However, during forging processes, underfilling, folding, broken streamline, crack, coarse grain, and other macro- or microdefects are easily generated because of the deformation characteristics of aluminum alloys, including narrow forgeable temperature region, fast heat dissipation to dies, strong adhesion, high strain rate sensitivity, and large flow resistance. Thus, it is seriously restricted for the forged part to obtain precision shape and enhanced property. In this paper, progresses in precision forging technologies of aluminum alloy parts were reviewed. Several advanced precision forging technologies have been developed, including closed die forging, isothermal die forging, local loading forging, metal flow forging with relief cavity, auxiliary force or vibration loading, casting-forging hybrid forming, and stamping-forging hybrid forming. High-precision aluminum alloy parts can be realized by controlling the forging processes and parameters or combining precision forging technologies with other forming technologies. The development of these technologies is beneficial to promote the application of aluminum alloys in manufacturing of lightweight parts.

  5. A review of the effect of neutron irradiation on the deformation behaviour of copper and copper alloys

    International Nuclear Information System (INIS)

    Higgy, H.R.

    1976-08-01

    The basic mechanisms of irradiation hardening are described. The effects of neutron dose, alloying and pre-irradiation deformation on the deformation behaviour of neutron-irradiatied copper and its alloys are considered. The discrepancy in the reported data is discussed. Substitutional and interstitial additions are found to influence the rate of irradiation hardening, while pre-irradiation deformation has no influence. The deformation behaviour of copper is found to alter as a result of irradiation and alloying. (author)

  6. The physics of Martian weather and climate: a review.

    Science.gov (United States)

    Read, P L; Lewis, S R; Mulholland, D P

    2015-12-01

    The planet Mars hosts an atmosphere that is perhaps the closest in terms of its meteorology and climate to that of the Earth. But Mars differs from Earth in its greater distance from the Sun, its smaller size, its lack of liquid oceans and its thinner atmosphere, composed mainly of CO(2). These factors give Mars a rather different climate to that of the Earth. In this article we review various aspects of the martian climate system from a physicist's viewpoint, focusing on the processes that control the martian environment and comparing these with corresponding processes on Earth. These include the radiative and thermodynamical processes that determine the surface temperature and vertical structure of the atmosphere, the fluid dynamics of its atmospheric motions, and the key cycles of mineral dust and volatile transport. In many ways, the climate of Mars is as complicated and diverse as that of the Earth, with complex nonlinear feedbacks that affect its response to variations in external forcing. Recent work has shown that the martian climate is anything but static, but is almost certainly in a continual state of transient response to slowly varying insolation associated with cyclic variations in its orbit and rotation. We conclude with a discussion of the physical processes underlying these long- term climate variations on Mars, and an overview of some of the most intriguing outstanding problems that should be a focus for future observational and theoretical studies.

  7. The multiphase physics of sea ice: a review

    Science.gov (United States)

    Hunke, E. C.; Notz, D.; Turner, A. K.; Vancoppenolle, M.

    2011-07-01

    Rather than being solid throughout, sea ice contains liquid brine inclusions, solid salts, microalgae, trace elements, gases, and other impurities which all exist in the interstices of a porous, solid ice matrix. This multiphase structure of sea ice arises from the fact that the salt that exists in seawater cannot be embedded into the water-ice crystal lattice upon formation of sea ice, but remains in liquid solution. Depending on the ice porosity (determined by temperature and salinity), this brine can drain from the ice, taking other sea ice constituents with it. Thus, sea ice salinity and microstructure are tightly interconnected and play a significant role in polar ecosystems and climate. As large-scale climate modeling efforts move toward "earth system" simulations that include biological and chemical cycles, renewed interest in the multiphase physics of sea ice has strengthened research initiatives to observe, understand and model this complex system. This review article provides an overview of these efforts, highlighting known difficulties and requisite observations for further progress in the field. We focus on mushy-layer theory, which describes general multiphase materials, and on numerical approaches now being explored to model the multiphase evolution of sea ice and its interaction with chemical, biological and climate systems.

  8. Systematic review of recess interventions to increase physical activity.

    Science.gov (United States)

    Ickes, Melinda J; Erwin, Heather; Beighle, Aaron

    2013-08-01

    With the rapid increase in obesity rates among youth, efforts to increase physical activity (PA) have become a priority. School-based strategies for PA promotion must be cost-effective, unobtrusive, and linked to improved academic performance. Efforts to maximize recess PA are advocated because of both health and academic benefits. The purpose of this manuscript was to review recess interventions aimed to improve PA among youth, and make recommendations to develop related best practices. An extensive literature search was conducted to include all primary research articles evaluating any recess intervention with PA as an outcome. The included 13 interventions represented both settings within the U.S and internationally, among preschools and elementary/primary schools. A variety of strategies were used within the design and implementation of each of the interventions including: added equipment/materials, markings, zones, teacher involvement, active video games, activity of the week, and activity cards. Of the included studies, 95% demonstrated positive outcomes as a result of the recess intervention. A number of simple, low-cost strategies can be implemented to maximize the amount of recess time students are allotted. Long-term follow-up studies are warranted for each of the recess strategies identified to be effective.

  9. Google matrix of the citation network of Physical Review

    Science.gov (United States)

    Frahm, Klaus M.; Eom, Young-Ho; Shepelyansky, Dima L.

    2014-05-01

    We study the statistical properties of spectrum and eigenstates of the Google matrix of the citation network of Physical Review for the period 1893-2009. The main fraction of complex eigenvalues with largest modulus is determined numerically by different methods based on high-precision computations with up to p =16384 binary digits that allow us to resolve hard numerical problems for small eigenvalues. The nearly nilpotent matrix structure allows us to obtain a semianalytical computation of eigenvalues. We find that the spectrum is characterized by the fractal Weyl law with a fractal dimension df≈1. It is found that the majority of eigenvectors are located in a localized phase. The statistical distribution of articles in the PageRank-CheiRank plane is established providing a better understanding of information flows on the network. The concept of ImpactRank is proposed to determine an influence domain of a given article. We also discuss the properties of random matrix models of Perron-Frobenius operators.

  10. SCANUK. A collaborative programme to develop new zirconium cladding alloys

    International Nuclear Information System (INIS)

    Tyzack, C.; Hurst, P.; Slattery, G.F.

    1977-04-01

    The primary aim of the programme was to develop alloys with better performance than Zircaloy-2 under BWR/TWR conditions and specifically with improved resistance to short-term high temperature transients. Secondly, the alloys were to be capable of full-term reactor service over a wider temperature range than usual (up to 450 0 C). For the first objective a Zr-1 wt % Nb alloy was selected and for the second, alloys were composed of small amounts of chromium and/or molybdenum added to a base composition of 1/2 or 1 wt % niobium in zirconium. The test programme obtained on the physical metallurgy, mechanical properties and corrosion resistance of the alloys both before and after irradiation is described and the results are reviewed. Although the requirement for cladding to operate at elevated temperatures is not longer of prime importance, the development work has demonstrated that with some further optimisation some of the alloys might present a viable alternative to Zircaloy-2 for in-reactor operation at approximately 300 0 C in oxygenated coolants. With regard especially to nodular oxidation resistance these alloys, based on modest additions of niobium to zirconium, tend to be better than Zircaloy-2 but their performance does not consistently approach that of Zr-2 1/2% Nb. (author)

  11. Systematic, Evidence-Based Review of Exercise, Physical Activity, and Physical Fitness Effects on Cognition in Persons with Multiple Sclerosis.

    Science.gov (United States)

    Sandroff, Brian M; Motl, Robert W; Scudder, Mark R; DeLuca, John

    2016-09-01

    Cognitive dysfunction is highly prevalent, disabling, and poorly-managed in persons with multiple sclerosis (MS). Recent evidence suggests that exercise might have beneficial effects on cognition in this population. The current systematic, evidence-based review examined the existing literature on exercise, physical activity, and physical fitness effects on cognition in MS to accurately describe the current status of the field, offer recommendations for clinicians, and identify study-specific and participant-specific characteristics for providing future direction for ongoing MS research. We performed an open-dated search of Medline, PsychInfo, and CINAHL in December 2015. The search strategy involved using the terms 'exercise' OR 'physical activity' OR 'physical fitness' OR 'aerobic' OR 'resistance' OR 'balance' OR 'walking' OR 'yoga' OR 'training' OR 'rehabilitation' AND 'multiple sclerosis'. Articles were eliminated from the systematic review if it was a review article, theoretical paper, or textbook chapter; did not involve persons with MS; involved only persons with pediatric-onset MS; did not involve neuropsychological outcomes; did not include empirical data to evaluate outcomes; involved pharmacological interventions; or was not available in English. The selected articles were first classified as examining exercise, physical activity, or physical fitness, and were then randomly assigned to 2 independent reviewers who rated each article for level of evidence based on American Academy of Neurology criteria. Reviewers further completed a table to characterize important elements of each study (i.e., intervention characteristics), the cognitive domain(s) that were targeted, participant-specific characteristics, outcome measures, and study results. The present review resulted in 26 studies on the effects of exercise, physical activity, and physical fitness on cognition in persons with MS. This included 1 Class I study, 3 Class II studies, 8 Class III studies, and

  12. BOOK REVIEW: Introductory Nanoscience: Physical and Chemical Concepts Introductory Nanoscience: Physical and Chemical Concepts

    Science.gov (United States)

    Bich Ha, Nguyen

    2011-12-01

    main aims of the textbook. The book consists of 15 chapters. According to their detailed contents they can be divided into three groups. In five chapters forming the first group (Introduction, Structure, Length Scales, Types of Nanostructures, Absorption and Emission Basics) the author presents the notions, definitions and concepts related to nanosystems, as well as the length scales of all their physical parameters. The contents of these chapters have been written for all readers studying any undergraduate academic programme in natural sciences and engineering. The subsequent seven chapters forming the second group (A Quantum Mechanics Review, Model Quantum Mechanics Problems, Additional Model Problems, Density of States, Bands, Time-Dependent Perturbation Theory, Interband Transitions) contain a comprehensive and easily understandable presentation of the theoretical basics of nanoscience. The last three chapters (Synthesis, Characterization, Applications) contain presentations on the fundamental methods in the experimental studies and applications of nanosystems. This book is very useful not only for training beginners in research and engineering in nanoscience and nanotechnology, but also for attracting the interest of specialists in other scientific disciplines to the application of the achievements of this new emerging multidisciplinary scientific field.

  13. Magnetic susceptibility of Dirac fermions, Bi-Sb alloys, interacting Bloch fermions, dilute nonmagnetic alloys, and Kondo alloys

    Energy Technology Data Exchange (ETDEWEB)

    Buot, Felix A., E-mail: fbuot@gmu.edu [Computational Materials Science Center, George Mason University, Fairfax, VA 22030 (United States); TCSE Center, Spintronics Group, Physics Department, University of San Carlos, Talamban, Cebu 6000 (Philippines); C& LB Research Institute, Carmen, Cebu 6005 (Philippines); Otadoy, Roland E.S.; Rivero, Karla B. [TCSE Center, Spintronics Group, Physics Department, University of San Carlos, Talamban, Cebu 6000 (Philippines)

    2017-03-01

    Wide ranging interest in Dirac Hamiltonian is due to the emergence of novel materials, namely, graphene, topological insulators and superconductors, the newly-discovered Weyl semimetals, and still actively-sought after Majorana fermions in real materials. We give a brief review of the relativistic Dirac quantum mechanics and its impact in the developments of modern physics. The quantum band dynamics of Dirac Hamiltonian is crucial in resolving the giant diamagnetism of bismuth and Bi-Sb alloys. Quantitative agreement of the theory with the experiments on Bi-Sb alloys has been achieved, and physically meaningful contributions to the diamagnetism has been identified. We also treat relativistic Dirac fermion as an interband dynamics in uniform magnetic fields. For the interacting Bloch electrons, the role of translation symmetry for calculating the magnetic susceptibility avoids any approximation to second order in the field. The expressions for magnetic susceptibility of dilute nonmagnetic alloys give a firm theoretical foundation of the empirical formulas used in fitting experimental results. The unified treatment of all the above calculations is based on the lattice Weyl-Wigner formulation of discrete phase-space quantum mechanics. For completeness, the magnetic susceptibility of Kondo alloys is also given since Dirac fermions in conduction band and magnetic impurities exhibit Kondo effect.

  14. Physics Division annual review, 1 April 1977--31 March 1978

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-01-01

    This review of research activity for the year ending in April 1978 contains information on the following subjects: the superconducting linac, medium-energy physics, heavy-ion physics, charged-particle research, accelerator operations, neutron physics, theoretical physics, and experimental atomic and molecular physics. Lists of publications and personnel are also given. Twenty-one items with significant data were abstracted and indexed individually. 58 figures, 4 tables. (RWR)

  15. Tutorial for writing systematic reviews for the Brazilian Journal of Physical Therapy (BJPT

    Directory of Open Access Journals (Sweden)

    Marisa C. Mancini

    2014-12-01

    Full Text Available Systematic reviews aim to summarize all evidence using very rigorous methods in order to address a specific research question with less bias as possible. Systematic reviews are widely used in the field of physical therapy, however not all reviews have good quality. This tutorial aims to guide authors of the Brazilian Journal of Physical Therapy on how systematic reviews should be conducted and reported in order to be accepted for publication. It is expected that this tutorial will help authors of systematic reviews as well as journal editors and reviewers on how to conduct, report, critically appraise and interpret this type of study design.

  16. Tutorial for writing systematic reviews for the Brazilian Journal of Physical Therapy (BJPT).

    Science.gov (United States)

    Mancini, Marisa C; Cardoso, Jefferson R; Sampaio, Rosana F; Costa, Lucíola C M; Cabral, Cristina M N; Costa, Leonardo O P

    2014-01-01

    Systematic reviews aim to summarize all evidence using very rigorous methods in order to address a specific research question with less bias as possible. Systematic reviews are widely used in the field of physical therapy, however not all reviews have good quality. This tutorial aims to guide authors of the Brazilian Journal of Physical Therapy on how systematic reviews should be conducted and reported in order to be accepted for publication. It is expected that this tutorial will help authors of systematic reviews as well as journal editors and reviewers on how to conduct, report, critically appraise and interpret this type of study design.

  17. Tutorial for writing systematic reviews for the Brazilian Journal of Physical Therapy (BJPT)

    Science.gov (United States)

    Mancini, Marisa C.; Cardoso, Jefferson R.; Sampaio, Rosana F.; Costa, Lucíola C. M.; Cabral, Cristina M. N.; Costa, Leonardo O. P.

    2014-01-01

    Systematic reviews aim to summarize all evidence using very rigorous methods in order to address a specific research question with less bias as possible. Systematic reviews are widely used in the field of physical therapy, however not all reviews have good quality. This tutorial aims to guide authors of the Brazilian Journal of Physical Therapy on how systematic reviews should be conducted and reported in order to be accepted for publication. It is expected that this tutorial will help authors of systematic reviews as well as journal editors and reviewers on how to conduct, report, critically appraise and interpret this type of study design. PMID:25590440

  18. Review of creep deformation and rupture mechanism of P91 alloy for the development of creep damage constitutive equations under low stress level

    OpenAIRE

    An, Lili; Xu, Qiang; Xu, Donglai; Lu, Zhongyu

    2013-01-01

    This paper presents a review of creep deformation and rupture mechanism of P91 alloy for the development of its creep damage constitutive equations under lower stress level. Creep damage is one of the serious problems for the high temperature industries and computational approach (such as continuum damage mechanics) has been developed and used, complementary to the experimental approach, to assist safe operation. However, there are no ready creep damage constitutive equations to be used for p...

  19. 77 FR 69505 - Proposal Review Panel for Physics; Notice of Meeting

    Science.gov (United States)

    2012-11-19

    ... NATIONAL SCIENCE FOUNDATION Proposal Review Panel for Physics; Notice of Meeting In accordance with the Federal Advisory Committee Act (Pub. L. 92- 463, as amended), the National Science Foundation announces the following meeting. Name: LIGO Operations Proposal and Annual Review in Physics (1208). Date...

  20. Determinants of physical activity in university students: a literary review

    Directory of Open Access Journals (Sweden)

    Ana Isabel Caro-Freile

    2017-05-01

    Full Text Available Physical activity refers to the body movement that generates energy expenditure, its frequent practice improves physical and mental functions; Active transportation, daily activities and recreation correspond to the most common form of physical activity. In Colombia the majority of the population is inactive, children are more active, but this condition decreases with age, the percentage of college students who engage in physical activity is low, this practice is conditioned by internal motivation, physical condition, Availability of time and social support. The taste for sports, the competitive spirit, the improvement of the corporal image, the management of the stress and the benefits for the health are motivating factors for the practice of the physical activity in university students; On the other hand, laziness, fear of injury, lack of sports scenarios and insecurity of the environment are the most frequent barriers to physical activity in this population

  1. Promoting physical activity in preschoolers to prevent obesity: a review of the literature.

    Science.gov (United States)

    Hodges, Eric A; Smith, Cecily; Tidwell, Stacy; Berry, Diane

    2013-01-01

    This literature review summarizes clinical recommendations for adequate physical activity and reviews recently published studies that focus on identifying common factors associated with physical activity levels among preschoolers in the United States and Canada. Currently, there is inconsistency in both the definition of and recommendations for physical activity. In addition, there is relatively little research in this area. Common factors and contexts associated with physical activity levels in preschoolers in this review included (a) child characteristics; (b) interpersonal dynamics between preschoolers and their families, childcare providers, and health care providers; (c) childcare setting; and (d) neighborhood environment. Copyright © 2013 Elsevier Inc. All rights reserved.

  2. Effect of recasting of nickel-chromium alloy on its porosity

    Directory of Open Access Journals (Sweden)

    Jayant Palaskar

    2010-01-01

    Full Text Available Statement of Problem: As per the review of literature very few studies have been carried on recasting of dental casting alloy and in particlular its effect on occurrence of porosities. Purpose of Study: This study was designed to find out occurrence of porosities in new alloy and recasted alloy using a scanning electron microscope. Materials and Methods: Different percentage combinations of new and once casted alloy were used to produce twenty five samples. Castings obtained from new alloy were used as control group. All the samples were scanned under scanning electron mocroscope and photographs were taken from three specific sites for comparison. Results: There is no significant difference in occurrence of porosities in casting obtained by using new alloy and recasted alloy. Conclusion: With in the limitations of the study it is conducted that the prorosities will not be affected by recasting of neckel-chromium alloy. Clinical Implication: Porosities in dental casting alloy can alter physical and mechanical properties of the mental which inturn may lead to failure of crown and bridge, and also cast partial denture prosthesis.

  3. Silicon-substituted hydroxyapatite coating with Si content on the nanotube-formed Ti–Nb–Zr alloy using electron beam-physical vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Yong-Hoon [Division of Restorative, Prosthetic and Primary Care Dentistry, College of Dentistry, The Ohio State University, 305 W. 12th Ave., Columbus, OH (United States); Department of Dental Materials, Research Center of Nano-Interface Activation for Biomaterials, and Research Center for Oral Disease Regulation of the Aged, School of Dentistry, Chosun University, Gwangju (Korea, Republic of); Choe, Han-Cheol, E-mail: hcchoe@chosun.ac.kr [Department of Dental Materials, Research Center of Nano-Interface Activation for Biomaterials, and Research Center for Oral Disease Regulation of the Aged, School of Dentistry, Chosun University, Gwangju (Korea, Republic of); Brantley, William A. [Division of Restorative, Prosthetic and Primary Care Dentistry, College of Dentistry, The Ohio State University, 305 W. 12th Ave., Columbus, OH (United States)

    2013-11-01

    The purpose of this study was to investigate the electrochemical characteristics of silicon-substituted hydroxyapatite coatings on the nanotube-formed Ti–35Nb–10Zr alloy. The silicon-substituted hydroxyapatite (Si–HA) coatings on the nanotube structure were deposited by electron beam-physical vapor deposition and anodization methods, and biodegradation properties were analyzed by potentiodynamic polarization and electrochemical impedance spectroscopy measurement. The surface characteristics were analyzed by field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy and X-ray diffraction (XRD). The Si–HA layers were deposited with rough features having highly ordered nanotube structures on the titanium alloy substrate. The thickness of the Si–HA coating was less than that of the HA coating. The XRD results confirmed that the Si–HA coating on the nanotube structure consisted of TiO{sub 2} anatase, TiO{sub 2} rutile, hydroxyapatite, and calcium phosphate silicate. The Si–HA coating surface exhibited lower I{sub corr} than the HA coating, and the polarization resistance was increased by substitution of silicon in hydroxyapatite. - Highlights: • Silicon substituted hydroxyapatite (Si–HA) was coated on nanotubular titanium alloy. • The Si–HA coating thickness was less than single hydroxyapatite (HA) coating. • Si–HA coatings consisted of TiO{sub 2}, HA, and Ca{sub 5}(PO{sub 4}){sub 2}SiO{sub 4}. • Polarization resistance of the coating was increased by Si substitution in HA.

  4. Welding of refractory alloys

    International Nuclear Information System (INIS)

    Lessmann, G.G.

    1984-01-01

    This review primarily summarizes welding evaluations supported by NASA-Lewis Research Center in the 1960s. A literature search run in preparation for this review indicates that more recent work is modest by comparison. Hence, this review restates these accomplishments briefly and addresses opportunities which have evolved in welding technology (such as lasers) in the intervening decade. Emphasis in this review is given to tantalum- and niobium-base alloys. Considerable work was also done to assure that a consistent comparison was made with tungsten. A wide variety of candidate alloys derived primarily from developments directed at aircraft propulsion applications were available. Early efforts by NASA were directed at screening studies to select promising structural alloys for the space power application. This objective required fine tuning of welding procedures, e.g., the demonstration of stringent standards for control of welding atmosphere to assure good corrosion resistance in liquid alkali metals. 16 figures, 6 tables

  5. Impact of Physical Activity Intervention Programs on Self-Efficacy in Youths: A Systematic Review

    OpenAIRE

    Cataldo, Rosa; John, Janice; Chandran, Latha; Pati, Susmita; Shroyer, A. Laurie W.

    2013-01-01

    Lack of physical activity has contributed to the nation’s childhood obesity crisis, but the impact of physical activity on self-efficacy as a mediator of behavior change has not been examined. This systematic review (SR) describes the published evidence related to the impact of physical activity intervention programs on self-efficacy among youths. From January 2000 to June 2011, the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) standards were used to identify pub...

  6. 78 FR 25101 - Proposal Review Panel for Physics, Notice of Meeting

    Science.gov (United States)

    2013-04-29

    ... NATIONAL SCIENCE FOUNDATION Proposal Review Panel for Physics, Notice of Meeting In accordance... Physics, 1208 Date and Time: Tuesday, April 30, 2013; 8:00 a.m.-6:00 p.m., Wednesday, May 1, 2013, 8:00 a... Meeting: Partially Closed. Contact Person: Mark Coles, Director of Large Facilities, Division of Physics...

  7. Measuring Physical Activity in Children and Youth Living with Intellectual Disabilities: A Systematic Review

    Science.gov (United States)

    Hinckson, Erica Aneke; Curtis, Amy

    2013-01-01

    Accurate assessment of physical activity is necessary in determining levels of physical activity in children living with intellectual disability (ID) and assessing effectiveness of intervention programmes. A systematic review of measures of physical activity in children with ID was undertaken using the PRISMA guidelines. MEDLINE-PubMed, Scopus,…

  8. 75 FR 63865 - Proposal Review Panel for Physics; Notice of Meeting

    Science.gov (United States)

    2010-10-18

    ... Proposal Review Panel for Physics; Notice of Meeting In accordance with the Federal Advisory Committee Act...: Michigan State University Site Visit in Physics (1208). Date and Time: Tuesday, November 9, 2010; 8 a.m.-6... Elementary Particle Physics, National Science Foundation, 4201 Wilson Blvd., Arlington, VA 22230. Telephone...

  9. 75 FR 3493 - Proposal Review Panel for Physics; Notice of Meeting

    Science.gov (United States)

    2010-01-21

    ... FOUNDATION Proposal Review Panel for Physics; Notice of Meeting In accordance with the Federal Advisory.... Name: University of Nebraska Site Visit in Physics (1208). Date and Time: Monday, February 1, 2010; 8 a... Particle Physics, National Science Foundation, 4201 Wilson Blvd., Arlington, VA 22230. Telephone: (703) 292...

  10. 75 FR 67142 - Proposal Review Panel for Physics; Notice of Meeting

    Science.gov (United States)

    2010-11-01

    ... Proposal Review Panel for Physics; Notice of Meeting In accordance with the Federal Advisory Committee Act...: Site Visit to the Center for the Physics of Living Cells 1208. Dates/Time: November 8, 2010, 9 a.m.- 4... advice and recommendations concerning progress of the Center for the Physics of Living Cells (CPLC...

  11. A systematic review of reliability and objective criterion-related validity of physical activity questionnaires

    NARCIS (Netherlands)

    Helmerhorst, Hendrik J. F.; Brage, Søren; Warren, Janet; Besson, Herve; Ekelund, Ulf

    2012-01-01

    Physical inactivity is one of the four leading risk factors for global mortality. Accurate measurement of physical activity (PA) and in particular by physical activity questionnaires (PAQs) remains a challenge. The aim of this paper is to provide an updated systematic review of the reliability and

  12. The Benefits of Active Video Games for Educational and Physical Activity Approaches: A Systematic Review

    Science.gov (United States)

    Merino Campos, Carlos; del Castillo Fernández, Héctor

    2016-01-01

    This article sets out to conduct a systematic review of the current literature on active video games as potential educational tools for physical education or physical activity. To begin with, research on active video games for educational and physical purposes has been examined with the purpose of verifying improvement of attitudes, intellectual…

  13. BOOK REVIEW: Introduction to Black Hole Physics Introduction to Black Hole Physics

    Science.gov (United States)

    Tanaka, Takahiro

    2012-07-01

    Introduction to Black Hole Physics is a large volume (504 pages), and yet despite this it is still really an introductory text. The book gives an introduction to general relativity, but most of the text is dedicated to attracting the reader's attention to the interesting world of black hole physics. In this sense, the book is very distinct from other textbooks on general relativity. We are told that it was based on the lectures given by Professor Frolov, one of the authors, over the last 30 years. One can obtain the basic ideas about black holes, and also the necessary tips to understand general relativity at a very basic level. For example, in the discussion about particle motion in curved space, the authors start with a brief review on analytical mechanics. The book does not require its readers to have a great deal of knowledge in advance. If you are familiar with such a basic subject, you can simply omit that section. The reason why I especially picked up on this topic as an example is that the book devotes a significant number of pages to geodesic motions in black hole spacetime. One of the main motivations to study black holes is related to how they will actually be observed, once we develop the ability to observe them clearly. The book does explain such discoveries as, for instance, how the motion of a particle is related to a beautiful mathematical structure arising from the hidden symmetry of spacetime, which became transparent via the recent progress in the exploration of black holes in higher dimensions; a concise introduction to this latest topic is deferred to Appendix D, so as not to distract the reader with its mathematical complexities. It should be also mentioned that the book is not limited to general relativistic aspects: quantum fields on a black hole background and Hawking radiation are also covered. Also included are current hot topics, for instance the gravitational waves from a system including black holes, whose first direct detection is

  14. BOOK REVIEW: Key Science Physics: New Edition and Key Science Physics for International Schools: Extension File

    Science.gov (United States)

    Maybank, Maureen

    1999-09-01

    When handling , I recalled how one set of sixth-form students that I taught affectionately referred to Jim Breithaupt's large format book Understanding Physics for Advanced Level as `Big Jim'. This package, for GCSE students and teachers, is its younger brother. Key Science Physics was reviewed in this journal over four years ago. Now it is in a new edition with an expanded ring file of teacher resources (a Teacher's Guide and Extension File). It has been expanded for a wider range of students to meet the requirements of all GCSE syllabuses with additional topics for IGCSE and IB. The international bit seems to be among materials in the file of resources and does not appear in the title of the students' textbook. This is not one of those purchases that will only get occasional use and be left in a department library but it is one that contains sufficient excellent material to become central to any GCSE Physics course. For the students there is a single-volume 396-page textbook in full colour (not a heavyweight book). Marginal comments point out places where an Activity or Assignment from the Extension File fits in. All the materials in the teacher's Extension File are cross referenced to the numbering of this textbook, i.e. its Themes, Topics, Checkpoints, Tests etc, not to page numbers. The margin is used in other attractive ways to highlight a summary, propose a first thought or provide a topic summary. The text is fruitful mix of pure physics, applications and personalities. To support the students' practical work the Extension File contains photocopiable sheets. For the activities and assignments a few contain a harder version to give access to the higher levels of attainment. Four alternatives to practical questions are given; there are also exam questions and multiple choice questions for each topic. These all have helpful mark schemes on the teacher's answers pages. What else do you get? A Glossary collection of sheets to photocopy with space to enter a

  15. Adaptive Review of Three Fundamental Questions in Physics

    DEFF Research Database (Denmark)

    Javadi, Hossein; Forouzbakhsh, Farshid; Daei Kasmaei, Hamed

    2016-01-01

    principle. Included in the sub quantum scale, where quantum interactions between photons and gravitons done. Hidden and dark side of modern physics is also a place where charged particles absorb and emit energy quanta, without any description of the mechanism of absorption and emission by charged particles....... Perhaps it is only a part of a bigger picture of the modern physics which includes the deeper and hidden layer of subatomic world that has been dipped into the darkness of the universe. The question is, where is the hidden part of modern physics? Hidden part of modern physics lies beyond the uncertainty...

  16. Simultaneous evaluation of physical and social environmental correlates of physical activity in adults: A systematic review

    Directory of Open Access Journals (Sweden)

    Alexia Sawyer

    2017-12-01

    Conclusions: Inconsistent evidence of independent associations between environmental variables and physical activity could be partly due to unmeasured effect modification (e.g. interactive effects creating unaccounted variance in relationships between the environment and activity. Results supported multiple levels of environmental influence on physical activity. It is recommended that further research uses simultaneous or interaction analyses to gain insight into complex relationships between neighbourhood social and physical environments and physical activity, as there is currently limited research in this area.

  17. Literature Review: Weldability of Iridium DOP-26 Alloy for General Purpose Heat Source

    Energy Technology Data Exchange (ETDEWEB)

    Burgardt, Paul [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Pierce, Stanley W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-10-19

    The basic purpose of this paper is to provide a literature review relative to fabrication of the General Purpose Heat Source (GPHS) that is used to provide electrical power for deep space missions of NASA. The particular fabrication operation to be addressed here is arc welding of the GPHS encapsulation. A considerable effort was made to optimize the fabrication of the fuel pellets and of other elements of the encapsulation; that work will not be directly addressed in this paper. This report consists of three basic sections: 1) a brief description of the GPHS will be provided as background information for the reader; 2) mechanical properties and the optimization thereof as relevant to welding will be discussed; 3) a review of the arc welding process development and optimization will be presented. Since the welding equipment must be upgraded for future production, some discussion of the historical establishment of relevant welding variables and possible changes thereto will also be discussed.

  18. Evolution of the electronic structure and physical properties of Fe2MeAl (Me = Ti, V, Cr) Heusler alloys

    International Nuclear Information System (INIS)

    Shreder, E; Streltsov, S V; Svyazhin, A; Makhnev, A; Marchenkov, V V; Lukoyanov, A; Weber, H W

    2008-01-01

    We present the results of experiments on the optical, electrical and magnetic properties and electronic structure and optical spectrum calculations of the Heusler alloys Fe 2 TiAl, Fe 2 VAl and Fe 2 CrAl. We find that the drastic transformation of the band spectrum, especially near the Fermi level, when replacing the Me element (Me = Ti, V, Cr), is accompanied by a significant change in the electrical and optical properties. The electrical and optical properties of Fe 2 TiAl are typical for metals. The abnormal behavior of the electrical resistivity and the optical properties in the infrared range for Fe 2 VAl and Fe 2 CrAl are determined by electronic states at the Fermi level. Both the optical spectroscopic measurements and the theoretical calculations demonstrate the presence of low-energy gaps in the band spectrum of the Heusler alloys. In addition, we demonstrate that the formation of Fe clusters may be responsible for the large enhancement of the total magnetic moment in Fe 2 CrAl

  19. The effect of neutron spectrum on the mechanical and physical properties of pure copper and copper alloys

    International Nuclear Information System (INIS)

    Fabritsiev, S.A.; Pokrovsky, A.S.; Sandakov, V.A.; Zinkle, S.J.; Rowcliffe, A.F.; Edwards, D.J.; Garner, F.A.; Singh, B.N.; Barabash, V.R.

    1996-01-01

    The electrical resistivity and tensile properties of copper and oxide dispersion strengthened (DS) copper alloys have been measured before and after fission neutron irradiation to damage levels of 0.5 to 5 displacements per atom (dps) at ∼100 to 400 degrees C. Some of the specimens were irradiated inside a 1.5 mm Cd shroud in order to reduce the thermal neutron flux. The electrical resistivity data could be separated into two components, a solid transmutation component Δρ tr which was proportional to thermal neutron fluence and a radiation defect component Δρ rd which was independent of the displacement dose. The saturation value for Δρ rd was ∼1.2 nanohm-meters for pure copper and ∼1.6 nanohm-meters for the DS copper alloys irradiated at 100 degrees C in positions with a fast-to-thermal neutron flux ratio of 5. Considerable radiation hardening was observed in all specimens at irradiation temperatures below 200 degrees C. The yield strength was relatively insensitive to neutron spectrum in specimens strengthened by dispersoids or cold- working. 17 refs., 7 figs., 1 tab

  20. Development of Biomimetic NiTi Alloy: Influence of Thermo-Chemical Treatment on the Physical, Mechanical and Biological Behavior

    Directory of Open Access Journals (Sweden)

    Elisa Rupérez

    2016-05-01

    Full Text Available A bioactive layer, free of nickel, has been performed for its greater acceptability and reliability in clinical applications for NiTi shape memory alloys. In the first step, a safe barrier against Ni release has been produced on the surface by means of a thicker rutile/anastase protective layer free of nickel. In the second step, a sodium alkaline titanate hydrogel, which has the ability to induce apatite formation, has been performed from oxidized surface. An improvement of host tissue–implant integration has been achieved in terms of Ni ions release and the bioactivity of the treated NiTi alloys has been corroborated with both in vitro and in vivo studies. The transformation temperatures (As, Af, Ms, and Mf, as well as the critical stresses (σβ⇔M, have been slightly changed due to this surface modification. Consequently, this fact must be taken into account in order to design new surface modification on NiTi implants.

  1. Development of Biomimetic NiTi Alloy: Influence of Thermo-Chemical Treatment on the Physical, Mechanical and Biological Behavior

    Science.gov (United States)

    Rupérez, Elisa; Manero, José María; Bravo-González, Luis-Alberto; Espinar, Eduardo; Gil, F.J.

    2016-01-01

    A bioactive layer, free of nickel, has been performed for its greater acceptability and reliability in clinical applications for NiTi shape memory alloys. In the first step, a safe barrier against Ni release has been produced on the surface by means of a thicker rutile/anastase protective layer free of nickel. In the second step, a sodium alkaline titanate hydrogel, which has the ability to induce apatite formation, has been performed from oxidized surface. An improvement of host tissue–implant integration has been achieved in terms of Ni ions release and the bioactivity of the treated NiTi alloys has been corroborated with both in vitro and in vivo studies. The transformation temperatures (As, Af, Ms, and Mf), as well as the critical stresses (σβ⇔M), have been slightly changed due to this surface modification. Consequently, this fact must be taken into account in order to design new surface modification on NiTi implants. PMID:28773526

  2. The effect of neutron spectrum on the mechanical and physical properties of pure copper and copper alloys

    DEFF Research Database (Denmark)

    Fabritsiev, S.A.; Pokrovsky, A.S.; Zinkle, S.J.

    1996-01-01

    The electrical resistivity and tensile properties of copper and oxide dispersion strengthened (DS) copper alloys have been measured before and after fission neutron irradiation to damage levels of 0.5 to 5 displacements per atom (dpa) at similar to 100 to 400 degrees C. Some of the specimens were......-irradiated inside a 1.5 mm Cd shroud in order to reduce the thermal neutron flux. The electrical resistivity data could be separated into two components, a solid transmutation component Delta rho(tr) which was proportional to thermal neutron fluence and a radiation defect component Delta rho(rd) which...... was independent of displacement dose. The saturation value for Delta rho(rd) was similar to 1.2 n Omega m for pure copper and similar to 1.6 n Omega m for the DS copper alloys irradiated at 100 degrees C in positions with a fast-to-thermal neutron flux ratio of 5, Considerable radiation hardening was observed...

  3. Shape memory alloys – characterization techniques

    Indian Academy of Sciences (India)

    Abstract. Shape memory alloys are the generic class of alloys that show both thermal and mechan- ical memory. The basic physics involved in the shape memory effect is the reversible thermoelastic martensitic transformation. In general, there exists two phases in shape memory alloys, viz., a high- temperature phase or ...

  4. Shape memory alloys – characterization techniques

    Indian Academy of Sciences (India)

    Shape memory alloys are the generic class of alloys that show both thermal and mechanical memory. The basic physics involved in the shape memory effect is the reversible thermoelastic martensitic transformation. In general, there exists two phases in shape memory alloys, viz., a hightemperature phase or austenitic ...

  5. [Physical activity and cancer: Update and literature review].

    Science.gov (United States)

    Desnoyers, A; Riesco, E; Fülöp, T; Pavic, M

    2016-06-01

    Physical activity is a key determinant of public health and contributes to decreasing the prevalence of many diseases. Cancer is the leading cause of death worldwide. Physical activity, accessible to the entire population, could prevent up to 25% of cancers, in addition to improving survival rates and quality of life in cancer patients. Physical activity acts via various mechanisms to slow or decrease tumor growth, including the production and bioavailability of sex hormones, insulin resistance and insulin secretion, and inflammation. In primary prevention, physical activity reduces breast cancer risk by 15-20% and colorectal cancer risk by 24%. All-cause mortality is reduced by 33% in cancer survivors who exercise. Health-related quality of life, fatigue and depression are enhanced by the practice of physical activity in cancer patients. In the general population, the global recommendations on physical activity for health, published by the World Health Organisation, are suggested as a means of primary prevention of cancer. In cancer patients, an adapted physical activity routine is promoted from the very beginning of patient care to decrease fatigue as well as improve tolerance and benefits of treatments. Copyright © 2015 Société Nationale Française de Médecine Interne (SNFMI). Published by Elsevier SAS. All rights reserved.

  6. Physical Activity in Kidney Transplant Recipients: A Review.

    Science.gov (United States)

    Takahashi, Ashley; Hu, Susie L; Bostom, Andrew

    2018-02-23

    Physical activity has known health benefits and is associated with reduced cardiovascular risk in the general population. Relatively few data are available for physical activity in kidney transplant recipients. Compared to the general population, physical activity levels are lower overall in kidney recipients, although somewhat higher compared to the dialysis population. Recipient comorbid condition, psychosocial and socioeconomic factors, and long-term immunosuppression use negatively affect physical activity. Physical inactivity in kidney recipients may be associated with reduced quality of life, as well as increased mortality. Interventions such as exercise training appear to be safe in kidney transplant recipients and are associated with improved quality of life and exercise capacity. Additional studies are required to evaluate long-term effects on cardiovascular risk factors and ultimately cardiovascular disease outcomes and patient survival. Currently available data are characterized by wide variability in the interventions and outcome measures investigated in studies, as well as use of small sample-sized cohorts. These limitations highlight the need for larger studies using objective and standardized measures of physical activity and physical fitness in kidney transplant recipients. Copyright © 2018 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

  7. Physical Activity in Community Dwelling Older People: A Systematic Review of Reviews of Interventions and Context.

    Directory of Open Access Journals (Sweden)

    Olawale Olanrewaju

    Full Text Available The promotion and maintenance of higher physical activity (PA levels in the older population is an imperative for cognitive and healthy ageing but it is unclear what approaches are best suited to achieve this for the increasing number of older people living in the community. Effective policies should be informed by robust, multi-disciplinary and multi-dimensional evidence, which not only seeks what works, but in 'what context? In addition to evidence on the efficacy and effectiveness of PA for maintaining cognitive health, social contexts such as 'how do we actually get older people to partake in PA?' and 'how do we sustain that activity long-term?' also need highlighting. This review is part of a comprehensive evidence synthesis of preventive interventions in older age, with a focus on healthy behaviours to identify evidence gaps and inform policy relating to ageing well and cognitive health. An overview of systematic reviews of PA was conducted to explore three topics: (1 PA efficacy or effectiveness for primary prevention of cognitive decline in 55+; (2 Interventions efficacious or effective for increasing PA uptake and maintenance in 55+; (3 barriers and facilitators to PA in 55+.Multiple databases were searched for studies in English from OECD countries between 2000 and 2016. Quality of included reviews in questions (1 and (2 were assessed using AMSTAR. Review protocols were registered on PROSPERO (CRD42014015554, 42014015584, CRD42014015557 and reviews follow PRISMA guideline.Overall, 40 systematic reviews were included. Question 1 (n = 14. 8,360 participants. Evidence suggests that PA confer mild positive effects on cognition in older adults with and without previous cognitive impairment. However, there is insufficient evidence of a dose-response relationship. Evidence on the effects of PA on delay of dementia onset is inconclusive. Question 2 (n = 17. 79,650 participants. Evidence supports the effectiveness of a variety of interventions

  8. New Ti-Alloys and Surface Modifications to Improve the Mechanical Properties and the Biological Response to Orthopedic and Dental Implants: A Review

    Science.gov (United States)

    Kirmanidou, Yvoni; Sidira, Margarita; Drosou, Maria-Eleni; Bennani, Vincent; Bakopoulou, Athina; Tsouknidas, Alexander; Michailidis, Nikolaos; Michalakis, Konstantinos

    2016-01-01

    Titanium implants are widely used in the orthopedic and dentistry fields for many decades, for joint arthroplasties, spinal and maxillofacial reconstructions, and dental prostheses. However, despite the quite satisfactory survival rates failures still exist. New Ti-alloys and surface treatments have been developed, in an attempt to overcome those failures. This review provides information about new Ti-alloys that provide better mechanical properties to the implants, such as superelasticity, mechanical strength, and corrosion resistance. Furthermore, in vitro and in vivo studies, which investigate the biocompatibility and cytotoxicity of these new biomaterials, are introduced. In addition, data regarding the bioactivity of new surface treatments and surface topographies on Ti-implants is provided. The aim of this paper is to discuss the current trends, advantages, and disadvantages of new titanium-based biomaterials, fabricated to enhance the quality of life of many patients around the world. PMID:26885506

  9. New Ti-Alloys and Surface Modifications to Improve the Mechanical Properties and the Biological Response to Orthopedic and Dental Implants: A Review

    Directory of Open Access Journals (Sweden)

    Yvoni Kirmanidou

    2016-01-01

    Full Text Available Titanium implants are widely used in the orthopedic and dentistry fields for many decades, for joint arthroplasties, spinal and maxillofacial reconstructions, and dental prostheses. However, despite the quite satisfactory survival rates failures still exist. New Ti-alloys and surface treatments have been developed, in an attempt to overcome those failures. This review provides information about new Ti-alloys that provide better mechanical properties to the implants, such as superelasticity, mechanical strength, and corrosion resistance. Furthermore, in vitro and in vivo studies, which investigate the biocompatibility and cytotoxicity of these new biomaterials, are introduced. In addition, data regarding the bioactivity of new surface treatments and surface topographies on Ti-implants is provided. The aim of this paper is to discuss the current trends, advantages, and disadvantages of new titanium-based biomaterials, fabricated to enhance the quality of life of many patients around the world.

  10. PHYSICS

    CERN Multimedia

    D. Futyan

    A lot has transpired on the “Physics” front since the last CMS Bulletin. The summer was filled with preparations of new Monte Carlo samples based on CMSSW_3, the finalization of all the 10 TeV physics analyses [in total 50 analyses were approved] and the preparations for the Physics Week in Bologna. A couple weeks later, the “October Exercise” commenced and ran through an intense two-week period. The Physics Days in October were packed with a number of topics that are relevant to data taking, in a number of “mini-workshops”: the luminosity measurement, the determination of the beam spot and the measurement of the missing transverse energy (MET) were the three main topics.  Physics Week in Bologna The second physics week in 2009 took place in Bologna, Italy, on the week of Sep 7-11. The aim of the week was to review and establish how ready we are to do physics with the early collisions at the LHC. The agenda of the week was thus pac...

  11. PHYSICS

    CERN Multimedia

    D. Futyan

    A lot has transpired on the “Physics” front since the last CMS Bulletin. The summer was filled with preparations of new Monte Carlo samples based on CMSSW_3, the finalization of all the 10 TeV physics analyses [in total 50 analyses were approved] and the preparations for the Physics Week in Bologna. A couple weeks later, the “October Exercise” commenced and ran through an intense two-week period. The Physics Days in October were packed with a number of topics that are relevant to data taking, in a number of “mini-workshops”: the luminosity measurement, the determination of the beam spot and the measurement of the missing transverse energy (MET) were the three main topics.   Physics Week in Bologna The second physics week in 2009 took place in Bologna, Italy, on the week of Sep 7-11. The aim of the week was to review and establish (we hoped) the readiness of CMS to do physics with the early collisions at the LHC. The agenda of the...

  12. [recommendations For Physical Exercise Practice During Pregnancy: A Critical Review].

    OpenAIRE

    do Nascimento, Simony Lira; Godoy, Ana Carolina; Surita, Fernanda Garanhani; Pinto e Silva, João Luiz

    2015-01-01

    Physical exercise is recommended for all healthy pregnant women. Regular practice of exercises during pregnancy can provide many physical and psychological benefits, with no evidence of adverse outcomes for the fetus or the newborn when exercise is performed at mild to moderate intensity. However, few pregnant women engage in this practice and many still have fears and doubts about the safety of exercise. The objective of the present study was to inform the professionals who provide care for ...

  13. An Evaluation of the Physical Environments of a Nuclear Power Plants for Human Factors Review in Periodic Safety Review

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dae Ho; Lee, Yong Hee [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    2006-07-01

    Currently, operation of a nuclear power plants(NPP) is highly emphasized by the integrity of the H/W and the human factors security, so the periodic safety review(PSR) is performed to NPP. The PSR activities on human factors include physical environments (illumination, noise, vibration, temperature and humidity etc). The review on these physical environments is to verify the possible affect to the human error during the operation of the man machine interface. Physical environments affect the health, job stress and job satisfaction of NPP's employees. On the ground of the reason, we need integrating the management program for the sufficient satisfaction of the regulatory basis and standards of physical environment and considering a health, a job stress and satisfaction of NPP's employees. So, this paper describes the planning of the setup procedures of physical environments and the adequate management program for the field applications in NPPs.

  14. An Evaluation of the Physical Environments of a Nuclear Power Plants for Human Factors Review in Periodic Safety Review

    International Nuclear Information System (INIS)

    Kim, Dae Ho; Lee, Yong Hee

    2006-01-01

    Currently, operation of a nuclear power plants(NPP) is highly emphasized by the integrity of the H/W and the human factors security, so the periodic safety review(PSR) is performed to NPP. The PSR activities on human factors include physical environments (illumination, noise, vibration, temperature and humidity etc). The review on these physical environments is to verify the possible affect to the human error during the operation of the man machine interface. Physical environments affect the health, job stress and job satisfaction of NPP's employees. On the ground of the reason, we need integrating the management program for the sufficient satisfaction of the regulatory basis and standards of physical environment and considering a health, a job stress and satisfaction of NPP's employees. So, this paper describes the planning of the setup procedures of physical environments and the adequate management program for the field applications in NPPs

  15. ReviewsGCSE Book Review: Modular Science for AQA GCSE Book Review: Modular Science for Edexcel GCSE Book Review: Revise for GCSE Science (Edexcel Modular Foundation and Higher) GCSE Book Review: AQA GCSE Physics, AQA GCSE Physics Additions Book Review: Studying Maths and its Applications Book Review: Medical Physics, 2nd edition Book Review: The Physics of Hockey Book Review: Nine Crazy Ideas In Science Book Review: Light and Dark Talking Point: The Skeptical Environmentalist Places To Visit: Centre for Alternative Technology, Machynlleth, Powys Resources: Sources of Energy Web Watch: Terence, this is stupid stuff...

    Science.gov (United States)

    2003-03-01

    GCSE BOOK REVIEWS (162) Modular Science for AQA Modular Science for Edexcel Revise for GCSE Science (Edexcel Modular Foundation and Higher) AQA GCSE Physics, AQA GCSE Physics Additions BOOK REVIEWS (166) Studying Maths and its Applications Medical Physics, 2nd edition The Physics of Hockey Nine Crazy Ideas In Science Light and Dark TALKING POINT (169) The Skeptical Environmentalist PLACES TO VISIT (170) Centre for Alternative Technology, Machynlleth, Powys RESOURCES (172) Sources of Energy WEB WATCH (173) Terence, this is stupid stuff...

  16. The effectiveness of pretreatment physics plan review for detecting errors in radiation therapy.

    Science.gov (United States)

    Gopan, Olga; Zeng, Jing; Novak, Avrey; Nyflot, Matthew; Ford, Eric

    2016-09-01

    The pretreatment physics plan review is a standard tool for ensuring treatment quality. Studies have shown that the majority of errors in radiation oncology originate in treatment planning, which underscores the importance of the pretreatment physics plan review. This quality assurance measure is fundamentally important and central to the safety of patients and the quality of care that they receive. However, little is known about its effectiveness. The purpose of this study was to analyze reported incidents to quantify the effectiveness of the pretreatment physics plan review with the goal of improving it. This study analyzed 522 potentially severe or critical near-miss events within an institutional incident learning system collected over a three-year period. Of these 522 events, 356 originated at a workflow point that was prior to the pretreatment physics plan review. The remaining 166 events originated after the pretreatment physics plan review and were not considered in the study. The applicable 356 events were classified into one of the three categories: (1) events detected by the pretreatment physics plan review, (2) events not detected but "potentially detectable" by the physics review, and (3) events "not detectable" by the physics review. Potentially detectable events were further classified by which specific checks performed during the pretreatment physics plan review detected or could have detected the event. For these events, the associated specific check was also evaluated as to the possibility of automating that check given current data structures. For comparison, a similar analysis was carried out on 81 events from the international SAFRON radiation oncology incident learning system. Of the 356 applicable events from the institutional database, 180/356 (51%) were detected or could have been detected by the pretreatment physics plan review. Of these events, 125 actually passed through the physics review; however, only 38% (47/125) were actually

  17. The effectiveness of pretreatment physics plan review for detecting errors in radiation therapy

    International Nuclear Information System (INIS)

    Gopan, Olga; Zeng, Jing; Novak, Avrey; Nyflot, Matthew; Ford, Eric

    2016-01-01

    Purpose: The pretreatment physics plan review is a standard tool for ensuring treatment quality. Studies have shown that the majority of errors in radiation oncology originate in treatment planning, which underscores the importance of the pretreatment physics plan review. This quality assurance measure is fundamentally important and central to the safety of patients and the quality of care that they receive. However, little is known about its effectiveness. The purpose of this study was to analyze reported incidents to quantify the effectiveness of the pretreatment physics plan review with the goal of improving it. Methods: This study analyzed 522 potentially severe or critical near-miss events within an institutional incident learning system collected over a three-year period. Of these 522 events, 356 originated at a workflow point that was prior to the pretreatment physics plan review. The remaining 166 events originated after the pretreatment physics plan review and were not considered in the study. The applicable 356 events were classified into one of the three categories: (1) events detected by the pretreatment physics plan review, (2) events not detected but “potentially detectable” by the physics review, and (3) events “not detectable” by the physics review. Potentially detectable events were further classified by which specific checks performed during the pretreatment physics plan review detected or could have detected the event. For these events, the associated specific check was also evaluated as to the possibility of automating that check given current data structures. For comparison, a similar analysis was carried out on 81 events from the international SAFRON radiation oncology incident learning system. Results: Of the 356 applicable events from the institutional database, 180/356 (51%) were detected or could have been detected by the pretreatment physics plan review. Of these events, 125 actually passed through the physics review; however

  18. Inspection methods for physical protection Task III review of other agencies' physical security activities for research reactors

    International Nuclear Information System (INIS)

    In Task I of this project, the current Nuclear Regulatory Commission (NRC) position-on physical security practices and procedures at research reactors were reviewed. In the second task, a sampling of the physical security plans was presented and the three actual reactor sites described in the security plans were visited. The purpose of Task III is to review other agencies' physical security activities for research reactors. During this phase, the actions, procedures and policies of two domestic and two foreign agencies other than the NRC that relate to the research reactor community were examined. The agencies examined were: International Atomic Energy Agency; Canadian Atomic Energy Control Board; Department of Energy; and American Nuclear Insurers

  19. A review of the environmental behavior of uranium derived from depleted uranium alloy penetrators

    Energy Technology Data Exchange (ETDEWEB)

    Erikson, R.L.; Hostetler, C.J.; Divine, J.R.; Price, K.R.

    1990-01-01

    The use of depleted uranium (DU) penetrators as armor-piercing projectiles in the field results in the release of uranium into the environment. Elevated levels of uranium in the environment are of concern because of radioactivity and chemical toxicity. In addition to the direct contamination of the soil with uranium, the penetrators will also chemically react with rainwater and surface water. Uranium may be oxidized and leached into surface water or groundwater and may subsequently be transported. In this report, we review some of the factors affecting the oxidation of the DU metal and the factors influencing the leaching and mobility of uranium through surface water and groundwater pathways, and the uptake of uranium by plants growing in contaminated soils. 29 refs., 10 figs., 3 tabs.

  20. Reliability and Validity of Physical Activity Instruments Used in Children and Youth With Physical Disabilities: A Systematic Review.

    Science.gov (United States)

    White, Lauren; Volfson, Zlata; Faulkner, Guy; Arbour-Nicitopoulos, Kelly

    2016-05-01

    Research often characterizes children and youth with physical disabilities as less physically active than their typically developing peers. To inform the development and evaluation of future interventions, it is important to identify the most accurate methods for assessing physical activity behavior in this population. The objectives of this review were 1) to identify the self-report and objective instruments used to examine habitual physical activity behavior within this population and 2) to determine the reliability and validity of these instruments. Following a standardized protocol, a systematic review was conducted using six electronic databases and a range of search terms. Fifty studies (N = 2,613; Mage = 11.3 ± 2.6 years; 53% male) were included. Seven disability groups were examined, with the majority of studies focused on cerebral palsy (64%) and juvenile arthritis (20%). Poor to good reliability and weak validity were found among the self-report instruments such as questionnaires and activity diaries. Good to excellent reliability and validity were established for the objective instruments such as activity monitors (e.g., accelerometers, pedometers). Further research is warranted among physical disability groups other than cerebral palsy, and in establishing reliability and validity of self-report physical activity instruments specific to these target groups.

  1. Physical Activity Interventions With African American or Latino Men: A Systematic Review.

    Science.gov (United States)

    Griffith, Derek M; Bergner, Erin M; Cornish, Emily K; McQueen, Chelsea M

    2018-03-01

    Relatively little is known about what helps increase physical activity in African American men, and even less is known about promoting physical activity among Latino men. This systematic review aimed to address the key questions: (a) what is the state of the evidence on health-related behavior change interventions targeting physical activity among African American or Latino men? and (b) What factors facilitate physical activity for these men? For this review, nine electronic databases were searched to identify peer-reviewed articles published between 2011-2017 that reported interventions to promote physical activity among African American or Latino men. Following PRISMA guidelines, nine articles representing seven studies that met our criteria were identified: six published studies that provided data for African American men, and one published study provided data for Latino men. Consistent with previous reviews, more research is needed to better understand how gender can be incorporated in physical activity interventions for African American and Latino men. Future interventions should explore how being an adult male and a man of color shapes motivations, attitudes, and preferences to be physically active. Studies should consider how race and ethnicity intersect with notions of masculinity, manhood and Machismo to enhance the effectiveness of physical activity interventions for these populations. Despite the health benefits of physical activity, rates of these behaviors remain low among African American and Latino men. It is essential to determine how best to increase the motivation and salience for these men to overcome the obesogenic environments and contexts in which they often live.

  2. Physical activity and blood pressure. A cross-sectional review

    OpenAIRE

    Støyten, Martin

    2017-01-01

    Background: Hypertension is known as a major risk factor for cardiovascular disease, and the world-wide prevalence of hypertension is expected to rise to 30 % by the end of 2025. Physical activity has been shown to be a major part of the conservative treatment of hypertension, although the nature of the dose-response relationship is not known. The purpose of this study was to examine the associations between physical activity and blood pressure in the sixth survey of the Tromsø Study. Meth...

  3. Exercise therapy and other types of physical therapy for patients with neuromuscular diseases: a systematic review.

    NARCIS (Netherlands)

    Cup, E.H.C.; Pieterse, A.J.; Broek-Pastoor, J.M.C. ten; Munneke, M.; Engelen, B.G.M. van; Hendricks, H.T.; Wilt, G.J. van der; Oostendorp, R.A.B.

    2007-01-01

    OBJECTIVE: To summarize and critically appraise the available evidence on exercise therapy and other types of physical therapies for patients with neuromuscular diseases (NMD). DATA SOURCES: Cochrane Central Register of Controlled Trials and Cochrane Database of Systematic Reviews, Medline, CINAHL,

  4. Attitudes, barriers and enablers to physical activity in pregnant women: a systematic review

    Directory of Open Access Journals (Sweden)

    Anne L Harrison

    2018-01-01

    Registration: PROSPERO CRD42016037643. [Harrison AL, Taylor NF, Shields N, Frawley HC (2018 Attitudes, barriers and enablers to physical activity in pregnant women: a systematic review. Journal of Physiotherapy 64: 24–32

  5. Physical Examination Findings Among Children and Adolescents With Obesity: An Evidence-Based Review.

    Science.gov (United States)

    Armstrong, Sarah; Lazorick, Suzanne; Hampl, Sarah; Skelton, Joseph A; Wood, Charles; Collier, David; Perrin, Eliana M

    2016-02-01

    Overweight and obesity affects 1 in 3 US children and adolescents. Clinical recommendations have largely focused on screening guidelines and counseling strategies. However, the physical examination of the child or adolescent with obesity can provide the clinician with additional information to guide management decisions. This expert-based review focuses on physical examination findings specific to children and adolescents with obesity. For each physical examination element, the authors define the finding and its prevalence among pediatric patients with obesity, discuss the importance and relevance of the finding, describe known techniques to assess severity, and review evidence regarding the need for additional evaluation. The recommendations presented represent a comprehensive review of current evidence as well as expert opinion. The goal of this review is to highlight the importance of conducting a targeted physical examination during pediatric weight management visits. Copyright © 2016 by the American Academy of Pediatrics.

  6. PHYSICS

    CERN Multimedia

    J. Incandela

    The all-plenary format of the CMS week in Cyprus gave the opportunity to the conveners of the physics groups to present the plans of each physics analysis group for tackling early physics analyses. The presentations were complete, so all are encouraged to browse through them on the Web. There is a wealth of information on what is going on, by whom and on what basis and priority. The CMS week was followed by two CMS “physics events”, the ICHEP08 days and the physics days in July. These were two weeks dedicated to either the approval of all the results that would be presented at ICHEP08, or to the review of all the other Monte-Carlo based analyses that were carried out in the context of our preparations for analysis with the early LHC data (the so-called “2008 analyses”). All this was planned in the context of the beginning of a ramp down of these Monte Carlo efforts, in anticipation of data.  The ICHEP days are described below (agenda and talks at: http://indic...

  7. Promoting physical activity in rheumatoid arthritis: a narrative review of behaviour change theories.

    Science.gov (United States)

    Larkin, Louise; Kennedy, Norelee; Gallagher, Stephen

    2015-01-01

    Despite physical activity having significant health benefits for people with rheumatoid arthritis (RA), current levels of physical activity in this population are suboptimal. Changing behaviour is challenging and interventions aimed at increasing physical activity in this context have had varying levels of success. This review provides an overview of common behaviour change theories used in interventions to promote physical activity and their application for promoting physical activity in people with RA. A scoping, narrative review was conducted of English language literature, using the search terms "physical activity/exercise" and keywords, which are associated with behaviour change interventions. The theoretical basis of such interventions in people with RA was assessed using the "theory coding scheme". Six theories which have been used in physical activity research are discussed. Further, four studies which aimed to increase physical activity levels in people with RA are explored in detail. To date, behaviour change interventions conducted in RA populations to increase physical activity levels have not had a strong theoretical underpinning. It is proposed that an intervention utilising the theory of planned behaviour is developed with the aim of increasing physical activity in people with RA. Implications for Rehabilitation Interventions to promote physical activity in the rheumatoid arthritis (RA) population have failed to change participants' behaviour. A small number of studies have used behaviour change theories in the development and delivery of interventions. The theory of planned behaviour is recommended as the theoretical basis for an intervention to promote physical activity in the RA population.

  8. Physical activity level in pediatric population: A comprehensive review

    African Journals Online (AJOL)

    Physical activity (PA) is a key component in the maintenance and attainment of healthy, active, well-nourished and psycho-social well-being of a society. Hence, the reduction of sedentary lifestyle has featured in many countries as an important arm of policy designed to address childhood chronic diseases of lifestyle risk ...

  9. An integrative review: work environment factors associated with physical activity among white-collar workers.

    Science.gov (United States)

    Lin, Yun-Ping; McCullagh, Marjorie C; Kao, Tsui-Sui; Larson, Janet L

    2014-02-01

    The purpose of this review is to synthesize the research evidence for the role of the work environment-workplace physical activity policies and resources and job strain factors-in explaining physical activity in white-collar workers. White-collar workers are at risk for developing a sedentary lifestyle, which contributes to all-cause mortality. Understanding how work environment can influence worker physical activity is important for the development of effective interventions. We reviewed 15 research articles that describe the relationship between work environment factors and physical activity in predominantly white-collar workers. Relatively consistent evidence was found for the effects of supportive workplace policies and resources. Weak evidence was found for the effects of job strain. Both work environment factors have the potential to influence physical activity but require further exploration to fully understand their contribution to physical activity in white-collar workers. Limitations and implications are discussed.

  10. Exercise and physical training improve physical function in older adults with visual impairments but their effect on falls is unclear: a systematic review

    Directory of Open Access Journals (Sweden)

    Michael Gleeson

    2014-09-01

    [Gleeson M, Sherrington C, Keay L (2014 Exercise and physical training improve physical function in older adults with visual impairments but their effect on falls is unclear: a systematic review. Journal of Physiotherapy 60: 130–135

  11. Effectiveness and feasibility of early physical rehabilitation programs for geriatric hospitalized patients : a systematic review

    NARCIS (Netherlands)

    Kosse, Nienke M.; Dutmer, Alisa L.; Dasenbrock, Lena; Bauer, Juergen M.; Lamoth, Claudine J. C.

    2013-01-01

    Background: Old adults admitted to the hospital are at severe risk of functional loss during hospitalization. Early in-hospital physical rehabilitation programs appear to prevent functional loss in geriatric patients. The first aim of this review was to investigate the effect of early physical

  12. 75 FR 57298 - Proposal Review Panel for Physics; Notice of Meeting

    Science.gov (United States)

    2010-09-20

    ... report on progress of research performed under a Cooperative Agreement with the National Science... NATIONAL SCIENCE FOUNDATION Proposal Review Panel for Physics; Notice of Meeting In accordance... announces the following meeting. Name: University of Notre Dame Site Visit in Physics (1208). Date and Time...

  13. A systematic review - physical activity in dementia: The influence of the nursing home environment

    NARCIS (Netherlands)

    Anderiesen, H.; Scherder, E.J.A.; Goossens, R.H.; Sonneveld, M.

    2014-01-01

    Most older persons with dementia living in nursing homes spend their days without engaging in much physical activity. This study therefore looked at the influence that the environment has on their level of physical activity, by reviewing empirical studies that measured the effects of environmental

  14. Physical environmental stimuli that turn healthcare facilities into healing environments through psychologically mediated effects : Systematic review

    NARCIS (Netherlands)

    Dijkstra, Karin; Pieterse, Marcel E.; Pruyn, Ad

    2006-01-01

    Aim. This paper reports a systematic review to determine the effects of physical environmental stimuli in healthcare settings on the health and well-being of patients. Background. The concept of healing environments suggests that the physical environment of the healthcare setting can encourage the

  15. Management of physical child abuse in South Africa:Literature review and children's hospital data analysis

    NARCIS (Netherlands)

    Janssen, T.L. (T. L.); M. van Dijk (Monique); Al Malki, I. (I.); A.B. van As (Àrjan Bastiaan)

    2013-01-01

    textabstractBackground: The reason for this review is the lack of data on the management of physical abused children in Africa. The primary goal of the first part is to outline the management of physical child abuse in (South) Africa and provide suggestions for other governments in Africa on which

  16. 75 FR 70952 - Proposal Review Panel for Physics; Notice of Meeting

    Science.gov (United States)

    2010-11-19

    ... From the Federal Register Online via the Government Publishing Office NATIONAL SCIENCE FOUNDATION Proposal Review Panel for Physics; Notice of Meeting In accordance with the Federal Advisory Committee Act...: Partially Closed. Contact Person: Dr. Marvin Goldberg, Program Director for Elementary Particle Physics...

  17. A Systematic Review of Public Health-Aligned Recommendations for Preparing Physical Education Teacher Candidates

    Science.gov (United States)

    Webster, Collin A.; Webster, Liana; Russ, Laura; Molina, Sergio; Lee, Heesu; Cribbs, Jason

    2015-01-01

    Purpose: Since Sallis and McKenzie's seminal article in 1991 outlining physical education's role in public health, increased attention has been given to promoting youth physical activity in schools. The present study systematically reviewed the literature from 1991 to 2013 to identify recommendations for the preparation of physical…

  18. A narrative review of research on the effects of physical activity on ...

    African Journals Online (AJOL)

    The article explores different types and effects of physical activity for people living with HIV. Considering the lack of studies done in African contexts and the disparity between research settings and natural settings, a narrative review of the literature was conducted and contextualised to South Africa. Various physical ...

  19. Manual therapy with or without physical medicine modalities for neck pain: a systematic review

    NARCIS (Netherlands)

    D'Sylva, Jonathan; Miller, Jordan; Gross, Anita; Burnie, Stephen J.; Goldsmith, Charles H.; Graham, Nadine; Haines, Ted; Brønfort, Gert; Hoving, Jan L.

    2010-01-01

    Manual therapy interventions are often used with or without physical medicine modalities to treat neck pain. This review assessed the effect of 1) manipulation and mobilisation, 2) manipulation, mobilisation and soft tissue work, and 3) manual therapy with physical medicine modalities on pain,

  20. Factors of physical activity among Chinese children and adolescents : A systematic review

    NARCIS (Netherlands)

    Lu, Congchao; Stolk, Ronald P.; Sauer, Pieter J. J.; Sijtsma, Anna; Wiersma, Rikstje; Huang, Guowei; Corpeleijn, Eva

    2017-01-01

    Background: Lack of physical activity is a growing problem in China, due to the fast economic development and changing living environment over the past two decades. The aim of this review is to summarize the factors related to physical activity in Chinese children and adolescents during this

  1. A brief review on correlates of physical activity and sedentariness in youth.

    NARCIS (Netherlands)

    van der Horst, K.; Paw, M.J.; Twisk, J.W.R.; van Mechelen, W.

    2007-01-01

    INTRODUCTION: Better understanding of the correlates of physical activity and sedentary behaviors in youth will support the development of effective interventions that promote a physically active lifestyle and prevent a sedentary lifestyle. The main goal of this systematic review is to summarize and

  2. The Educational Benefits Claimed for Physical Education and School Sport: An Academic Review

    Science.gov (United States)

    Bailey, Richard; Armour, Kathleen; Kirk, David; Jess, Mike; Pickup, Ian; Sandford, Rachel

    2009-01-01

    This academic review critically examines the theoretical and empirical bases of claims made for the educational benefits of physical education and school sport (PESS). An historical overview of the development of PESS points to the origins of claims made in four broad domains: physical, social, affective and cognitive. Analysis of the evidence…

  3. Utility of Acculturation in Physical Activity Research in Latina Adults: An Integrative Review of Literature

    Science.gov (United States)

    Benitez, Tanya J.; Dodgson, Joan E.; Coe, Kathryn; Keller, Colleen

    2016-01-01

    Latina adults in the United States have a disproportionately higher prevalence of chronic diseases related to low physical activity levels than non-Hispanic women. Literature indicates that acculturation may be a contributing factor to being physically active, but the extent of this association remains unclear. An integrative review of literature…

  4. Impact of physical therapy for Parkinson's disease : A critical review of the literature

    NARCIS (Netherlands)

    Kwakkel, G.; de Goede, C. J T; van Wegen, E. E H

    2007-01-01

    A systematic review of the literature found 23 randomized clinical trials reflecting specific core areas of physical therapy (PT), that is, transfer, posture, balance, reaching and grasping, gait, and physical condition. All studies were of moderate methodological quality. Important limitations of

  5. Physics-based simulation modeling and optimization of microstructural changes induced by machining and selective laser melting processes in titanium and nickel based alloys

    Science.gov (United States)

    Arisoy, Yigit Muzaffer

    Manufacturing processes may significantly affect the quality of resultant surfaces and structural integrity of the metal end products. Controlling manufacturing process induced changes to the product's surface integrity may improve the fatigue life and overall reliability of the end product. The goal of this study is to model the phenomena that result in microstructural alterations and improve the surface integrity of the manufactured parts by utilizing physics-based process simulations and other computational methods. Two different (both conventional and advanced) manufacturing processes; i.e. machining of Titanium and Nickel-based alloys and selective laser melting of Nickel-based powder alloys are studied. 3D Finite Element (FE) process simulations are developed and experimental data that validates these process simulation models are generated to compare against predictions. Computational process modeling and optimization have been performed for machining induced microstructure that includes; i) predicting recrystallization and grain size using FE simulations and the Johnson-Mehl-Avrami-Kolmogorov (JMAK) model, ii) predicting microhardness using non-linear regression models and the Random Forests method, and iii) multi-objective machining optimization for minimizing microstructural changes. Experimental analysis and computational process modeling of selective laser melting have been also conducted including; i) microstructural analysis of grain sizes and growth directions using SEM imaging and machine learning algorithms, ii) analysis of thermal imaging for spattering, heating/cooling rates and meltpool size, iii) predicting thermal field, meltpool size, and growth directions via thermal gradients using 3D FE simulations, iv) predicting localized solidification using the Phase Field method. These computational process models and predictive models, once utilized by industry to optimize process parameters, have the ultimate potential to improve performance of

  6. Touch for Socioemotional and Physical Well-Being: A Review

    Science.gov (United States)

    Field, Tiffany

    2010-01-01

    This review briefly summarizes recent empirical research on touch. The research includes the role of touch in early development, touch deprivation, touch aversion, emotions that can be conveyed by touch, the importance of touch for interpersonal relationships and how friendly touch affects compliance in different situations. MRI data are reviewed…

  7. Review of e+e--physics with PETRA

    International Nuclear Information System (INIS)

    Lohrmann, E.

    1983-10-01

    The author reviews the most recent experiments at PETRA. These concern studies of toponium, magnetic monopoles, excited leptons, supersymmetric particles, lepton pair production as test of the standard model, branching ratios for the decays of the tau and heavy quarks, and studies of inclusive hadron production. (HSI)

  8. Physical methods for initiation of emulsion polymerization processes (review)

    International Nuclear Information System (INIS)

    Averko-Antonovich, I.Yu.; Liakumovich, A.G.

    1994-01-01

    The known and widely used methods for initiation of emulsion polymerization by the exposure of aqueous and organic media to ionizing radiation, plasmoichemical, mechanochemcial, and magnetic treatments, are briefly reviewed. The advantages of radiation-induced emulsion polymerization of vinyl monomers, as compared to the other methods, are pointed out

  9. Physical fitness in people with posttraumatic stress disorder: a systematic review.

    Science.gov (United States)

    Vancampfort, Davy; Stubbs, Brendon; Richards, Justin; Ward, Philip B; Firth, Joseph; Schuch, Felipe B; Rosenbaum, Simon

    2017-12-01

    People with posttraumatic stress disorder (PTSD) have an increased risk of cardiovascular diseases (CVD). Physical fitness is a key modifiable risk factor for CVD and associated mortality. We reviewed the evidence-base regarding physical fitness in people with PTSD. Two independent reviewers searched PubMed, CINAHL, PsycARTICLES, PEDro, and SPORTDiscus from inception until May 2016 using the key words "fitness" OR "exercise" AND "posttraumatic stress disorder" OR "PTSD". In total, 5 studies involving 192 (44 female) individuals with PTSD met the inclusion criteria. Lower baseline physical fitness are associated with greater reductions in avoidance and hyperarousal symptoms, as well as with total, physical, and social symptoms of anxiety sensitivity. Rigorous data comparing physical fitness with age- and gender matched general population controls are currently lacking. The research field regarding physical fitness in people with PTSD is still in its infancy. Given the established relationships between physical fitness, morbidity and mortality in the general population and the current gaps in the PTSD literature, targets for future research include exploring: (a) whether people with PTSD are at risk of low physical fitness and therefore in need of intensified assessment, treatment and follow-up, (b) the relationships among physical fitness, overall health status, chronic disease risk reduction, disability, and mortality in individuals PTSD, (c) psychometric properties of submaximal physical fitness tests in PTSD, (d) physical fitness changes following physical activity in PTSD, and (e) optimal methods of integrating physical activity programs within current treatment models for PTSD. Implications for Rehabilitation People with PTSD should aim to achieve 150 minutes of moderate or 75 minutes vigorous physical activity per week while also engaging in resistance training exercises at least twice a week. Health care professionals should assist people with PTSD to

  10. How might we increase physical activity through dog walking?: A comprehensive review of dog walking correlates

    OpenAIRE

    Westgarth, Carri; Christley, Robert M; Christian, Hayley E

    2014-01-01

    Background Physical inactivity and sedentary behaviour are major threats to population health. A considerable proportion of people own dogs, and there is good evidence that dog ownership is associated with higher levels of physical activity. However not all owners walk their dogs regularly. This paper comprehensively reviews the evidence for correlates of dog walking so that effective interventions may be designed to increase the physical activity of dog owners. Methods Published findings fro...

  11. SIFAT FISIK, KIMIA, DAN FUNGSIONAL DAMAR [Brief Review on: Physical, Chemical and Functional Properties of Dammar

    OpenAIRE

    Noryawati Mulyono1); Anton Apriyantono2)

    2004-01-01

    Dammar is one of Indonesian forestry products which is abundant. It has unique physical, chemical and functional properties. The important physical properties of dammar include its solubility in some organic solvents, softening temperature, viscosity and its absorbance. The important chemical properties reviewed here include its properties as resin, composition of terpenoid compounds present in dammar, and essential oil yielded from distillation of fresh dammar. Physical and chemical properti...

  12. Childhood socioeconomic position and adult leisure-time physical activity: a systematic review protocol

    OpenAIRE

    Elhakeem, A.; Cooper, R.; Bann, D. A.; Hardy, R.

    2014-01-01

    Background Participation in leisure-time physical activity benefits health and is thought to be more prevalent in higher socioeconomic groups. Evidence indicates that childhood socioeconomic circumstances may have long-term influences on adult health and behaviour; however, it is unclear if this extends to an influence on adult physical activity. The aim of this review is to examine whether a lower childhood socioeconomic position is associated with lower levels of leisure-time physical activ...

  13. Friendship networks and physical activity and sedentary behavior among youth: a systematized review.

    Science.gov (United States)

    Sawka, Keri Jo; McCormack, Gavin R; Nettel-Aguirre, Alberto; Hawe, Penelope; Doyle-Baker, Patricia K

    2013-12-01

    Low levels of physical activity and increased participation in sedentary leisure-time activities are two important obesity-risk behaviors that impact the health of today's youth. Friend's health behaviors have been shown to influence individual health behaviors; however, current evidence on the specific role of friendship networks in relation to levels of physical activity and sedentary behavior is limited. The purpose of this review was to summarize evidence on friendship networks and both physical activity and sedentary behavior among children and adolescents. After a search of seven scientific databases and reference scans, a total of thirteen articles were eligible for inclusion. All assessed the association between friendship networks and physical activity, while three also assessed sedentary behavior. Overall, higher levels of physical activity among friends are associated with higher levels of physical activity of the individual. Longitudinal studies reveal that an individual's level of physical activity changes to reflect his/her friends' higher level of physical activity. Boys tend to be influenced by their friendship network to a greater extent than girls. There is mixed evidence surrounding a friend's sedentary behavior and individual sedentary behavior. Friends' physical activity level appears to have a significant influence on individual's physical activity level. Evidence surrounding sedentary behavior is limited and mixed. Results from this review could inform effective public health interventions that harness the influence of friends to increase physical activity levels among children and adolescents.

  14. Review on study of multi-physics in environment engineering

    International Nuclear Information System (INIS)

    Liu Shanli; Zhao Jian; Sheng Jinchang

    2006-01-01

    This paper analyzes some problems on multi-field coupling ones between seepage mechanics and other physical and chemical processes (such as temperature field. stress field, solute transport. chemical action and so on) in environment engineering, it explains the research theory of multi-field coupling, it summarizes the abroad and domestic research about the model of multi-field problem and finally it looks into the future of research tendency in environment engineering. (authors)

  15. Field : Sport Sciences, Physical Education Type : Review Article

    OpenAIRE

    MUNAFO, Carmelo

    2016-01-01

    The purpose of this article was to explore Cooperative Learning as a promising approach for the inclusion of students with disabilities in physical education (Moliterni, 2013; de Anna, 2009; Cervantes et al. 2007). Constructivist perspective is used as a theoretical framework and connection with Cooperative Learning. Research in America by Johnson & Johnson (1989) on the use and benefit of Cooperative Learning in the classroom environment have been conducted, but we are now beginning ...

  16. 1984 Review of the Applied Plasma Physics Program

    International Nuclear Information System (INIS)

    1984-09-01

    This report describes the present and planned programs of the Division of Applied Plasma Physics (APP), Office of Fusion Energy. The major activities of the division include fusion theory, experimental plasma research, advanced fusion concepts, and the magnetic fusion energy computer network. The planned APP program is consistent with the recently issued Comprehensive Program Management Plan for Magnetic Fusion Energy, which describes the overall objectives and strategy for the development of fusion energy

  17. Adolescents' perspectives on the barriers and facilitators of physical activity: a systematic review of qualitative studies.

    Science.gov (United States)

    Martins, João; Marques, Adilson; Sarmento, Hugo; Carreiro da Costa, Francisco

    2015-10-01

    This article examined qualitative studies of adolescents' perspectives about the facilitators and barriers of physical activity, published from 2007 to 2014. A systematic review of 'Web of Science', 'EBSCO', 'Psychinfo' and 'ERIC' databases was performed according to Preferred Reporting Items for Systematic reviews and Meta-analyses guidelines. The following keywords were used: 'physical activity' and 'physical education', each one individually associated with 'correlate', 'determinant', 'facilitator', 'barrier', 'factor influen*', and with 'qualitative', 'focus group', 'interview', "narrative'. Out of 3815 studies initially identified, due to inclusion and quality criteria, only 12 were fully reviewed. Studies' outcomes were analyzed through thematic analysis. The majority of these reported research with young adolescent girls. Few studies have considered the socioeconomic status influence. According to young people's perspectives, the main facilitators and hampering factors to their participation in physical activity were the following: attitude toward physical activity; motivation; perceptions of competence and body image; fun; influence of friends, family and physical education teachers and environmental physical activity opportunities. Specific life transition periods were referred only as a barrier to physical activity. Strategies of pedagogical actions and for developing physical activity intervention programs were discussed, in order to effectively promote the adoption of active lifestyles among youth. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  18. Curricular Space Allocated for Dance Content in Physical Education Teacher Education Programs: A Literature Review

    Science.gov (United States)

    Marquis, Jenée Marie; Metzler, Mike

    2017-01-01

    This literature review examines curricular space allocated to activity based/movement content courses in Physical Education Teacher Education (PETE) pre-service programs, specifically focusing on how dance content knowledge and pedagogical content knowledge are addressed within those programs. This review includes original empirical research…

  19. Educational Functioning of Children of Parents with Chronic Physical Illness: A Systematic Review

    Science.gov (United States)

    Chen, Cliff Yung-Chi

    2016-01-01

    A systematic review of the literature was performed to answer the question: What are the effects of parental chronic physical illness on children's educational functioning? Thirteen studies that met the inclusion criteria for the purpose of this review were identified, indicating the paucity of research on the topic. The results found that…

  20. Critical literature review of relationships between processing parameters and physical properties of particleboard

    Science.gov (United States)

    Myron W. Kelly

    1977-01-01

    The pertinent literature has been reviewed, and the apparent effects of selected processing parameters on the resultant particleboard properties, as generally reported in the literature, have been determined. Resin efficiency, type and level, furnish, and pressing conditions are reviewed for their reported effects on physical, strength, and moisture and dimensional...

  1. A Systematic Review of Universal Campaigns Targeting Child Physical Abuse Prevention

    Science.gov (United States)

    Poole, Mary Kathryn; Seal, David W.; Taylor, Catherine A.

    2014-01-01

    The purpose of this review was to better understand the impact of universal campaign interventions with a media component aimed at preventing child physical abuse (CPA). The review included 17 studies featuring 15 campaigns conducted from 1989 to 2011 in five countries. Seven studies used experimental designs, but most were quasi-experimental. CPA…

  2. Review of diagnostic tools to investigate the physical state of rapid granular filters

    DEFF Research Database (Denmark)

    Lopato, Laure Rose; Binning, Philip John; Arvin, Erik

    2012-01-01

    This paper reviews diagnostic tools that can be used at waterworks to investigate the physical and operational state of rapid granular filters. Diagnostic tools can be of interest for the Water Safety Plans of WHO to monitor filters in a proactive manner. The review considers conventional and state...

  3. Social Marketing Interventions Aiming to Increase Physical Activity among Adults: A Systematic Review

    Science.gov (United States)

    Kubacki, Krzysztof; Ronti, Rimante; Lahtinen, Ville; Pang, Bo; Rundle-Thiele, Sharyn

    2017-01-01

    Purpose: A significant proportion of the world's adult population is insufficiently active. One approach used to overcome barriers and facilitate participation in physical activity is social marketing. The purpose of this paper are twofold: first, this review seeks to provide a contemporary review of social marketing's effectiveness in changing…

  4. Parenting Practices and Children's Physical Activity: An Integrative Review

    Science.gov (United States)

    Hutchens, Amy; Lee, Rebecca E.

    2018-01-01

    The purpose of this integrative review was to analyze the state of science concerning the influence of parenting practices on children's physical activity (PA) levels. A total of 38 studies met the inclusion criteria after full-text review. The body of research is limited in experimental designs with only three studies measuring the influence of…

  5. Calcium metal as a scavenger for antimony from aluminum alloys

    Energy Technology Data Exchange (ETDEWEB)

    Bonsignore, P.V.; Daniels, E.J.; Wu, C.T.

    1994-10-04

    Previous work has shown that trace amounts of antimony (Sb) can affect the mechanical properties of strontium (Sr) modified aluminum castings. ANL has been investigating technology to remove or neutralize Sb to reduce its negative effect on the physical properties of those alloys. Review of past work on processing and recovery of scrap aluminum inferred that calcium (Ca) is an effective scavenger of Sb, bismuth, lead and cadmium. Following up on that lead, we have found that Ca is, indeed, effective for removing Sb from molten aluminum alloys although its effectiveness can be compromised by a wide range of processing conditions. A minimum ratio of about four to one, by weight, of Ca to Sb appears necessary to insure an effective scavenging of contained Sb.in 356 aluminum alloys.

  6. The many Metaphysics within Physics. Essay review of 'The Metaphysics within Physics' by Tim Maudlin

    Science.gov (United States)

    Suárez, Mauricio

    Tim Maudlin's new book The Metaphysics within Physics (Oxford University Press, 2007) collects six essays by one of the most thoughtful and original minds working in the philosophy of physics nowadays. Some had previously circulated informally for years. For example, Chapter 1 ('A Modest Proposal Concerning Laws, Counterfactuals and Explanations') is as old as my own philosophical career-I recall reading a draft in the early 1990s. The mere publication of such a long-awaited collection is therefore already good news. In addition, the degree of coherence and the lack of redundancy are greater than one would expect from a collection of disparate essays written at diverse times and with a range of different targets. The whole book can be understood coherently as an extended argument in favor of a particular 'physics-based' methodology for inquiry in metaphysics. This methodology recommends a detailed and thorough analysis of current physics as a benchmark for any thesis, dispute or argument in metaphysics. It follows that proper metaphysical inquiry must be suitably informed not just about the current state of play in analytical metaphysics but also about the current state of development of the relevant part of present day physics.

  7. How Games are Designed to Increase Students’ Motivation in Learning Physics? A Literature Review

    Science.gov (United States)

    Tinedi, V.; Yohandri, Y.; Djamas, D.

    2018-04-01

    Game is a promising tool to help students in understanding physics concept. It can motivate and provide the opportunities for students to become independent in learning. In order to fulfil these functions, games should be carefully designed. Thus, the objective of this paper is to present how games are designed to increase students’ motivation in learning physics based on several literature reviews. The results showed that there are several ways to increase students’ motivation in learning physics and to achieve that, game dimensions are needed to be considered when designing a game. This literature review may have useful to assist teachers and contribute in improving the design of games.

  8. A first-principles thermodynamic approach to ordering in binary alloys

    Indian Academy of Sciences (India)

    Unknown

    **Department of Physics, Indian Institute of Technology, Powai, Mumbai 400 076, India. †Materials Science Division, #TP&PE Division, Bhabha Atomic Research Centre, Mumbai 400 085, India. Abstract. The communication reviews the augmented space based approaches to thermodynamics and ordering of binary alloys.

  9. What Is the Relationship between Outdoor Time and Physical Activity, Sedentary Behaviour, and Physical Fitness in Children? A Systematic Review

    Directory of Open Access Journals (Sweden)

    Casey Gray

    2015-06-01

    Full Text Available The objective of this systematic review was to examine the relationship between outdoor time and: (1 physical activity, (2 cardiorespiratory fitness, (3 musculoskeletal fitness, (4 sedentary behaviour; or (5 motor skill development in children aged 3–12 years. We identified 28 relevant studies that were assessed for quality using the GRADE framework. The systematic review revealed overall positive effects of outdoor time on physical activity, sedentary behaviour, and cardiorespiratory fitness, although causality could not be assumed due to a lack of RCTs. Motor skill development was unrelated to outdoor time; however, this relationship was only examined in a single study of preschool children. No studies were found that examined associations between outdoor time and musculoskeletal fitness.

  10. What Is the Relationship between Outdoor Time and Physical Activity, Sedentary Behaviour, and Physical Fitness in Children? A Systematic Review

    Science.gov (United States)

    Gray, Casey; Gibbons, Rebecca; Larouche, Richard; Sandseter, Ellen Beate Hansen; Bienenstock, Adam; Brussoni, Mariana; Chabot, Guylaine; Herrington, Susan; Janssen, Ian; Pickett, William; Power, Marlene; Stanger, Nick; Sampson, Margaret; Tremblay, Mark S.

    2015-01-01

    The objective of this systematic review was to examine the relationship between outdoor time and: (1) physical activity, (2) cardiorespiratory fitness, (3) musculoskeletal fitness, (4) sedentary behaviour; or (5) motor skill development in children aged 3–12 years. We identified 28 relevant studies that were assessed for quality using the GRADE framework. The systematic review revealed overall positive effects of outdoor time on physical activity, sedentary behaviour, and cardiorespiratory fitness, although causality could not be assumed due to a lack of RCTs. Motor skill development was unrelated to outdoor time; however, this relationship was only examined in a single study of preschool children. No studies were found that examined associations between outdoor time and musculoskeletal fitness. PMID:26062039

  11. Relationship between the physical environment and different domains of physical activity in European adults: a systematic review

    Directory of Open Access Journals (Sweden)

    Van Holle Veerle

    2012-09-01

    Full Text Available Abstract Background In the past decade, various reviews described the relationship between the physical environment and different physical activity (PA domains. Yet, the majority of the current review evidence relies on North American/Australian studies, while only a small proportion of findings refer to European studies. Given some clear environmental differences across continents, this raises questions about the applicability of those results in European settings. This systematic review aimed at summarizing Europe-specific evidence on the relationship between the physical environment and different PA domains in adults. Methods Seventy eligible papers were identified through systematic searches across six electronic databases. Included papers were observational studies assessing the relationship between several aspects of the physical environment and PA in European adults (18-65y. Summary scores were calculated to express the strength of the relationship between each environmental factor and different PA domains. Results Convincing evidence on positive relationships with several PA domains was found for following environmental factors: walkability, access to shops/services/work and the composite factor environmental quality. Convincing evidence considering urbanization degree showed contradictory results, dependent on the observed PA domain. Transportation PA was more frequently related to the physical environment than recreational PA. Possible evidence for a positive relationship with transportation PA emerged for walking/cycling facilities, while a negative relationship was found for hilliness. Some environmental factors, such as access to recreational facilities, aesthetics, traffic- and crime-related safety were unrelated to different PA domains in Europe. Conclusions Generally, findings from this review of European studies are in accordance with results from North American/Australian reviews and may contribute to a generalization of the

  12. A REVIEW ON COMPREHENSIVE EYE EXAMINATION IN PEDIATRIC PHYSICAL THERAPY

    Directory of Open Access Journals (Sweden)

    Rahul Pandey

    2015-12-01

    Full Text Available Background: Even early in Eye disease, children have reduced economy of activity of daily living. Early eye examination, diagnosis and management will reduce the consequences of other system originated by eye problems. The current literature is aimed to provide and explore the knowledge of Pediatric Physical Therapist about pediatric eye examination. This will help in early detection of any eye disorder and in good prognosis of visual health, physical growth, social and mental health as well. Methods: The data and contents of current literature have been explored from different webpages, books and by personnel experience in pediatric physical therapy and optometry. Results: In the beginning disclosure and immediate treatment of ocular diseases in children is necessary to prevent lifelong visual deterioration. Checkup of the eyes should be carrying out early in the neonates period and at all well-child visits. Neonates should be checked for ocular structural abnormalities, such as cataract, corneal opacity, and ptosis, which are known to cause in visual problems. Every child who are bring into being have an ocular anomaly or who fail vision examination should be referred to a pediatric ophthalmologist or an eye care specialist appropriately trained to treat pediatric patients. Conclusions: Children account for a large and growing percentage of the population of the India. Studies have demonstrated that the prevalence of eye and vision disorders is substantial in this group. Researches also reveal that early detection and intervention are particularly important in children because of the very quick development of the visual system in early childhood and its sensitivity to interference. When disorders such as amblyopia and squint are undetected, the long-term consequences can be serious in terms of quality of life, comfort, appearance, and career opportunities.

  13. Rationale for promoting physical activity among cancer survivors: literature review and epidemiologic examination.

    Science.gov (United States)

    Loprinzi, Paul D; Lee, Hyo

    2014-03-01

    To review the extant literature on the link between physical activity and health outcomes among cancer survivors; identify evidence-based strategies to promote physical activity among this population; and conduct an epidemiologic study based on gaps from the literature review, examining the association between physical activity and various biologic markers. The authors used PubMed and Google Scholar up to July 2013, as well as data from the 2003-2006 National Health and Nutrition Examination Survey for the empirical study. Studies were examined through a systematic review process. In the epidemiologic study, 227 adult cancer survivors wore an accelerometer for four days or longer, with biologic markers (e.g., cholesterol) assessed from a blood sample. The review study demonstrated that cancer survivors are relatively inactive, but physical activity may help to reduce the risk of cancer recurrence and cancer-related mortality, increase cancer treatment rates, reduce pain and other side effects associated with cancer treatment, and improve physical and mental health. The epidemiologic study showed that physical activity was associated with several understudied biomarkers (e.g., neutrophils, white blood cells) that are linked with cancer recurrence, cancer-related mortality, and other chronic diseases. Nurses are encouraged to promote physical activity in cancer survivors.

  14. BONE GEOMETRY AND PHYSICAL ACTIVITY IN CHILDREN AND ADOLESCENTS: SYSTEMATIC REVIEW.

    Science.gov (United States)

    Krahenbühl, Tathyane; Guimarães, Roseane de Fátima; Barros Filho, Antonio de Azevedo; Gonçalves, Ezequiel Moreira

    2018-01-15

    To perform a systematic review on the practice of physical activity and/or sports in health and its influence on bone geometry of healthy children and adolescents. The method used as reference was the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Databases searched for articles published from 2006 to 2016, with "Bone geometry" AND (Sport* OR Exercise* OR "Physical Activity") as descriptors, were PubMed, BIREME/LILACS and SciELO. After the selection, 21 articles were included. Most studies stated that practice of physical activity and/or sports was beneficial for bone geometry and bone mineral density. Only two studies presented values of bone parameters for control individuals better than those of swimmers. Physical activities and sports studied were: gymnastics (n=7), rhythmic gymnastics (n=2), tennis (n=1), soccer (n=3), capoeira (n=1), swimming (n=4), cycling (n=0), jumping activities (n=2), studies relating physical activity with isokinetic peak torque (n=1), physical activity measured by questionnaire (n=4), and additional physical education classes (n=2). Among the sports and physical activities found, gymnastics, soccer, and more intense physical activity assessed by questionnaires were mentioned along with better results in bone geometry compared to the absence of physical activity, whereas swimming and jumping exercises did not influence it. Therefore, sports activities with weight bearing and those practiced more frequently and intensively are beneficial for bone geometry.

  15. Evaluation of the Association between Physical Health and Religion: A Literature Review

    Directory of Open Access Journals (Sweden)

    Mohammad Taghi Karimi

    2014-03-01

    Full Text Available Physical health is influenced by various factors including religion. There are many questions regarding the impact of religious activities on physical health. Therefore, the aim of this study was to find the correlation between physical health and religion. Various databases including PubMed, Ovid, and Medline were investigated. Considering the inclusion criteria, 50 studies were found using the keyword-based information retrieval; though, only 12 papers were approved for the final analysis. Based on the literature review, there is no consensus regarding the impacts of religious practices on physical health; it is not clear whether religious activities result in better physical health and less severe musculoskeletal disorders, or are inversely related to physical health. There are various limitations observed in the available studies; therefore, reaching a firm conclusion might be no easy task. It is recommended that cross-sectional studies be carried out in various regions to find the association between religion and physical health

  16. Novel Dilute Bismide, Epitaxy, Physical Properties and Device Application

    Directory of Open Access Journals (Sweden)

    Lijuan Wang

    2017-02-01

    Full Text Available Dilute bismide in which a small amount of bismuth is incorporated to host III-Vs is the least studied III-V compound semiconductor and has received steadily increasing attention since 2000. In this paper, we review theoretical predictions of physical properties of bismide alloys, epitaxial growth of bismide thin films and nanostructures, surface, structural, electric, transport and optic properties of various binaries and bismide alloys, and device applications.

  17. 'Measuring' Physical Literacy and Related Constructs: A Systematic Review of Empirical Findings.

    Science.gov (United States)

    Edwards, Lowri C; Bryant, Anna S; Keegan, Richard J; Morgan, Kevin; Cooper, Stephen-Mark; Jones, Anwen M

    2018-03-01

    The concept of physical literacy has received increased research and international attention recently. Where intervention programs and empirical research are gaining momentum, their operationalizations differ significantly. The objective of this study was to inform practice in the measure/assessment of physical literacy via a systematic review of research that has assessed physical literacy (up to 14 June, 2017). Five databases were searched using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses for Protocols guidelines, with 32 published articles meeting the inclusion criteria. English-language, peer-reviewed published papers containing empirical studies of physical literacy were analyzed using inductive thematic analysis. Qualitative methods included: (1) interviews; (2) open-ended questionnaires; (3) reflective diaries; (4) focus groups; (5) participant observations; and (6) visual methods. Quantitative methods included: (1) monitoring devices (e.g., accelerometers); (2) observations (e.g., of physical activity or motor proficiency); (3) psychometrics (e.g., enjoyment, self-perceptions); (4) performance measures (e.g., exergaming, objective times/distances); (5) anthropometric measurements; and (6) one compound measure. Of the measures that made an explicit distinction: 22 (61%) examined the physical domain, eight (22%) the affective domain; five (14%) the cognitive domain; and one (3%) combined three domains (physical, affective, and cognitive) of physical literacy. Researchers tended to declare their philosophical standpoint significantly more in qualitative research compared with quantitative research. Current research adopts diverse often incompatible methodologies in measuring/assessing physical literacy. Our analysis revealed that by adopting simplistic and linear methods, physical literacy cannot be measured/assessed in a traditional/conventional sense. Therefore, we recommend that researchers are more creative in developing

  18. Physical activity, sedentary behavior and their correlates in children with Autism Spectrum Disorder: A systematic review.

    Science.gov (United States)

    Jones, Rachel A; Downing, Katherine; Rinehart, Nicole J; Barnett, Lisa M; May, Tamara; McGillivray, Jane A; Papadopoulos, Nicole V; Skouteris, Helen; Timperio, Anna; Hinkley, Trina

    2017-01-01

    Autism Spectrum Disorder affects up to 2.5% of children and is associated with harmful health outcomes (e.g. obesity). Low levels of physical activity and high levels of sedentary behaviors may contribute to harmful health outcomes. To systematically review the prevalence and correlates of physical activity and sedentary behaviors in children with Autism Spectrum Disorder, electronic databases (PsycINFO, SPORTDiscus, EMBASE, Medline) were searched from inception to November 2015. The review was registered with PROSPERO (CRD42014013849). Peer-reviewed, English language studies were included. Two reviewers screened potentially relevant articles. Outcomes of interest were physical activity and sedentary behaviour levels and their potential correlates. Data were collected and analysed in 2015. Of 35 included studies, 15 reported physical activity prevalence, 10 reported physical activity correlates, 18 reported sedentary behavior prevalence, and 10 reported sedentary behavior correlates. Estimates of children's physical activity (34-166 mins/day, average 86 mins/day) and sedentary behavior (126-558 mins/day in screen time, average 271 mins/day; 428-750 mins/day in total sedentary behavior, average 479 mins/day) varied across studies. Age was consistently inversely associated, and sex inconsistently associated with physical activity. Age and sex were inconsistently associated with sedentary behavior. Sample sizes were small. All but one of the studies were classified as having high risk of bias. Few correlates have been reported in sufficient studies to provide overall estimates of associations. Potential correlates in the physical environment remain largely unexamined. This review highlights varying levels of physical activity and sedentary behavior in children with Autism Spectrum Disorder. Research is needed to consistently identify the correlates of these behaviors. There is a critical need for interventions to support healthy levels of these behaviors.

  19. Physical activity in Brazil: lessons from ELSA-Brasil. Narrative review.

    Science.gov (United States)

    Pitanga, Francisco José Gondim; Almeida, Maria Conceição Chagas; Queiroz, Ciro Oliveira; Aquino, Estela Maria Leão de; Matos, Sheila Maria Alvim

    2017-01-01

    The Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) was conducted among civil servants at six higher education institutions located in six Brazilian state capitals. The objective of this review was to identify the publications produced within the scope of ELSA-Brasil that analyzed the participants' physical activity. Review study using baseline data from ELSA-Brasil. Narrative review of Brazilian studies on physical activity produced using data from ELSA-Brasil participants. The prevalence of leisure-time physical activity (LTPA) among ELSA-Brasil participants was low (44.1% among men and 33.8% among women). The main factors associated were social (higher schooling and family income), environmental (living in places with conditions and opportunities for physical activity) and individual (not being obese, being retired, not smoking and positive perception of body image). The perception of facilities for walking in the neighborhood was positively associated with both LTPA and commuting-related physical activity. An active lifestyle was a protective factor against several cardiometa-bolic variables (hypertension, diabetes, lipid abnormalities and cardiovascular risk over the next 10 years). Comparison between LTPA and commuting-related physical activity showed that only LTPA had a protective effect against arterial hypertension. The prevalence of physical activity among ELSA-Brasil participants was low. The main determinants were social, environmental and personal. LTPA had a greater protective efect on cardio-metabolic outcomes than did commuting-related physical activity.

  20. Physical activity in type II Diabetes Mellitus, an effective therapeutic element: review of the clinical impact

    Directory of Open Access Journals (Sweden)

    Pedro Iván Arias-Vázquez

    2015-07-01

    Full Text Available A review was conducted in databases (PubMed, PEDro of type studies clinical trial, cohort study, systematic reviews, meta-analysis and clinical practice guidelines based on evidence they have studied the benefits of physical activity in the prevention , treatment and decreased risk of complications and death in patients with Type II Diabetes Mellitus. Realization regular physical activity is associated with a decreased risk of developing Diabetes Mellitus; likewise was associated with decrease in glycated hemoglobin percentage A1C values. Diabetic patients undergoing high levels of physical activity had decreased risk of complications and death from cardiovascular disease and all causes. At present the scientific evidence on the impact of physical activity in the prevention and treatment of Diabetes Mellitus is solid, so it must be emphasized promoting physical activity as a fundamental part of the therapeutic regimens for this disease.

  1. Injury risk during different physical activity behaviours in children: a systematic review with bias assessment.

    Science.gov (United States)

    Nauta, Joske; Martin-Diener, Eva; Martin, Brian W; van Mechelen, Willem; Verhagen, Evert

    2015-03-01

    The current focus on a physically active lifestyle in children puts children at increased physical activity-related injury risk. To summarise, in a systematic review, the evidence for the injury risk of several physical activity behaviours in 6- to 12-year-old children. An electronic search was performed in three databases (Embase, PubMed and SPORTDiscus). Inclusion criteria were: age 6-12 years; report on injuries related to overall physical activity, active commuting, unorganised leisure time physical activity, physical education and/or organised sports; incidence rates expressed as injuries per hours of physical activity; and published after January 1st 2000. Risk of bias was assessed for all studies included. Eight studies were included. The risk of bias assessment resulted in two studies with a score that was higher than 75 %; risk bias of those two studies was considered low. The medically treated, injury incidence rate was reported to be between 0.15 and 0.27 injuries per 1,000 h of physical activity. The absolute number of injuries related to unorganised leisure time physical activity was higher than the absolute number of injuries reported in organised sports. The respective injury incidence rate expressed per 1,000 h exposure was, however, generally lower during unorganised leisure time than during organised sports. Reported injury incidence rates related to active commuting were comparable to those for unorganised leisure time physical activity. Conflicting injury incidence rates were reported for physical education. Subgroup analysis suggested that girls and children with low habitual levels of physical activity are at increased injury risk. A limitation of the review is that no standard bias assessment was available for this specific context. Children are at an inherent injury risk while participating in physical activities. Most injury prevention efforts have focussed on the sports setting, but our results suggest that many children sustain an injury

  2. Efficacy of interventions to improve physical activity levels in individuals with stroke: a systematic review protocol

    Science.gov (United States)

    Aguiar, Larissa Tavares; Martins, Júlia Caetano; Nadeau, Sylvie; Britto, Raquel Rodrigues; Teixeira-Salmela, Luci F; Faria, Christina D C M

    2017-01-01

    Introduction Stroke is a leading health problem worldwide and an important cause of disability. Stroke survivors show low levels of physical activity, and increases in physical activity levels may improve function and health status. Therefore, the aims are to identify which interventions that have been employed to increase physical activity levels with stroke survivors, to verify their efficacy and to identify the gaps in the literature. Methods and analysis A systematic review of randomised controlled trials that investigated the efficacy of interventions aiming at increasing physical activity levels of stroke survivors will be conducted. Electronic searches will be performed in the MEDLINE, Physiotherapy Evidence Database (PEDro), Excerpta Medica (EMBASE), Literatura Latino-Americana e do Caribe em Ciências da Saúde (LILACS) and Scientific Electronic Library Online (SCIELO) databases. Hand searches of the reference lists of the included studies or relevant reviews will also be employed. Two independent reviewers will screen all the retrieved titles, abstracts and full texts. A third reviewer will be referred to solve any disagreements. The quality of the included studies will be assessed by the PEDro Rating Scale. This systematic review will also include a qualitative synthesis. Meta-analyses will be performed, if the studies are sufficiently homogeneous. This review will follow the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) statement. The quality of the evidence regarding physical activity will be assessed, according to the Grading of Recommendations Assessment, Development and Evaluation (GRADE). Discussion This systematic review will provide information on which interventions are effective for increasing physical activity levels of stroke survivors. This evidence may be important for clinical decision-making and will allow the identification of gaps in the literature that may be useful for the definition of future research

  3. BOOK REVIEW Handbook of Physics in Medicine and Biology Handbook of Physics in Medicine and Biology

    Science.gov (United States)

    Tabakov, Slavik

    2010-11-01

    This is a multi-author handbook (66 authors) aiming to describe various applications of physics to medicine and biology, from anatomy and physiology to medical equipment. This unusual reference book has 44 chapters organized in seven sections: 1. Anatomical physics; 2. Physics of perception; 3. Biomechanics; 4. Electrical physics; 5. Diagnostic physics; 6. Physics of accessory medicine; 7. Physics of bioengineering. Each chapter has separate page numbering, which is inconvenient but understandable with the number of authors. Similarly there is some variation in the emphasis of chapters: for some the emphasis is more technical and for others clinical. Each chapter has a separate list of references. The handbook includes hundreds of diagrams, images and tables, making it a useful tool for both medical physicists/engineers and other medical/biology specialists. The first section (about 40 pages) includes five chapters on physics of the cell membrane; protein signaling; cell biology and biophysics of the cell membrane; cellular thermodynamics; action potential transmission and volume conduction. The physics of these is well explained and illustrated with clear diagrams and formulae, so it could be a suitable reference for physicists/engineers. The chapters on cellular thermodynamics and action potential transmission have a very good balance of technical/clinical content. The second section (about 85 pages) includes six chapters on medical decision making; senses; somatic senses: touch and pain; hearing; vision; electroreception. Again these are well illustrated and a suitable reference for physicists/engineers. The chapter on hearing stands out with good balance and treatment of material, but some other chapters contain less physics and are close to typical physiological explanations. One could query the inclusion of the chapter on medical decision making, which also needs more detail. The third section (about 80 pages) includes eight chapters on biomechanics

  4. BOOK REVIEW: Seeking Ultimates. An Intuitive Guide to Physics

    Science.gov (United States)

    Brown, Neil

    2000-05-01

    Physics has the reputation of being a difficult and dry subject. Many books have been written in attempts to show that the difficulties are not insurmountable, even for the layman, and to convey some of the fascination it provides for those within it. In Seeking Ultimates Peter Landsberg avoids mathematics, the source of so many difficulties, entirely, and seeks to make physics comprehensible by what he terms intuition. He also emphasizes that there is almost no part of science that is completely understood; there are always areas of incompleteness and uncertainty, capable of providing exciting new results, and examples of this are highlighted throughout the book. After an introduction Landsberg starts with macroscopic phenomena for ease of understanding, though one might question whether the chosen topic of thermodynamics is ever going to be easy. Next he looks at microscopic effects, from atomic structure to the fundamental particles of the standard model and their interactions. There follow chapters on time and entropy, on chaos theory, on quantum mechanics and then cosmology. The final chapters look at physical constants (including the anthropic principle), whether physics has room for a creator God (the conclusion is that this is not the province of science), and some thoughts on science as a human activity. The chosen topics are those which have been important in the late twentieth century and remain important. Each chapter cites an eminent scientist as a `hero', though little is made of this. There are occasional historical notes, set in boxes, and a few short poems to leaven the text. What the book achieves is difficult to assess. Removing mathematics and adding a glossary of technical terms do not necessarily allow non-scientists to enjoy the text, as the publisher's note on the back cover suggests. The concepts can baffle the layman even more than the mathematics, and one of the most difficult of all physical concepts permeates so much of this book

  5. Playing it safe: the influence of neighbourhood safety on children's physical activity. A review.

    Science.gov (United States)

    Carver, Alison; Timperio, Anna; Crawford, David

    2008-06-01

    Compared with previous generations, children spend less time playing outdoors and have lower participation rates in active transport. Many studies have identified lack of neighbourhood safety as a potential barrier to children's physical activity. This review describes concerns regarding 'stranger danger' and road safety, and discusses empirical studies that examine associations between neighbourhood safety and physical activity among youth. Variability of perceptions of safety between parents and youth are examined; 'social traps' are identified; and physical/social environmental interventions aimed at improving neighbourhood safety are discussed. A research agenda is suggested for further study of perceived and objective measures of neighbourhood safety and their associations with children's physical activity.

  6. Health physics aspects of advanced reactor licensing reviews

    Energy Technology Data Exchange (ETDEWEB)

    Hinson, C.S. [Nuclear Regulatory Commission, Washington, DC (United States)

    1995-03-01

    The last Construction Permit to be issued by the U.S. Nuclear Regulatory Commission (NRC) for a U.S. light water reactor (LWR) was granted in the late 1970s. In 1989 the NRC issued 10 CFR Part 52 which is intended to serve as a framework for the licensing of future reactor designs. The NRC is currently reviewing four different future on {open_quotes}next-generation{close_quotes} reactor designs. Two of these designs are classified as evolutionary designs (modified versions of current generation LWRs) and two are advanced designs (reactors incorporating simplified designs and passive means for accident mitigation). These {open_quotes}next-generation{close_quotes} reactor designs incorporate many innovative design features which are intended to maintain personnel doses ALARA and ensure that the annual average collective dose at these reactors does not exceed 100 person-rems (1 person-sievert) per year. This paper discusses some of the ALARA design features which are incorporated in the four {open_quotes}next-generation{close_quotes} reactor designs incorporate many innovative design features which are intended to maintain personnel doses ALARA and ensure that the annual average collective dose at these reactors does not exceed 100 person-rems (1 person-sievert) per year. This paper discusses some of the ALARA design features which are incorporated in the four {open_quotes}next-generation{close_quotes} reactor designs currently being reviewed by the NRC.

  7. [Physical Exercise and Depression in the Elderly : A Systematic Review].

    Science.gov (United States)

    Patiño Villada, Fredy Alonso; Arango Vélez, Elkin Fernando; Baena, Lucidia Zuleta

    2013-06-01

    The literature supports the benefits of exercise in people with depressive disorders, but there is controversy over these benefits in depressed elderly. To determine the effect of different types of exercise on depression in older adults using a systematic review of clinical trials. The Cochrane Library; PubMed-MEDLINE (1966-dic 2010); EMBASE (1980-dic 2010); LILACS (1986-dic 2010); SCIELO (1998-dic 2010); Register of Controlled Trials; manual search in other sources. Clinical trials with people >60 years with diagnosis of depression were included, without restriction by year of publication, language and sex, with exercise intervention structures, controlled with usual care (medication, psychotherapy, electric shock therapy), placebo or non-intervention. Three independent reviewers conducted the search, applied inclusion and exclusion criteria, assessed methodological quality and extracted data; discrepancies were resolved by consensus. The primary outcome was the score for depressive symptoms. A total of 11 studies (n=7195) were identified. In general, exercise produces an improvement in depression in older adults with more evidence in the short-term (3 months) and strength training at high intensity. Exercise is beneficial for older persons with depression, but studies that support this are of low methodological quality and heterogeneous, which makes it necessary to develop clinical trials to clarify the magnitude of the effect and the levels at which it is beneficial. Copyright © 2013 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.

  8. Open-Access Physical Activity Programs for Older Adults: A Pragmatic and Systematic Review.

    Science.gov (United States)

    Balis, Laura E; Strayer, Thomas; Ramalingam, NithyaPriya; Wilson, Meghan; Harden, Samantha M

    2018-01-10

    Open-access, community-based programs are recommended to assist older adults in meeting physical activity guidelines, but the characteristics, impact, and scalability of these programs is less understood. The Land-Grant University Cooperative Extension System, an organization providing education through county-based educators, functions as a delivery system for these programs. A systematic review was conducted to determine characteristics of effective older adult physical activity programs and the extent to which programs delivered in Extension employ these characteristics. A systematic review of peer-reviewed and grey literature was conducted from August 2016 to February 2017. The review was limited to open-access (available to all), community-based physical activity interventions for older adults (≥65 years of age). The peer-reviewed literature search was conducted in PubMed and EBSCOhost; the grey literature search for Extension interventions was conducted through Extension websites, Land-Grant Impacts, and the Journal of Extension. Sixteen peer-reviewed studies and 17 grey literature sources met inclusion criteria and were analyzed. Peer-reviewed and Extension programs were similar in their limited use of behavioral theories and group-based strategies. Compared to Extension programs, those in the peer-reviewed literature were more likely to use a combination of physical activity components and be delivered by trained professionals. The results indicate notable differences between peer-reviewed literature and Extension programs and present an opportunity for Extension programs to more effectively use evidence-based program characteristics, including behavioral theories and group dynamics, a combination of physical activity components, and educator/agent-trained delivery agents. © The Author(s) 2017. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  9. Inverse statistical physics of protein sequences: a key issues review

    Science.gov (United States)

    Cocco, Simona; Feinauer, Christoph; Figliuzzi, Matteo; Monasson, Rémi; Weigt, Martin

    2018-03-01

    In the course of evolution, proteins undergo important changes in their amino acid sequences, while their three-dimensional folded structure and their biological function remain remarkably conserved. Thanks to modern sequencing techniques, sequence data accumulate at unprecedented pace. This provides large sets of so-called homologous, i.e. evolutionarily related protein sequences, to which methods of inverse statistical physics can be applied. Using sequence data as the basis for the inference of Boltzmann distributions from samples of microscopic configurations or observables, it is possible to extract information about evolutionary constraints and thus protein function and structure. Here we give an overview over some biologically important questions, and how statistical-mechanics inspired modeling approaches can help to answer them. Finally, we discuss some open questions, which we expect to be addressed over the next years.

  10. Influence of friends on children's physical activity: a review.

    Science.gov (United States)

    Maturo, Claire C; Cunningham, Solveig A

    2013-07-01

    We examined evidence for friendship influences on children's physical activity (PA) through systematic searches of online databases in May 2012. We identified 106 studies (25 qualitative) published in English since 2000 that analyzed indicators of friendship influences (e.g., communication about PA, friends' PA, and PA with friends) among persons younger than 19 years. Children's PA was positively associated with encouragement from friends (43 of 55 studies indicating a positive relationship), friends' own PA (30/35), and engagement with friends in PA (9/10). These findings are consistent with friends influencing PA, but most studies did not isolate influence from other factors that could explain similarity. Understanding friendship influences in childhood can facilitate the promotion of lifelong healthy habits. PA with friends should be considered in health promotion programs.

  11. Book Review: A Concise History of Solar and Stellar Physics

    Science.gov (United States)

    Phillips, Kenneth J. H.

    2005-01-01

    There is no doubt that the awareness of the often long history and its principal players of a scientific specialty is disappearing among present-day researchers. The reason is the inexorable rise of specialization, in which scientists are expected to keep pace with publications in their own field, not to mention the inevitable round of writing grant proposals and teaching and other mundane responsibilities. The authors of this small book had the intention of rectifying this for solar and stellar physics, disciplines which are still broad enough to embrace fields as diverse as nuclear fusion, magnetohydrodynamics, and the dynamic theory of gas spheres. They take the read on a journey from ancient Greek and middle Eastern astronomy to the late 1990s, one which has an emphasis very much on a theoretical point of view. For the authors, it is the ideas that are central, not the observations.

  12. BOOK REVIEW: Conversations on the Dark Secrets of Physics

    Science.gov (United States)

    Teller, Edward

    2003-07-01

    Over many years Edward Teller delivered a course of Physical Science Appreciation Lectures. This book is based on those lectures, which must have been very stimulating. In the preparation of the book, Edward Teller was assisted by his daughter, Wendy Teller, and also by Wilson Talley. On many pages there are footnotes in the form of conversations between 'ET', who explains, and 'WT', who asks intelligent questions. (It is never clear which 'WT' is which.) I mention these footnotes as they contribute enormously to the charm and humour of the book. The book contains numerous anecdotes, many of which were new to me. The verse in the New Yorker, by Harold Furth, recording the famous meeting between Dr Teller and Dr Anti-Teller, is included. Dr Teller's comment is `The remarkable fact is that Harold got paid for the poem'. Dr Anti-Teller's comment is anti-recorded. The topics in the book include simple mechanics, statistical mechanics, electromagnetism, quantum mechanics and 'uses of new knowledge'. Despite its origins, the book does not avoid mathematics ('I will use mathematics because physics without mathematics is meaningless' (p1)), but Teller does attempt to explain the mathematics he uses. In much of the book the mathematics is at school level, but in his treatment of quantum mechanics he uses differential equations. If one skips past the equations then his final chapters are less mathematically demanding. I have enjoyed reading this book. Teller's approach is refreshing, and his coverage comprehensive and generally authoritative. My only disquiet is over his coverage of electrons in solids, where it would be clearer to consider the one-dimensional case first, before treating the three-dimensional case. There is a substantial discussion on the correspondence principle, wave-particle duality and on the uncertainty principle. His disposal of Schrödinger's notorious cat is masterly. There are questions at the end of each chapter. One question is based on a possible

  13. Systematic review of reviews of intervention components associated with increased effectiveness in dietary and physical activity interventions

    Directory of Open Access Journals (Sweden)

    Evans Philip H

    2011-02-01

    Full Text Available Abstract Background To develop more efficient programmes for promoting dietary and/or physical activity change (in order to prevent type 2 diabetes it is critical to ensure that the intervention components and characteristics most strongly associated with effectiveness are included. The aim of this systematic review of reviews was to identify intervention components that are associated with increased change in diet and/or physical activity in individuals at risk of type 2 diabetes. Methods MEDLINE, EMBASE, CINAHL, PsycInfo, and the Cochrane Library were searched for systematic reviews of interventions targeting diet and/or physical activity in adults at risk of developing type 2 diabetes from 1998 to 2008. Two reviewers independently selected reviews and rated methodological quality. Individual analyses from reviews relating effectiveness to intervention components were extracted, graded for evidence quality and summarised. Results Of 3856 identified articles, 30 met the inclusion criteria and 129 analyses related intervention components to effectiveness. These included causal analyses (based on randomisation of participants to different intervention conditions and associative analyses (e.g. meta-regression. Overall, interventions produced clinically meaningful weight loss (3-5 kg at 12 months; 2-3 kg at 36 months and increased physical activity (30-60 mins/week of moderate activity at 12-18 months. Based on causal analyses, intervention effectiveness was increased by engaging social support, targeting both diet and physical activity, and using well-defined/established behaviour change techniques. Increased effectiveness was also associated with increased contact frequency and using a specific cluster of "self-regulatory" behaviour change techniques (e.g. goal-setting, self-monitoring. No clear relationships were found between effectiveness and intervention setting, delivery mode, study population or delivery provider. Evidence on long

  14. Nonswelling alloy

    International Nuclear Information System (INIS)

    Harkness, S.D.

    1975-01-01

    An aluminum alloy containing one weight percent copper has been found to be resistant to void formation and thus is useful in all nuclear applications which currently use aluminum or other aluminum alloys in reactor positions which are subjected to high neutron doses

  15. Review of Nuclear Physics Experiments for Space Radiation

    Science.gov (United States)

    Norbury, John W.; Miller, Jack; Adamczyk, Anne M.; Heilbronn, Lawrence H.; Townsend, Lawrence W.; Blattnig, Steve R.; Norman, Ryan B.; Guetersloh, Stephen B.; Zeitlin, Cary J.

    2011-01-01

    Human space flight requires protecting astronauts from the harmful effects of space radiation. The availability of measured nuclear cross section data needed for these studies is reviewed in the present paper. The energy range of interest for radiation protection is approximately 100 MeV/n to 10 GeV/n. The majority of data are for projectile fragmentation partial and total cross sections, including both charge changing and isotopic cross sections. The cross section data are organized into categories which include charge changing, elemental, isotopic for total, single and double differential with respect to momentum, energy and angle. Gaps in the data relevant to space radiation protection are discussed and recommendations for future experiments are made.

  16. Physics Physics Annual Review, 1 April 1981-31 March 1982

    International Nuclear Information System (INIS)

    1982-12-01

    In medium-energy pion physics, considerable progress has been made in understanding the propagation and absorption of pions (deltas) in the nuclear medium. An experiment to study neutrino oscillations is being planned at LAMPF with substantial involvement from Argonne. A major effort is being devoted to the scientific and technical considerations involved in proposing to build a multi-GeV C.W. electron accelerator: GEM at Argonne. In heavy-ion physics, the superconducting linac booster is being used with increasing scientific profit. Construction of the ATLAS facility began in FY 1982 and all progress has been on schedule. The importance of the time component of the weak axial-vector current has been studied through the #betta# decay of 16 N. A precision measurement is under way of the 7 Be(p,#betta#) cross section, one of the key components in the solar neutrino anomaly. In nuclear theory, the coupled-channel code for treating heavy-ion inelastic scattering was completed and application to particular experiments began. Nuclear structure theory was applied to interpret decays of high-spin states and inelastic pion scattering. Results of particular interest were obtained in the nuclear force program where the inclusion of 3-body forces led to simultaneous improvement in the binding of 3 He and 4 He and saturation of nuclear matter. The atomic physics research consists of six experimental programs as follows: (1) dissociation and other interactions of energetic molecular ions in solid and gaseous targets; (2) electron spectroscopy with fast atomic and molecular-ion beams; (3) beam-foil research and collision dynamics of heavy ions; (4) photoionization-photoelectron research; (5) high-resolution, laser-rf spectroscopy with atomic and molecular beams; and (6) theoretical atomic physics

  17. Physics Physics Annual Review, 1 April 1981-31 March 1982

    Energy Technology Data Exchange (ETDEWEB)

    1982-12-01

    In medium-energy pion physics, considerable progress has been made in understanding the propagation and absorption of pions (deltas) in the nuclear medium. An experiment to study neutrino oscillations is being planned at LAMPF with substantial involvement from Argonne. A major effort is being devoted to the scientific and technical considerations involved in proposing to build a multi-GeV C.W. electron accelerator: GEM at Argonne. In heavy-ion physics, the superconducting linac booster is being used with increasing scientific profit. Construction of the ATLAS facility began in FY 1982 and all progress has been on schedule. The importance of the time component of the weak axial-vector current has been studied through the ..beta.. decay of /sup 16/N. A precision measurement is under way of the /sup 7/Be(p,..gamma..) cross section, one of the key components in the solar neutrino anomaly. In nuclear theory, the coupled-channel code for treating heavy-ion inelastic scattering was completed and application to particular experiments began. Nuclear structure theory was applied to interpret decays of high-spin states and inelastic pion scattering. Results of particular interest were obtained in the nuclear force program where the inclusion of 3-body forces led to simultaneous improvement in the binding of /sup 3/He and /sup 4/He and saturation of nuclear matter. The atomic physics research consists of six experimental programs as follows: (1) dissociation and other interactions of energetic molecular ions in solid and gaseous targets; (2) electron spectroscopy with fast atomic and molecular-ion beams; (3) beam-foil research and collision dynamics of heavy ions; (4) photoionization-photoelectron research; (5) high-resolution, laser-rf spectroscopy with atomic and molecular beams; and (6) theoretical atomic physics. (WHK)

  18. BOOK REVIEW: The Physical Basis of the Direction of Time

    Science.gov (United States)

    Giulini, Domenico

    2008-10-01

    This is the fifth edition of H Dieter Zeh's classic text on the physical foundations of time-irreversibility in the phenomena. A forerunner of this book was the 1984 German text 'Die Physik der Zeitrichtung' of about 80 pages, which appeared as volume 200 in the Springer series Lecture Notes in Physics. It was soon followed by a largely revised and extended English edition of about twice the length. Since then each new edition has been thoroughly revised and, edition by edition, new topics and chapters have been added. As the author says in the introduction: 'The prime intention of this book is to discuss the relations between various arrows of time, and to search for a universal master arrow'. Correspondingly, after a short chapter on 'the physical concept of time', the author systematically discusses in the remaining five chapters the time arrows in electromagnetic radiation theory, in thermodynamics, in quantum mechanics, in black-hole physics and cosmology, and in quantum cosmology. The chapters on thermodynamics and quantum mechanics slightly outweigh the others in terms of length. The fifth edition now includes two new section on 'cosmic probabilities and history' and 'quantum computers', and the section on the 'expansion of the universe' has been restructured and extended. Other changes concentrate on the sections on radiation damping, decoherence, interpretation of quantum theory, and quantum cosmology. It should also be mentioned that the author maintains a regularly updated website for the book at www.time-direction.de. The reading is always highly stimulating and uses results and ideas from a very broad range of physics, with interspersed historical and philosophical comments. Somehow outstanding and of particular interest is the chapter on quantum cosmology, which raises novel interpretational issues that cannot be found in any other textbook I know of on time asymmetry. As regards the mathematical prerequisites, the reader is assumed to have some

  19. PHYSICS

    CERN Multimedia

    the PAG conveners

    2011-01-01

    The delivered LHC integrated luminosity of more than 1 inverse femtobarn by summer and more than 5 by the end of 2011 has been a gold mine for the physics groups. With 2011 data, we have submitted or published 14 papers, 7 others are in collaboration-wide review, and 75 Physics Analysis Summaries have been approved already. They add to the 73 papers already published based on the 2010 and 2009 datasets. Highlights from each physics analysis group are described below. Heavy ions Many important results have been obtained from the first lead-ion collision run in 2010. The published measurements include the first ever indications of Υ excited state suppression (PRL synopsis), long-range correlation in PbPb, and track multiplicity over a wide η range. Preliminary results include the first ever measurement of isolated photons (showing no modification), J/ψ suppression including the separation of the non-prompt component, further study of jet fragmentation, nuclear modification factor...

  20. BOOK REVIEW: Mastering Physics (4th edn) Macmillan Master Series

    Science.gov (United States)

    Sugden, Chris

    2000-01-01

    The preface to the first edition of this book, in 1982, stated the aim as `presenting ideas with a directness and simplicity that will enable students to achieve maximum comprehension in the shortest possible time'. The fourth edition remains true to this aim, whilst paying some attention to the possibility of using the book alongside classroom work as well as a revision aid. However, it is as a clear concise summary of GCSE level physics (and a little bit beyond) that this book excels. I would recommend it to students as a revision aid at the end of the course and as a reference book during it. There should certainly be a few copies in the school library. Since I see the book's main role as being for the individual use of students it seemed sensible to ask one for his impression of the book having completed GCSE Physics a few months ago, and this is appended below. Philip Britton The book is split into many small, precise subsections and so allows easy reference to the topic you want to know about. The major equations are all included and explained well. The text is quite detailed and includes helpful examples. Concepts are explained in simple stages and in a way that is easy to understand; for example, the phases of the moon and ray diagrams. Resistors, which had been a little difficult for me, are very well explained. A simple detail like putting the names of the circuit symbols beside them on diagrams helps a lot. Throughout the book there are plenty of diagrams used to assist understanding rather than just illustrate the book. Overall I think that it would be best used as a revision aid. It reads very much like a syllabus with added explanation and examples. Perhaps it would be possible for a class to read a section before a lesson so less basic explanation is required during the lesson and other work can be done. The sections are brief enough to allow even the apathetic to complete such a homework assignment.

  1. BOOK REVIEW: Fundamentals of Plasma Physics and Controlled Fusion

    Science.gov (United States)

    Brambilla, Marco

    1998-04-01

    Professor Kenro Miyamoto, already well known for his textbook Plasma Physics for Nuclear Fusion (MIT Press, Cambridge, MA, 1976; revised edition 1989), has now published a new book entitled Fundamentals of Plasma Physics and Controlled Fusion (Iwanami Book Service Center, Tokyo, 1997). To a large extent, the new book is a somewhat shortened and well reorganized version of its predecessor. The style, concise and matter of fact, clearly shows the origin of the text in lectures given by the author to graduate students. As announced by the title, the book is divided into two parts: the first part (about 250 pages) is a general introduction to the physics of plasmas, while the second, somewhat shorter, part (about 150 pages), is devoted to a description of the most important experimental approaches to achieving controlled thermonuclear fusion. Even in the first part, moreover, the choice of subjects is consistently oriented towards the needs of fusion research. Thus, the introduction to the behaviour of charged particles (particle motion, collisions, etc.) and to the collective description of plasmas is quite short, although the reader will get a flavour of all the most important topics and will find a number of examples chosen for their relevance to fusion applications (only the presentation of the Vlasov equation, in the second section of Chapter 4, might be criticized as so concise as to be almost misleading, since the difference between microscopic and macroscopic fields is not even mentioned). Considerably more space is devoted to the magnetohydrodynamic (MHD) description of equilibrium and stability. This part includes the solution of the Grad-Shafranov equation for circular tokamaks, a brief discussion of Pfirsch-Schlüter, neoclassical and anomalous diffusion, and two relatively long chapters on the most important ideal and resistive MHD instabilities of toroidal plasmas; drift and ion temperature gradient driven instabilities are also briefly presented. The

  2. Databases in High Energy Physics a critial review

    CERN Document Server

    Shiers, J D

    2007-01-01

    The year 2000 is marked by a plethora of significant milestones in the history of High Energy Physics. Not only the true numerical end to the second millennium, this watershed year saw the final run of CERN's Large Electron-Positron collider (LEP) - the world-class machine that had been the focus of the lives of many of us for such a long time. It is also closely related to the subject of this chapter in the following respects: - Classified as a nuclear installation, information on the LEP machine must be retained indefinitely. This represents a challenge to the database community that is almost beyond discussion - archiving of data for a relatively small number of years is indeed feasible, but retaining it for centuries, millennia or more is a very different issue; - There are strong scientific arguments as to why the data from the LEP machine should be retained for a short period. However, the complexity of the data itself, the associated metadata and the programs that manipulate it make even this a huge ch...

  3. A review of physical and cognitive interventions in aging.

    Science.gov (United States)

    Bamidis, P D; Vivas, A B; Styliadis, C; Frantzidis, C; Klados, M; Schlee, W; Siountas, A; Papageorgiou, S G

    2014-07-01

    Maintaining a healthy brain is a critical factor for the quality of life of elderly individuals and the preservation of their independence. Challenging aging brains through cognitive training and physical exercises has shown to be effective against age-related cognitive decline and disease. But how effective are such training interventions? What is the optimal combination/strategy? Is there enough evidence from neuropsychological observations, animal studies, as well as, structural and functional neuroimaging investigations to interpret the underlying neurobiological mechanisms responsible for the observed neuroplasticity of the aging brain? This piece of work summarizes recent findings toward these questions, but also highlights the role of functional brain connectivity work, an emerging discipline for future research in healthy aging and the study of the underlying mechanisms across the life span. The ultimate aim is to conclude on recommended multimodal training, in light of contemporary trends in the design of exergaming interventions. The latter issue is discussed in conjunction with building up neuroscientific knowledge and envisaged future research challenges in mapping, understanding and training the aging brain. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Systematic Review of the Effectiveness of Physical Therapy Modalities in Women With Provoked Vestibulodynia.

    Science.gov (United States)

    Morin, Mélanie; Carroll, Marie-Soleil; Bergeron, Sophie

    2017-07-01

    Pelvic floor muscle physical therapy is recommended in clinical guidelines for women with provoked vestibulodynia (PVD). Including isolated or combined treatment modalities, physical therapy is viewed as an effective first-line intervention, yet no systematic review concerning the effectiveness of physical therapy has been conducted. To systematically appraise the current literature on the effectiveness of physical therapy modalities for decreasing pain during intercourse and improving sexual function in women with PVD. A systematic literature search using PubMed, Scopus, CINHAL, and PEDro was conducted until October 2016. Moreover, a manual search from reference lists of included articles was performed. Ongoing trials also were reviewed using clinicaltrial.gov and ISRCTNregistry. Randomized controlled trials, prospective and retrospective cohorts, and case reports evaluating the effect of isolated or combined physical therapy modalities in women with PVD were included in the review. Main outcome measures were pain during intercourse, sexual function, and patient's perceived improvement. The literature search resulted in 43 eligible studies including 7 randomized controlled trials, 20 prospective studies, 5 retrospective studies, 6 case reports, and 6 study protocols. Most studies had a high risk of bias mainly associated with the lack of a comparison group. Another common bias was related to insufficient sample size, non-validated outcomes, non-standardized intervention, and use of other ongoing treatment. The vast majority of studies showed that physical therapy modalities such as biofeedback, dilators, electrical stimulation, education, multimodal physical therapy, and multidisciplinary approaches were effective for decreasing pain during intercourse and improving sexual function. The positive findings for the effectiveness of physical therapy modalities in women with PVD should be investigated further in robust and well-designed randomized controlled trials

  5. Effectiveness of interventions to promote physical activity in children and adolescents: systematic review of controlled trials.

    Science.gov (United States)

    van Sluijs, Esther M F; McMinn, Alison M; Griffin, Simon J

    2007-10-06

    To review the published literature on the effectiveness of interventions to promote physical activity in children and adolescents. Systematic review. Literature search using PubMed, SCOPUS, Psychlit, Ovid Medline, Sportdiscus, and Embase up to December 2006. Review methods Two independent reviewers assessed studies against the following inclusion criteria: controlled trial, comparison of intervention to promote physical activity with no intervention control condition, participants younger than 18 years, and reported statistical analyses of a physical activity outcome measure. Levels of evidence, accounting for methodological quality, were assessed for three types of intervention, five settings, and three target populations. The literature search identified 57 studies: 33 aimed at children and 24 at adolescents. Twenty four studies were of high methodological quality, including 13 studies in children. Interventions that were found to be effective achieved increases ranging from an additional 2.6 minutes of physical education related physical activity to 283 minutes per week of overall physical activity. Among children, limited evidence for an effect was found for interventions targeting children from low socioeconomic populations, and environmental interventions. Strong evidence was found that school based interventions with involvement of the family or community and multicomponent interventions can increase physical activity in adolescents. Some evidence was found for potentially effective strategies to increase children's levels of physical activity. For adolescents, multicomponent interventions and interventions that included both school and family or community involvement have the potential to make important differences to levels of physical activity and should be promoted. A lack of high quality evaluations hampers conclusions concerning effectiveness, especially among children.

  6. Workplace accommodations for persons with physical disabilities: evidence synthesis of the peer-reviewed literature.

    Science.gov (United States)

    Padkapayeva, Kathy; Posen, Andrew; Yazdani, Amin; Buettgen, Alexis; Mahood, Quenby; Tompa, Emile

    2017-10-01

    To identify and synthesize research evidence on workplace accommodations used by employers to recruit, hire, retain, and promote persons with physical disabilities. A structured search of six electronic journal databases was undertaken to identify peer-reviewed literature on the topic published from January 1990 to March 2016. Articles describing or evaluating workplace disability accommodation policies and practices were given a full-text review. Topic experts were contacted to identify additional studies. Details on specific accommodations described in 117 articles were synthesized and organized into three groups comprised of a total of 12 categories. The majority of studies did not rigorously evaluate effectiveness or cost-effectiveness of the accommodations under study. This evidence synthesis provides an overview of the peer-reviewed literature of value to occupational rehabilitation professionals and employers seeking guidance on workplace accommodation policies and practices for persons with physical disabilities. A wide range of accommodation options is available for addressing physical, social, and attitudinal barriers to successful employment. Besides physical/technological modifications, accommodations to enhance workplace flexibility and worker autonomy and strategies to promote workplace inclusion and integration are important. More comprehensive reporting and evaluations of the effectiveness of accommodations in research literature are needed to develop best practices for accommodating persons with disabilities. Implications for rehabilitation There is a substantial peer-reviewed literature that provides insights into the barriers for persons with physical disabilities and the workplace accommodation practices to address them, though rigorous evaluations of effectiveness and cost-effectiveness are uncommon. Attitudinal and social barriers stemming from stereotypes, ignorance and lack of knowledge are as important as physical barriers to employment for

  7. Surface Texture-Based Surface Treatments on Ti6Al4V Titanium Alloys for Tribological and Biological Applications: A Mini Review

    Directory of Open Access Journals (Sweden)

    Naiming Lin

    2018-03-01

    Full Text Available Surface texture (ST has been confirmed as an effective and economical surface treatment technique that can be applied to a great range of materials and presents growing interests in various engineering fields. Ti6Al4V which is the most frequently and successfully used titanium alloy has long been restricted in tribological-related operations due to the shortcomings of low surface hardness, high friction coefficient, and poor abrasive wear resistance. Ti6Al4V has benefited from surface texture-based surface treatments over the last decade. This review begins with a brief introduction, analysis approaches, and processing methods of surface texture. The specific applications of the surface texture-based surface treatments for improving surface performance of Ti6Al4V are thoroughly reviewed from the point of view of tribology and biology.

  8. Surface Texture-Based Surface Treatments on Ti6Al4V Titanium Alloys for Tribological and Biological Applications: A Mini Review.

    Science.gov (United States)

    Lin, Naiming; Li, Dali; Zou, Jiaojuan; Xie, Ruizhen; Wang, Zhihua; Tang, Bin

    2018-03-24

    Surface texture (ST) has been confirmed as an effective and economical surface treatment technique that can be applied to a great range of materials and presents growing interests in various engineering fields. Ti6Al4V which is the most frequently and successfully used titanium alloy has long been restricted in tribological-related operations due to the shortcomings of low surface hardness, high friction coefficient, and poor abrasive wear resistance. Ti6Al4V has benefited from surface texture-based surface treatments over the last decade. This review begins with a brief introduction, analysis approaches, and processing methods of surface texture. The specific applications of the surface texture-based surface treatments for improving surface performance of Ti6Al4V are thoroughly reviewed from the point of view of tribology and biology.

  9. What are the health benefits of physical activity in type 1 diabetes mellitus? A literature review.

    Science.gov (United States)

    Chimen, M; Kennedy, A; Nirantharakumar, K; Pang, T T; Andrews, R; Narendran, P

    2012-03-01

    Physical activity improves well-being and reduces the risk of heart disease, cancer and type 2 diabetes mellitus in the general population. In individuals with established type 2 diabetes, physical activity improves glucose and lipid levels, reduces weight and improves insulin resistance. In type 1 diabetes mellitus, however, the benefits of physical activity are less clear. There is poor evidence for a beneficial effect of physical activity on glycaemic control and microvascular complications, and significant risk of harm through hypoglycaemia. Here we review the literature relating to physical activity and health in type 1 diabetes. We examine its effect on a number of outcomes, including glycaemic control, lipids, blood pressure, diabetic complications, well-being and overall mortality. We conclude that whilst there is sufficient evidence to recommend physical activity in the management of type 1 diabetes, it is still unclear as to what form, duration and intensity should be recommended and whether there is benefit for many of the outcomes examined.

  10. Increasing physical activity for the treatment of hypertension: a systematic review and meta-analysis.

    Science.gov (United States)

    Semlitsch, Thomas; Jeitler, Klaus; Hemkens, Lars G; Horvath, Karl; Nagele, Eva; Schuermann, Christoph; Pignitter, Nicole; Herrmann, Kirsten H; Waffenschmidt, Siw; Siebenhofer, Andrea

    2013-10-01

    Low physical activity has been identified as a major risk factor for cardiovascular disease. Medical societies therefore recommend increased physical activity be part of any antihypertensive therapy. Focusing on patient-relevant outcomes such as mortality and cardiovascular events, this review was conducted to assess the long-term effects of interventions aiming at increasing physical activity in comparison with no such interventions on adult patients with essential hypertension. We searched for high-quality systematic reviews in MEDLINE, EMBASE, Cochrane Database of Systematic Reviews (Cochrane Reviews), Database of Abstracts of Reviews of Effects (Other Reviews) and Health Technology Assessment Database (Technology Assessments) published between 1997 and February 2009 and for randomized controlled trials (RCTs) in MEDLINE, EMBASE and Cochrane Central Register of Controlled Trials (Clinical Trials) published before September 2012. Additional studies were identified by hand searching reference lists of reviews. RCTs with at least 24 weeks' follow-up that evaluated the effect of increased physical activity on the blood pressure of adults with essential hypertension were included in our review. Primary outcomes were all-cause mortality, cardiovascular morbidity and mortality, end-stage renal disease, quality of life and adverse events. When appropriate, we used random effects meta-analyses to determine mean difference with 95 % confidence intervals for each endpoint. All data were analysed using the Review Manager software version 5.0.24 from the Cochrane Collaboration. None of the included nine trials, covering 891 patients with hypertension, provided sufficient data on patient-relevant outcomes such as mortality, cardiovascular events or injuries related to physical activity. Information on changes in systolic and diastolic blood pressure was provided for all included trials. The majority of the included RCTs reported that increased physical activity led to a

  11. BOOK REVIEW: New Understanding Physics for Advanced Level

    Science.gov (United States)

    Breithaupt, Jim

    2000-09-01

    Breithaupt's new book is big: at 727 pages, it will be a hefty addition to any student's bag. According to the preface, the book is designed to help students achieve the transition from GCSE to A-level and to succeed well at this level. It also aims to cover the requirements of the compulsory parts of all new syllabuses and to cover most of the optional material, too. The book is organized into seven themes along traditional lines: mechanics, materials, fields, waves, electricity, inside the atom, and physics in medicine. Each theme begins with a colourful title page that outlines what the theme is about, lists the applications that students will meet in their reading, identifies prior learning from GCSE and gives a checklist of what students should be able to do once they have finished their reading of the theme. This is all very useful. The text of the book is illustrated with many colourful photographs, pictures and cartoons, but despite this it looks very dense. There are a lot of words on every page in a small font that makes them seem very unfriendly, and although the book claims to be readable I rather doubt that the layout will encourage voluntary reading of the text. Each chapter ends with a useful summary and a selection of short questions that allow students to test their understanding. Each theme has a set of multiple choice and long questions. Some of the questions have an icon referring the student to the accompanying CD (more of this later). There is much up-to-date material in the book. For example, the section on cosmology gives a brief description of the inflationary scenario within the Big Bang model of the origin of the universe, although no mechanism for the inflation is given, which might prove unsatisfying to some students. I do have some reservations about the presentation of some topics within the book: the discussion of relativistic mass, for example, states that `Einstein showed that the mass ... is given by the formula ...' and quotes

  12. A systematic review of workplace health promotion interventions for increasing physical activity.

    Science.gov (United States)

    Malik, Sumaira H; Blake, Holly; Suggs, L Suzanne

    2014-02-01

    The benefits of an active lifestyle are widely documented, yet studies show that only a small proportion of adults engage in sufficient levels of physical activity. The workplace presents an ideal avenue for delivering initiatives to promote physical activity, overcoming commonly cited barriers such as a 'lack of time' and providing access to a large intersection of society. The purpose of this study was to (1) explore the types of interventions workplaces implement to promote physical activity among staff, (2) describe the characteristics of those interventions, (3) understand whether these interventions positively impact on activity levels, and (4) assess the methodological quality of studies. A systematic review of workplace physical activity interventions published up to April 2011 was conducted to identify types of interventions and their outcomes. Of the 58 studies included, the majority utilized health promotion initiatives. There were six physical activity/exercise interventions, 13 counselling/support interventions, and 39 health promotion messages/information interventions. Thirty-two of these studies showed a statistically significant increase in a measure of physical activity against a control group at follow-up. While the studies included in this review show some evidence that workplace physical activity interventions can be efficacious, overall the results are inconclusive. Despite the proliferation of research in this area, there is still a need for more well-designed studies to fully determine the effectiveness of workplace interventions for increasing physical activity and to identify the types of interventions that show the most promise. © 2013 The British Psychological Society.

  13. Relationship between eating behaviors and physical activity of preschoolers and their peers: a systematic review.

    Science.gov (United States)

    Ward, Stéphanie A; Bélanger, Mathieu F; Donovan, Denise; Carrier, Natalie

    2016-04-14

    Children learn by observing and imitating others, meaning that their eating behaviors and physical activity may be influenced by their peers. This paper systematically reviews how preschoolers' eating behaviors and physical activity relate to their peers' behaviors, and discusses avenues for future research. Six databases were searched for quantitative, peer-reviewed studies published up to July 2015 reporting on the correlates, predictors or effectiveness of peers on eating behaviors and physical activity in preschoolers. Risk of bias was independently assessed by two evaluators using the Quality Assessment Tool for Quantitative Studies. Thirteen articles were included: six measured physical activity, and seven assessed eating behaviors. Four of the six physical activity studies reported that children were more active when peers were present, while large peer group size was negatively associated with physical activity in two cross-sectional studies. All nutrition interventions reported that children's eating behaviors may be influenced by their peers. Although supported by weak evidence, peers appear to influence children's eating behaviors and physical activity. However, this influence may be moderated by the number of peers, gender, age and the perceived status of the role models. Future obesity prevention interventions should consider involving peers as agents for positive eating behaviors and physical activity in preschoolers.

  14. The Effects of Physical Activity on Serum Visfatin Level: A Literature Review

    Directory of Open Access Journals (Sweden)

    Mohsen Ghanbarzadeh

    2017-06-01

    Full Text Available Higher concentration of plasma visfatin in obese and diabetic subjects compared with their healthy counterparts shows visfatin relationship to obesity and overweight. This article reviewed the studies on contradictory and different notions regarding the role of physical activity in visfatin response following aerobic and resistance exercises. Recent reports on the impact of physical activity and exercise on visfatin concentration is contradictory. Some studies have identified that exercise can reduce visfatin concentration depending on the duration of physical activity and calorie expenditure, while others have not reported any changes in visfatin concentration. The present review indicated that a balanced diet, low in fat, and physical exercise (aerobic and aerobic-resistance exercises can reduce blood visfatin levels depending on the severity and duration, while resistance training alone exerts no significant effects on serum visfatin level.

  15. Recent research and developments on wrought magnesium alloys

    Directory of Open Access Journals (Sweden)

    Sihang You

    2017-09-01

    Full Text Available Wrought magnesium alloys attract special interests as lightweight structural material due to their homogeneous microstructure and enhanced mechanical properties compared to as-cast alloys. In this contribution, recent research and developments on wrought magnesium alloys are reviewed from the viewpoint of the alloy design, focusing on Mg-Al, Mg-Zn and Mg-rare earth (RE systems. The effects of different alloying elements on the microstructure and mechanical properties are described considering their strengthening mechanisms, e.g. grain refinement, precipitation and texture hardening effect. Finally, the new alloy design and also the future research of wrought magnesium alloys to improve their mechanical properties are discussed.

  16. Review of corrosion phenomena on zirconium alloys, niobium, titanium, inconel, stainless steel, and nickel plate under irradiation

    International Nuclear Information System (INIS)

    Johnson, A.B. Jr.

    1975-01-01

    The role of nuclear fluxes in corrosion processes was investigated in ATR, ETR, PRTR, and in Hanford production reactors. Major effort was directed to zirconium alloy corrosion parameter studies. Corrosion and hydriding results are reported as a function of oxygen concentration in the coolant, flux level, alloy composition, surface pretreatment, and metallurgical condition. Localized corrosion and hydriding at sites of bonding to dissimilar metals are described. Corrosion behavior on specimens transferred from oxygenated to low-oxygen coolants in ETR and ATR experiments is compared. Mechanism studies suggest that a depression in the corrosion of the Zr--2.5Nb alloy under irradiation is due to radiation-induced aging. The radiation-induced onset of transition on several alloys is in general a gradual process which nucleates locally, causing areas of oxide prosity which eventually encompass the surface. Examination of Zry-2 process tubes reveals that accelerated corrosion has occurred in low-oxygen coolants. Hydrogen contents are relatively low, but show some localized profiles. Gross hydriding has occurred on process tubes containing aluminum spacers, apparently by a galvanic charging mechanism. Titanium paralleled Zry-2 in corrosion behavior under irradiation. Niobium corrosion was variable, but did not appear to be strongly influenced by radiation. Corrosion rates on Inconel and stainless steel were only slightly higher in-flux than out-of-reactor. Corrosion rates on nickel-plated aluminum appeared to vary substantially with preexposure treatments, but the rates generally were accelerated compared to rates on unirradiated coupons. (59 references, 11 tables, 12 figs.)

  17. A Review of Procedures for Summing Kapteyn Series in Mathematical Physics

    OpenAIRE

    Tautz, R. C.; Lerche, I.

    2009-01-01

    Since the discussion of Kapteyn series occurrences in astronomical problems the wealth of mathematical physics problems in which such series play dominant roles has burgeoned massively. One of the major concerns is the ability to sum such series in closed form so that one can better understand the structural and functional behavior of the basic physics problems. The purpose of this review article is to present some of the recent methods for providing such series in closed form with appl...

  18. Physical activity interventions in the workplace: a review and future for New Zealand research

    OpenAIRE

    Badland, H. M.; Schofield, G. M.

    2004-01-01

    Aim: To examine the worksite physical activity intervention literature and discuss whether the findings are applicable to New Zealand worksite environments. Data sources: Information was sourced from major health databases using key words physical activity, intervention, worksite, workplace, and health promotion. The remainder of the literature search was directed from citations in the articles sourced from the original search. Study selection: Studies included in the review were related to w...

  19. Physics Division annual review, 1 April 1986-31 March 1987

    International Nuclear Information System (INIS)

    1987-08-01

    This review presents a broad view of the research activities within the Division for the year ending in March 1987. Major topic areas are: Medium Energy Physics Research; Theoretical Nuclear Physics; Superconducting Linac Development, and Accelerator Operations. Research at ATLAS is also included as a broad topic. Included in this research are studies in the areas of: Quasielastic Processes and Strongly Damped Collisions; Fusion and Fission of Heavy Ions; High Angular Momentum States in Nuclei; Accelerator Mass Spectroscopy; and Equipment Development

  20. A review of state regulations to promote infant physical activity in child care

    OpenAIRE

    Slining, Meghan M; Benjamin Neelon, Sara E; Duffey, Kiyah J

    2014-01-01

    Background The purpose of this study was to review state regulations promoting increased physical activity and decreased sedentary behaviors in infants in child care and to assess consistency with recent Institute of Medicine (IOM) recommendations. Methods We compared existing state and territory licensing and administrative regulations to recent IOM recommendations to promote physical activity and decrease sedentary time in very young children attending out-of-home child care (both ...

  1. EFFECT OF PHYSICAL ACTIVITY ON CARDIOMETABOLIC MARKERS IN ADOLESCENTS: SYSTEMATIC REVIEW

    OpenAIRE

    Miranda, Valter Paulo Neves; Amorim, Paulo Roberto dos Santos; Oliveira, Nathália Cristina Borges; Peluzio, Maria do Carmo Gouveia; Priore, Silvia Eloiza

    2016-01-01

    ABSTRACT The accumulation of body fat is a major risk factor for cardiometabolic diseases. Obesity can be considered a chronic systemic inflammatory disease in adults and younger people. The control of subclinical inflammation process through the practice of physical activity (PA) can mitigate the effects of risk factors that trigger atherosclerosis that worsens with advancing age. The objective of this study was to conduct a systematic review of the influence of physical activity and/or exer...

  2. Physical therapy interventions for degenerative lumbar spinal stenosis: a systematic review.

    Science.gov (United States)

    Macedo, Luciana Gazzi; Hum, Abraham; Kuleba, Laura; Mo, Joey; Truong, Linda; Yeung, Mankeen; Battié, Michele C

    2013-12-01

    Physical therapy is commonly prescribed for patients with lumbar spinal stenosis (LSS); however, little is known about its effectiveness. The purpose of this study was to systematically review randomized controlled trials (RCTs), controlled trials, and cohort studies evaluating the effectiveness of physical therapy for LSS. Studies were searched on electronic databases to January 2012. Inclusion criteria were: clinical diagnosis of LSS with confirmatory imaging, evaluation of physical therapy treatment, presence of a comparison group, and outcomes of pain, disability, function, or quality of life. Outcomes were extracted and, when possible, pooled using RevMan 5, a freely available review program from the Cochrane Library. Ten studies were included: 5 RCTs, 2 controlled trials, 2 mixed-design studies, and 1 longitudinal cohort study. Pooled effects of 2 studies revealed that the addition of a physical therapy modality to exercise had no statistically significant effect on outcome. Pooled effects results of RCTs evaluating surgery versus physical therapy demonstrated that surgery was better than physical therapy for pain and disability at long term (2 years) only. Other results suggested that exercise is significantly better than no exercise, that cycling and body-weight-supported treadmill walking have similar effects, and that corsets are better than no corsets. The limitations of this review include the low quality and small number of studies, as well as the heterogeneity in outcomes and treatments. No conclusions could be drawn from the review regarding which physical therapy treatment is superior for LSS. There was low-quality evidence suggesting that modalities have no additional effect to exercise and that surgery leads to better long-term (2 years) outcomes for pain and disability, but not walking distance, than physical therapy in patients with LSS.

  3. Impact of Physical Activity Intervention Programs on Self-Efficacy in Youths: A Systematic Review

    Science.gov (United States)

    Cataldo, Rosa; John, Janice; Chandran, Latha; Pati, Susmita; Shroyer, A. Laurie W.

    2013-01-01

    Lack of physical activity has contributed to the nation's childhood obesity crisis, but the impact of physical activity on self-efficacy as a mediator of behavior change has not been examined. This systematic review (SR) describes the published evidence related to the impact of physical activity intervention programs on self-efficacy among youths. From January 2000 to June 2011, the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) standards were used to identify publications from PubMed, PsychInfo, Web of Knowledge, and the Cochran Database of Systematic Reviews. The Cochrane Population, Intervention, Control, Outcome, Study Design (PICOS) approach guided this SR articles selection and evaluation process. Of the 102 publications screened, 10 original studies matched the SR inclusion criteria. The types of physical activity interventions and self-efficacy assessments for these 10 studies were diverse. Of the 10 included articles, 6 articles identified an improvement in post-self-efficacy assessments compared to baseline and 4 showed no effect. In conclusion, physical activity intervention programs may improve self-efficacy in youths. A standardized approach to classify and measure self-efficacy is required. Further research is needed to quantify the association of self-efficacy ratings after completing physical activity interventions with objective health improvements, such as weight loss. PMID:24555151

  4. Physical Activity Interventions in Faith-Based Organizations: A Systematic Review.

    Science.gov (United States)

    Tristão Parra, Maíra; Porfírio, Gustavo J M; Arredondo, Elva M; Atallah, Álvaro N

    2018-03-01

    To review and assess the effectiveness of physical activity interventions delivered in faith-based organizations. We searched the Cochrane Library, DoPHER, EMBASE, LILACS, MEDLINE, PsycINFO, WHO ICTRP, and Clinicaltrials.gov databases until January 2016, without restriction of language or publication date. Randomized and nonrandomized controlled trials investigating physical activity interventions for adults delivered in faith-based organizations. Two independent reviewers extracted data and assessed study methodological quality. We used relative risk and mean difference with 95% confidence interval to estimate the effect of the interventions on measures of physical activity, physical fitness, and health. The review included 18 studies. Study participants were predominantly female, and the majority of trials were conducted in the United States. Study heterogeneity did not allow us to conduct meta-analyses. Although interventions delivered in faith-based organizations increased physical activity and positively influenced measures of health and fitness in participants, the quality of the evidence was very low. Faith-based organizations are promising settings to promote physical activity, consequently addressing health disparities. However, high-quality randomized clinical trials are needed to adequately assess the effectiveness of interventions delivered in faith-based organizations.

  5. Mapping review of accessible pedestrian infrastructures for individuals with physical disabilities.

    Science.gov (United States)

    Gamache, Stéphanie; Routhier, François; Morales, Ernesto; Vandersmissen, Marie-Hélène; Boucher, Normand

    2018-03-14

    Due to the ageing population and higher prevalence of individuals living with physical disabilities, there is a critical need for inclusive practices when designing accessible pedestrian infrastructures for ensuring social participation and equal opportunities. Summarize the physical characteristics of current pedestrian infrastructure design for individuals with physical disabilities (IPD - motor, visual and hearing) found in the scientific literature and assess its quality. A mapping review of the existing literature on pedestrian infrastructures specifically built for individuals with physical disabilities identifying measurable physical characteristics for their design was done using online databases (Urban Studies Abstracts, Geobase, PubMed, and Cairn and secondary research). Information about accessibility (physical characteristics) of existing pedestrian infrastructures was extracted. The quality of the evidence was assessed using the Guidelines for critical review form - Quantitative studies and Qualitative studies version 2.0 (SAGE Publications, Inc., Thousand Oaks, CA). Of the 1131 articles identified, forty-one articles examined access to bus stops, curb ramps, lighting, pedestrian crossings, ramps, shared spaces, sidewalks and steps. Six articles reported on more than one physical disability. Quality scores were generally low (quantitative: 2-11/15 and qualitative: 1-22/23). Recommended design features differed for the same infrastructure. While there were a fair number of articles (n = 41) documenting accessible design features of pedestrian infrastructures, the quality of the evidence was low. The review identified knowledge gaps. Although specific design solutions exist, they have not yet been tested among individuals with various or multiple types of physical disabilities to ensure access to pedestrian infrastructures by all. Implications for Rehabilitation Pedestrian infrastructures still pose problems to mobility, limiting social participation

  6. Systematic review of behaviour change techniques to promote participation in physical activity among people with dementia.

    Science.gov (United States)

    Nyman, Samuel R; Adamczewska, Natalia; Howlett, Neil

    2018-02-01

    The objective of this study was to systematically review the evidence for the potential promise of behaviour change techniques (BCTs) to increase physical activity among people with dementia (PWD). PsychINFO, MEDLINE, CINAHL, and the Cochrane Central Register of Controlled Trials databases were searched 01/01/2000-01/12/2016. Randomized controlled/quasi-randomized trials were included if they recruited people diagnosed/suspected to have dementia, used at least one BCT in the intervention arm, and had at least one follow-up measure of physical activity/adherence. Studies were appraised using the Cochrane Collaboration Risk of Bias Tool, and BCTs were coded using Michie et al., 2013, Annals of Behavioral Medicine, 46, 81. taxonomy. Intervention findings were narratively synthesized as either 'very promising', 'quite promising', or 'non-promising', and BCTs were judged as having potential promise if they featured in at least twice as many very/quite promising than non-promising interventions (as per Gardner et al., 2016, Health Psychology Review, 10, 89). Nineteen articles from nine trials reported physical activity findings on behavioural outcomes (two very promising, one quite promising, and two non-promising) or intervention adherence (one quite promising and four non-promising). Thirteen BCTs were used across the interventions. While no BCT had potential promise to increase intervention adherence, three BCTs had potential promise for improving physical activity behaviour outcomes: goal setting (behaviour), social support (unspecified), and using a credible source. Three BCTs have potential promise for use in future interventions to increase physical activity among PWD. Statement of contribution What is already known on this subject? While physical activity is a key lifestyle factor to enhance and maintain health and wellbeing amongst the general population, adults rarely participate in sufficient levels to obtain these benefits. Systematic reviews suggest that

  7. Behaviour change interventions to promote physical activity in rheumatoid arthritis: a systematic review.

    Science.gov (United States)

    Larkin, Louise; Gallagher, Stephen; Cramp, Fiona; Brand, Charles; Fraser, Alexander; Kennedy, Norelee

    2015-10-01

    Research has shown that people who have rheumatoid arthritis (RA) do not usually participate in enough physical activity to obtain the benefits of optimal physical activity levels, including quality of life, aerobic fitness and disease-related characteristics. Behaviour change theory underpins the promotion of physical activity. The aim of this systematic review was to explore behaviour change interventions which targeted physical activity behaviour in people who have RA, focusing on the theory underpinning the interventions and the behaviour change techniques utilised using specific behaviour change taxonomy. An electronic database search was conducted via EBSCOhost, PubMed, Cochrane Central Register of Controlled Trials and Web of Science databases in August 2014, using Medical Subject Headings and keywords. A manual search of reference lists was also conducted. Randomised control trials which used behaviour change techniques and targeted physical activity behaviour in adults who have RA were included. Two reviewers independently screened studies for inclusion. Methodological quality was assessed using the Cochrane risk of bias tool. Five studies with 784 participants were included in the review. Methodological quality of the studies was mixed. The studies consisted of behaviour change interventions or combined practical physical activity and behaviour change interventions and utilised a large variety of behaviour change techniques. Four studies reported increased physical activity behaviour. All studies used subjective methods of assessing physical activity with only one study utilising an objective measure. There has been varied success of behaviour change interventions in promoting physical activity behaviour in people who have RA. Further studies are required to develop and implement the optimal behaviour change intervention in this population.

  8. Interventions to promote physical activity in older people with type 2 diabetes mellitus: A systematic review

    Directory of Open Access Journals (Sweden)

    Sazlina eShariff-Ghazali

    2013-12-01

    Full Text Available Introduction: Type 2 diabetes mellitus (T2DM among people aged 60 years and above is a growing public health problem. Regular physical activity is one of the key elements in the management of T2DM. Recommendations suggest that older people with T2DM will benefit from regular physical activity for better disease control and delaying complications. Despite the known benefits, many remain sedentary. Hence, this review assessed interventions for promoting physical activity in persons aged 65 years and older with type 2 diabetes mellitus. Methods: A literature search was conducted using OvidMEDLINE, PubMed, EMBASE, SPORTDiscus and CINAHL databases to retrieve articles published between January 2000 and December 2012. Randomised controlled trials and quasi-experimental designs comparing different strategies to increase physical activity level in persons aged 65 years and older with T2DM were included. The methodological quality of studies was assessed.Results: Twenty-one eligible studies were reviewed, only six studies were rated as good quality and only one study specifically targeted persons aged 65 years and older. Personalised coaching, goal setting, peer support groups, use of technology and physical activity monitors were proven to increase the level of physical activity. Incorporation of health behaviour theories and follow-up supports also were successful strategies. However, the methodological quality and type of interventions promoting physical activity of the included studies in this review varied widely across the eligible studies.Conclusion: Strategies that increased level of physical activity in persons with T2DM are evident but most studies focused on middle-aged persons and there was a lack of well-designed trials. Hence, more studies of satisfactory methodological quality with interventions promoting physical activity in older people are required.

  9. Review of the Physical Science Facility Stack Air Sampling Probe Locations

    Energy Technology Data Exchange (ETDEWEB)

    Glissmeyer, John A.

    2007-09-30

    This letter report reviews compliance of the current design of the Physical Science Facility (PSF) stack air sampling locations with the ANSI/HPS N13.1-1999 standard. The review was based on performance criteria used for locating air sampling probes, the design documents provided and available information on systems previously tested for compliance with the criteria. Recommendations are presented for ways to bring the design into compliance with the requirements for the sampling probe placement.

  10. Direct access compared with referred physical therapy episodes of care: a systematic review.

    Science.gov (United States)

    Ojha, Heidi A; Snyder, Rachel S; Davenport, Todd E

    2014-01-01

    Evidence suggests that physical therapy through direct access may help decrease costs and improve patient outcomes compared with physical therapy by physician referral. The purpose of this study was to conduct a systematic review of the literature on patients with musculoskeletal injuries and compare health care costs and patient outcomes in episodes of physical therapy by direct access compared with referred physical therapy. Ovid MEDLINE, CINAHL (EBSCO), Web of Science, and PEDro were searched using terms related to physical therapy and direct access. Included articles were hand searched for additional references. Included studies compared data from physical therapy by direct access with physical therapy by physician referral, studying cost, outcomes, or harm. The studies were appraised using the Centre for Evidence-Based Medicine (CEBM) levels of evidence criteria and assigned a methodological score. Of the 1,501 articles that were screened, 8 articles at levels 3 to 4 on the CEBM scale were included. There were statistically significant and clinically meaningful findings across studies that satisfaction and outcomes were superior, and numbers of physical therapy visits, imaging ordered, medications prescribed, and additional non-physical therapy appointments were less in cohorts receiving physical therapy by direct access compared with referred episodes of care. There was no evidence for harm. There is evidence across level 3 and 4 studies (grade B to C CEBM level of recommendation) that physical therapy by direct access compared with referred episodes of care is associated with improved patient outcomes and decreased costs. Primary limitations were lack of group randomization, potential for selection bias, and limited generalizability. Physical therapy by way of direct access may contain health care costs and promote high-quality health care. Third-party payers should consider paying for physical therapy by direct access to decrease health care costs and

  11. Mental health and physical activity in women with polycystic ovary syndrome: a brief review.

    Science.gov (United States)

    Conte, Francesca; Banting, Lauren; Teede, Helena J; Stepto, Nigel K

    2015-04-01

    This review was designed to consider the available literature concerning mental health and physical activity in women with polycystic ovary syndrome (PCOS). A systematic approach was taken and two electronic databases (PubMed and EBSCO Research articles published between 1970 and 2013) were searched in 2013 to inform a narrative review. Inclusion criteria encompassed requirements for the research to involve a physical activity intervention and assessment of mental health outcomes in women with PCOS. Seven articles considered mental health outcomes and physical activity interventions for women with PCOS. The results demonstrated positive outcomes following physical activity intervention for health-related quality of life, depression, and anxiety. Only one paper reported the independent effects of physical activity on mental health. All other interventions included multi-factor lifestyle interventions or did not establish a control group. Physical activity is likely to be beneficial to the mental health of women with PCOS; however, more research is required to establish the nature of the relationship between physical activity and mental health outcomes.

  12. The Clinical anatomy of the physical examination of the abdomen: A comprehensive review.

    Science.gov (United States)

    Bilal, Muhammad; Voin, Vlad; Topale, Nitsa; Iwanaga, Joe; Loukas, Marios; Tubbs, R Shane

    2017-04-01

    Physical examination of the abdomen is an essential skill. Knowledge of its clinical anatomy and application is vital for making diagnoses. Misinterpretation of anatomy during examination can have serious consequences. This review addresses understanding of the anatomy, methodology, and complications of abdominal physical examination. It includes particular reference to modern technology and investigations. Physical examination is performed for diagnostic purposes. However, the art of physical examination is declining as more and more clinicians rely on newer technology. This can have regrettable consequences: negligence, waste of time and resources, and deterioration of clinical skills. With a sound knowledge of clinical anatomy, and realization of the importance of physical examination of the abdomen, clinician, and patients alike can benefit. Clin. Anat. 30:352-356, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  13. WE-E-218-01: Writing and Reviewing Papers in Medical Physics.

    Science.gov (United States)

    Hendee, W; Slattery, P; Rogers, D; Karellas, A

    2012-06-01

    There is an art to writing a scientific paper so that it communicates accurately, succinctly, and comprehensively. Developing this art comes with experience, and sharing that experience with younger physicists is an obligation of senior scientists, especially those with editorial responsibilities for the journal. In this workshop, the preparation of a scientific manuscript will be dissected so participants can appreciate how each part is developed and then assembled into a complete paper. Then the review process for the paper will be discussed, including how to examine a paper and write an insightful and constructive review. Finally, we will consider the challenge of accommodating the concerns and recommendations of a reviewer in preparing a revision of the paper. A second feature of the workshop will be a discussion of the process of electronic submission of a paper for consideration by Medical Physics. The web-based PeerX-Press engine for manuscript submission and management will be examined, with attention to special features such as epaps and line-referencing. Finally, new features of Medical Physics will be explained, such as Vision 20/20 manuscripts, Physics Letters and the standardized formatting of book reviews. 1. Improve the participants' abilities to write a scientific manuscript. 2. Understand the review process for Medical Physics manuscripts and how to participate in and benefit from it. 3. Appreciate the many features of the PeerX-Press electronic management process for Medical Physics manuscripts. 4. Develop a knowledge of new features of Medical Physics. © 2012 American Association of Physicists in Medicine.

  14. Physical articular examination in the activity of rheumatoid arthritis: a systematic review of the literature : Systematic review of the literature regarding physical examination in rheumatoid arthritis.

    Science.gov (United States)

    Medina, Yimy F; Ruíz-Gaviria, Rafael Eduardo; Buitrago-Lopez, Adriana; Villota, Catalina

    2018-02-20

    To summarize evidence concerning the articular examination needed to determine rheumatoid arthritis (RA) activity (follow-up or control) via a systematic review. A search of Medline, Embase, Lilacs, SciELO, the Web of Science, the National Technical Reports Library, and the reference lists of relevant studies through March 2017 was conducted using a systematic methodology to identify studies of patients with RA older than 18 years in which a detailed description of the physical examination or a description of the components of the articular examination was provided. Of 8322 references, 74 studies were included according to the selection criteria, and 6 references were ultimately included at the end of the review. Most of the included studies (n = 5) were associated with a moderate risk of bias. There was great variability among the studies and the articular examination methods used. Some studies presented the examination with a complete specification of the technique (n = 2), the consensus of rheumatologists (n = 2), or training through audiovisual materials and face-to-face courses (n = 2), but none of the studies explicitly showed the technique by which the physical examination was performed. Despite the importance of the clinical evaluation and physical examination of patients with RA for diagnosis, prognosis, clinimetrics, and follow-up, evidence concerning how to perform the articular examination is scarce.

  15. The Benefits of Active Video Games for Educational and Physical Activity Approaches: A Systematic Review

    Directory of Open Access Journals (Sweden)

    Carlos Merino-Campos

    2016-07-01

    Full Text Available This article sets out to conduct a systematic review of the current literature on active video games as potential educational tools for physical education or physical activity. To begin with, research on active video games for educational and physical purposes has been examined with the purpose of verifying improvement of attitudes, intellectual skills, knowledge, motor skills and physical properties associated with physical activity and physical education. A second aim will be to determine the effectiveness of active video games compared with traditional approaches to physical activity. From this perspective, a systematic literature search from relevant international databases was conducted from January to July 2015 in order to find papers published in journals or conference proceedings from January 2010 onwards. Then, 2648 references were identified in database searches and 100 of these papers met the inclusion criteria. Two main conclusions are to be drawn from this research. Firstly, controlled studies demonstrate that active video games increase capacities in relation to physical activity and education. Secondly, Research also shows that physical activity interventions designed and measured using behavioural theories are more likely to be successful in comparison with traditional exercise activities.

  16. [Systematized physical activity and cognitive performance in elderly with Alzheimer's dementia: a systematic review].

    Science.gov (United States)

    Coelho, Flávia Gomes de Melo; Santos-Galduroz, Ruth Ferreira; Gobbi, Sebastião; Stella, Florindo

    2009-06-01

    Despite the growing evidence of the benefits of physical exercise for cognition, there is a controversy about the systematic practice of physical activity in patients with Alzheimer's disease. Therefore, the objective of this study was to procedure a systematic review of studies that analyzed the effect of systematized physical activity on cognitive performance in elderly individuals with Alzheimer's disease. We conducted a search in PsycINFO, Biological Abstracts, Medline, Web of Science, Physical Education and SPORTDiscus Index from 1990 to 2008, using the following keywords: 'physical activity', 'physical therapy', 'exercise', 'fitness', 'aerobic', 'strength', 'intervention', 'cognition', 'cognitive performance', 'Alzheimer's disease', 'Alzheimer's dementia', 'Alzheimer's', and cross-references of selected articles. There were found eight studies that met inclusion criteria adopted for the present work. These studies showed that systematized physical activity contributed to at least improve temporarily some cognitive functions of patients with Alzheimer's disease, particularly, attention, executive functions and language. Unable to establish a protocol of recommendations about the type and intensity of systematized physical activity required to produce benefits in cognitive functioning. However, the practice of regular systematized physical activity appears to contribute to the preservation or improvement of cognitive functions in patients with Alzheimer's disease.

  17. Increasing Physical Activity and Participation in People With Multiple Sclerosis: A Review.

    Science.gov (United States)

    Backus, Deborah

    2016-09-01

    Multiple sclerosis (MS) is a chronic progressive disease of the central nervous system (CNS) affecting >2.5 million people worldwide. Damage to neurons in the CNS causes various sensorimotor and cognitive symptoms, such as fatigue, pain, spasticity, memory deficits, and impairment of mobility. Until the late 1990s, it was believed that symptoms of MS would be worsened with physical exertion and people with MS were encouraged to limit physical activity and exertion. Not only has emerging evidence suggested that physical activity, including exercise, is safe for people with MS, there is also evidence that at least some of the disability that occurs after MS is due to secondary deconditioning from the sedentary lifestyle adopted because of the symptoms of MS, not just CNS damage alone. Therefore, not only is physical activity safe, it is also required for maintaining function and health in people with MS. The purpose of this article is to review the unique physical and social barriers to physical activity in people with MS, including those with moderate to severe disability who use a wheelchair or scooter for mobility. We will discuss how existing guidelines for physical activity may not meet the needs of people with MS and present evidence-based considerations for promoting physical activity in people with MS. Ultimately, the goal is to overcome the barriers to physical activity and improve health, participation, and quality of life in people with MS. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  18. A systematic review of intervention effects on potential mediators of children’s physical activity

    Directory of Open Access Journals (Sweden)

    Brown Helen

    2013-02-01

    Full Text Available Abstract Background Many interventions aiming to increase children’s physical activity have been developed and implemented in a variety of settings, and these interventions have previously been reviewed; however the focus of these reviews tends to be on the intervention effects on physical activity outcomes without consideration of the reasons and pathways leading to intervention success or otherwise. To systematically review the efficacy of physical activity interventions targeting 5-12 year old children on potential mediators and, where possible, to calculate the size of the intervention effect on the potential mediator. Methods A systematic search identified intervention studies that reported outcomes on potential mediators of physical activity among 5-12 year old children. Original research articles published between 1985 and April 2012 were reviewed. Results Eighteen potential mediators were identified from 31 studies. Positive effects on cognitive/psychological potential mediators were reported in 15 out of 31 studies. Positive effects on social environmental potential mediators were reported in three out of seven studies, and no effects on the physical environment were reported. Although no studies were identified that performed a mediating analysis, 33 positive intervention effects were found on targeted potential mediators (with effect sizes ranging from small to large and 73% of the time a positive effect on the physical activity outcome was reported. Conclusions Many studies have reported null intervention effects on potential mediators of children’s physical activity; however, it is important that intervention studies statistically examine the mediating effects of interventions so the most effective strategies can be implemented in future programs.

  19. The rise and fall of Australian physical activity policy 1996 – 2006: a national review framed in an international context

    OpenAIRE

    Bellew, Bill; Schöeppe, Stephanie; Bull, Fiona C; Bauman, Adrian

    2008-01-01

    Background This paper provides an historical review of physical activity policy development in Australia for a period spanning a decade since the release of the US Surgeon General's Report on Physical Activity and Health in 1996 and including the 2004 WHO Global Strategy on Diet, Physical Activity and Health. Using our definition of 'HARDWIRED' policy criteria, this Australian review is compared with an international perspective of countries with established national physical activity policie...

  20. PERSPECTIVES OF MOLIBDENUM CONTAINING MATERIALS APPLICATION FOR ALLOYING OF IRONCARBON ALLOYS DURING MANUFACTURING OF CRITICAL CASTINGS

    Directory of Open Access Journals (Sweden)

    A. G. Slutsky

    2015-01-01

    Full Text Available Motor is one of most important part of automobile determine its economical effectiveness of usage. On the other hand, sleeves, pistons and rings are crucible parts as they determine the service life of a motor. These parts are producing in big scale – dozens of millions pieces. Increase of cylinder sleeves physical-mechanical properties results in prolongation of motor service life and improvement of motor’s characteristics. Nowadays low alloyed cast irons with perlite structure are used to manufacture motor’s sleeves. For alloying purposes such traditional elements as Cr, Ni, Cu, and V are applied. But it is interesting to use molybdenum for cast iron alloying. It is known that alloying of alloys allows considerable increasing of consumption properties of castings. But in spite of advantages of alloys alloying the increase of molybdenum containing iron-carbon alloys production is restricted by economical reasons – high cost of alloying additions. Expenditures on alloying additions can be reduced by the application cheap secondary alloys in the charge. So, the present paper is devoted to investigation of alloying peculiarities during the treatment of ferrous alloys with molybdenum applying different initial materials.