Synthesis of Uranium nitride powders using metal uranium powders

International Nuclear Information System (INIS)

Yang, Jae Ho; Kim, Dong Joo; Oh, Jang Soo; Rhee, Young Woo; Kim, Jong Hun; Kim, Keon Sik

2012-01-01

Uranium nitride (UN) is a potential fuel material for advanced nuclear reactors because of their high fuel density, high thermal conductivity, high melting temperature, and considerable breeding capability in LWRs. Uranium nitride powders can be fabricated by a carbothermic reduction of the oxide powders, or the nitriding of metal uranium. The carbothermic reduction has an advantage in the production of fine powders. However it has many drawbacks such as an inevitable engagement of impurities, process burden, and difficulties in reusing of expensive N 15 gas. Manufacturing concerns issued in the carbothermic reduction process can be solved by changing the starting materials from oxide powder to metals. However, in nitriding process of metal, it is difficult to obtain fine nitride powders because metal uranium is usually fabricated in the form of bulk ingots. In this study, a simple reaction method was tested to fabricate uranium nitride powders directly from uranium metal powders. We fabricated uranium metal spherical powder and flake using a centrifugal atomization method. The nitride powders were obtained by thermal treating those metal particles under nitrogen containing gas. We investigated the phase and morphology evolutions of powders during the nitriding process. A phase analysis of nitride powders was also a part of the present work

Contribution to the study of the geophysical behaviour of lead-210 by application of alpha spectrometry; Contribution a l'etude du comportement geophysique du plomb 210 par application de la spectrometrie alpha

Energy Technology Data Exchange (ETDEWEB)

Nezami, M. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1965-06-01

A study of the changes in the lead-210 contents of rain-water and of water produced by melting polar ice has required the development of a method for dosing lead-210, an {alpha} emitter. This method is 40 times more sensitive than that which measures the lead-210 by bismuth-210, a ({beta} emitter. The first part of the report presents the study of a spectrometry using semiconductor detectors; a catalogue of a spectra shows the advantages of this method. In the second part will be found at first a new chemical separation method for polonium-210 and the results obtained with this method. The main results obtained on the geophysical behaviour of lead-210 are the following: - the monthly lead-210 and polonium-210 contents in rain water are approximately constant with time. - in the Gif-sur-Yvette region, the clean-up by 'dry fall-out' can attain 40 to 50 per cent of the total fall-out. - a study of Antarctic ice samples makes it possible to determine an annual accumulation rate equivalent to 13.8 cm of water and to show discrepancies in the periodic concentrations which correspond to the latest maxima of solar activity. - a balance is drawn up between the radon produced by the continents and the lead-210 fall-out. (author) [French] Une etude sur les variations de la teneur en plomb 210 des eaux de pluie et des eaux de fusion des glaces polaires a necessite la mise au point d'une methode de dosage du plomb 210 emetteur {alpha}. Cette methode permet d'obtenir une sensibilite quarante fois superieure a celle dosant le plomb 210 par le bismuth 210 emetteur {beta}. La premiere partie du travail presente l'etude de la spectrometrie {alpha} par detecteur a semiconducteurs, un catalogue de spectres {alpha} met en evidence les avantages de cette methode. Dans la deuxieme partie on trouvera en premier lieu une nouvelle methode chimique de separation du polonium 210 ainsi que les resultats obtenus grace a cette methode. Les principaux resultats sur le

98 Etude Comparative du Systeme Phonematique et Tonal des ...

African Journals Online (AJOL)

98. Etude Comparative du Systeme Phonematique et Tonal des. Deux Parlers: Le Yoruba du Nigeria et L'itsa Parle en. Republique du Benin. Ajani Akinwumi Lateef et Ayuba G. Ajibabi http://dx.doi./org/10.4314/ujah.v18i3.5. Résume. En ce début de l'époque ou la mondialisation et la coexistence des peuples dans le ...

Magnetic resonance studies of solid polymers; Etude des polymeres solides par resonance magnetique

Energy Technology Data Exchange (ETDEWEB)

Lenk, R [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

1969-07-01

This paper is a review of the application of nuclear magnetic resonance (NMR) to solid polymers. In the first, theoretical part, the elements of the theory of NMR, which are necessary for the study of the properties of solid polymers are discussed: the moments method, nuclear relaxation and the distribution of correlation times. In the second part the experimental results are presented. (author) [French] Cette etude est une recherche bibliographique sur l'application de la resonance magnetique nucleaire (RMN) aux polymeres solides. Dans la premiere partie theorique on discute les elements de la theorie de RMN, necessaires pour l'etude des proprietes des polymeres solides: la methode des moments, la relaxation nucleaire et la distribution des temps de correlation. La deuxieme partie presente les resultats des experiences. (auteur)

Generalities on the dynamic behaviour of rapid reactors. Preliminary studies on Rapsodie; Generalites sur le comportement dynamique des piles rapides. Etudes preliminaires de rapsodie

Energy Technology Data Exchange (ETDEWEB)

Campan, J L; Chaumont, J P; Clauzon, P P; Ghesquiere, G; Leduc, J; Schmitt, A P; Zaleski, C P [Commissariat a l' Energie Atomique, Cadarache (France). Centre d' Etudes Nucleaires

1963-07-01

The study of the dynamic behaviour of fast reactors may be divided into three section: 1. Stability studies around equilibrium power only the linear case was examining. S. Transient studies in the case of usual reactor operation (shut down, scram, etc.) with thermal shocks evaluation, for instance. 3. Explosion studies, for the maximum credible accidents. This report presents the status of the studies performed at the 'Physics Research Department' at Cadarache. Methods used are detailed and illustrated with the results obtained on a preliminary metallic core of the Rapsodie Reactor. (authors) [French] Le comportement dynamique des piles rapides, se presente tout naturellement sous trois aspects: 1. Etude de stabilite autour d'un regime d'equilibre (nous nous sommes bornes ici au cas lineaire). 2. Etude de regimes transitoires lors des operations normales de pile (arret, arret d'urgence, etc.) avec evaluation des chocs thermiques par exemple. 3. Etude des regimes transitoires de caractere explosif lors des accidents les plus graves possibles. Ce rapport presente l'etat des etudes a la date du 20 decembre 1961 a la Section d'Etudes de Piles Rapides a CADARACHE. Les methodes employees ont ete detaillees et illustrees a partir des resultats obtenus sur une premiere version 'combustible metallique' de Rapsodie. (auteurs)

Solid-assisted melt disintegration (SAMD), a novel technique for metal powder production

International Nuclear Information System (INIS)

Akhlaghi, F.; Esfandiari, H.

2007-01-01

A new process termed 'solid-assisted melt disintegration (SAMD)' has been developed for the preparation of aluminum alloy powder particles. The method consists of introducing and mixing a specified amount of as-received alumina particles (in the range of +700 to 500 μm) in A356 aluminum melt at the temperature of 715 deg. C. Melt disintegration occurs in 10 min by kinetic energy transfer from a rotating impeller (450 rpm) to the metal via the solid atomizing medium (alumina particles). The resulting mixture of aluminum droplets and alumina particles was cooled in air and screened through 300 μm sieve to separate alumina from solidified aluminum powder particles. A356 aluminum alloy was also gas atomized by using a free-fall atomizer operating by nitrogen gas at the pressure of 1.1 MPa and the sub-300 μm of the produced powder was used as a base of comparison. The SAMD produced powders of diameter above 53 μm were mostly spherical while powders less than 53 μm showed various elongated shapes. No evidence was found for satelliting of small particles on to large ones or agglomerated particles. While gas atomized particles in the +53 μm sieve size range showed some signs of porosity, the SAMD particles were dense and did not show any signs of internal porosity in any of the sieve fractions investigated. Comparison of the microstructure of the SAMD and gas-atomized powders revealed that for the same size powder of A356 alloy, the former exhibited a coarser microstructure as a result of a slower cooling rate

The formation of scientists and technicians at the 'Centre d'Etudes Nucleaires' at Saclay; Formation des scientifiques et des techniciens au Centre d'Etudes Nucleaires de Saclay

Energy Technology Data Exchange (ETDEWEB)

Debiesse, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1958-07-01

The considerable needs in research workers and scientists which are asked by the nuclear energy obliged the Commissariat a l'Energie atomique to deal with a particular effort to increase the quantitative and qualitative formation of scientists. Most various ways have been used. 1- A National Institute of Nuclear Sciences and Nuclear Techniques was created, by a joint decree of the Prime Minister and the Minister for National Education (june 18, 1957). This Institute of Higher Teaching (250 students) indulges in the following matters: atomic engineering, quantum mechanics, theory and technic of particle accelerators, special metallurgy, radiobiology, thermic and mechanics of fluids. 2- An associated centre of the 'Conservatoire National des Arts et Metiers' waeated (200 students) for technical assistants, drawers, etc. 3- In contribution with both electronic industry and Ministry of Work, the Centre d'Etudes Nucleaires contributes to an accelerated formation of technical assistants into Professional Centres. Conclusion: Training of scientists and research workers is one of the most important activities of the Centre d'Etudes Nucleaires de Saclay. Without losing its technical efficiency, it has supplied and varied means adapted to the various purposes that we shall reach. (author)Fren. [French] Les besoins considerables actuels et previsibles en chercheurs et scientifiques necessites par l'avevement de l'energie nucleaire imposaient au Commissariat a I'Energie atomique un effort particulier pour augmenter la formation quantitative et qualitative des scientifiques. Les moyens les plus divers ont ete mis en oeuvre: 1- Creation de l'Institut National des Sciences et Techniques Nucleaires par decret de la Presidence du Conseil et de l'Education Nationale en date du 18.6.57. Cet Institut d'Enseignement Superieur (250 etudiants) donne des cours en: genie atomique, mecanique quantique, theorie et technique des Accelerateurs de particules, metallurgie speciale, radiobiologie

Etude de la qualité physico-chimique et biologique des eaux du ...

African Journals Online (AJOL)

Etude de la qualité physico-chimique et biologique des eaux du fleuve Niger à Niamey. ... le récepteur principal des rejets d'eaux usées de la ville de Niamey, capital du ... La description de ces taxons montre une variation de la structure des ...

New Strategies for Powder Compaction in Powder-based Rapid Prototyping Techniques

OpenAIRE

Budding, A.; Vaneker, T.H.J.

2013-01-01

In powder-based rapid prototyping techniques, powder compaction is used to create thin layers of fine powder that are locally bonded. By stacking these layers of locally bonded material, an object is made. The compaction of thin layers of powder mater ials is of interest for a wide range of applications, but this study solely focuses on the application for powder -based three-dimensional printing (e.g. SLS, 3DP). This research is primarily interested in powder compaction for creating membrane...

Corrosion-resistant powder-metallurgy stainless steel powders and compacts therefrom

International Nuclear Information System (INIS)

Klar, E.; Ro, D.H.; Whitman, C.I.

1980-01-01

Disclosed is a process for improving the corrosion resistance of a stainless steel powder or compact thereof wherein the powder is produced by atomizing a melt of metals in an oxidizing environment whereby the resulting stainless steel powder is surface-enriched in silicon oxides. The process comprises adding an effective proportion of modifier metal to the melt prior to the atomization, the modifier metal selected from the group consisting of tin, aluminum, lead, zinc, magnesium, rare earth metals and like metals capable of enrichment about the surface of the resulting atomized stainless steel powder and effective under reductive sintering conditions in the depletion of the silicon oxides about the surface; and sintering the resulting atomized powder or a compact thereof under reducing conditions, the sintered powder or compact thereof being depleted in the silicon oxides and the corrosion resistance of the powder or compact thereof being improved thereby

Magnetic study of solid uranium-fluorine complexes; Contribution a l'etude magnetique de composes fluores solides de l'uranium

Energy Technology Data Exchange (ETDEWEB)

Dianoux, A J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1969-06-01

A study of the magnetic susceptibility of uranium V fluorine complexes and of the magnetic resonance of fluorine atoms in uranium VI fluorine complexes has made it possible to put forward a structural model for these compounds for which it is impossible, because of the lack of suitable single crystals for X-ray diffraction work, to deduce the exact position of the fluorine atoms. It is shown that it is difficult to interpret the paramagnetism of uranium fluorides, because the uranium ions are in low-symmetry sites. A theoretical study of the magnetism of the U{sup V} ion in complex fluorides of the type M{sub 3}UF{sub 8} (M = NH{sub 4}, Na, Rb, Cs) leads to an interpretation based on a trigonal deformation of the eight fluorine atom structure surrounding the uranium atom. By applying a Hamiltonian spin formalism and making a systematic use of group theory, it is possible to present the susceptibility calculations very concisely. Study of the resonance and of the relaxation of the fluorine atoms in powdered uranium VI complex fluorides suggests a structural model in the case of NaUF{sub 7}. It is shown that the shape of the magnetic resonance absorption lines is strongly affected by the presence of large anisotropic chemical shifts. In the model proposed here, six fluorine atoms are linked to the uranium, atom by strongly covalent bonds in a deformed UF{sub 6} octahedral structure; the seventh fluorine atom remains ionic. The occurrence of a rotational movement of the octahedron is confirmed by a study of the longitudinal relaxation of the fluorine atoms, the activation energy being 0.46 eV. (author) [French] L'etude de la susceptibilite magnetique de complexes fluores d'uranium V et la resonance magnetique des fluors dans des complexes fluores d'uranium VI permettent de proposer un modele structural pour ces composes, ou la diffraction des rayons X, en l'absence de monocristaux convenables, est incapable de preciser la position des atomes de fluor. Nous montrons

Light extinction in metallic powder beds: Correlation with powder structure

International Nuclear Information System (INIS)

Rombouts, M.; Froyen, L.; Gusarov, A.V.; Bentefour, E.H.; Glorieux, C.

2005-01-01

A theoretical correlation between the effective extinction coefficient, the specific surface area, and the chord length distribution of powder beds is verified experimentally. The investigated powder beds consist of metallic particles of several tens of microns. The effective extinction coefficients are measured by a light-transmission technique at a wavelength of 540 nm. The powder structure is characterized by a quantitative image analysis of powder bed cross sections resulting in two-point correlation functions and chord length distributions. The specific surface area of the powders is estimated by laser-diffraction particle-size analysis and by the two-point correlation function. The theoretically predicted tendency of increasing extinction coefficient with specific surface area per unit void volume is confirmed by the experiments. However, a significant quantitative discrepancy is found for several powders. No clear correlation of the extinction coefficient with the powder material and particle size, and morphology is revealed, which is in line with the assumption of geometrical optics

186 Etude théorique du transport électronique par la simulation ...

African Journals Online (AJOL)

youness

Choukria SAYAH et al. 186. Etude théorique du ... For that we carried out the microscopic simulations, based on the Monte. Carlo method. ... intervalles, piezoelectric as well as the interactions of alloy and on ionized impurities. ..... SAYA et al. 198. [5] - R. W. Hockney, J. W. Eastwood, "Computer simulation using particles",.

New Strategies for Powder Compaction in Powder-based Rapid Prototyping Techniques

NARCIS (Netherlands)

Budding, A.; Vaneker, Thomas H.J.

2013-01-01

In powder-based rapid prototyping techniques, powder compaction is used to create thin layers of fine powder that are locally bonded. By stacking these layers of locally bonded material, an object is made. The compaction of thin layers of powder mater ials is of interest for a wide range of

Falls following discharge after an in-hospital fall

Directory of Open Access Journals (Sweden)

Kessler Lori A

2009-12-01

Full Text Available Abstract Background Falls are among the most common adverse events reported in hospitalized patients. While there is a growing body of literature on fall prevention in the hospital, the data examining the fall rate and risk factors for falls in the immediate post-hospitalization period has not been well described. The objectives of the present study were to determine the fall rate of in-hospital fallers at home and to explore the risk factors for falls during the immediate post-hospitalization period. Methods We identified patients who sustained a fall on one of 16 medical/surgical nursing units during an inpatient admission to an urban community teaching hospital. After discharge, falls were ascertained using weekly telephone surveillance for 4 weeks post-discharge. Patients were followed until death, loss to follow up or end of study (four weeks. Time spent rehospitalized or institutionalized was censored in rate calculations. Results Of 95 hospitalized patients who fell during recruitment, 65 (68% met inclusion criteria and agreed to participate. These subjects contributed 1498 person-days to the study (mean duration of follow-up = 23 days. Seventy-five percent were African-American and 43% were women. Sixteen patients (25% had multiple falls during hospitalization and 23 patients (35% suffered a fall-related injury during hospitalization. Nineteen patients (29% experienced 38 falls at their homes, yielding a fall rate of 25.4/1,000 person-days (95% CI: 17.3-33.4. Twenty-three patients (35% were readmitted and 3(5% died. One patient experienced a hip fracture. In exploratory univariate analysis, persons who were likely to fall at home were those who sustained multiple falls in the hospital (p = 0.008. Conclusion Patients who fall during hospitalization, especially on more than one occasion, are at high risk for falling at home following hospital discharge. Interventions to reduce falls would be appropriate to test in this high-risk population.

Aluminum powder metallurgy processing

Energy Technology Data Exchange (ETDEWEB)

Flumerfelt, J.F.

1999-02-12

The objective of this dissertation is to explore the hypothesis that there is a strong linkage between gas atomization processing conditions, as-atomized aluminum powder characteristics, and the consolidation methodology required to make components from aluminum powder. The hypothesis was tested with pure aluminum powders produced by commercial air atomization, commercial inert gas atomization, and gas atomization reaction synthesis (GARS). A comparison of the GARS aluminum powders with the commercial aluminum powders showed the former to exhibit superior powder characteristics. The powders were compared in terms of size and shape, bulk chemistry, surface oxide chemistry and structure, and oxide film thickness. Minimum explosive concentration measurements assessed the dependence of explosibility hazard on surface area, oxide film thickness, and gas atomization processing conditions. The GARS aluminum powders were exposed to different relative humidity levels, demonstrating the effect of atmospheric conditions on post-atomization processing conditions. The GARS aluminum powders were exposed to different relative humidity levels, demonstrating the effect of atmospheric conditions on post-atomization oxidation of aluminum powder. An Al-Ti-Y GARS alloy exposed in ambient air at different temperatures revealed the effect of reactive alloy elements on post-atomization powder oxidation. The pure aluminum powders were consolidated by two different routes, a conventional consolidation process for fabricating aerospace components with aluminum powder and a proposed alternative. The consolidation procedures were compared by evaluating the consolidated microstructures and the corresponding mechanical properties. A low temperature solid state sintering experiment demonstrated that tap densified GARS aluminum powders can form sintering necks between contacting powder particles, unlike the total resistance to sintering of commercial air atomization aluminum powder.

Women's perspectives on falls and fall prevention during pregnancy.

Science.gov (United States)

Brewin, Dorothy; Naninni, Angela

2014-01-01

Falls are the leading cause of unintentional injury in women. During pregnancy, even a minor fall can result in adverse consequences. Evidence to inform effective and developmentally appropriate pregnancy fall prevention programs is lacking. Early research on pregnancy fall prevention suggests that exercise may reduce falls. However, acceptability and effectiveness of pregnancy fall prevention programs are untested. To better understand postpartum women's perspective and preferences on fall prevention strategies during pregnancy to formulate an intervention. Focus groups and individual interviews were conducted with 31 postpartum women using descriptive qualitative methodology. Discussion of falls during pregnancy and fall prevention strategies was guided by a focus group protocol and enhanced by 1- to 3-minute videos on proposed interventions. Focus groups were audio recorded, transcribed, and analyzed using NVivo 10 software. Emerging themes were environmental circumstances and physical changes of pregnancy leading to a fall, prevention strategies, barriers, safety concerns, and marketing a fall prevention program. Wet surfaces and inappropriate footwear commonly contributed to falls. Women preferred direct provider counseling and programs including yoga and Pilates. Fall prevention strategies tailored to pregnant women are needed. Perspectives of postpartum women support fall prevention through provider counseling and individual or supervised exercise programs.

152 Etude de cas sur l'impact des amendements organiques vis-à ...

African Journals Online (AJOL)

john mukalay

Etude de cas sur l'impact des amendements organiques vis-à-vis de la salinité en culture de bananier. Michel Mazinga KWEY1, Séverin Kalala BANZE2 et John Banza MUKALAY2*. 1Laboratoire des cultures in vitro, Département de phytotechnie, Faculté des sciences agronomiques,. Université de Lubumbashi, BP 1825, ...

Etude comparative de la flore aux abords des cours d'eau dans les ...

African Journals Online (AJOL)

Etude comparative de la flore aux abords des cours d'eau dans les zones hypo et hyper endémiques d'ulcère de Buruli en Côte d'Ivoire. C. Cisse Boni, E. Ehouman, D. Soro, M.W. Kone, A. Bakayoko, F. Dembele, K. Bauthire, M Dosso ...

Study of electron groupings in the Saclay linear accelerator; Etude du groupement des electrons dans l'accelerateur lineaire de Saclay

Energy Technology Data Exchange (ETDEWEB)

Bergere, R; Veyssiere, A; Beil, H [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1965-07-01

The classical theory of the linear accelerator buncher does not fit the experimental measurements of the shape of the bunch of electrons performed at Saclay by the method of the energy spectrum. If the spurious effect of the mode converter at the input of the linac is taken into account the theory can fit the experimental results and also explain the variations of the phase of the bunch on the accelerating sine wave. (authors) [French] Une etude classique du groupeur en tete de l'Accelerateur Lineaire de Saclav conduit a des resultats incompatibles avec les resultats experimentaux obtenus sur le groupement des electrons par l'etude du spectre des frequences rayonnees par le faisceau d'electrons ou par l'etude des spectres en energie. Par contre si l'effet parasite du convertisseur de mode a l'entree de l'accelerateur est pris en consideration les resultats theoriques coincident bien avec les resultats experimentaux et permettent en outre d'expliquer les variations du calage en phase des paquets elementaires d'electrons. (auteurs)

Relationship between subjective fall risk assessment and falls and fall-related fractures in frail elderly people.

Science.gov (United States)

Shimada, Hiroyuki; Suzukawa, Megumi; Ishizaki, Tatsuro; Kobayashi, Kumiko; Kim, Hunkyung; Suzuki, Takao

2011-08-12

Objective measurements can be used to identify people with risks of falls, but many frail elderly adults cannot complete physical performance tests. The study examined the relationship between a subjective risk rating of specific tasks (SRRST) to screen for fall risks and falls and fall-related fractures in frail elderly people. The SRRST was investigated in 5,062 individuals aged 65 years or older who were utilized day-care services. The SRRST comprised 7 dichotomous questions to screen for fall risks during movements and behaviours such as walking, transferring, and wandering. The history of falls and fall-related fractures during the previous year was reported by participants or determined from an interview with the participant's family and care staff. All SRRST items showed significant differences between the participants with and without falls and fall-related fractures. In multiple logistic regression analysis adjusted for age, sex, diseases, and behavioural variables, the SRRST score was independently associated with history of falls and fractures. Odds ratios for those in the high-risk SRRST group (≥ 5 points) compared with the no risk SRRST group (0 point) were 6.15 (p fall, 15.04 (p falls, and 5.05 (p fall-related fractures. The results remained essentially unchanged in subgroup analysis accounting for locomotion status. These results suggest that subjective ratings by care staff can be utilized to determine the risks of falls and fall-related fractures in the frail elderly, however, these preliminary results require confirmation in further prospective research.

Magnetic study of solid uranium-fluorine complexes; Contribution a l'etude magnetique de composes fluores solides de l'uranium

Energy Technology Data Exchange (ETDEWEB)

Dianoux, A.J. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1969-06-01

A study of the magnetic susceptibility of uranium V fluorine complexes and of the magnetic resonance of fluorine atoms in uranium VI fluorine complexes has made it possible to put forward a structural model for these compounds for which it is impossible, because of the lack of suitable single crystals for X-ray diffraction work, to deduce the exact position of the fluorine atoms. It is shown that it is difficult to interpret the paramagnetism of uranium fluorides, because the uranium ions are in low-symmetry sites. A theoretical study of the magnetism of the U{sup V} ion in complex fluorides of the type M{sub 3}UF{sub 8} (M = NH{sub 4}, Na, Rb, Cs) leads to an interpretation based on a trigonal deformation of the eight fluorine atom structure surrounding the uranium atom. By applying a Hamiltonian spin formalism and making a systematic use of group theory, it is possible to present the susceptibility calculations very concisely. Study of the resonance and of the relaxation of the fluorine atoms in powdered uranium VI complex fluorides suggests a structural model in the case of NaUF{sub 7}. It is shown that the shape of the magnetic resonance absorption lines is strongly affected by the presence of large anisotropic chemical shifts. In the model proposed here, six fluorine atoms are linked to the uranium, atom by strongly covalent bonds in a deformed UF{sub 6} octahedral structure; the seventh fluorine atom remains ionic. The occurrence of a rotational movement of the octahedron is confirmed by a study of the longitudinal relaxation of the fluorine atoms, the activation energy being 0.46 eV. (author) [French] L'etude de la susceptibilite magnetique de complexes fluores d'uranium V et la resonance magnetique des fluors dans des complexes fluores d'uranium VI permettent de proposer un modele structural pour ces composes, ou la diffraction des rayons X, en l'absence de monocristaux convenables, est incapable de preciser la position des atomes de

Spherical rhenium metal powder

International Nuclear Information System (INIS)

Leonhardt, T.; Moore, N.; Hamister, M.

2001-01-01

The development of a high-density, spherical rhenium powder (SReP) possessing excellent flow characteristics has enabled the use of advanced processing techniques for the manufacture of rhenium components. The techniques that were investigated were vacuum plasma spraying (VPS), direct-hot isostatic pressing (D-HIP), and various other traditional powder metallurgy processing methods of forming rhenium powder into near-net shaped components. The principal disadvantages of standard rhenium metal powder (RMP) for advanced consolidation applications include: poor flow characteristics; high oxygen content; and low and varying packing densities. SReP will lower costs, reduce processing times, and improve yields when manufacturing powder metallurgy rhenium components. The results of the powder characterization of spherical rhenium powder and the consolidation of the SReP are further discussed. (author)

Internship Progress Summary: Fall 2016

Energy Technology Data Exchange (ETDEWEB)

Wiser, Ralph S. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Valencia, Matthew John [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2016-12-13

This fall I had the opportunity to work at Los Alamos National Laboratory for the Technology Applications engineering group. I assisted two main projects during my appointment, both related to the Lab’s mission statement: “To solve national security challenges through scientific excellence.” My first project, a thermal source transfer unit, involved skills such as mechanical design, heat transfer simulation, and design analysis. The goal was to create a container that could protect a heat source and regulate its temperature during transit. I generated several designs, performed heat transfer simulations, and chose a design for prototyping. The second project was a soil drying unit for use in post blast sample analysis. To ensure fast and accurate sample processing, agents in the field wanted a system that could process wet dirt and turn it into dry powder. We designed a system of commercially available parts, and we tested the systems to determine the best methods and processes.

Measurement of loose powder density

International Nuclear Information System (INIS)

Akhtar, S.; Ali, A.; Haider, A.; Farooque, M.

2011-01-01

Powder metallurgy is a conventional technique for making engineering articles from powders. Main objective is to produce final products with the highest possible uniform density, which depends on the initial loose powder characteristics. Producing, handling, characterizing and compacting materials in loose powder form are part of the manufacturing processes. Density of loose metallic or ceramic powder is an important parameter for die design. Loose powder density is required for calculating the exact mass of powder to fill the die cavity for producing intended green density of the powder compact. To fulfill this requirement of powder metallurgical processing, a loose powder density meter as per ASTM standards is designed and fabricated for measurement of density. The density of free flowing metallic powders can be determined using Hall flow meter funnel and density cup of 25 cm/sup 3/ volume. Density of metal powders like cobalt, manganese, spherical bronze and pure iron is measured and results are obtained with 99.9% accuracy. (author)

Relationship between subjective fall risk assessment and falls and fall-related fractures in frail elderly people

Directory of Open Access Journals (Sweden)

Shimada Hiroyuki

2011-08-01

Full Text Available Abstract Background Objective measurements can be used to identify people with risks of falls, but many frail elderly adults cannot complete physical performance tests. The study examined the relationship between a subjective risk rating of specific tasks (SRRST to screen for fall risks and falls and fall-related fractures in frail elderly people. Methods The SRRST was investigated in 5,062 individuals aged 65 years or older who were utilized day-care services. The SRRST comprised 7 dichotomous questions to screen for fall risks during movements and behaviours such as walking, transferring, and wandering. The history of falls and fall-related fractures during the previous year was reported by participants or determined from an interview with the participant's family and care staff. Results All SRRST items showed significant differences between the participants with and without falls and fall-related fractures. In multiple logistic regression analysis adjusted for age, sex, diseases, and behavioural variables, the SRRST score was independently associated with history of falls and fractures. Odds ratios for those in the high-risk SRRST group (≥ 5 points compared with the no risk SRRST group (0 point were 6.15 (p Conclusion These results suggest that subjective ratings by care staff can be utilized to determine the risks of falls and fall-related fractures in the frail elderly, however, these preliminary results require confirmation in further prospective research.

Patient centered fall risk awareness perspectives: clinical correlates and fall risk

Science.gov (United States)

Verghese, Joe

2016-01-01

Background While objective measures to assess risk of falls in older adults have been established; the value of patient self-reports in the context of falls is not known. Objectives To identify clinical correlates of patient centered fall risk awareness, and their validity for predicting falls. Design Prospective cohort study. Setting and Participants 316 non-demented and ambulatory community-dwelling older adults (mean age 78 years, 55% women). Measurements Fall risk awareness was assessed with a two-item questionnaire, which asked participants about overall likelihood and personal risk of falling over the next 12 months. Incident falls were recorded over study follow-up. Results Fifty-three participants (16.8%) responded positively to the first fall risk awareness question about being likely to have a fall in the next 12 months, and 100 (31.6%) reported being at personal risk of falling over the next 12 months. There was only fair correlation (kappa 0.370) between responses on the two questions. Prior falls and depressive symptoms were associated with positive responses on both fall risk awareness questions. Age and other established fall risk factors were not associated with responses on both fall risk awareness questions. The fall risk awareness questionnaire did not predict incident falls or injurious falls. Conclusion Fall risk awareness is low in older adults. While patient centered fall risk awareness is not predictive of falls, subjective risk perceptions should be considered when designing fall preventive strategies as they may influence participation and behaviors. PMID:27801936

Fundamentals of powder metallurgy

International Nuclear Information System (INIS)

Khan, I.H.; Qureshi, K.A.; Minhas, J.I.

1988-01-01

This book is being presented to introduce the fundamentals of technology of powder metallurgy. An attempt has been made to present an overall view of powder metallurgy technology in the first chapter, whereas chapter 2 to 8 deal with the production of metal powders. The basic commercial methods of powder production are briefly described with illustrations. Chapter 9 to 12 describes briefly metal powder characteristics and principles of testing, mixing, blending, conditioning, compaction and sintering. (orig./A.B.)

Fall-related activity avoidance in relation to a history of falls or near falls, fear of falling and disease severity in people with Parkinson's disease.

Science.gov (United States)

Kader, Manzur; Iwarsson, Susanne; Odin, Per; Nilsson, Maria H

2016-06-02

There is limited knowledge concerning fall-related activity avoidance in people with Parkinson's disease (PD); such knowledge would be of importance for the development of more efficient PD-care and rehabilitation. This study aimed to examine how fall-related activity avoidance relates to a history of self-reported falls/near falls and fear of falling (FOF) as well as to disease severity in people with PD. Data were collected from 251 (61 % men) participants with PD; their median (min-max) age and PD duration were 70 (45-93) and 8 (1-43) years, respectively. A self-administered postal survey preceded a home visit which included observations, clinical tests and interview-administered questionnaires. Fall-related activity avoidance was assessed using the modified Survey of Activities and Fear of Falling in the Elderly (mSAFFE) as well as by using a dichotomous (Yes/No) question. Further dichotomous questions concerned: the presence of FOF and the history (past 6 months) of falls or near falls, followed by stating the number of incidents. Disease severity was assessed according to the Hoehn and Yahr (HY) stages. In the total sample (n = 251), 41 % of the participants reported fall-related activity avoidance; the median mSAFFE score was 22. In relation to a history of fall, the proportions of participants (p fall-related activity avoidance were: non-fallers (30 %), single fallers (50 %) and recurrent fallers, i.e. ≥ 2 falls (57 %). Among those that reported near falls (but no falls), 51 % (26 out of 51) reported fall-related activity avoidance. Of those that reported FOF, 70 % reported fall-related activity avoidance. Fall-related activity avoidance ranged from 24 % in the early PD-stage (HY I) to 74 % in the most severe stages (HY IV-V). Results indicate that fall-related activity avoidance may be related to a history of self-reported falls/near falls, FOF and disease severity in people with PD. Importantly, fall-related activity avoidance is

Mitigating fall risk: A community fall reduction program.

Science.gov (United States)

Reinoso, Humberto; McCaffrey, Ruth G; Taylor, David W M

One fourth of all American's over 65 years of age fall each year. Falls are a common and often devastating event that can pose a serious health risk for older adults. Healthcare providers are often unable to spend the time required to assist older adults with fall risk issues. Without a team approach to fall prevention the system remains focused on fragmented levels of health promotion and risk prevention. The specific aim of this project was to engage older adults from the community in a fall risk assessment program, using the Stopping Elderly Accidents, Deaths & Injuries (STEADI) program, and provide feedback on individual participants' risks that participants could share with their primary care physician. Older adults who attended the risk screening were taking medications that are known to increase falls. They mentioned that their health care providers do not screen for falls and appreciated a community based screening. Copyright © 2017 Elsevier Inc. All rights reserved.

Person-Centered Fall Risk Awareness Perspectives: Clinical Correlates and Fall Risk.

Science.gov (United States)

Verghese, Joe

2016-12-01

To identify clinical correlates of person-centered fall risk awareness and their validity for predicting falls. Prospective cohort study. Community. Ambulatory community-dwelling older adults without dementia (N = 316; mean age 78, 55% female). Fall risk awareness was assessed using a two-item questionnaire that asked participants about overall likelihood of someone in their age group having a fall and their own personal risk of falling over the next 12 months. Incident falls were recorded over study follow-up. Fifty-three participants (16.8%) responded positively to the first fall risk awareness question about being likely to have a fall in the next 12 months, and 100 (31.6%) reported being at personal risk of falling over the next 12 months. There was only fair correlation (κ = 0.370) between responses on the two questions. Prior falls and depressive symptoms were associated with positive responses on both fall risk awareness questions. Age and other established fall risk factors were not associated with responses on either fall risk awareness question. The fall risk awareness questionnaire did not predict incident falls or injurious falls. Fall risk awareness is low in older adults. Although person-centered fall risk awareness is not predictive of falls, subjective risk perceptions should be considered when designing fall preventive strategies because they may influence participation and behaviors. © 2016, Copyright the Author Journal compilation © 2016, The American Geriatrics Society.

Falls and Fear of Falling After Stroke: A Case-Control Study.

Science.gov (United States)

Goh, Hui-Ting; Nadarajah, Mohanasuntharaam; Hamzah, Norhamizan Binti; Varadan, Parimalaganthi; Tan, Maw Pin

2016-12-01

Falls are common after stroke, with potentially serious consequences. Few investigations have included age-matched control participants to directly compare fall characteristics between older adults with and without stroke. Further, fear of falling, a significant psychological consequence of falls, has only been examined to a limited degree as a risk factor for future falls in a stroke population. To compare the fall history between older adults with and without a previous stroke and to identify the determinants of falls and fear of falling in older stroke survivors. Case-control observational study. Primary teaching hospital. Seventy-five patients with stroke (mean age ± standard deviation, 66 ± 7 years) and 50 age-matched control participants with no previous stroke were tested. Fall history, fear of falling, and physical, cognitive, and psychological function were assessed. A χ 2 test was performed to compare characteristics between groups, and logistic regression was performed to determine the risk factors for falls and fear of falling. Fall events in the past 12 months, Fall Efficacy Scale-International, Berg Balance Scale, Functional Ambulation Category, Fatigue Severity Scale, Montreal Cognitive Assessment, and Patient Healthy Questionnaire-9 were measured for all participants. Fugl-Meyer Motor Assessment was used to quantify severity of stroke motor impairments. Twenty-three patients and 13 control participants reported at least one fall in the past 12 months (P = .58). Nine participants with stroke had recurrent falls (≥2 falls) compared with none of the control participants (P falling than did nonstroke control participants (P falls in the nonstroke group, whereas falls in the stroke group were not significantly associated with any measured outcomes. Fear of falling in the stroke group was associated with functional ambulation level and balance. Functional ambulation level alone explained 22% of variance in fear of falling in the stroke group

Low pressure powder injection moulding of stainless steel powders

Energy Technology Data Exchange (ETDEWEB)

Zampieron, J.V.; Soares, J.P.; Mathias, F.; Rossi, J.L. [Powder Processing Center CCP, Inst. de Pesquisas Energeticas e Nucleares, Sao Paulo, SP (Brazil); Filho, F.A. [IPEN, Inst. de Pesquisas Energeticas e Nucleares, Cidade Univ., Sao Paulo, SP (Brazil)

2001-07-01

Low-pressure powder injection moulding was used to obtain AISI 316L stainless steel parts. A rheological study was undertaken using gas-atomised powders and binders. The binders used were based on carnauba wax, paraffin, low density polyethylene and microcrystalline wax. The metal powders were characterised in terms of morphology, particle size distribution and specific surface area. These results were correlated to the rheological behaviour. The mixture was injected in the shape of square bar specimens to evaluate the performance of the injection process in the green state, and after sintering. The parameters such as injection pressure, viscosity and temperature were analysed for process optimisation. The binders were thermally removed in low vacuum with the assistance of alumina powders. Debinding and sintering were performed in a single step. This procedure shortened considerably the debinding and sintering time. (orig.)

Fear of falling as seen in the Multidisciplinary falls consultation.

Science.gov (United States)

Gaxatte, C; Nguyen, T; Chourabi, F; Salleron, J; Pardessus, V; Delabrière, I; Thévenon, A; Puisieux, F

2011-06-01

Fear of falling may be as debilitating as the fall itself, leading to a restriction in activities and even a loss of autonomy. The main objective was to evaluate the prevalence of the fear of falling among elderly fallers. The secondary objectives were to determine the factors associated with the fear of falling and evaluate the impact of this fear on the activity "getting out of the house". Prospective study conducted between 1995 and 2006 in which fallers and patients at high risk for falling were seen at baseline by the multidisciplinary falls consultation team (including a geriatrician, a neurologist and a physical medicine and rehabilitation physician) and then, again 6 month later, by the same geriatrician. The fear of falling was evaluated with a yes/no question: "are you afraid of falling?". Out of 635 patients with a mean age of 80.6 years, 502 patients (78%) expressed a fear of falling. Patients with fear of falling were not older than those who did not report this fear, but the former were mostly women (Pfear of falling were not going out alone as much as the fearless group (31% vs 53%, Pfearful group admitted to avoiding going out because they were afraid of falling. The strong prevalence of the fear of falling observed in this population and its consequences in terms of restricted activities justifies systematically screening for it in fallers or patients at risk for falling. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

Falling and fall risk in adult patients with severe haemophilia.

Science.gov (United States)

Rehm, Hanna; Schmolders, Jan; Koob, Sebastian; Bornemann, Rahel; Goldmann, Georg; Oldenburg, Johannes; Pennekamp, Peter; Strauss, Andreas C

2017-05-10

The objective of this study was to define fall rates and to identify possible fall risk factors in adult patients with severe haemophilia. 147 patients with severe haemophilia A and B were evaluated using a standardized test battery consisting of demographic, medical and clinical variables and fall evaluation. 41 (27.9 %) patients reported a fall in the past 12 months, 22 (53.7 %) of them more than once. Young age, subjective gait insecurity and a higher number of artificial joints seem to be risk factors for falling. Falls seem to be a common phenomenon in patients with severe haemophilia. Fall risk screening and fall prevention should be implemented into daily practice.

Foundations of powder metallurgy

International Nuclear Information System (INIS)

Libenson, G.A.

1987-01-01

Consideration is being given to physicochemical foundations and technology of metal powders, moulding and sintering of bars, made of them or their mixtures with nonmetal powders. Data on he design of basic equipment used in the processes of powder metallurgy and its servicing are presented. General requirements of safety engineering when fabricating metal powders and products of them are mentioned

Neutronic study of the two french heavy water reactors; Etude neutronique des deux piles francaises a eau lourde

Energy Technology Data Exchange (ETDEWEB)

Horowitz, J [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1955-07-01

The two french reactors - the reactor of Chatillon, named Zoe, and the reactor of Saclay - P2 - were the object of detailed neutronic studies which the main ideas are exposed in this report. These studies were mostly done by the Department of the Reactor Studies (D.E.P.). We have thus studied the distribution of neutronic fluxes; the factors influencing reactivity; the link between reactivity and divergence with the formula of Nordheim; the mean time life of neutrons; neutron spectra s of P2; the xenon effect; or the effect of the different adjustments of the plates and controls bar. (M.B.) [French] Les deux reacteurs francais - la pile de Chatillon, appelee ZOE, et la pile de Saclay, designee dans la suite par P2 - ont fait l'objet d'etudes neutroniques detaillees dont les principales sont exposees dans ce rapport. Ces etudes ont ete pour la plupart effectuees dans le cadre du Departement des Etudes de Piles (D.E.P.). Nous avons ainsi entre autre etudie la distribution du flux neutronique; les facteurs influencants la reactivite; le lien entre reactivite et divergence par la formule de Nordheim; le temps de vie moyen des neutrons; les spectres de neutrons de P2; l'effet xenon; ou encore l'effet des differents reglages des plaques et barres de controles. (M.B.)

Use of whey powder and skim milk powder for the production of fermented cream

Directory of Open Access Journals (Sweden)

Ceren AKAL

2016-01-01

Full Text Available Abstract This study is about the production of fermented cream samples having 18% fat by addition of starter cultures. In order to partialy increase non-fat solid content of fermented cream samples, skim milk powder and demineralized whey powder in two different rates (50% and 70% were used. Samples were analyzed for changes in their biochemical and physicochemical properties (total solid, ash, fat, titratable acidity, pH value, total nitrogen, viscosity, tyrosine, acid number, peroxide and diacetyl values during 29-day of storage period. Samples tested consisted of 7 different groups; control group (without adding any powder, skim milk powder, 50% demineralized whey powder and 70% demineralized whey powder samples were in two different addition rate (2% and 4%. Also samples were analyzed for sensory properties. According to the results obtained, the addition of milk powder products affected titratable acidity and tyrosine values of fermented cream samples. Although powder addition and/or storage period didn’t cause significant variations in total solid, ash, fat, pH value, viscosity, acid number, peroxide, tyrosine and diacetyl values; sensory properties of fermented cream samples were influenced by both powder addition and storage period. Fermented cream containing 2% skim milk powder gets the top score of sensory evaluation among the samples.

Etude de l'impact de la variation de la température sur les activités ...

African Journals Online (AJOL)

Etude de l'impact de la variation de la température sur les activités microbiennes : application à une population de Listeria monocytogenes CIP 7831, Listeria monocytogenes Scott A CIP 103575 et Escherichia coli ATCC 25922.

The falls and the fear of falling among elderly institutionalized

Directory of Open Access Journals (Sweden)

Patrícia Almeida

2013-06-01

Full Text Available In the present study it is intended to characterize the history of falls and to evaluate the fear to fall in aged institutionalized. The sample is composed for 113 institutionalized aged people, 32 men and 81 women with a average 82,96 ± 7,03 age of years. The data had been collected by means of a questionnaire and statistical analyzed (descriptive statistics, parametric tests - Test T and Anova - Test U-Mann Whitney, and Test of Kruskal-Wallis – and the Test of Tukey. The results point in the direction of that the women present a bigger number of falls (24.8% and greater fear to fall (Med=55. The falls had occurred in its majority in the context of the room of the institutions. It was verified that people who had at least a fall experience present greater fear to fall comparatively (Med=55 with that they had not the same had no incident of fall in period of time (Med=77. Our results come to strengthen the hypothesis of the changeable sex to be able to be considered a factor of fall risk. Aged that they present a history of falls seems to be more vulnerable to develop the fear to fall.

21 CFR 520.1696a - Buffered penicillin powder, penicillin powder with buffered aqueous diluent.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Buffered penicillin powder, penicillin powder with... FORM NEW ANIMAL DRUGS § 520.1696a Buffered penicillin powder, penicillin powder with buffered aqueous diluent. (a) Specifications. When reconstituted, each milliliter contains penicillin G procaine equivalent...

Biaxially textured articles formed by powder metallurgy

Science.gov (United States)

Goyal, Amit; Williams, Robert K.; Kroeger, Donald M.

2003-08-05

A biaxially textured alloy article having a magnetism less than pure Ni includes a rolled and annealed compacted and sintered powder-metallurgy preform article, the preform article having been formed from a powder mixture selected from the group of ternary mixtures consisting of: Ni powder, Cu powder, and Al powder, Ni powder, Cr powder, and Al powder; Ni powder, W powder and Al powder; Ni powder, V powder, and Al powder; Ni powder, Mo powder, and Al powder; the article having a fine and homogeneous grain structure; and having a dominant cube oriented {100} orientation texture; and further having a Curie temperature less than that of pure Ni.

Falls efficacy, postural balance, and risk for falls in older adults with falls-related emergency department visits: prospective cohort study.

Science.gov (United States)

Pua, Yong-Hao; Ong, Peck-Hoon; Clark, Ross Allan; Matcher, David B; Lim, Edwin Choon-Wyn

2017-12-21

Risk for falls in older adults has been associated with falls efficacy (self-perceived confidence in performing daily physical activities) and postural balance, but available evidence is limited and mixed. We examined the interaction between falls efficacy and postural balance and its association with future falls. We also investigated the association between falls efficacy and gait decline. Falls efficacy, measured by the Modified Falls Efficacy Scale (MFES), and standing postural balance, measured using computerized posturography on a balance board, were obtained from 247 older adults with a falls-related emergency department visit. Six-month prospective fall rate and habitual gait speed at 6 months post baseline assessment were also measured. In multivariable proportional odds analyses adjusted for potential confounders, falls efficacy modified the association between postural balance and fall risk (interaction P = 0.014): increasing falls efficacy accentuated the increased fall risk related to poor postural balance. Low baseline falls efficacy was strongly predictive of worse gait speed (0.11 m/s [0.06 to 0.16] slower gait speed per IQR decrease in MFES; P falls efficacy but poor postural balance were at greater risk for falls than those with low falls efficacy; however, low baseline falls efficacy was strongly associated with worse gait function at follow-up. Further research into these subgroups of older adults is warranted. ClinicalTrials.gov identifier: NCT01713543 .

Theoretical study, and construction, of a spherical electrostatic beta spectrometer; Etude theorique et realisation d'un spectrometre beta electrostatique spherique

Energy Technology Data Exchange (ETDEWEB)

Moret, R [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

1964-03-15

After a literature survey showing the importance of an electrostatic spectrometer with spherical electrodes for studying disintegration processes, the theoretical characteristics of such an apparatus are derived (determination of the trajectory equations calculation of the transmission and of the resolving power the case of a point source and of an extended source). The apparatus built as a result of these calculations is described. The electrostatic field distribution outside the electrodes is derived. As well as giving electron spectra ({beta} disintegration and conversion electrons) the apparatus make s it possible to study e-{gamma}, e-{beta}, e-e-{gamma} and e-e-{beta} coincidences. In the last part are given experimental characteristics and the results of the first measurements made on conversion electron spectra ({sup 161}Tb, {sup 151}Pm, {sup 155}Eu) and on coincidences ({sup 170}Tm) using this spectrometer. (author) [French] Apres une etude bibliographique montrant l'interet que presente un spectrometre electrostatique a electrodes spheriques pour l'etude des schemas de desintegration, l'auteur etablit les caracteristiques theoriques d'un tel appareil (determination de l'equation des trajectoires calcul de la transmission et du pouvoir de resolution cas d'une source ponctuelle et d'une source etendue). On decrit l'appareil realise d'apres ces calculs. On etablit la repartition du champ electrostatique a l'exterieur des electrodes. Outre le trace des spectres d'electrons (desintegration {beta} et electrons de conversion), l'appareil permet l'etude de coincidences e-{gamma}, e-{beta}, e-e-{gamma} and e-e-{beta}. Dans la derniere partie, sont donnees les caracteristiques experimentales et les premieres etudes de spectres d'electrons de conversion ({sup 161}Tb, {sup 151}Pm, {sup 155}Eu) et de coincidences ({sup 170}Tm) faites a l'aide de ce spectrometre. (auteur)

A piece of paper falling faster than free fall

International Nuclear Information System (INIS)

Vera, F; Rivera, R

2011-01-01

We report a simple experiment that clearly demonstrates a common error in the explanation of the classic experiment where a small piece of paper is put over a book and the system is let fall. This classic demonstration is used in introductory physics courses to show that after eliminating the friction force with the air, the piece of paper falls with acceleration g. To test if the paper falls behind the book in a nearly free fall motion or if it is dragged by the book, we designed a version of this experiment that includes a ball and a piece of paper over a book that is forced to fall using elastic cords. We recorded a video of our experiment using a high-speed video camera at 300 frames per second that shows that the book and the paper fall faster than the ball, which falls well behind the book with an acceleration approximately equal to g. Our experiment shows that the piece of paper is dragged behind the book and therefore the paper and book demonstration should not be used to show that all objects fall with acceleration g independently of their mass.

A piece of paper falling faster than free fall

Energy Technology Data Exchange (ETDEWEB)

Vera, F; Rivera, R, E-mail: fvera@ucv.cl [Instituto de Fisica, Pontificia Universidad Catolica de ValparaIso, Av. Universidad 330, Curauma, ValparaIso (Chile)

2011-09-15

We report a simple experiment that clearly demonstrates a common error in the explanation of the classic experiment where a small piece of paper is put over a book and the system is let fall. This classic demonstration is used in introductory physics courses to show that after eliminating the friction force with the air, the piece of paper falls with acceleration g. To test if the paper falls behind the book in a nearly free fall motion or if it is dragged by the book, we designed a version of this experiment that includes a ball and a piece of paper over a book that is forced to fall using elastic cords. We recorded a video of our experiment using a high-speed video camera at 300 frames per second that shows that the book and the paper fall faster than the ball, which falls well behind the book with an acceleration approximately equal to g. Our experiment shows that the piece of paper is dragged behind the book and therefore the paper and book demonstration should not be used to show that all objects fall with acceleration g independently of their mass.

An analysis of un-dissolved powders of instant powdered soup by using ultrasonographic image

Science.gov (United States)

Kawaai, Yukinori; Kato, Kunihito; Yamamoto, Kazuhiko; Kasamatsu, Chinatsu

2008-11-01

Nowadays, there are many instant powdered soups around us. When we make instant powdered soup, sometimes we cannot dissolve powders perfectly. Food manufacturers want to improve this problem in order to make better products. Therefore, they have to measure the state and volume of un-dissolved powders. Earlier methods for analyzing removed the un-dissolved powders from the container, the state of the un-dissolved power was changed. Our research using ultrasonographic image can measure the state of un-dissolved powders with no change by taking cross sections of the soup. We then make 3D soup model from these cross sections of soup. Therefore we can observe the inside of soup that we do not have ever seen. We construct accurate 3D model. We can visualize the state and volume of un-dissolved powders with analyzing the 3D soup models.

Biaxially textured articles formed by powder metallurgy

Science.gov (United States)

Goyal, Amit; Williams, Robert K.; Kroeger, Donald M.

2003-07-29

A biaxially textured alloy article having a magnetism less than pure Ni includes a rolled and annealed compacted and sintered powder-metallurgy preform article, the preform article having been formed from a powder mixture selected from the group of mixtures consisting of: at least 60 at % Ni powder and at least one of Cr powder, W powder, V powder, Mo powder, Cu powder, Al powder, Ce powder, YSZ powder, Y powder, Mg powder, and RE powder; the article having a fine and homogeneous grain structure; and having a dominant cube oriented {100} orientation texture; and further having a Curie temperature less than that of pure Ni.

Characterization of ceramic powder compacts

International Nuclear Information System (INIS)

Yanai, K.; Ishimoto, S.; Kubo, T.; Ito, K.; Ishikawa, T.; Hayashi, H.

1995-01-01

UO 2 and Al 2 O 3 powder packing structures in cylindrical powder compacts are observed by scanning electron microscopy using polished cross sections of compacts fixed by low viscosity epoxy resin. Hard aggregates which are not destroyed during powder compaction are observed in some of the UO 2 powder compacts. A technique to measure local density in powder compacts is developed based on counting characteristic X-ray intensity by energy dispersive X-ray analysis (EDX). The local density of the corner portion of the powder compact fabricated by double-acting dry press is higher than that of the inner portion. ((orig.))

Operation whey powder

International Nuclear Information System (INIS)

Brunner, E.

1987-01-01

The odyssey of the contaminated whey powder finally has come to an end, and the 5000 tonnes of whey now are designated for decontamination by means of an ion exchange technique. The article throws light upon the political and economic reasons that sent the whey powder off on a chaotic journey. It is worth mentioning in this context that the natural radioactivity of inorganic fertilizers is much higher than that of the whey powder in question. (HP) [de

Densification behavior of aluminum alloy powder mixed with zirconia powder inclusion under cold compaction

International Nuclear Information System (INIS)

Ryu, Hyun Seok; Lee, Sung Chul; Kim, Ki Tae

2002-01-01

Densification behavior of composite powders was investigated during cold compaction. Experimental data were obtained for aluminum alloy powder mixed with zirconia powder inclusion under triaxial compression. The cap model with constraint factors was implemented into a finite element program(ABAQUS) to simulate compaction responses of composite powders during cold compaction. Finite element results were compared with experimental data for densification behavior of composite powders under cold isostatic pressing and die compaction. The agreements between experimental data and finite element calculations from the cap model with constraint factors were good

Nuclear fuel powder transfer device

International Nuclear Information System (INIS)

Komono, Akira

1998-01-01

A pair of parallel rails are laid between a receiving portion to a molding portion of a nuclear fuel powder transfer device. The rails are disposed to the upper portion of a plurality of parallel support columns at the same height. A powder container is disposed while being tilted in the inside of the vessel main body of a transfer device, and rotational shafts equipped with wheels are secured to right and left external walls. A nuclear powder to be mixed, together with additives, is supplied to the powder container of the transfer device. The transfer device engaged with the rails on the receiving side is transferred toward the molding portion. The wheels are rotated along the rails, and the rotational shafts, the vessel main body and the powder container are rotated. The nuclear powder in the tilted powder container disposed is rotated right and left and up and down by the rotation, and the powder is mixed satisfactory when it reaches the molding portion. (I.N.)

Optimal fall indicators for slip induced falls on a cross-slope.

Science.gov (United States)

Domone, Sarah; Lawrence, Daniel; Heller, Ben; Hendra, Tim; Mawson, Sue; Wheat, Jonathan

2016-08-01

Slip-induced falls are among the most common cause of major occupational injuries in the UK as well as being a major public health concern in the elderly population. This study aimed to determine the optimal fall indicators for fall detection models which could be used to reduce the detrimental consequences of falls. A total of 264 kinematic variables covering three-dimensional full body model translation and rotational measures were analysed during normal walking, successful recovery from slips and falls on a cross-slope. Large effect sizes were found for three kinematic variables which were able to distinguish falls from normal walking and successful recovery. Further work should consider other types of daily living activities as results show that the optimal kinematic fall indicators can vary considerably between movement types. Practitioner Summary: Fall detection models are used to minimise the adverse consequences of slip-induced falls, a major public health concern. Optimal fall indicators were derived from a comprehensive set of kinematic variables for slips on a cross-slope. Results suggest robust detection of falls is possible on a cross-slope but may be more difficult than level walking.

Falling chains

OpenAIRE

Wong, Chun Wa; Yasui, Kosuke

2005-01-01

The one-dimensional fall of a folded chain with one end suspended from a rigid support and a chain falling from a resting heap on a table is studied. Because their Lagrangians contain no explicit time dependence, the falling chains are conservative systems. Their equations of motion are shown to contain a term that enforces energy conservation when masses are transferred between subchains. We show that Cayley's 1857 energy nonconserving solution for a chain falling from a resting heap is inco...

Preparation of tris(8-hydroxyquinolinato)aluminum thin films by sputtering deposition using powder and pressed powder targets

Science.gov (United States)

Kawasaki, Hiroharu; Ohshima, Tamiko; Yagyu, Yoshihito; Ihara, Takeshi; Tanaka, Rei; Suda, Yoshiaki

2017-06-01

Tris(8-hydroxyquinolinato)aluminum (Alq3) thin films, for use in organic electroluminescence displays, were prepared by a sputtering deposition method using powder and pressed powder targets. Experimental results suggest that Alq3 thin films can be prepared using powder and pressed powder targets, although the films were amorphous. The surface color of the target after deposition became dark brown, and the Fourier transform infrared spectroscopy spectrum changed when using a pressed powder target. The deposition rate of the film using a powder target was higher than that using a pressed powder target. That may be because the electron and ion densities of the plasma generated using the powder target are higher than those when using pressed powder targets under the same deposition conditions. The properties of a thin film prepared using a powder target were almost the same as those of a film prepared using a pressed powder target.

Point-of-care ultrasonography adoption in Canada: using diffusion theory and the Evaluation Tool for Ultrasound skills Development and Education (ETUDE).

Science.gov (United States)

Woo, Michael Y; Frank, Jason R; Lee, A Curtis

2014-09-01

Point-of-care ultrasonography (PoCUS) first appeared in the 1980s in North America, but the extent of the diffusion of its adoption is unknown. We characterized early PoCUS adoption by emergency physicians in Canada and its barriers to use using Rogers' diffusion of innovations theory. We developed a questionnaire based on a pilot study and literature review to assess past, current, and potential use of PoCUS and potential barriers to adoption. A Dillman technique for electronic surveys was used for dissemination. Using Rogers' diffusion of innovations theory, we developed and validated the Evaluation Tool for Ultrasound skills Development and Education (ETUDE). ETUDE scores allowed categorization of respondents into innovators, early adopters, majority, and nonadopters. Descriptive statistics, correlations, and χ² statistics were used to analyze the data. The 296 respondents (36.4% of 814 surveyed) had a median age of 40 and were 72.5% male. Adoption scores using ETUDE revealed nonadopters (18.8%), majority (28.7%), early adopters (34.5%), and innovators (18.0%). Respondents endorsed "always" using PoCUS currently and in the future for focused assessment with sonography in trauma (FAST) (current 41.8%/future 88.4%), first trimester pregnancy (current 23.3%/future 73.7%), suspected abdominal aortic aneurysm (current 32.7%/future 92.6%), basic cardiac indications (current 30.7%/future 87.5%), and central venous catheterization (current 17.0%/future 80.3%). Several barriers to PoCUS were identified for part-time emergency physicians and those working in inner-city/urban/suburban settings. This is the first study to determine the state of adoption and barriers to the introduction of PoCUS in Canadian emergency medicine practice. The novel validated ETUDE instrument should be used to evaluate the uptake of PoCUS over time.

Influence of Ultrafine 2CaO·SiO₂ Powder on Hydration Properties of Reactive Powder Concrete.

Science.gov (United States)

Sun, Hongfang; Li, Zishanshan; Memon, Shazim Ali; Zhang, Qiwu; Wang, Yaocheng; Liu, Bing; Xu, Weiting; Xing, Feng

2015-09-17

In this research, we assessed the influence of an ultrafine 2CaO·SiO₂ powder on the hydration properties of a reactive powder concrete system. The ultrafine powder was manufactured through chemical combustion method. The morphology of ultrafine powder and the development of hydration products in the cement paste prepared with ultrafine powder were investigated by scanning electron microscopy (SEM), mineralogical composition were determined by X-ray diffraction, while the heat release characteristics up to the age of 3 days were investigated by calorimetry. Moreover, the properties of cementitious system in fresh and hardened state (setting time, drying shrinkage, and compressive strength) with 5% ordinary Portland cement replaced by ultrafine powder were evaluated. From SEM micrographs, the particle size of ultrafine powder was found to be up to several hundred nanometers. The hydration product started formulating at the age of 3 days due to slow reacting nature of belitic 2CaO·SiO₂. The initial and final setting times were prolonged and no significant difference in drying shrinkage was observed when 5% ordinary Portland cement was replaced by ultrafine powder. Moreover, in comparison to control reactive powder concrete, the reactive powder concrete containing ultrafine powder showed improvement in compressive strength at and above 7 days of testing. Based on above, it can be concluded that the manufactured ultrafine 2CaO·SiO₂ powder has the potential to improve the performance of a reactive powder cementitious system.

Application of laser in powder metallurgy

International Nuclear Information System (INIS)

Tolochko, N.K.

1995-01-01

Modern status of works in the field of laser application in powder metallurgy (powders preparation, sintering, coatings formation, powder materials processing) is considered. The attention is paid to the new promising direction in powder products shape-formation technology - laser layer-by-layer selective powders sintering and bulk sintering of packaged layered profiles produced by laser cutting of powder-based sheet blanks. 67 refs

Increasing fall risk awareness using wearables: A fall risk awareness protocol.

Science.gov (United States)

Danielsen, Asbjørn; Olofsen, Hans; Bremdal, Bernt Arild

2016-10-01

Each year about a third of elderly aged 65 or older experience a fall. Many of these falls may have been avoided if fall risk assessment and prevention tools where available in a daily living situation. We identify what kind of information is relevant for doing fall risk assessment and prevention using wearable sensors in a daily living environment by investigating current research, distinguishing between prospective and context-aware fall risk assessment and prevention. Based on our findings, we propose a fall risk awareness protocol as a fall prevention tool integrating both wearables and ambient sensing technology into a single platform. Copyright © 2016. Published by Elsevier Inc.

Relationship between subjective fall risk assessment and falls and fall-related fractures in frail elderly people

OpenAIRE

Shimada, Hiroyuki; Suzukawa, Megumi; Ishizaki, Tatsuro; Kobayashi, Kumiko; Kim, Hunkyung; Suzuki, Takao

2011-01-01

Abstract Background Objective measurements can be used to identify people with risks of falls, but many frail elderly adults cannot complete physical performance tests. The study examined the relationship between a subjective risk rating of specific tasks (SRRST) to screen for fall risks and falls and fall-related fractures in frail elderly people. Methods The SRRST was investigated in 5,062 individuals aged 65 years or older who were utilized day-care services. The SRRST comprised 7 dichotom...

Fall Protection Introduction, #33462

Energy Technology Data Exchange (ETDEWEB)

Chochoms, Michael [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2016-06-23

The proper use of fall prevention and fall protection controls can reduce the risk of deaths and injuries caused by falls. This course, Fall Protection Introduction (#33462), is designed as an introduction to various types of recognized fall prevention and fall protection systems at Los Alamos National Laboratory (LANL), including guardrail systems, safety net systems, fall restraint systems, and fall arrest systems. Special emphasis is given to the components, inspection, care, and storage of personal fall arrest systems (PFASs). This course also presents controls for falling object hazards and emergency planning considerations for persons who have fallen.

The clinical practice guideline for falls and fall risk

OpenAIRE

Vance, Jacqueline

2011-01-01

Falling is a significant cause of injury and death in frail older adults. Residents in long-term care (LTC) facilities fall for a variety of reasons and are more likely to endure injuries after a fall than those in the community The American Medical Directors Association (AMDA) Clinical Practice Guideline is written to give LTC staff an understanding of risk factors for falls and provide guidance for a systematic approach to patient assessment and selection of appropriate interventions. It is...

Prediction of falls and/or near falls in people with mild Parkinson's disease.

Directory of Open Access Journals (Sweden)

Beata Lindholm

Full Text Available To determine factors associated with future falls and/or near falls in people with mild PD.The study included 141 participants with PD. Mean (SD age and PD-duration were 68 (9.7 and 4 years (3.9, respectively. Their median (q1-q3 UPDRS III score was 13 (8-18. Those >80 years of age, requiring support in standing or unable to understand instructions were excluded. Self-administered questionnaires targeted freezing of gait, turning hesitations, walking difficulties in daily life, fatigue, fear of falling, independence in activities of daily living, dyskinesia, demographics, falls/near falls history, balance problems while dual tasking and pain. Clinical assessments addressed functional balance performance, retropulsion, comfortable gait speed, motor symptoms and cognition. All falls and near falls were subsequently registered in a diary during a six-month period. Risk factors for prospective falls and/or near falls were determined using logistic regression.Sixty-three participants (45% experienced ≥ 1 fall and/or near fall. Three factors were independent predictors of falls and/or near falls: fear of falling (OR = 1.032, p<0.001 history of near falls (OR = 3.475, p = 0.009 and retropulsion (OR = 2.813, p = 0.035. The strongest contributing factor was fear of falling, followed by a history of near falls and retropulsion.Fear of falling seems to be an important issue to address already in mild PD as well as asking about prior near falls.

The formation of scientists and technicians at the 'Centre d'Etudes Nucleaires' at Saclay

International Nuclear Information System (INIS)

Debiesse, J.

1958-01-01

The considerable needs in research workers and scientists which are asked by the nuclear energy obliged the Commissariat a l'Energie atomique to deal with a particular effort to increase the quantitative and qualitative formation of scientists. Most various ways have been used. 1- A National Institute of Nuclear Sciences and Nuclear Techniques was created, by a joint decree of the Prime Minister and the Minister for National Education (june 18, 1957). This Institute of Higher Teaching (250 students) indulges in the following matters: atomic engineering, quantum mechanics, theory and technic of particle accelerators, special metallurgy, radiobiology, thermic and mechanics of fluids. 2- An associated centre of the 'Conservatoire National des Arts et Metiers' was created (200 students) for technical assistants, drawers, etc. 3- In contribution with both electronic industry and Ministry of Work, the Centre d'Etudes Nucleaires contributes to an accelerated formation of technical assistants into Professional Centres. Conclusion: Training of scientists and research workers is one of the most important activities of the Centre d'Etudes Nucleaires de Saclay. Without losing its technical efficiency, it has supplied and varied means adapted to the various purposes that we shall reach. (author) [fr

Unexplained Falls Are Frequent in Patients with Fall-Related Injury Admitted to Orthopaedic Wards: The UFO Study (Unexplained Falls in Older Patients).

Science.gov (United States)

Chiara, Mussi; Gianluigi, Galizia; Pasquale, Abete; Alessandro, Morrione; Alice, Maraviglia; Gabriele, Noro; Paolo, Cavagnaro; Loredana, Ghirelli; Giovanni, Tava; Franco, Rengo; Giulio, Masotti; Gianfranco, Salvioli; Niccolò, Marchionni; Andrea, Ungar

2013-01-01

To evaluate the incidence of unexplained falls in elderly patients affected by fall-related fractures admitted to orthopaedic wards, we recruited 246 consecutive patients older than 65 (mean age 82 ± 7 years, range 65-101). Falls were defined "accidental" (fall explained by a definite accidental cause), "medical" (fall caused directly by a specific medical disease), "dementia-related" (fall in patients affected by moderate-severe dementia), and "unexplained" (nonaccidental falls, not related to a clear medical or drug-induced cause or with no apparent cause). According to the anamnestic features of the event, older patients had a lower tendency to remember the fall. Patients with accidental fall remember more often the event. Unexplained falls were frequent in both groups of age. Accidental falls were more frequent in younger patients, while dementia-related falls were more common in the older ones. Patients with unexplained falls showed a higher number of depressive symptoms. In a multivariate analysis a higher GDS and syncopal spells were independent predictors of unexplained falls. In conclusion, more than one third of all falls in patients hospitalized in orthopaedic wards were unexplained, particularly in patients with depressive symptoms and syncopal spells. The identification of fall causes must be evaluated in older patients with a fall-related injury.

Container for nuclear fuel powders

International Nuclear Information System (INIS)

Etheredge, B.F.; Larson, R.I.

1982-01-01

A critically safe container is disclosed for the storage and rapid discharge of enriched nuclear fuel material in powder form is disclosed. The container has a hollow, slab-shaped container body that has one critically safe dimension. A powder inlet is provided on one side wall of the body adjacent to a corner thereof and a powder discharge port is provided at another corner of the body approximately diagonal the powder inlet. Gas plenum for moving the powder during discharge are located along the side walls of the container adjacent the discharge port

Preparation of superconductor precursor powders

Science.gov (United States)

Bhattacharya, Raghunath

1998-01-01

A process for the preparation of a precursor metallic powder composition for use in the subsequent formation of a superconductor. The process comprises the steps of providing an electrodeposition bath comprising an electrolyte medium and a cathode substrate electrode, and providing to the bath one or more soluble salts of one or more respective metals which are capable of exhibiting superconductor properties upon subsequent appropriate treatment. The bath is continually energized to cause the metallic and/or reduced particles formed at the electrode to drop as a powder from the electrode into the bath, and this powder, which is a precursor powder for superconductor production, is recovered from the bath for subsequent treatment. The process permits direct inclusion of all metals in the preparation of the precursor powder, and yields an amorphous product mixed on an atomic scale to thereby impart inherent high reactivity. Superconductors which can be formed from the precursor powder include pellet and powder-in-tube products.

Falls and fear of falling predict future falls and related injuries in ambulatory individuals with spinal cord injury: a longitudinal observational study.

Science.gov (United States)

Jørgensen, Vivien; Butler Forslund, Emelie; Opheim, Arve; Franzén, Erika; Wahman, Kerstin; Hultling, Claes; Seiger, Åke; Ståhle, Agneta; Stanghelle, Johan K; Roaldsen, Kirsti S

2017-04-01

What is the 1-year incidence of falls and injurious falls in a representative cohort of community-dwelling ambulatory individuals with chronic spinal cord injury? What are the predictors of recurrent falls (more than two/year) and injurious falls in this population? One-year longitudinal observational multi-centre study. A representative sample of 68 (of 73 included) community-dwelling ambulatory individuals with traumatic SCI attending regular follow-up programs at rehabilitation centres. Primary outcome measures were incidence and predictors of recurrent falls (more than two/year) and injurious falls reported every 2 weeks for 1year. A total of 48% of participants reported recurrent falls. Of the 272 reported falls, 41% were injurious. Serious injuries were experienced by 4% of participants, all of whom were women. Multivariate logistic regression analysis showed that recurrent falls in the previous year (OR=111, 95% CI=8.6 to 1425), fear of falling (OR=6.1, 95% CI=1.43 to 26) and longer time taken to walk 10m (OR=1.3, 95% CI=1.0 to 1.7) were predictors of recurrent falls. Fear of falling (OR=4.3, 95% CI=1.3 to 14) and recurrent falls in the previous year (OR=4.2, 95% CI=1.2 to 14) were predictors of injurious falls. Ambulatory individuals have a high risk of falling and of fall-related injuries. Fall history, fear of falling and walking speed could predict recurrent falls and injurious falls. Further studies with larger samples are needed to validate these findings. [Jørgensen V, Butler Forslund E, Opheim A, Franzén E, Wahman K, Hultling C, Seiger Å, Ståhle A, Stanghelle JK, Roaldsen KS (2017) Falls and fear of falling predict future falls and related injuries in ambulatory individuals with spinal cord injury: a longitudinal observational study. Journal of Physiotherapy 63: 108-113]. Copyright © 2017 Australian Physiotherapy Association. Published by Elsevier B.V. All rights reserved.

Unexplained Falls Are Frequent in Patients with Fall-Related Injury Admitted to Orthopaedic Wards: The UFO Study (Unexplained Falls in Older Patients

Directory of Open Access Journals (Sweden)

Mussi Chiara

2013-01-01

Full Text Available To evaluate the incidence of unexplained falls in elderly patients affected by fall-related fractures admitted to orthopaedic wards, we recruited 246 consecutive patients older than 65 (mean age 82±7 years, range 65–101. Falls were defined “accidental” (fall explained by a definite accidental cause, “medical” (fall caused directly by a specific medical disease, “dementia-related” (fall in patients affected by moderate-severe dementia, and “unexplained” (nonaccidental falls, not related to a clear medical or drug-induced cause or with no apparent cause. According to the anamnestic features of the event, older patients had a lower tendency to remember the fall. Patients with accidental fall remember more often the event. Unexplained falls were frequent in both groups of age. Accidental falls were more frequent in younger patients, while dementia-related falls were more common in the older ones. Patients with unexplained falls showed a higher number of depressive symptoms. In a multivariate analysis a higher GDS and syncopal spells were independent predictors of unexplained falls. In conclusion, more than one third of all falls in patients hospitalized in orthopaedic wards were unexplained, particularly in patients with depressive symptoms and syncopal spells. The identification of fall causes must be evaluated in older patients with a fall-related injury.

Bio-metric study of pig karyotype; Etude biometrique du caryotype du porc

Energy Technology Data Exchange (ETDEWEB)

Haag, J; Lacourly, N; Nizza, P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1969-07-01

This study has a twofold purpose, the former is to determine the swine karyotype as accurately as possible, the latter is to try and develop a method of automatic classification and to show its possibilities and limits. (authors) [French] Cette etude a un double objet: d'une part, de definir de la facon aussi precise que possible le caryotype du porc et d'autre part, de tenter une methode de classification automatique et d'en montrer les possibilites ainsi que les limites. (auteurs)

Associated Factors for Falls, Recurrent Falls, and Injurious Falls in Aged Men Living in Taiwan Veterans Homes

Directory of Open Access Journals (Sweden)

Yan-Chiou Ku

2013-06-01

Conclusion: This study demonstrated that the advanced age, depression status, stroke, gouty arthritis, and cataract are independent variables for predicting falls; depression is the only clinical factor capable of predicting the recurrent falls. These variables were potential targets for effective prevention of falls.

Influence of Ultrafine 2CaO·SiO2 Powder on Hydration Properties of Reactive Powder Concrete

Directory of Open Access Journals (Sweden)

Hongfang Sun

2015-09-01

Full Text Available In this research, we assessed the influence of an ultrafine 2CaO·SiO2 powder on the hydration properties of a reactive powder concrete system. The ultrafine powder was manufactured through chemical combustion method. The morphology of ultrafine powder and the development of hydration products in the cement paste prepared with ultrafine powder were investigated by scanning electron microscopy (SEM, mineralogical composition were determined by X-ray diffraction, while the heat release characteristics up to the age of 3 days were investigated by calorimetry. Moreover, the properties of cementitious system in fresh and hardened state (setting time, drying shrinkage, and compressive strength with 5% ordinary Portland cement replaced by ultrafine powder were evaluated. From SEM micrographs, the particle size of ultrafine powder was found to be up to several hundred nanometers. The hydration product started formulating at the age of 3 days due to slow reacting nature of belitic 2CaO·SiO2. The initial and final setting times were prolonged and no significant difference in drying shrinkage was observed when 5% ordinary Portland cement was replaced by ultrafine powder. Moreover, in comparison to control reactive powder concrete, the reactive powder concrete containing ultrafine powder showed improvement in compressive strength at and above 7 days of testing. Based on above, it can be concluded that the manufactured ultrafine 2CaO·SiO2 powder has the potential to improve the performance of a reactive powder cementitious system.

Magnetically responsive enzyme powders

Energy Technology Data Exchange (ETDEWEB)

Pospiskova, Kristyna, E-mail: kristyna.pospiskova@upol.cz [Regional Centre of Advanced Technologies and Materials, Palacky University, Slechtitelu 11, 783 71 Olomouc (Czech Republic); Safarik, Ivo, E-mail: ivosaf@yahoo.com [Regional Centre of Advanced Technologies and Materials, Palacky University, Slechtitelu 11, 783 71 Olomouc (Czech Republic); Department of Nanobiotechnology, Institute of Nanobiology and Structural Biology of GCRC, Na Sadkach 7, 370 05 Ceske Budejovice (Czech Republic)

2015-04-15

Powdered enzymes were transformed into their insoluble magnetic derivatives retaining their catalytic activity. Enzyme powders (e.g., trypsin and lipase) were suspended in various liquid media not allowing their solubilization (e.g., saturated ammonium sulfate and highly concentrated polyethylene glycol solutions, ethanol, methanol, 2-propanol) and subsequently cross-linked with glutaraldehyde. Magnetic modification was successfully performed at low temperature in a freezer (−20 °C) using magnetic iron oxides nano- and microparticles prepared by microwave-assisted synthesis from ferrous sulfate. Magnetized cross-linked enzyme powders were stable at least for two months in water suspension without leakage of fixed magnetic particles. Operational stability of magnetically responsive enzymes during eight repeated reaction cycles was generally without loss of enzyme activity. Separation of magnetically modified cross-linked powdered enzymes from reaction mixtures was significantly simplified due to their magnetic properties. - Highlights: • Cross-linked enzyme powders were prepared in various liquid media. • Insoluble enzymes were magnetized using iron oxides particles. • Magnetic iron oxides particles were prepared by microwave-assisted synthesis. • Magnetic modification was performed under low (freezing) temperature. • Cross-linked powdered trypsin and lipase can be used repeatedly for reaction.

Sintered aluminium powders

International Nuclear Information System (INIS)

Stepanova, M.G.; Matveev, B.I.

1974-01-01

The mechanical and physical properties of aluminium powder alloys and the various methods employed to produce them are considered. Data are given on the hardening of the alloys SAP and SPAK-4, as well as the powder-alloy system Al-Cr-Zr. (L.M.)

Falls and fear of falling predict future falls and related injuries in ambulatory individuals with spinal cord injury: a longitudinal observational study

Directory of Open Access Journals (Sweden)

Vivien Jørgensen

2017-04-01

Conclusion: Ambulatory individuals have a high risk of falling and of fall-related injuries. Fall history, fear of falling and walking speed could predict recurrent falls and injurious falls. Further studies with larger samples are needed to validate these findings. [Jørgensen V, Butler Forslund E, Opheim A, Franzén E, Wahman K, Hultling C, Seiger Å, Ståhle A, Stanghelle JK, Roaldsen KS (2017 Falls and fear of falling predict future falls and related injuries in ambulatory individuals with spinal cord injury: a longitudinal observational study. Journal of Physiotherapy 63: 108–113

Powder diffraction

Energy Technology Data Exchange (ETDEWEB)

Hart, M.

1995-12-31

the importance of x-ray powder diffraction as an analytical tool for phase identification of materials was first pointed out by Debye and Scherrer in Germany and, quite independently, by Hull in the US. Three distinct periods of evolution lead to ubiquitous application in many fields of science and technology. In the first period, until the mid-1940`s, applications were and developed covering broad categories of materials including inorganic materials, minerals, ceramics, metals, alloys, organic materials and polymers. During this formative period, the concept of quantitative phase analysis was demonstrated. In the second period there followed the blossoming of technology and commercial instruments became widely used. The history is well summarized by Parrish and by Langford and Loueer. By 1980 there were probably 10,000 powder diffractometers in routine use, making it the most widely used of all x-ray crystallographic instruments. In the third, present, period data bases became firmly established and sophisticated pattern fitting and recognition software made many aspects of powder diffraction analysis routine. High resolution, tunable powder diffractometers were developed at sources of synchrotron radiation. The tunability of the spectrum made it possible to exploit all the subtleties of x-ray spectroscopy in diffraction experiments.

Powder diffraction

International Nuclear Information System (INIS)

Hart, M.

1995-01-01

The importance of x-ray powder diffraction as an analytical tool for phase identification of materials was first pointed out by Debye and Scherrer in Germany and, quite independently, by Hull in the US. Three distinct periods of evolution lead to ubiquitous application in many fields of science and technology. In the first period, until the mid-1940's, applications were and developed covering broad categories of materials including inorganic materials, minerals, ceramics, metals, alloys, organic materials and polymers. During this formative period, the concept of quantitative phase analysis was demonstrated. In the second period there followed the blossoming of technology and commercial instruments became widely used. The history is well summarized by Parrish and by Langford and Loueer. By 1980 there were probably 10,000 powder diffractometers in routine use, making it the most widely used of all x-ray crystallographic instruments. In the third, present, period data bases became firmly established and sophisticated pattern fitting and recognition software made many aspects of powder diffraction analysis routine. High resolution, tunable powder diffractometers were developed at sources of synchrotron radiation. The tunability of the spectrum made it possible to exploit all the subtleties of x-ray spectroscopy in diffraction experiments

Impact of Fall Prevention on Nurses and Care of Fall Risk Patients.

Science.gov (United States)

King, Barbara; Pecanac, Kristen; Krupp, Anna; Liebzeit, Daniel; Mahoney, Jane

2018-03-19

Falls are common events for hospitalized older adults, resulting in negative outcomes both for patients and hospitals. The Center for Medicare and Medicaid (CMS) has placed pressure on hospital administrators by identifying falls as a "never event", resulting in a zero falls goal for many hospitals. Staff nurses are responsible for providing direct care to patients and for meeting the hospital no falls goal. Little is known about the impact of "zero falls" on nurses, patients and the organization. A qualitative study, using Grounded Dimensional Analysis (GDA) was conducted to explore nurses' experiences with fall prevention in hospital settings and the impact of those experiences on how nurses provide care to fall risk patients. Twenty-seven registered nurses and certified nursing assistants participated in in-depth interviews. Open, axial and selective coding was used to analyze data. A conceptual model which illustrates the impact of intense messaging from nursing administration to prevent patient falls on nurses, actions nurses take to address the message and the consequences to nurses, older adult patients and to the organization was developed. Intense messaging from hospital administration to achieve zero falls resulted in nurses developing a fear of falls, protecting self and unit, and restricting fall risk patients as a way to stop messages and meet the hospital goal. Results of this study identify unintended consequences of fall prevention message on nurses and older adult patients. Further research is needed understand how nurse care for fall risk patients.

Method to blend separator powders

Science.gov (United States)

Guidotti, Ronald A.; Andazola, Arthur H.; Reinhardt, Frederick W.

2007-12-04

A method for making a blended powder mixture, whereby two or more powders are mixed in a container with a liquid selected from nitrogen or short-chain alcohols, where at least one of the powders has an angle of repose greater than approximately 50 degrees. The method is useful in preparing blended powders of Li halides and MgO for use in the preparation of thermal battery separators.

Effect of a Multidisciplinary Fall Risk Assessment on Falls Among Neurology Inpatients

Science.gov (United States)

Hunderfund, Andrea N. Leep; Sweeney, Cynthia M.; Mandrekar, Jayawant N.; Johnson, LeAnn M.; Britton, Jeffrey W.

2011-01-01

OBJECTIVE: To evaluate whether the addition of a physician assessment of patient fall risk at admission would reduce inpatient falls on a tertiary hospital neurology inpatient unit. PATIENTS AND METHODS: A physician fall risk assessment was added to the existing risk assessment process (clinical nurse evaluation and Hendrich II Fall Risk Model score with specific fall prevention measures for patients at risk). An order to select either “Patient is” or “Patient is not at high risk of falls by physician assessment” was added to the physician electronic admission order set. Nurses and physicians were instructed to reach consensus when assessments differed. Full implementation occurred in second-quarter 2008. Preimplementation (January 1, 2006, to March 31, 2008) and postimplementation (April 1, 2008, to December 31, 2009) rates of falls were compared on the neurology inpatient unit and on 6 other medical units that did not receive intervention. RESULTS: The rate of falls during the 7 quarters after full implementation was significantly lower than that during the 9 preceding quarters (4.12 vs 5.69 falls per 1000 patient-days; P=.04), whereas the rate of falls on other medical units did not significantly change (2.99 vs 3.33 falls per 1000 patient-days; P=.24, Poisson test). The consensus risk assessment at admission correctly identified patients at risk for falls (14/325 at-risk patients fell vs 0/147 low-risk patients; P=.01, χ2 test), but the Hendrich II Fall Risk Model score, nurse, and physician assessments individually did not. CONCLUSION: A multidisciplinary approach to fall risk assessment is feasible, correctly identifies patients at risk, and was associated with a reduction in inpatient falls. PMID:21193651

Falls and falls efficacy: the role of sustained attention in older adults

LENUS (Irish Health Repository)

O'Halloran, Aisling M

2011-12-19

Abstract Background Previous evidence indicates that older people allocate more of their attentional resources toward their gait and that the attention-related changes that occur during aging increase the risk of falls. The aim of this study was to investigate whether performance and variability in sustained attention is associated with falls and falls efficacy in older adults. Methods 458 community-dwelling adults aged ≥ 60 years underwent a comprehensive geriatric assessment. Mean and variability of reaction time (RT), commission errors and omission errors were recorded during a fixed version of the Sustained Attention to Response Task (SART). RT variability was decomposed using the Fast Fourier Transform (FFT) procedure, to help characterise variability associated with the arousal and vigilance aspects of sustained attention. The number of self-reported falls in the previous twelve months, and falls efficacy (Modified Falls Efficacy Scale) were also recorded. Results Significant increases in the mean and variability of reaction time on the SART were significantly associated with both falls (p < 0.01) and reduced falls efficacy (p < 0.05) in older adults. An increase in omission errors was also associated with falls (p < 0.01) and reduced falls efficacy (p < 0.05). Upon controlling for age and gender affects, logistic regression modelling revealed that increasing variability associated with the vigilance (top-down) aspect of sustained attention was a retrospective predictor of falling (p < 0.01, OR = 1.14, 95% CI: 1.03 - 1.26) in the previous year and was weakly correlated with reduced falls efficacy in non-fallers (p = 0.07). Conclusions Greater variability in sustained attention is strongly correlated with retrospective falls and to a lesser degree with reduced falls efficacy. This cognitive measure may provide a novel and valuable biomarker for falls in older adults, potentially allowing for early detection and the implementation of preventative intervention

Fall Risk, Supports and Services, and Falls Following a Nursing Home Discharge.

Science.gov (United States)

Noureldin, Marwa; Hass, Zachary; Abrahamson, Kathleen; Arling, Greg

2017-09-04

Falls are a major source of morbidity and mortality among older adults; however, little is known regarding fall occurrence during a nursing home (NH) to community transition. This study sought to examine whether the presence of supports and services impacts the relationship between fall-related risk factors and fall occurrence post NH discharge. Participants in the Minnesota Return to Community Initiative who were assisted in achieving a community discharge (N = 1459) comprised the study sample. The main outcome was fall occurrence within 30 days of discharge. Factor analyses were used to estimate latent models from variables of interest. A structural equation model (SEM) was estimated to determine the relationship between the emerging latent variables and falls. Fifteen percent of participants fell within 30 days of NH discharge. Factor analysis of fall-related risk factors produced three latent variables: fall concerns/history; activities of daily living impairments; and use of high-risk medications. A supports/services latent variable also emerged that included caregiver support frequency, medication management assistance, durable medical equipment use, discharge location, and receipt of home health or skilled nursing services. In the SEM model, high-risk medications use and fall concerns/history had direct positive effects on falling. Receiving supports/services did not affect falling directly; however, it reduced the effect of high-risk medication use on falling (p risk of falling post NH discharge. © The Author 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.

Molybdenum plasma spray powder, process for producing said powder, and coating made therefrom

International Nuclear Information System (INIS)

Lafferty, W.D.; Cheney, R.F.; Pierce, R.H.

1979-01-01

Plasma spray powders of molybdenum particles containing 0.5 to 15 weight percent oxygen and obtained by reacting molybdenum particles with oxygen or oxides in a plasma, form plasma spray coatings exhibiting hardness comparable to flame sprayed coatings formed from molybdenum wire and plasma coatings of molybdenum powders. Such oxygen rich molybdenum powders may be used to form wear resistant coatings, such as for piston rings. (author)

SAF line powder operations

International Nuclear Information System (INIS)

Frederickson, J.R.; Horgos, R.M.

1983-10-01

An automated nuclear fuel fabrication line is being designed for installation in the Fuels and Materials Examination Facility (FMEF) near Richland, Washington. The fabrication line will consist of seven major process systems: Receiving and Powder Preparation; Powder Conditioning; Pressing and Boat Loading; Debinding, Sintering, and Property Adjustment; Boat Transport; Pellet Inspection and Finishing; and Pin Operations. Fuel powder processing through pellet pressing will be discussed in this paper

Two layer powder pressing

International Nuclear Information System (INIS)

Schreiner, H.

1979-01-01

First, significance and advantages of sintered materials consisting of two layers are pointed out. By means of the two layer powder pressing technique metal powders are formed resulting in compacts with high accuracy of shape and mass. Attributes of basic powders, different filling methods and pressing techniques are discussed. The described technique is supposed to find further applications in the field of two layer compacts in the near future

Critical Design Review of a Powder HIPed Shield Concept. Final Report for the contract EFDA/01-601

International Nuclear Information System (INIS)

Lind, Anders

2002-05-01

The Shield of the ITER Primary Wall Module Option A consists of a 316L Stainless Steel block with front and back side radially cooled through water headers. In order to avoid structural welds located in high irradiation fields or highly mechanically loaded, powder HIPing was proposed by the EU Home Team as a possible fabrication method. This choice was motivated by the good results obtained through an extensive R and D programme performed within Associations and Industries. However, this fabrication technique has some implications on the design of the component, which shall be considered from the very beginning to achieve good performance and low cost. A critical review was therefore needed to optimise the concept before the fabrication of a Shield prototype. The contractor, based on its own experience on powder HIP technology and on the support from appropriate industry, did check the fabrication feasibility of the proposed Shield concept. The concept was judged to be feasible to a combined powder/solid HIPing route. Some adjustments of the design were proposed. The price for producing one shield block in a series of 400 items was estimated to fall into the range 150,000 - 175,000 Euro/pc

Falls and Fall-Related Injuries among Community-Dwelling Adults in the United States.

Directory of Open Access Journals (Sweden)

Santosh K Verma

Full Text Available Falls are the leading cause of unintentional injuries in the U.S.; however, national estimates for all community-dwelling adults are lacking. This study estimated the national incidence of falls and fall-related injuries among community-dwelling U.S. adults by age and gender and the trends in fall-related injuries across the adult life span.Nationally representative data from the National Health Interview Survey (NHIS 2008 Balance and Dizziness supplement was used to develop national estimates of falls, and pooled data from the NHIS was used to calculate estimates of fall-related injuries in the U.S. and related trends from 2004-2013. Costs of unintentional fall-related injuries were extracted from the CDC's Web-based Injury Statistics Query and Reporting System.Twelve percent of community-dwelling U.S. adults reported falling in the previous year for a total estimate of 80 million falls at a rate of 37.2 falls per 100 person-years. On average, 9.9 million fall-related injuries occurred each year with a rate of 4.38 fall-related injuries per 100 person-years. In the previous three months, 2.0% of older adults (65+, 1.1% of middle-aged adults (45-64 and 0.7% of young adults (18-44 reported a fall-related injury. Of all fall-related injuries among community-dwelling adults, 32.3% occurred among older adults, 35.3% among middle-aged adults and 32.3% among younger adults. The age-adjusted rate of fall-related injuries increased 4% per year among older women (95% CI 1%-7% from 2004 to 2013. Among U.S. adults, the total lifetime cost of annual unintentional fall-related injuries that resulted in a fatality, hospitalization or treatment in an emergency department was 111 billion U.S. dollars in 2010.Falls and fall-related injuries represent a significant health and safety problem for adults of all ages. The findings suggest that adult fall prevention efforts should consider the entire adult lifespan to ensure a greater public health benefit.

Etude cinétique de la dégradation de l'Endosufane en solution ...

African Journals Online (AJOL)

Etude cinétique de la dégradation de l'Endosufane en solution. S Traore, K Mamadou, A Dembele, V Yao, Y Bekro, P Mazellier, B Legube, P Houenou. Abstract. Les pesticides sont fréquemment utilisés en Côte d'Ivoire. Leur détection dans les eaux de forage témoigne de leur mauvais usage et d'un grave problème ...

The Association Between Fall Frequency, Injury Risk, and Characteristics of Falls in Older Residents of Long-Term Care: Do Recurrent Fallers Fall More Safely?

Science.gov (United States)

van Schooten, Kimberley S; Yang, Yijian; Feldman, Fabio; Leung, Ming; McKay, Heather; Sims-Gould, Joanie; Robinovitch, Stephen N

2018-05-09

Although a fall is a necessary prerequisite to a fall-related injury, previous studies suggest that frequent fallers are at lower injury risk for a given fall. We tested the hypotheses that differences in protective responses or the circumstances of falls underlie differences in injury risk with fall frequency. We analyzed video footage of 897 falls experienced by 220 long-term care residents (mean age 82 ± 9 years) to identify the cause of imbalance, activity leading to falling, direction of fall initiation, balance recovery and fall protective responses, and occurrence of impact to the head or hip. We further obtained injury information from the facilities' fall registration. We used generalized estimating equation models to examine the association between quartiles of fall frequency, injury risk, and fall characteristics. Residents with the highest fall frequency group (Q4; ≥5.6 falls/year) were less likely to sustain an injury per fall. They were less likely to fall during walking and more likely to fall during stand-to-sit transfers. Residents in the lowest fall frequency group (Q1; falls/year) were more likely to fall during walking, and walking was associated with an increased risk for injury. When compared to less frequent fallers, more frequent fallers had a lower risk for injury per fall. This appeared to be explained by differences in the circumstances of falls, and not by protective responses. Injury prevention strategies in long-term care should target both frequent and infrequent fallers, as the latter are more mobile and apt to sustain injury.

Falls in multiple sclerosis.

Science.gov (United States)

Matsuda, Patricia N; Shumway-Cook, Anne; Bamer, Alyssa M; Johnson, Shana L; Amtmann, Dagmar; Kraft, George H

2011-07-01

To examine incidence, associated factors, and health care provider (HCP) response to falls in persons with multiple sclerosis (MS). Cross-sectional retrospective design. Community setting. Four hundred seventy-four persons with MS. Mailed survey questionnaire examined incidence, risk factors, and HCP response to falls in persons with MS who were dwelling in the community. Univariate and multiple ordinal regression analysis identified variables associated with single and multiple falls. Falls, causes and perceived reasons for falls, and HCP response. A total of 265 participants (58.2%) reported one or more falls in the previous 6 months, and 58.5% of falls were medically injurious. Trips/slips while walking accounted for 48% of falls. Factors associated with falls included use of a cane or walker (odds ratio [OR] 2.62; 95% confidence interval [CI] 1.66-4.14), income falls; recommended strategies included safety strategies (53.2%), use of gait assistive devices (42.1%), exercise/balance training (22.2%), and home modifications (16.6%). Factors associated with falls in persons with MS are similar to those in other populations with neurologic diseases. Despite the high incidence of falls, fewer than 50% of people with MS receive information about prevention of falls from an HCP. Copyright © 2011 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

The analysis of powder diffraction data

International Nuclear Information System (INIS)

David, W.I.F.; Harrison, W.T.A.

1986-01-01

The paper reviews neutron powder diffraction data analysis, with emphasis on the structural aspects of powder diffraction and the future possibilities afforded by the latest generation of very high resolution neutron and x-ray powder diffractometers. Traditional x-ray powder diffraction techniques are outlined. Structural studies by powder diffraction are discussed with respect to the Rietveld method, and a case study in the Rietveld refinement method and developments of the Rietveld method are described. Finally studies using high resolution powder diffraction at the Spallation Neutron Source, ISIS at the Rutherford Appleton Laboratory are summarized. (U.K.)

The use radioactive tracers in the study of solid transport in water streams; Emploi de traceurs radioactifs pour l'etude du transport solide dans les cours d'eau

Energy Technology Data Exchange (ETDEWEB)

Courtois, G [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires; Jaffry, P; Heuzel, M [Laboratoire National d' Hydraulique de Chatou, 78 (France)

1960-07-01

The Laboratoire National d'Hydraulique which has been studying, during the last few years in conjunction with the Centre d'Etudes Nucleaires at Saclay, the development of apparatus and of methods of investigation of sediment transport by radioactive tracer techniques, is at the moment trying to perfect a genuinely quantitative method of investigation. Two experiments have recently been carried out in rivers, the first designed to investigate the transport of pebbles in the river Rhone, the other to investigate the movement of sands in the Niger. This second experiment has been supported by parallel experiments carried out on a reduced scale model of the Niger built at the laboratories of Chatou: in this experiment are used the radiation from {sup 56}Mn and {sup 24}Na obtained by direct activation of the crushed apricot store which represents, in the scale model, the natural sediment on the bed of the Niger. The combined efforts of the laboratories of Chatou and of the Centre d'Etudes Nucleaires at Saclay are at the moment directed to the application of radioactive tracers to studies on the scale models with the double aim: a) of having a single investigational method for the actual experiment and for the model making it possible to control the accuracy of the model in the preliminary stage of calibrating this model; b) of making the most of the possibilities of observation and of direct measurement offered by the scale models for studying the possibility of improving the tracer method, in particular with respect to the collecting of quantitative data. (author) [French] La Laboratoire National d'Hydraulique qui, depuis quelques annees a developpe, en collaboration avec le Centre d'Etudes Nucleaires de Saclay, les appareillages et les techniques d'etudes des mouvements de sediments par la methode des traceurs radioactifs, s'efforce actuellement de mettre au point un moyen d'investigation veritablement quantitatif. Deux experiences ont ete effectuees recemment en

Exploring Older Adult ED Fall Patients' Understanding of Their Fall: A Qualitative Study.

Science.gov (United States)

Shankar, Kalpana N; Taylor, Devon; Rizzo, Caroline T; Liu, Shan W

2017-12-01

We sought to understand older patients' perspectives about their fall, fall risk factors, and attitude toward emergency department (ED) fall-prevention interventions. We conducted semistructured interviews between July 2015 and January 2016 of community-dwelling, nondemented patients in the ED, who presented with a fall to an urban, teaching hospital. Interviews were halted once we achieve thematic saturation with the data coded and categorized into themes. Of the 63 patients interviewed, patients blamed falls on the environment, accidents, a medical condition, or themselves. Three major themes were generated: (1) patients blamed falls on a multitude of things but never acknowledged a possible multifactorial rationale, (2) patients have variable level of concerns regarding their current fall and future fall risk, and (3) patients demonstrated a range of receptiveness to ED interventions aimed at preventing falls but provided little input as to what those interventions should be. Many older patients who fall do not understand their fall risk. However, based on the responses provided, older adults tend to be more receptive to intervention and more concerned about their future fall risk, making the ED an appropriate setting for intervention.

Roller compaction of moist pharmaceutical powders.

Science.gov (United States)

Wu, C-Y; Hung, W-L; Miguélez-Morán, A M; Gururajan, B; Seville, J P K

2010-05-31

The compression behaviour of powders during roller compaction is dominated by a number of factors, such as process conditions (roll speed, roll gap, feeding mechanisms and feeding speed) and powder properties (particle size, shape, moisture content). The moisture content affects the powder properties, such as the flowability and cohesion, but it is not clear how the moisture content will influence the powder compression behaviour during roller compaction. In this study, the effect of moisture contents on roller compaction behaviour of microcrystalline cellulose (MCC, Avicel PH102) was investigated experimentally. MCC samples of different moisture contents were prepared by mixing as-received MCC powder with different amount of water that was sprayed onto the powder bed being agitated in a rotary mixer. The flowability of these samples were evaluated in terms of the poured angle of repose and flow functions. The moist powders were then compacted using the instrumented roller compactor developed at the University of Birmingham. The flow and compression behaviour during roller compaction and the properties of produced ribbons were examined. It has been found that, as the moisture content increases, the flowability of moist MCC powders decreases and the powder becomes more cohesive. As a consequence of non-uniform flow of powder into the compaction zone induced by the friction between powder and side cheek plates, all produced ribbons have a higher density in the middle and lower densities at the edges. For the ribbons made of powders with high moisture contents, different hydration states across the ribbon width were also identified from SEM images. Moreover, it was interesting to find that these ribbons were split into two halves. This is attributed to the reduction in the mechanical strength of moist powder compacts with high moisture contents produced at high compression pressures. Copyright (c) 2010 Elsevier B.V. All rights reserved.

Medication use and fall-risk assessment for falls in an acute care hospital.

Science.gov (United States)

Chiu, Ming-Huang; Lee, Hsin-Dai; Hwang, Hei-Fen; Wang, Shih-Chieh; Lin, Mau-Roung

2015-07-01

A nested case-control study was carried out to examine relationships of a fall-risk score and the use of single medications and polypharmacy with falls among hospitalized patients aged 50 years and older in Taiwan. There were 83 patients who experienced a fall during hospitalization in an acute-care hospital. Matched by age and sex, five control patients for each case were randomly selected from all other inpatients who had not experienced any fall at the time of the index fall. Patients who took tricyclic antidepressants, diuretics, and narcotics were 3.36-, 1.83- and 2.09-fold, respectively, more likely to experience a fall than their counterparts. Conversely, patients who took beta-blockers were 0.34-fold more likely than those who did not take them to experience a fall. Patients taking ≥6 medications were 3.08-fold more likely than those taking fewer medications to experience a fall, whereas those with anxiety were 4.72-fold more likely to experience a fall than those without. A high fall-risk score was not significantly associated with the occurrence of falls. Among older hospitalized patients, tricyclic antidepressants, diuretics, narcotics, and polypharmacy should be mindfully prescribed and reviewed on a regular basis. A fall-risk scale developed from community-dwelling older people might not accurately predict falls in hospitalized patients. Further research to validate the negative effect of beta-blocker use on falls is required. © 2014 Japan Geriatrics Society.

Black powder in gas pipelines

Energy Technology Data Exchange (ETDEWEB)

Sherik, Abdelmounam [Saudi Aramco, Dhahran (Saudi Arabia)

2009-07-01

Despite its common occurrence in the gas industry, black powder is a problem that is not well understood across the industry, in terms of its chemical and physical properties, source, formation, prevention or management of its impacts. In order to prevent or effectively manage the impacts of black powder, it is essential to have knowledge of its chemical and physical properties, formation mechanisms and sources. The present paper is divided into three parts. The first part of this paper is a synopsis of published literature. The second part reviews the recent laboratory and field work conducted at Saudi Aramco Research and Development Center to determine the compositions, properties, sources and formation mechanisms of black powder in gas transmission systems. Microhardness, nano-indentation, X-ray Diffraction (XRD), X-ray Fluorescence (XRF) and Scanning Electron Microscopy (SEM) techniques were used to analyze a large number of black powder samples collected from the field. Our findings showed that black powder is generated inside pipelines due to internal corrosion and that the composition of black powder is dependent on the composition of transported gas. The final part presents a summary and brief discussion of various black powder management methods. (author)

Falling and fall risk factors in adults with haemophilia: an exploratory study.

Science.gov (United States)

Sammels, M; Vandesande, J; Vlaeyen, E; Peerlinck, K; Milisen, K

2014-11-01

Falls are a particular risk in persons with haemophilia (PWH) because of damaged joints, high risk of bleeding, possible impact on the musculoskeletal system and functioning and costs associated with treatment for these fall-related injuries. In addition, fall risk increases with age and PWH are increasingly entering the over 65 age group. The aim of this study was to determine the occurrence of falls during the past year and to explore which fall risk factors are present in community-dwelling PWH. Dutch speaking community-dwelling adults were included from the age of 40 years with severe or moderate haemophilia A or B, independent in their mobility and registered at the University Hospitals Leuven. They were asked to come to the haemophilia centre; otherwise a telephone survey was conducted. Demographic and social variables, medical variables, fall evaluation and clinical variables were queried. From the 89 PWH, 74 (83.1%) participated in the study. Twenty-four (32.4%) fell in the past year, and 10 of them (41.7%) more than once with an average of four falls. Living conditions, physical activity, avoidance of winter sports due to fear of falling, orthopaedic status, urinary incontinence and mobility impairments are potential fall risk factors in adult PWH. This exploratory study indicates that PWH are attentive to falling since they are at higher risk for falls and because of the serious consequences it might have. Screening and fall prevention should be stimulated in the daily practice of haemophilia care. © 2014 John Wiley & Sons Ltd.

Thermal plasma spheroidization and spray deposition of barium titanate powder and characterization of the plasma sprayable powder

Energy Technology Data Exchange (ETDEWEB)

Pakseresht, A.H., E-mail: amirh_pak@yahoo.com [Department of Ceramics, Materials and Energy Research Center, P.O. Box 31787-316, Karaj (Iran, Islamic Republic of); Rahimipour, M.R. [Department of Ceramics, Materials and Energy Research Center, P.O. Box 31787-316, Karaj (Iran, Islamic Republic of); Vaezi, M.R. [Department of Nanotechnology and Advanced Materials, Materials and Energy Research Center, P.O. Box 31787-316, Karaj (Iran, Islamic Republic of); Salehi, M. [Department of Materials Engineering, Isfahan University of Technology, P.O. Box 84156-83111, Isfahan (Iran, Islamic Republic of)

2016-04-15

In this paper, atmospheric plasma spray method was used to produce dense plasma sprayable powder and thick barium titanate film. In this regard, the commercially feedstock powders were granulated and spheroidized by the organic binder and the thermal spray process, respectively. Scanning electron microscopy was used to investigate the microstructure of the produced powders and the final deposits. X-ray diffraction was also implemented to characterize phase of the sprayed powder. The results indicated that spheroidized powder had suitable flowability as well as high density. The micro-hardness of the film produced by the sprayed powders was higher than that of the film deposited by the irregular granules. Additionally, relative permittivity of the films was increased by decreasing the defects from 160 to 293 for film deposited using spheroidized powder. The reduction in the relative permittivity of deposits, in comparison with the bulk material, was due to the existence of common defects in the thermal spray process. - Highlights: • We prepare sprayable BaTiO{sub 3} powder with no or less inside voids for plasma spray application for first time. • The sprayable powder has good flow characteristics and high density. • Powder spheroidization via plasma spray improves the hardness and dielectric properties of the deposited film.

Thermal plasma spheroidization and spray deposition of barium titanate powder and characterization of the plasma sprayable powder

International Nuclear Information System (INIS)

Pakseresht, A.H.; Rahimipour, M.R.; Vaezi, M.R.; Salehi, M.

2016-01-01

In this paper, atmospheric plasma spray method was used to produce dense plasma sprayable powder and thick barium titanate film. In this regard, the commercially feedstock powders were granulated and spheroidized by the organic binder and the thermal spray process, respectively. Scanning electron microscopy was used to investigate the microstructure of the produced powders and the final deposits. X-ray diffraction was also implemented to characterize phase of the sprayed powder. The results indicated that spheroidized powder had suitable flowability as well as high density. The micro-hardness of the film produced by the sprayed powders was higher than that of the film deposited by the irregular granules. Additionally, relative permittivity of the films was increased by decreasing the defects from 160 to 293 for film deposited using spheroidized powder. The reduction in the relative permittivity of deposits, in comparison with the bulk material, was due to the existence of common defects in the thermal spray process. - Highlights: • We prepare sprayable BaTiO_3 powder with no or less inside voids for plasma spray application for first time. • The sprayable powder has good flow characteristics and high density. • Powder spheroidization via plasma spray improves the hardness and dielectric properties of the deposited film.

Which Fall Ascertainment Method Captures Most Falls in Pre-Frail and Frail Seniors?

Science.gov (United States)

Teister, Corina J; Chocano-Bedoya, Patricia O; Orav, Endel J; Dawson-Hughes, Bess; Meyer, Ursina; Meyer, Otto W; Freystaetter, Gregor; Gagesch, Michael; Rizzoli, Rene; Egli, Andreas; Theiler, Robert; Kanis, John A; Bischoff-Ferrari, Heike A

2018-06-15

There is no consensus on most reliable falls ascertainment method. Therefore, we investigated which method captures most falls among pre-frail and frail seniors from two randomized controlled trials conducted in Zurich, Switzerland, a 18-month trial (2009-2010) including 200 community-dwelling pre-frail seniors with a prior fall and a 12-month trial (2005-2008) including 173 frail seniors with acute hip fracture. Both included the same fall ascertainment methods: monthly active-asking, daily self-report diary, and a call-in hotline. We compared number of falls reported and estimated overall and positive percent agreement between methods. Pre-frail seniors reported 499 falls (rate = 2.5/year) and frail seniors reported 205 falls (rate = 1.4/year). Most falls were reported by active-asking: 81% of falls in pre-frail, and 78% in frail seniors. Among pre-frail seniors, diaries captured additional 19% falls, while hotline added none. Among frail seniors, hotline added 16% falls, while diaries added 6%. The positive percent agreement between active-asking and diary was 100% among pre-frail and 88% among frail seniors. While monthly active-asking captures most falls in both groups, this method alone missed 19% of falls in pre-frail and 22% in frail seniors. Thus, a combination of active-asking and diaries for pre-frail, and active-asking and the hotline for frail seniors is warranted.

Falls and Fall-Related Injuries among Community-Dwelling Adults in the United States

Science.gov (United States)

Verma, Santosh K.; Willetts, Joanna L.; Corns, Helen L.; Marucci-Wellman, Helen R.; Lombardi, David A.; Courtney, Theodore K.

2016-01-01

Introduction Falls are the leading cause of unintentional injuries in the U.S.; however, national estimates for all community-dwelling adults are lacking. This study estimated the national incidence of falls and fall-related injuries among community-dwelling U.S. adults by age and gender and the trends in fall-related injuries across the adult life span. Methods Nationally representative data from the National Health Interview Survey (NHIS) 2008 Balance and Dizziness supplement was used to develop national estimates of falls, and pooled data from the NHIS was used to calculate estimates of fall-related injuries in the U.S. and related trends from 2004–2013. Costs of unintentional fall-related injuries were extracted from the CDC’s Web-based Injury Statistics Query and Reporting System. Results Twelve percent of community-dwelling U.S. adults reported falling in the previous year for a total estimate of 80 million falls at a rate of 37.2 falls per 100 person-years. On average, 9.9 million fall-related injuries occurred each year with a rate of 4.38 fall-related injuries per 100 person-years. In the previous three months, 2.0% of older adults (65+), 1.1% of middle-aged adults (45–64) and 0.7% of young adults (18–44) reported a fall-related injury. Of all fall-related injuries among community-dwelling adults, 32.3% occurred among older adults, 35.3% among middle-aged adults and 32.3% among younger adults. The age-adjusted rate of fall-related injuries increased 4% per year among older women (95% CI 1%–7%) from 2004 to 2013. Among U.S. adults, the total lifetime cost of annual unintentional fall-related injuries that resulted in a fatality, hospitalization or treatment in an emergency department was 111 billion U.S. dollars in 2010. Conclusions Falls and fall-related injuries represent a significant health and safety problem for adults of all ages. The findings suggest that adult fall prevention efforts should consider the entire adult lifespan to ensure a

Near-falls in people with Parkinson's disease: Circumstances, contributing factors and association with falling.

Science.gov (United States)

Gazibara, Tatjana; Kisic Tepavcevic, Darija; Svetel, Marina; Tomic, Aleksandra; Stankovic, Iva; Kostic, Vladimir S; Pekmezovic, Tatjana

2017-10-01

To describe circumstances of near-falls among persons with Parkinson's disease (PD), assess factors associated with near-falling and assess whether near-falls in the first 6 months are associated with falling in the latter 6 months over one year of follow-up. In the period August 2011-December 2012, 120 consecutive persons with PD, who denied having fallen in the past 6 months, were recruited at Clinical center of Serbia in Belgrade. Occurrence of falling and near-falls was followed for one year. A total of 31 persons with PD (25.8%) experienced near-falls, but did not fall. Of 42 fallers, 32 (76.2%) experienced near-falls. Tripping was the most common cause of near-falls among fallers, whereas postural instability was the most common in non-fallers. Regardless of falling experience, the most common manner to avoid fall was holding onto furniture or wall. After adjustment for multiple motor and non-motor PD features, more severe freezing of gait was associated with occurrence of near-falls over one year of follow-up (odds ratio [OR]=1.08, 95% confidence interval [CI] 1.01-1.16; p=0.043). Adjusted regression analysis did not show associations between near-falling in the first 6 months and falling in the latter 6 months of follow-up. Near-falls commonly occur in persons with PD. More severe freezing of gait appears to predispose near-falling. Fall prevention programs focusing on balance maintenance when experiencing freezing of gait could potentially be useful in reduction of near-falls. Copyright © 2017 Elsevier B.V. All rights reserved.

Geriatric fall-related injuries.

African Journals Online (AJOL)

Conclusion: The majority of geriatric fall-related injuries were due to fall from the same level at home. Assessment of risk fac- tors for falls including home hazards is essential for prevention of geriatric fall-related injuries. Keywords: Accidental fall, geriatrics, injury, trauma registry. DOI: http://dx.doi.org/10.4314/ahs.v16i2.24.

Weighing fluidized powder

International Nuclear Information System (INIS)

Adomitis, J.T.; Larson, R.I.

1980-01-01

Fluidized powder is discharged from a fluidizing vessel into a container. Accurate metering is achieved by opening and closing the valve to discharge the powder in a series of short-duration periods until a predetermined weight is measured by a load cell. The duration of the discharge period may be increased in inverse proportion to the amount of powder in the vessel. Preferably the container is weighed between the discharge periods to prevent fluctuations resulting from dynamic effects. The gas discharged into the container causes the pressures in the vessel and container to equalize thereby decreasing the rate of discharge and increasing the accuracy of metering as the weight reaches the predetermined value. (author)

21 CFR 73.1647 - Copper powder.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Copper powder. 73.1647 Section 73.1647 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1647 Copper powder. (a) Identity. (1) The color additive copper powder is a very fine free-flowing metallic powder prepared from virgin electrolytic copper. It...

[Use of powder metallurgy for development of implants of Co-Cr-Mo alloy powder].

Science.gov (United States)

Dabrowski, J R

2001-04-01

This paper discusses the application of powder metallurgy for the development of porous implantation materials. Powders obtained from Co-Cr-Mo alloy with different carbon content by water spraying and grinding, have been investigated. Cold pressing and rotary re-pressing methods were used for compressing the powder. It was found that the sintered materials obtained from water spraying have the most advantageous properties.

Prevalence and cost of imaging in inpatient falls: the rising cost of falling

Directory of Open Access Journals (Sweden)

Fields J

2015-06-01

Full Text Available Jessica Fields,1 Tahani Alturkistani,2 Neal Kumar,3 Arjun Kanuri,3 Deeb N Salem,1 Samson Munn,2 Deborah Blazey-Martin1 1Department of Medicine, Tufts Medical Center, Boston, MA, USA; 2Department of Radiology, Tufts Medical Center, Boston, MA, USA; 3Tufts University School of Medicine, Boston, MA, USA Objective: To quantify the type, prevalence, and cost of imaging following inpatient falls, identify factors associated with post-fall imaging, and determine correlates of positive versus negative imaging. Design: Single-center retrospective cohort study of inpatient falls. Data were collected from the hospital's adverse event reporting system, DrQuality. Age, sex, date, time, and location of fall, clinical service, Morse Fall Scale/fall protocol, admitting diagnosis, and fall-related imaging studies were reviewed. Cost included professional and facilities fees for each study. Setting: Four hundred and fifteen bed urban academic hospital over 3 years (2008–2010. Patients: All adult inpatient falls during the study period were included. Falls experienced by patients aged <18 years, outpatient and emergency patients, visitors to the hospital, and staff were excluded. Measurements and main results: Five hundred and thirty inpatient falls occurred during the study period, average patient age 60.7 years (range 20–98. More than half of falls were men (55% and patients considered at risk of falls (56%. Falls were evenly distributed across morning (33%, evening (34%, and night (33% shifts. Of 530 falls, 178 (34% patients were imaged with 262 studies. Twenty percent of patients imaged had at least one positive imaging study attributed to the fall and 82% of studies were negative. Total cost of imaging was $160,897, 63% ($100,700 from head computed tomography (CT. Conclusion: Inpatient falls affect patients of both sexes, all ages, occur at any time of day and lead to expensive imaging, mainly from head CTs. Further study should be targeted toward

Reducing metal alloy powder costs for use in powder bed fusion additive manufacturing: Improving the economics for production

Science.gov (United States)

Medina, Fransisco

Titanium and its associated alloys have been used in industry for over 50 years and have become more popular in the recent decades. Titanium has been most successful in areas where the high strength to weight ratio provides an advantage over aluminum and steels. Other advantages of titanium include biocompatibility and corrosion resistance. Electron Beam Melting (EBM) is an additive manufacturing (AM) technology that has been successfully applied in the manufacturing of titanium components for the aerospace and medical industry with equivalent or better mechanical properties as parts fabricated via more traditional casting and machining methods. As the demand for titanium powder continues to increase, the price also increases. Titanium spheroidized powder from different vendors has a price range from 260/kg-450/kg, other spheroidized alloys such as Niobium can cost as high as $1,200/kg. Alternative titanium powders produced from methods such as the Titanium Hydride-Dehydride (HDH) process and the Armstrong Commercially Pure Titanium (CPTi) process can be fabricated at a fraction of the cost of powders fabricated via gas atomization. The alternative powders can be spheroidized and blended. Current sectors in additive manufacturing such as the medical industry are concerned that there will not be enough spherical powder for production and are seeking other powder options. It is believed the EBM technology can use a blend of spherical and angular powder to build fully dense parts with equal mechanical properties to those produced using traditional powders. Some of the challenges with angular and irregular powders are overcoming the poor flow characteristics and the attainment of the same or better packing densities as spherical powders. The goal of this research is to demonstrate the feasibility of utilizing alternative and lower cost powders in the EBM process. As a result, reducing the cost of the raw material to reduce the overall cost of the product produced with

Validation of the Saskatoon Falls Prevention Consortium's Falls Screening and Referral Algorithm

Science.gov (United States)

Lawson, Sara Nicole; Zaluski, Neal; Petrie, Amanda; Arnold, Cathy; Basran, Jenny

2013-01-01

ABSTRACT Purpose: To investigate the concurrent validity of the Saskatoon Falls Prevention Consortium's Falls Screening and Referral Algorithm (FSRA). Method: A total of 29 older adults (mean age 77.7 [SD 4.0] y) residing in an independent-living senior's complex who met inclusion criteria completed a demographic questionnaire and the components of the FSRA and Berg Balance Scale (BBS). The FSRA consists of the Elderly Fall Screening Test (EFST) and the Multi-factor Falls Questionnaire (MFQ); it is designed to categorize individuals into low, moderate, or high fall-risk categories to determine appropriate management pathways. A predictive model for probability of fall risk, based on previous research, was used to determine concurrent validity of the FSRI. Results: The FSRA placed 79% of participants into the low-risk category, whereas the predictive model found the probability of fall risk to range from 0.04 to 0.74, with a mean of 0.35 (SD 0.25). No statistically significant correlation was found between the FSRA and the predictive model for probability of fall risk (Spearman's ρ=0.35, p=0.06). Conclusion: The FSRA lacks concurrent validity relative to to a previously established model of fall risk and appears to over-categorize individuals into the low-risk group. Further research on the FSRA as an adequate tool to screen community-dwelling older adults for fall risk is recommended. PMID:24381379

Etudes sur le Portugal au Temps de l'Humanisme

Directory of Open Access Journals (Sweden)

J. Cruz Costa

1953-06-01

Full Text Available BATAILLON (Marcel. — Etudes sur le Portugal au Temps de l'Humanisme.  Acta Universitatis Conimbrigencis, 1952, 309 pp. (Primeiro Parágrafo do Artigo O Prof. Marcel Bataillon, erudito dos mais inteligentes da França atual, autor de uma obra que é hoje impr:scindível para quem pretenda estudar o humanismo renascentista na Espanha ou em Portugal, diríamos melhor, talvez: para quem pretenda estudar o Humanismo e a Renascença, — acaba de publicar, na coleção Acta Universitatis Conimbrigencis, êste volume no qual reune alguns trabalhos da mais alta importância para o conhecimento de muitos aspectos da vida espiritual portuguêsa do século XVI.

Nurses' Perceptions of Implementing Fall Prevention Interventions to Mitigate Patient-Specific Fall Risk Factors.

Science.gov (United States)

Wilson, Deleise S; Montie, Mary; Conlon, Paul; Reynolds, Margaret; Ripley, Robert; Titler, Marita G

2016-08-01

Evidence-based (EB) fall prevention interventions to mitigate patient-specific fall risk factors are readily available but not routinely used in practice. Few studies have examined nurses' perceptions about both the use of these EB interventions and implementation strategies designed to promote their adoption. This article reports qualitative findings of nurses' perceptions about use of EB fall prevention interventions to mitigate patient-specific fall risks, and implementation strategies to promote use of these interventions. The findings revealed five major themes: before-study fall prevention practices, use of EB fall prevention interventions tailored to patient-specific fall risk factors, beneficial implementation strategies, overall impact on approach to fall prevention, and challenges These findings are useful to guide nurses' engagement and use of EB fall prevention practices tailored to patient-specific fall risk factors. © The Author(s) 2016.

The development of a very high stability electrostatic generator (1962); Etude et realisation d'un generateur electrostatique a tres haute stabilite (1962)

Energy Technology Data Exchange (ETDEWEB)

Jonckheere, R E.L. [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

1962-07-01

This thesis deals with the study of an electrostatic high voltage generator having a voltage stability of the order of 10{sup -6} per minute. This equipment should be very useful in electron microscopy. The electrostatic generator is studied as a control system element: transfer function, parasitic signals and noise are determined and a mathematical model is proposed. A theoretical study of the open loop transfer function, stability, transient response, voltage stabilization of five different control systems shows which one should be able to fulfill the requirements There follows a detailed study of drift, a description of the actual system and performance data. (author) [French] Cette etude concerne un generateur electrostatique capable de fournir une tres haute tension continue dont la stabilite relative est de l'ordre de 10{sup -6} pendant une minute. Une telle performance rend cet appareillage tres utile en microscopie electronique. La generatrice electrostatique est etudiee en tant qu'element d'un systeme asservi: on determine successivement la fonction de transfert, les perturbations, le bruit de fond et le modele mathematique. L'etude de cinq differents circuits de regulation en ce qui concerne leur fonction de transfert, stabilite, reponse en regime transitoire, attenuation des perturbations, permettra de choisir le systeme qui semble le mieux repondre aux exigences. Viennent ensuite une etude detaillee de la derive, la description de la realisation pratique et les resultats de mesure. (auteur)

Meteorite falls in Africa

Science.gov (United States)

Khiri, Fouad; Ibhi, Abderrahmane; Saint-Gerant, Thierry; Medjkane, Mohand; Ouknine, Lahcen

2017-10-01

The study of meteorites provides insight into the earliest history of our solar system. From 1800, about the year meteorites were first recognized as objects falling from the sky, until December 2014, 158 observed meteorite falls were recorded in Africa. Their collected mass ranges from 1.4 g to 175 kg with the 1-10 kg cases predominant. The average rate of African falls is low with only one fall recovery per 1.35-year time interval (or 0.023 per year per million km2). This African collection is dominated by ordinary chondrites (78%) just like in the worldwide falls. The seventeen achondrites include three Martian meteorite falls (Nakhla of Egypt, Tissint of Morocco and Zagami of Nigeria). Observed Iron meteorite falls are relatively rare and represent only 5%. The falls' rate in Africa is variable in time and in space. The number of falls continues to grow since 1860, 80% of which were recovered during the period between 1910 and 2014. Most of these documented meteorite falls have been recovered from North-Western Africa, Eastern Africa and Southern Africa. They are concentrated in countries which have a large surface area and a large population with a uniform distribution. Other factors are also favorable for observing and collecting meteorite falls across the African territory, such as: a genuine meteorite education, a semi-arid to arid climate (clear sky throughout the year most of the time), croplands or sparse grasslands and possible access to the fall location with a low percentage of forest cover and dense road network.

Crushing method for nuclear fuel powder

International Nuclear Information System (INIS)

Hasegawa, Shin-ichi; Tsuchiya, Haruo.

1997-01-01

A crushing medium is contained in mill pots disposed at the circumferential periphery of a main axis. The diameter of each mill pot is determined such that powdery nuclear fuels containing aggregated powders and ground and mixed powders do not reach criticality. A plurality of mill pots are revolved in the direction of the main axis while each pots rotating on its axis. Powdery nuclear fuels containing aggregated powders are conveyed to a supply portion of the moll pot, and an inert gas is supplied to the supply portion. The powdery nuclear fuels are supplied from the supply portion to the inside of the mill pots, and the powdery nuclear fuels containing aggregated powders are crushed by centrifugal force caused by the rotation and the revolving of the mill pots by means of the crushing medium. UO 2 powder in uranium oxide fuels can be crushed continuously. PuO 2 powder and UO 2 powder in MOX fuels can be crushed and mixed continuously. (I.N.)

Preventing falls and fractures.

Science.gov (United States)

Ulfarsson, J; Robinson, B E

1994-11-01

One of four persons over age 65 in the community falls; those over age 75 in institutions fall more frequently. Falls, a complex phenomena suggesting present disease and predicting future disability, are caused by interactions between the environment and dynamic balance which is determined by the quality of sensory input, central processing, and motor responses. Clinical factors which predispose to falling often produce observable disturbances in gait and balance, making observation critical in assessment. Acute illness and drug therapy produce particularly preventable falls. Therapeutic exercise and environmental modification for safety are the clinical interventions most likely to successfully prevent fall-related injury.

A Successful ED Fall Risk Program Using the KINDER 1 Fall RiskAssessment Tool.

Science.gov (United States)

Townsend, Ann B; Valle-Ortiz, Marisol; Sansweet, Tracy

2016-11-01

Emergency nurses did not perform falls risk assessments routinely on our ED patients; the instrument used was aimed at inpatients. We identified a need to revise fall assessment practices specific to our emergency department. The purpose of the performance improvement project was to reduce ED falls and evaluate the use of an ED-specific fall risk tool, the KINDER 1 Fall Risk Assessment. The plan was to establish fall risk assessment practices at point of ED entry and to decrease total falls. We retrospectively reviewed ED fall data for each quarter of 2013, which included risk assessments scores, the total number of falls, and the circumstances of each fall. Using Kotter's framework to guide a successful change process, we implemented the KINDER 1 to assess fall risk. During the first 4 weeks of the project, 937 patients (27%) were identified as high risk for falls using the KINDER 1. During the subsequent 3 quarters, the total number of falls decreased; reported falls without injuries dropped from 0.21 to 0.07 per 1000 patients, and falls with injuries were reduced from 0.21 to 0.0 per 1000 patients. The results of this project represented a valuable step toward achieving our goal to keep ED patients safe from injuries as a result of falls. The findings add to the body of nursing knowledge on the application of clinical-based performance improvement projects to improve patient outcomes and to provide data on the use of the KINDER 1 tool, which has not been extensively tested. Copyright © 2016 Emergency Nurses Association. Published by Elsevier Inc. All rights reserved.

Ultrafine hydrogen storage powders

Science.gov (United States)

Anderson, Iver E.; Ellis, Timothy W.; Pecharsky, Vitalij K.; Ting, Jason; Terpstra, Robert; Bowman, Robert C.; Witham, Charles K.; Fultz, Brent T.; Bugga, Ratnakumar V.

2000-06-13

A method of making hydrogen storage powder resistant to fracture in service involves forming a melt having the appropriate composition for the hydrogen storage material, such, for example, LaNi.sub.5 and other AB.sub.5 type materials and AB.sub.5+x materials, where x is from about -2.5 to about +2.5, including x=0, and the melt is gas atomized under conditions of melt temperature and atomizing gas pressure to form generally spherical powder particles. The hydrogen storage powder exhibits improved chemcial homogeneity as a result of rapid solidfication from the melt and small particle size that is more resistant to microcracking during hydrogen absorption/desorption cycling. A hydrogen storage component, such as an electrode for a battery or electrochemical fuel cell, made from the gas atomized hydrogen storage material is resistant to hydrogen degradation upon hydrogen absorption/desorption that occurs for example, during charging/discharging of a battery. Such hydrogen storage components can be made by consolidating and optionally sintering the gas atomized hydrogen storage powder or alternately by shaping the gas atomized powder and a suitable binder to a desired configuration in a mold or die.

Electrochemical behaviors of wax-coated Li powder/Li 4Ti 5O 12 cells

Science.gov (United States)

Park, Han Eol; Seong, Il Won; Yoon, Woo Young

The wax-coated Li powder specimen was effectively synthesized using the drop emulsion technique (DET). The wax layer on the powder was verified by SEM, Focused Ion Beam (FIB), EDX and XPS. The porosity of a sintered wax-coated Li electrode was measured by linear sweep voltammetry (LSV) and compared with that of a bare, i.e., un-coated Li electrode. The electrochemical behavior of the wax-coated Li powder anode cell was examined by the impedance analysis and cyclic testing methods. The cyclic behavior of the wax-coated Li powder anode with the Li 4Ti 5O 12 (LTO) cathode cell was examined at a constant current density of 0.35 mA cm -2 with the cut-off voltages of 1.2-2.0 V at 25 °C. Over 90% of the initial capacity of the cell remained even after the 300th cycle. The wax-coated Li powder was confirmed to be a stable anode material.

Predictive value of stabilometry and fear of falling on falls in postmenopausal women.

Science.gov (United States)

Hita-Contreras, F; Martínez-Amat, A; Lomas-Vega, R; Álvarez, P; Aránega, A; Martínez-López, E; Mendoza, N

2013-10-01

Falls are one of the leading causes of fractures and impaired quality of life in the elderly, and they are related to balance deficit and to fear of falls. The purpose of our study is to evaluate predictors of falls in the 50-65-year-old postmenopausal population. A prospective cohort study was conducted on 96 postmenopausal women. Fear of falling and postural stability were assessed by using the FES-I (Falls Efficacy Scale-International) and a force platform, respectively. Fall frequency was determined in the 12-month follow-up study period. Multivariate logistic regression was used to identify predictive factors of falls. Fear of falls, the FES-I scale and four stabilometric parameters, specifically under eyes-closed condition, were significantly higher in the group of fallers. The root mean square amplitude in the medial-lateral direction with eyes closed (RMSXec) (odds ratio 5.1, 95% confidence interval (CI) 1.6-15.5, p = 0.004) and FES-I (odds ratio 3.4, 95% CI 1.1-10.5, p = 0.026) were the best independent predictive factors of the risk of falling. RMSXec > 0.133 was the best predictive factor for falls in our group of 50-65-year-old postmenopausal women studied, and a FES-I score > 20 could predict falls in this population.

iFall: an Android application for fall monitoring and response.

Science.gov (United States)

Sposaro, Frank; Tyson, Gary

2009-01-01

Injuries due to falls are among the leading causes of hospitalization in elderly persons, often resulting in a rapid decline in quality of life or death. Rapid response can improve the patients outcome, but this is often lacking when the injured person lives alone and the nature of the injury complicates calling for help. This paper presents an alert system for fall detection using common commercially available electronic devices to both detect the fall and alert authorities. We use an Android-based smart phone with an integrated tri-axial accelerometer. Data from the accelerometer is evaluated with several threshold based algorithms and position data to determine a fall. The threshold is adaptive based on user provided parameters such as: height, weight, and level of activity. The algorithm adapts to unique movements that a phone experiences as opposed to similar systems which require users to mount accelerometers to their chest or trunk. If a fall is suspected a notification is raised requiring the user's response. If the user does not respond, the system alerts pre-specified social contacts with an informational message via SMS. If a contact responds the system commits an audible notification, automatically connects, and enables the speakerphone. If a social contact confirms a fall, an appropriate emergency service is alerted. Our system provides a realizable, cost effective solution to fall detection using a simple graphical interface while not overwhelming the user with uncomfortable sensors.

Study of Velocity and Materials on Tribocharging of Polymer Powders for Powder Coating Applications

Science.gov (United States)

Biris, Alex S.; Trigwell, Steve; Sims, Robert A.; Mazumder, Malay K.

2005-01-01

Electrostatic powder deposition is widely used in a plethora of industrial-applications ranging from the pharmaceutical and food.industries, to farm equipment and automotive applications. The disadvantages of this technique are possible back corona (pin-like formations) onset and the Faraday penetration limitation (when the powder does not penetrate in some recessed areas). A possible solution to overcome these problems is to use tribochargers to electrostatically charge the powder. Tribocharging, or contact charging while two materials are in contact, is related to the work function difference between the contacting materials and generates bipolarly charged particles. The generation of an ion-free powder cloud by tribocharging with high bipolar charge and an overall charge density of almost zero, provides a better coverage of the recessed areas. In this study, acrylic and epoxy powders were fluidized and charged by passing through stainless steel, copper, aluminum, and polycarbonate static mixers, respectively. The particle velocity was varied to determine its effect on the net charge-to-mass ratio (QIM) acquired by the powders. In general, the Q/M increases rapidly when the velocity was increased from 1.5 to 2.5 m/s, remaining almost constant for higher velocities. Charge separation experiments showed bipolar charging for all chargers.

Falls in institutions for older adults: characterization of fall occurrences and associated risk factors

Directory of Open Access Journals (Sweden)

Cristina Rosa Soares Lavareda Baixinho

2015-12-01

Full Text Available Falls are the main accident for older adults, with consequences on functionality. Older adults impose restrictions or have restrictions imposed on their activities for fear of new falls. This prospective longitudinal study was conducted with 104 institutionalized older adults during six months with the following goals: to determine the prevalence of falls, to characterize the falls according to place, time, resulting injuries, supervision of the older adult, action performed at the time of the fall, and to relate the occurrence of the fall to the risk of falling, medical diagnoses, number of medications in use, type of medication, degree of dependency, age, and gender. The prevalence of falls was 37.5%, and they happened mostly in the bedroom, while walking after getting up from the bed. Those under risk in the Morse Fall Scale (p=0.034 and on sedatives (p=0.007 face a higher prevalence of falls. This study enables the possibility of making suggestions for practice, training and investigation.

The Neighborhood Environment: Perceived Fall Risk, Resources, and Strategies for Fall Prevention.

Science.gov (United States)

Chippendale, Tracy; Boltz, Marie

2015-08-01

To explore the experience of older adults in their neighborhood in relation to perceived fall risk, fear of falling (FOF), and resources/strategies for fall prevention. Fourteen older adults, 65 years of age and older from 3 urban senior centers, participated in this qualitative study. The semistructured interview guidelines and background questionnaire were developed by the researchers based on the literature and an existing measure of walkability. Both tools were refined based on pilot interviews with seniors. Collaizzi's phenomenological method was used for data analysis. Five themes emerged from the data: (a) The built environment contributes to perceived fall risk and FOF, (b) personal strategies used to adapt to perceived neighborhood fall risks-behavioral approaches, (c) resources for physical activity and safety, (d) barriers to physical activity and exercise, and (e) neighborhood features as a motivator. Urban-dwelling seniors perceive that neighborhood features contribute to or mitigate fall risk and FOF. Behavioral strategies are used by seniors to prevent outdoor falls. The findings can help clinicians develop targeted fall prevention interventions for well elders and help urban planners to design and retrofit urban environments to reduce fall risk. © The Author 2014. 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.

Characteristics and fall experiences of older adults with and without fear of falling outdoors.

Science.gov (United States)

Chippendale, Tracy; Lee, Chang Dae

2018-06-01

Using a theoretical model that combines an ecological perspective and Bandura's theory of self-efficacy as a guide, we sought to compare experiences and characteristics of community dwelling older adults with and without concern about falling outdoors. A survey of randomly selected community dwelling older adults across NYC (N = 120) was conducted using the outdoor falls questionnaire. Descriptive quantitative analyses of participant characteristics were conducted for all participants and for those with and without concern about falling outside. Conventional content analysis using two coders was employed to examine outdoor fall experiences for each group. A mixed methods matrix was used to integrate qualitative and quantitative findings. Some participant characteristics were more common among those with a concern about falling outside such as decreased functional status, female gender, and number of prior outdoor falls. As per descriptions of outdoor fall experiences, participants with concern were more likely to report a fall while climbing stairs or stepping up a curb, describe an intrinsic factor as a cause of their fall, use an injury prevention strategy during the fall, sustain a moderate to severe injury, seek medical attention, have had an ambulance called, require help to get up, and describe implementation of a behavioral change after the fall. Differences exist in participant characteristics and outdoor fall experiences of those with and without concern about falling outside. The proposed model can be used to understand fear of falling outdoors and can help to inform the target population and content of intervention programs.

Effects of a multifactorial fall prevention program on fall incidence and physical function in community-dwelling older adults with risk of falls.

Science.gov (United States)

Lee, Hsuei-Chen; Chang, Ku-Chou; Tsauo, Jau-Yih; Hung, Jen-Wen; Huang, Yu-Ching; Lin, Sang-I

2013-04-01

To evaluate effects of a multifactorial fall prevention program on fall incidence and physical function in community-dwelling older adults. Multicenter randomized controlled trial. Three medical centers and adjacent community health centers. Community-dwelling older adults (N=616) who have fallen in the previous year or are at risk of falling. After baseline assessment, eligible subjects were randomly allocated into the intervention group (IG) or the control group (CG), stratified by the Physiological Profile Assessment (PPA) fall risk level. The IG received a 3-month multifactorial intervention program including 8 weeks of exercise training, health education, home hazards evaluation/modification, along with medication review and ophthalmology/other specialty consults. The CG received health education brochures, referrals, and recommendations without direct exercise intervention. Primary outcome was fall incidence within 1 year. Secondary outcomes were PPA battery (overall fall risk index, vision, muscular strength, reaction time, balance, and proprioception), Timed Up & Go (TUG) test, Taiwan version of the International Physical Activity Questionnaire, EuroQol-5D, Geriatric Depression Scale (GDS), and the Falls Efficacy Scale-International at 3 months after randomization. Participants were 76±7 years old and included low risk 25.6%, moderate risk 25.6%, and marked risk 48.7%. The cumulative 1-year fall incidence was 25.2% in the IG and 27.6% in the CG (hazard ratio=.90; 95% confidence interval, .66-1.23). The IG improved more favorably than the CG on overall PPA fall risk index, reaction time, postural sway with eyes open, TUG test, and GDS, especially for those with marked fall risk. The multifactorial fall prevention program with exercise intervention improved functional performance at 3 months for community-dwelling older adults with risk of falls, but did not reduce falls at 1-year follow-up. Fall incidence might have been decreased simultaneously in both

Plasma technology for powder particles

Energy Technology Data Exchange (ETDEWEB)

Kranz, E. (Technische Hochschule, Ilmenau (German Democratic Republic))

1983-03-01

A survey is given of principles and applications of plasma spraying and of powder transformation and generation in plasma considering spheroidization, grain size transformation, powder particle formation, powder reduction, and melting within the power range of 10/sup 3/ to 10/sup 7/ W. The products are applied in many industrial fields such as nuclear engineering, hard metal production, metallurgy, catalysis, and semiconductor techniques.

How Do Community-Dwelling Persons with Alzheimer Disease Fall Falls in the FINALEX Study

Directory of Open Access Journals (Sweden)

Niko M. Perttila

2017-06-01

Full Text Available Background: People with dementia are at high risk for falls. However, little is known of the features causing falls in Alzheimer disease (AD. Our aim was to investigate how participants with AD fall. Methods: In the FINALEX (Finnish Alzheimer Disease Exercise Trial study, participants’ (n = 194 falls were followed up for 1 year by diaries kept by their spouses. Results: The most common reason for falls (n = 355 was stumbling (n = 61. Of the falls, 123 led to injuries, 50 to emergency department visits, and 13 to fractures. The participants without falls (n = 103 were younger and had milder dementia than those with 1 (n = 34 or ≥2 falls (n = 57. Participants with a Mini Mental State Examination score of around 10 points were most prone to fall. In adjusted regression models, good nutritional status, good physical functioning, and use of antihypertensive medication (incident rate ratio [IRR] 0.68, 95% confidence interval [CI] 0.54–0.85 protected against falls, whereas fall history (IRR 2.71, 95% CI 2.13–3.44, osteoarthritis, diabetes mellitus, chronic obstructive pulmonary disease, higher number of drugs, drugs with anticholinergic properties, psychotropics, and opioids (IRR 4.27, 95% CI 2.92–6.24 were risk factors for falls. Conclusions: Our study provides a detailed account on how and why people with AD fall, suggesting several risk and protective factors.

Predicting falls using two instruments (the Hendrich Fall Risk Model and the Morse Fall Scale) in an acute care setting in Lebanon.

Science.gov (United States)

Nassar, Nada; Helou, Nancy; Madi, Chantal

2014-06-01

To assess the predictive value of two instruments (the Morse Fall Scale (MFS) and the Heindrich II Fall Risk Model (HFRM)] in a Middle Eastern country (Lebanon) and to evaluate the factors that are related to falls. A prospective observational cross-sectional design was used. Falls and fall-related injuries in the acute care settings contribute a substantial health and economic burden on patients and organisations. Preventing falls is a priority for most healthcare organisations. While the risk of falling cannot be eliminated, it can be significantly reduced through accurate assessment of patients' risk of falling. Data from 1815 inpatients at the American University of Beirut Medical Center (AUBMC) in Lebanon were evaluated using two instruments to predict falls: the MFS and the HFRM. The incidence of falls was 2·7% in one year. The results indicate that while the instruments were significantly correlated, the HFRM was more sensitive in predicting falls than the MFS. The internal consistency of both scales was moderate, but inter-rater reliability was high. Patients using antiepileptic drugs and assistance devises had higher odds of falling. Although both instruments were easy to use in a Middle Eastern country, the HFRM rather than the MFS is recommended for inpatients in an acute care setting as it had higher sensitivity and specificity. It is recommended that while the HFRM had adequate sensitivity, it is not seamless, and as such, nurses should not rely entirely on it. Rather, nurses should use their expert clinical judgement, their ethical obligations and cultural considerations to implement a safer environment of care for the patient. © 2013 John Wiley & Sons Ltd.

Fall Enrollment Report. 2014

Science.gov (United States)

Iowa Department of Education, 2014

2014-01-01

This report summarizes and analyzes fall enrollment in Iowa's community colleges. Each year, Iowa's 15 community colleges submit data on enrollment on the 10th business day of the fall semester. Some highlights from this report include: (1) Fall 2014 enrollment was 93,772 students--a decline of 0.49 percent from last fall; (2) Enrollment continues…

Students fall for Fall Meeting

Science.gov (United States)

Smedley, Kara

2012-02-01

From Boston to Beijing, thousands of students traveled to San Francisco for the 2011 AGU Fall Meeting. Of those who participated, 183 students were able to attend thanks to AGU's student travel grant program, which assists students with travel costs and seeks to enrich the meeting through ethnic and gender diversity. Students at Fall Meeting enjoyed a variety of programs and activities designed to help them better network with their peers, learn about new fields, and disseminate their research to the interested public. More than 800 students attended AGU's first annual student mixer, sharing drinks and ideas with fellow student members and future colleagues as well as forging new friendships and intellectual relationships.

Predictive Simulation of Process Windows for Powder Bed Fusion Additive Manufacturing: Influence of the Powder Bulk Density.

Science.gov (United States)

Rausch, Alexander M; Küng, Vera E; Pobel, Christoph; Markl, Matthias; Körner, Carolin

2017-09-22

The resulting properties of parts fabricated by powder bed fusion additive manufacturing processes are determined by their porosity, local composition, and microstructure. The objective of this work is to examine the influence of the stochastic powder bed on the process window for dense parts by means of numerical simulation. The investigations demonstrate the unique capability of simulating macroscopic domains in the range of millimeters with a mesoscopic approach, which resolves the powder bed and the hydrodynamics of the melt pool. A simulated process window reveals the influence of the stochastic powder layer. The numerical results are verified with an experimental process window for selective electron beam-melted Ti-6Al-4V. Furthermore, the influence of the powder bulk density is investigated numerically. The simulations predict an increase in porosity and surface roughness for samples produced with lower powder bulk densities. Due to its higher probability for unfavorable powder arrangements, the process stability is also decreased. This shrinks the actual parameter range in a process window for producing dense parts.

Falls and Fall Prevention in Older Adults With Early-Stage Dementia: An Integrative Review.

Science.gov (United States)

Lach, Helen W; Harrison, Barbara E; Phongphanngam, Sutthida

2017-05-01

Older adults with mild cognitive impairment (MCI) and early-stage dementia have an increased risk of falling, with risks to their health and quality of life. The purpose of the current integrative review was to evaluate evidence on fall risk and fall prevention in this population. Studies were included if they examined falls or fall risk factors in older adults with MCI or early-stage dementia, or reported interventions in this population; 40 studies met criteria. Evidence supports the increased risk of falls in individuals even in the early stages of dementia or MCI, and changes in gait, balance, and fear of falling that may be related to this increased fall risk. Interventions included exercise and multifactorial interventions that demonstrated some potential to reduce falls in this population. Few studies had strong designs to provide evidence for recommendations. Further study in this area is warranted. [Res Gerontol Nurs. 2017; 10(03):139-148.]. Copyright 2016, SLACK Incorporated.

Minimum ignition energy of nano and micro Ti powder in the presence of inert nano TiO₂ powder.

Science.gov (United States)

Chunmiao, Yuan; Amyotte, Paul R; Hossain, Md Nur; Li, Chang

2014-06-15

The inerting effect of nano-sized TiO2 powder on ignition sensitivity of nano and micro Ti powders was investigated with a Mike 3 apparatus. "A little is not good enough" is also suitable for micro Ti powders mixed with nano-sized solid inertants. MIE of the mixtures did not significantly increase until the TiO2 percentage exceeded 50%. Nano-sized TiO2 powders were ineffective as an inertant when mixed with nano Ti powders, especially at higher dust loadings. Even with 90% nano TiO2 powder, mixtures still showed high ignition sensitivity because the statistic energy was as low as 2.1 mJ. Layer fires induced by ignited but unburned metal particles may occur for micro Ti powders mixed with nano TiO2 powders following a low level dust explosion. Such layer fires could lead to a violent dust explosion after a second dispersion. Thus, additional attention is needed to prevent metallic layer fires even where electric spark potential is low. In the case of nano Ti powder, no layer fires were observed because of less flammable material involved in the mixtures investigated, and faster flame propagation in nanoparticle clouds. Copyright © 2014 Elsevier B.V. All rights reserved.

Exploring the relationship between fall risk-increasing drugs and fall-related fractures.

Science.gov (United States)

De Winter, Sabrina; Vanwynsberghe, Sarah; Foulon, Veerle; Dejaeger, Eddy; Flamaing, Johan; Sermon, An; Van der Linden, Lorenz; Spriet, Isabel

2016-04-01

Hospital admissions due to fall-related fractures are a major problem in the aging population. Several risk factors have been identified, including drug use. Most studies often retrieved prescription-only drugs from national databases. These are associated with some limitations as they do not always reliably reproduce the complete patient's active drug list. To evaluate the association between the number of FRIDs intake identified by a standardised medication reconciliation process and a fall-related fracture leading to a hospital admission in older adults. The first cohort has been recruited from one traumatology ward of a tertiary teaching hospital in Belgium and the second cohort has been recruited from 11 community pharmacies in Belgium. A prospective study with two individually matched cohorts was performed. Adult patients (≥75 years) admitted with an injury due to a fall were included in the first cohort (faller group). The second cohort consisted of patients who did not suffer from a fall within the last 6 months (non-faller group). Matching was performed for age, gender, place of residence and use of a walking aid. In both groups, clinical pharmacists and undergraduate pharmacy students obtained the medication history, using a standardised approach. A list of drugs considered to increase the risk of falling was created. It included cardiovascular drugs and drugs acting on the nervous system. A linear mixed model was used to compare the number of fall risk-increasing drugs between fallers and non-fallers. The number of fall risk-increasing drugs in a faller versus a non-faller group. Sixty-one patients were matched with 121 non-fallers. Patients received on average 3.1 ± 2.1 and 3.2 ± 1.8 fall risk-increasing drugs in the faller and in the non-faller group, respectively. The mean number of fall risk-increasing drugs was comparable in both groups (p = 0.844), even after adjusting for alcohol consumption, fear of falling, vision and foot problems (p = 0

Ultrasonic wave propagation in powders

Science.gov (United States)

Al-Lashi, R. S.; Povey, M. J. W.; Watson, N. J.

2018-05-01

Powder clumps (cakes) has a significant effect on the flowability and stability of powders. Powder caking is mainly caused by moisture migration due to wetting and environmental (temperature and humidity) changes. The process of moisture migration caking involves creating liquid bridges between the particles during condensation which subsequently harden to form solid bridges. Therefore, an effective and reliable technique is required to quantitatively and non-invasively monitor caking kinetics and effective stiffness. This paper describes two ultrasonic instruments (ultrasonic velocity pulse and airborne ultrasound systems) that have been used to monitor the caking phenomenon. Also, it discusses the relationship between the ultrasonic velocity and attenuation measurements and tracking caking kinetics and the effective stiffness of powders.

Falls incidence underestimates the risk of fall-related injuries in older age groups : a comparison with the FARE (Falls risk by Exposure)

NARCIS (Netherlands)

Etman, Astrid; Wijlhuizen, Gert Jan; van Heuvelen, Marieke J. G.; Chorus, Astrid; Hopman-Rock, Marijke

Background: up till now, the risk of falls has been expressed as falls incidence (i.e. the number of falls or fallers per 100 person-years). However, the risk of an accident or injury is the probability of having an accident or injury per unit of exposure. The FARE ( Falls risk by Exposure) is a

Falls incidence underestimates the risk of fall-related injuries in older age groups: a comparison with the FARE (Falls risk by Exposure)

NARCIS (Netherlands)

Etman, A.; Wijlhuizen, G.J.; van Heuvelen, M.J.G.; Chorus, A.M.J.; Hopman-Rock, M.

2012-01-01

Background: up till now, the risk of falls has been expressed as falls incidence (i.e. the number of falls or fallers per 100 person-years). However, the risk of an accident or injury is the probability of having an accident or injury per unit of exposure. The FARE (Falls risk by Exposure) is a

Falls incidence underestimates the risk of fall-related injuries in older age groups: A comparison with the FARE (Falls risk by exposure)

NARCIS (Netherlands)

Etman, A.; Wijlhuizen, G.J.; Heuvelen, M.J.G. van; Chorus, A.; Hopman-Rock, M.

2012-01-01

Background: up till now, the risk of falls has been expressed as falls incidence (i.e. the number of falls or fallers per 100 person-years). However, the risk of an accident or injury is the probability of having an accident or injury per unit of exposure. The FARE (Falls risk by Exposure) is a

Falls, a fear of falling and related factors in older adults with complex chronic disease.

Science.gov (United States)

Lee, JuHee; Choi, MoonKi; Kim, Chang Oh

2017-12-01

To identify factors influencing falls and the fear of falling among older adults with chronic diseases in Korea. The fear of falling and falls in older adults are significant health problems towards which healthcare providers should direct their attention. Further investigation is needed to improve nursing practice specifically decreasing risk of falls and the fear of falling in Korea. Descriptive, cross-sectional survey. A convenience sample of 108 patients was recruited at the geriatric outpatient department of a tertiary hospital in Seoul, Korea. Demographic characteristics, comorbidities, medication use, fall history, level of physical activity, activities of daily living, mobility, muscle strength, and a fear of falling were investigated. Student's t tests, chi-square tests and multiple linear regressions were used in statistical analysis. Thirty-six participants (33.3%) among 108 subjects reported experiencing ≥1 falls in the past year. Marital status and the use of antipsychotics were associated with falls, while other factors were not significantly related to falls. Only benign prostatic hypertrophy and polypharmacy were significantly related to the fear of falling in the analysis of the relationships between chronic disease, medication use and fear of falling. In the regression model, the number of comorbidities, level of physical activity, activities of daily living and mobility were predictors of a fear of falling. Medication use was marginally significant, in the model. Increasing physical activity, functional fitness and physical independence is important to decrease the fear of falling, and to encourage active and healthy lives in older adults. The findings from this study provide evidence for the development of nursing interventions for older adults. We recommend early screening for a fear of falling and nursing interventions to decrease the fear of falling through enhancing physical activity level and function. © 2017 John Wiley & Sons Ltd.

Association between obesity, risk of falls and fear of falling in older women

Directory of Open Access Journals (Sweden)

Silvia Gonçalves Ricci Neri

2017-11-01

Full Text Available DOI: http://dx.doi.org/10.5007/1980-0037.2017v19n4p450   The aim of this cross-sectional study was to investigate the association between obesity, risk of falls and fear of falling in older women. Two hundred and twenty-six volunteers (68.05 ± 6.22 years, 68.06 ± 11.79 kg, 1.56 ± 0.06 m were classified as normal weight, overweight or obese, according to the body mass index. Risk of falls and fear of falling were evaluated using QuickScreen Clinical Falls Risk Assessment and Falls Efficiency Scale – International (FES-I, respectively. Comparisons between groups were conducted using Chi-square and ANOVA One-way tests. The significance level was set at p< 0.05. Obesity was associated with greater probability of falls (p< 0.001, which may be partly explained by decreased muscle strength (p< 0.001 and reaction time (p< 0.001. In addition, significant differences between groups was observed in FES-I score (p< 0.01, with obese women showing more pronounced fear of falling (30.10 ± 8.4 than normal weigh (25. 33 ± 7.11, p< 0.01 and overweight subjects (26.97 ± 7.05, p< 0.05. These findings corroborate previous evidence pointing obesity as a major risk factor for falls. Therefore, health professionals dealing with fall prevention should consider the effects of overweight.

Effect of surface energy on powder compactibility.

Science.gov (United States)

Fichtner, Frauke; Mahlin, Denny; Welch, Ken; Gaisford, Simon; Alderborn, Göran

2008-12-01

The influence of surface energy on the compactibility of lactose particles has been investigated. Three powders were prepared by spray drying lactose solutions without or with low proportions of the surfactant polysorbate 80. Various powder and tablet characterisation procedures were applied. The surface energy of the powders was characterized by Inverse Gas Chromatography and the compressibility of the powders was described by the relationship between tablet porosity and compression pressure. The compactibility of the powders was analyzed by studying the evolution of tablet tensile strength with increasing compaction pressure and porosity. All powders were amorphous and similar in particle size, shape, and surface area. The compressibility of the powders and the microstructure of the formed tablets were equal. However, the compactibility and dispersive surface energy was dependent of the composition of the powders. The decrease in tablet strength correlated to the decrease in powder surface energy at constant tablet porosities. This supports the idea that tablet strength is controlled by formation of intermolecular forces over the areas of contact between the particles and that the strength of these bonding forces is controlled by surface energy which, in turn, can be altered by the presence of surfactants.

Randomized control trial for the assessment of the anti-albuminuric effects of topiroxostat in hyperuricemic patients with diabetic nephropathy (the ETUDE study).

Science.gov (United States)

Kato, Sawako; Ando, Masahiko; Mizukoshi, Toshihiro; Nagata, Takanobu; Katsuno, Takayuki; Kosugi, Tomoki; Tsuboi, Naotake; Maruyama, Shoichi

2016-05-01

Proteinuria is an established risk factor for diabetic nephropathy. Recent studies indicate that some xanthine oxidase inhibitors have a renoprotective effect. The aim of this study was to assess whether topiroxostat reduces albuminuria in hyperuricemic patients with diabetic nephropathy and overt proteinuria. The ETUDE study is an ongoing 24-week, multicenter, open-label, randomized (1:1), parallel group study involving hyperuricemic patients with diabetic nephropathy (estimated glomerular filtration rate [eGFR] ≥ 20 mL/min/1.73 m(2)) and overt proteinuria (0.3 ≤ urine protein to creatinine ratio (UPCR) ETUDE trial is the first randomized controlled study of topiroxostat in hyperuricemic patients with diabetic nephropathy and overt proteinuria. We will clarify the pleiotropic function of topiroxostat including an anti-albumiuric effect as well as its effects on safely decreasing serum uric acid levels.

New horizons in fall prevention.

Science.gov (United States)

Lord, Stephen R; Close, Jacqueline C T

2018-04-25

Falls pose a major threat to the well-being and quality of life of older people. Falls can result in fractures and other injuries, disability and fear and can trigger a decline in physical function and loss of autonomy. This article synthesises recent published findings on fall risk and mobility assessments and fall prevention interventions and considers how this field of research may evolve in the future. Fall risk topics include the utility of remote monitoring using wearable sensors and recent work investigating brain activation and gait adaptability. New approaches for exercise for fall prevention including dual-task training, cognitive-motor training with exergames and reactive step training are discussed. Additional fall prevention strategies considered include the prevention of falls in older people with dementia and Parkinson's disease, drugs for fall prevention and safe flooring for preventing fall-related injuries. The review discusses how these new initiatives and technologies have potential for effective fall prevention and improved quality of life. It concludes by emphasising the need for a continued focus on translation of evidence into practice including robust effectiveness evaluations of so that resources can be appropriately targeted into the future.

Masculinity and preventing falls: insights from the fall experiences of men aged 70 years and over.

Science.gov (United States)

Liddle, J L M; Lovarini, Meryl; Clemson, Lindy M; Jang, Haeyoung; Lord, Stephen R; Sherrington, Catherine; Willis, Karen

2018-01-11

To explore men's fall experiences through the lens of masculine identities so as to assist health professionals better engage men in fall prevention programs. Twenty-five men, aged 70-93 years who had experienced a recent fall, participated in a qualitative semi-structured interview. Men's willingness to engage in fall prevention programs taking account of individual contexts and expressions of masculinity, were conceptualised using constant comparative methods. Men's willingness to engage in fall prevention programs was related to their perceptions of the preventability of falls; personal relevance of falls; and age, health, and capability as well as problem-solving styles to prevent falls. Fall prevention advice was rarely given when men accessed the health system at the time of a fall. Contrary to dominant expectations about masculine identity, many men acknowledged fall vulnerability indicating they would attend or consider attending, a fall prevention program. Health professionals can better engage men by providing consistent messages that falls can be prevented; tailoring advice, understanding men are at different stages in their awareness of fall risk and preferences for action; and by being aware of their own assumptions that can act as barriers to speaking with men about fall prevention. Implications for rehabilitation Men accessing the health system at the time of the fall, and during rehabilitation following a fall represent prime opportunities for health professionals to speak with men about preventing falls and make appropriate referrals to community programs. Tailored advice will take account of individual men's perceptions of preventability; personal relevance; perceptions of age, health and capability; and problem-solving styles.

Safety consideration when handling metal powders

CSIR Research Space (South Africa)

Benson, JM

2012-03-01

Full Text Available to some form of irritation or allergic reaction (e.g. dermatitis). In the case of nano-powders, the particles can penetrate the skin and become absorbed into cells in various parts of the body, including the brain � Eye contact, resulting in a... powders, and thus data is often limited to various ailments that have been reported for people working with that particular powder (amongs other things). There are three ways that powders can interact with the body: � Skin contact, which may lead...

Effect of surface coating with magnesium stearate via mechanical dry powder coating approach on the aerosol performance of micronized drug powders from dry powder inhalers.

Science.gov (United States)

Zhou, Qi Tony; Qu, Li; Gengenbach, Thomas; Larson, Ian; Stewart, Peter J; Morton, David A V

2013-03-01

The objective of this study was to investigate the effect of particle surface coating with magnesium stearate on the aerosolization of dry powder inhaler formulations. Micronized salbutamol sulphate as a model drug was dry coated with magnesium stearate using a mechanofusion technique. The coating quality was characterized by X-ray photoelectron spectroscopy. Powder bulk and flow properties were assessed by bulk densities and shear cell measurements. The aerosol performance was studied by laser diffraction and supported by a twin-stage impinger. High degrees of coating coverage were achieved after mechanofusion, as measured by X-ray photoelectron spectroscopy. Concomitant significant increases occurred in powder bulk densities and in aerosol performance after coating. The apparent optimum performance corresponded with using 2% w/w magnesium stearate. In contrast, traditional blending resulted in no significant changes in either bulk or aerosolization behaviour compared to the untreated sample. It is believed that conventional low-shear blending provides insufficient energy levels to expose host micronized particle surfaces from agglomerates and to distribute guest coating material effectively for coating. A simple ultra-high-shear mechanical dry powder coating step was shown as highly effective in producing ultra-thin coatings on micronized powders and to substantially improve the powder aerosolization efficiency.

Baking Powder Wars

OpenAIRE

Civitello, Linda

2017-01-01

How did a mid-nineteenth century American invention, baking powder, replace yeast as a leavening agent and create a culinary revolution as profound as the use of yeast thousands of years ago?The approach was two-pronged and gendered: business archives, U.S. government records and lawsuits revealed how baking powder was created, marketed, and regulated. Women’s diaries and cookbooks—personal, corporate, community, ethnic—from the eighteenth century to internet blogs showed the use women made o...

PRODUCTION OF POROUS POWDER MATERIALS OF SPHERICAL POWDERS OF CORROSION-RESISTANT STEEL

Directory of Open Access Journals (Sweden)

V. N. Kovalevskij

2012-01-01

Full Text Available Production of porous powder materials from spherical powders of corrosion-resistant steel 12Х18н10Т with formation at low pressures 120–140 mpa in the mold with the subsequent activated sintering became possible due to increase of duration of process of spattering and formation of condensate particles (Si–C or (Mo–Si on surface.

Disability is an Independent Predictor of Falls and Recurrent Falls in People with Parkinson's Disease Without a History of Falls: A One-Year Prospective Study.

Science.gov (United States)

Almeida, Lorena R S; Sherrington, Catherine; Allen, Natalie E; Paul, Serene S; Valenca, Guilherme T; Oliveira-Filho, Jamary; Canning, Colleen G

2015-01-01

Predictors of falls in people with Parkinson's disease (PD) who have not previously fallen are yet to be identified. We aimed to identify predictors of all falls and recurrent falls in people with PD who had not fallen in the previous year and to explore the timing of falls in a 12-month follow-up period. Participants with PD (n = 130) were assessed by disease-specific, self-report and balance measures. Falls were recorded prospectively for 12 months. Univariate and multivariate analyses were performed. Kaplan-Meier survival analysis was used to investigate time to falling. Forty participants (31%) had ≥1 fall during follow-up and 21 (16%) had ≥2 falls. Disability, reduced balance confidence and greater concern about falling were associated with ≥1 fall in univariate analyses. Additionally, PD duration and severity, freezing of gait and impaired balance were associated with ≥2 falls (p Disability (Schwab and England scale, Odds Ratio [OR] = 0.56 per 10 points increase; 95% confidence interval [CI] 0.39-0.80; p = 0.002) was associated with ≥1 fall in the final multivariate model (area under the receiver operating characteristic curve [AUC] = 0.65; 95% CI 0.55-0.76; p = 0.005). Disability (Unified Parkinson's Disease Rating Scale activities of daily living, OR = 1.20; 95% CI 1.07-1.34; p = 0.001) and levodopa equivalent dose (OR = 1.11 per 100 mg increase; 95% CI 0.95-1.30; p = 0.19) were associated with ≥2 falls in the final multivariate model (AUC = 0.72; 95% CI 0.60-0.84; p = 0.001). Recurrent fallers experienced their first fall earlier than single fallers (p disability was the strongest single predictor of all falls and recurrent falls.

The history of falls and the association of the timed up and go test to falls and near-falls in older adults with hip osteoarthritis

Directory of Open Access Journals (Sweden)

Faulkner Robert A

2007-07-01

Full Text Available Abstract Background Falling accounts for a significant number of hospital and long-term care admissions in older adults. Many adults with the combination of advancing age and functional decline associated with lower extremity osteoarthritis (OA, are at an even greater risk. The purpose of this study was to describe fall and near-fall history, location, circumstances and injuries from falls in a community-dwelling population of adults over aged 65 with hip OA and to determine the ability of the timed up and go test (TUG to classify fallers and near-fallers. Method A retrospective observational study of 106 older men and women with hip pain for six months or longer, meeting a clinical criteria for the presence of hip OA at one or both hips. An interview for fall and near-fall history and administration of the TUG were administered on one occasion. Results Forty-five percent of the sample had at least one fall in the past year, seventy-seven percent reported occasional or frequent near-falls. The majority of falls occurred during ambulation and ascending or descending steps. Forty percent experienced an injury from the fall. The TUG was not associated with history of falls, but was associated with near-falls. Higher TUG scores occurred for those who were older, less mobile, and with greater number of co-morbidities. Conclusion A high percentage of older adults with hip OA experience falls and near-falls which may be attributed to gait impairments related to hip OA. The TUG could be a useful screening instrument to predict those who have frequent near-falls, and thus might be useful in predicting risk of future falls in this population.

Diagnosis and Tests: Evaluating a Fall or Risk of Falling

Science.gov (United States)

... as a physical therapist, who can evaluate your fall risk. If your healthcare provider concludes that you are ... to check for things that can impact your fall risk, such as electrolyte balance and the possibility of ...

Comparison of blueberry powder produced via foam-mat freeze-drying versus spray-drying: evaluation of foam and powder properties.

Science.gov (United States)

Darniadi, Sandi; Ho, Peter; Murray, Brent S

2018-03-01

Blueberry juice powder was developed via foam-mat freeze-drying (FMFD) and spray-drying (SD) via addition of maltodextrin (MD) and whey protein isolate (WPI) at weight ratios of MD/WPI = 0.4 to 3.2 (with a fixed solids content of 5 wt% for FMFD and 10 wt% for SD). Feed rates of 180 and 360 mL h -1 were tested in SD. The objective was to evaluate the effect of the drying methods and carrier agents on the physical properties of the corresponding blueberry powders and reconstituted products. Ratios of MD/WPI = 0.4, 1.0 and 1.6 produced highly stable foams most suitable for FMFD. FMFD gave high yields and low bulk density powders with flake-like particles of large size that were also dark purple with high red values. SD gave low powder recoveries. The powders had higher bulk density and faster rehydration times, consisting of smooth, spherical and smaller particles than in FMFD powders. The SD powders were bright purple but less red than FMFD powders. Solubility was greater than 95% for both FMFD and SD powders. The FMFD method is a feasible method of producing blueberry juice powder and gives products retaining more characteristics of the original juice than SD. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

[Advances in studies on bear bile powder].

Science.gov (United States)

Zhou, Chao-fan; Gao, Guo-jian; Liu, Ying

2015-04-01

In this paper, a detailed analysis was made on relevant literatures about bear bile powder in terms of chemical component, pharmacological effect and clinical efficacy, indicating bear bile powder's significant pharmacological effects and clinical application in treating various diseases. Due to the complex composition, bear bile powder is relatively toxic. Therefore, efforts shall be made to study bear bile powder's pharmacological effects, clinical application, chemical composition and toxic side-effects, with the aim to provide a scientific basis for widespread reasonable clinical application of bear bile powder.

21 CFR 73.2645 - Aluminum powder.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Aluminum powder. 73.2645 Section 73.2645 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2645 Aluminum powder. (a) Identity and specifications. The color additive aluminum powder shall conform in identity and specifications to the requirements of...

CLAY SOIL STABILISATION USING POWDERED GLASS

Directory of Open Access Journals (Sweden)

J. OLUFOWOBI

2014-10-01

Full Text Available This paper assesses the stabilizing effect of powdered glass on clay soil. Broken waste glass was collected and ground into powder form suitable for addition to the clay soil in varying proportions namely 1%, 2%, 5%, 10% and 15% along with 15% cement (base by weight of the soil sample throughout. Consequently, the moisture content, specific gravity, particle size distribution and Atterberg limits tests were carried out to classify the soil using the ASSHTO classification system. Based on the results, the soil sample obtained corresponded to Group A-6 soils identified as ‘fair to poor’ soil type in terms of use as drainage and subgrade material. This justified stabilisation of the soil. Thereafter, compaction, California bearing ratio (CBR and direct shear tests were carried out on the soil with and without the addition of the powdered glass. The results showed improvement in the maximum dry density values on addition of the powdered glass and with corresponding gradual increase up to 5% glass powder content after which it started to decrease at 10% and 15% powdered glass content. The highest CBR values of 14.90% and 112.91% were obtained at 5% glass powder content and 5mm penetration for both the unsoaked and soaked treated samples respectively. The maximum cohesion and angle of internal friction values of 17.0 and 15.0 respectively were obtained at 10% glass powder content.

Risk of falls after withdrawal of fall-risk-increasing drugs: a prospective cohort study

NARCIS (Netherlands)

van der Velde, Nathalie; Stricker, Bruno H. Ch; Pols, Huib A. P.; van der Cammen, Tischa J. M.

2007-01-01

AIMS: Falling in older persons is a frequent and serious clinical problem. Several drugs have been associated with increased fall risk. The objective of this study was to identify differences in the incidence of falls after withdrawal (discontinuation or dose reduction) of fall-risk-increasing drugs

CVD carbon powders modified by ball milling

Directory of Open Access Journals (Sweden)

Kazmierczak Tomasz

2015-09-01

Full Text Available Carbon powders produced using a plasma assisted chemical vapor deposition (CVD methods are an interesting subject of research. One of the most interesting methods of synthesizing these powders is using radio frequency plasma. This method, originally used in deposition of carbon films containing different sp2/sp3 ratios, also makes possible to produce carbon structures in the form of powder. Results of research related to the mechanical modification of these powders have been presented. The powders were modified using a planetary ball mill with varying parameters, such as milling speed, time, ball/powder mass ratio and additional liquids. Changes in morphology and particle sizes were measured using scanning electron microscopy and dynamic light scattering. Phase composition was analyzed using Raman spectroscopy. The influence of individual parameters on the modification outcome was estimated using statistical method. The research proved that the size of obtained powders is mostly influenced by the milling speed and the amount of balls. Powders tend to form conglomerates sized up to hundreds of micrometers. Additionally, it is possible to obtain nanopowders with the size around 100 nm. Furthermore, application of additional liquid, i.e. water in the process reduces the graphitization of the powder, which takes place during dry milling.

Shock diffraction in alumina powder

International Nuclear Information System (INIS)

Venz, G.; Killen, P.D.; Page, N.W.

1996-01-01

In order to produce complex shaped components by dynamic compaction of ceramic powders detailed knowledge of their response under shock loading conditions is required. This work attempts to provide data on release effects and shock attenuation in 1 μm and 5 μm α-alumina powders which were compacted to between 85 % and 95 % of the solid phase density by the impact of high velocity steel projectiles. As in previous work, the powder was loaded into large cylindrical dies with horizontal marker layers of a contrasting coloured powder to provide a record of powder displacement in the recovered specimens. After recovery and infiltration with a thermosetting resin the specimens were sectioned and polished to reveal the structure formed by the passage of the projectile and shock wave. Results indicate that the shock pressures generated were of the order of 0.5 to 1.4 GPa and higher, with shock velocities and sound speeds in the ranges 650 to 800 m/s and 350 to 400 m/s respectively

The design and development of a complex multifactorial falls assessment intervention for falls prevention: The Prevention of Falls Injury Trial (PreFIT).

Science.gov (United States)

Bruce, Julie; Ralhan, Shvaita; Sheridan, Ray; Westacott, Katharine; Withers, Emma; Finnegan, Susanne; Davison, John; Martin, Finbarr C; Lamb, Sarah E

2017-06-01

This paper describes the design and development of a complex multifactorial falls prevention (MFFP) intervention for implementation and testing within the framework of a large UK-based falls prevention randomised controlled trial (RCT). A complex intervention was developed for inclusion within the Prevention of Falls Injury Trial (PreFIT), a multicentre pragmatic RCT. PreFIT aims to compare the clinical and cost-effectiveness of three alternative primary care falls prevention interventions (advice, exercise and MFFP), on outcomes of fractures and falls. Community-dwelling adults, aged 70 years and older, were recruited from primary care in the National Health Service (NHS), England. Development of the PreFIT MFFP intervention was informed by the existing evidence base and clinical guidelines for the assessment and management of falls in older adults. After piloting and modification, the final MFFP intervention includes seven falls risk factors: a detailed falls history interview with consideration of 'red flags'; assessment of balance and gait; vision; medication screen; cardiac screen; feet and footwear screen and home environment assessment. This complex intervention has been fully manualised with clear, documented assessment and treatment pathways for each risk factor. Each risk factor is assessed in every trial participant referred for MFFP. Referral for assessment is based upon a screening survey to identify those with a history of falling or balance problems. Intervention delivery can be adapted to the local setting. This complex falls prevention intervention is currently being tested within the framework of a large clinical trial. This paper adheres to TIDieR and CONSORT recommendations for the comprehensive and explicit reporting of trial interventions. Results from the PreFIT study will be published in due course. The effectiveness and cost-effectiveness of the PreFIT MFFP intervention, compared to advice and exercise, on the prevention of falls and

Development of a slow mono-kinetic electron source; Etude et realisation d'une source d'electrons lents monocinetiques

Energy Technology Data Exchange (ETDEWEB)

Ballu, Y [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1968-06-01

A comparative study of already existing slow mono-kinetic electron guns shows that those using a 127 degrees electrostatic selector can be improved still further to arrive at the performances obtained with spherical 180 degrees selectors for example. For this reason we have examined the 127 degrees selector theoretically in more detail; it appears that it should be possible to obtain a resolving power better than 30 mV for a current of about 10{sup -10} A, on condition that certain improvements be made to the instrument as normally designed, in particular concerning the entrance and exit slides. As a result, the usual suppressors for the scattered electrons are no longer necessary. The development of this apparatus has been carried out with particular care: the dimensional characteristics are fixed to an accuracy of a few microns, although the instrument can be baked out at 300 C. The experimental results are in excellent agreement with the theoretical predictions: for a current of 10{sup -10} A, the measured resolving power is 24 {+-} 4 mV. The easy detection of the He{sup -} resonance line at 19.3 eV has confirmed the advantages of this apparatus for the study of atomic collisions. (author) [French] L'etude comparative des canons a electrons lents monocinetiques realises jusqu'a present montre que ceux qui utilisent un selecteur electrostatique a 127 degres peuvent etre encore perfectionnes en vue de parvenir aux performances obtenues avec les selecteurs spheriques a 180 degres par exemple. D'ou notre etude theorique approfondie du selecteur a 127 degres qui nous a conduit a esperer une resolution meilleure que 30 mV pour un courant de l'ordre de 10{sup -10} A a condition d'apporter certaines ameliorations a la conception usuelle de cet instrument notamment au niveau des fentes d'entree et de sortie. Par voie de consequence les suppresseurs habituels d'electrons parasites deviennent inutiles. L'etude et la mise au point de l'appareil ont fait l'objet de soins

Relationship Between Perceived Risk of Falling and Adoption of Precautions to Reduce Fall Risk.

Science.gov (United States)

Blalock, Susan J; Gildner, Paula L; Jones, Jennifer L; Bowling, James M; Casteel, Carri H

2016-06-01

To better understand the relationship between perceived risk of falling and awareness and adoption of four specific precautions that older adults have taken to reduce this risk. Cross-sectional. Data were collected in in-person interviews conducted in the homes of study participants. Interviews conducted between March 2011 and September 2013 and lasted an average of 60-90 minutes. A stratified sampling strategy designed to enroll an equal number of homebound and nonhomebound participants was used. All participants (N = 164) were recruited from central North Carolina. Participants were asked about 1-year fall history, perceived risk of falling, restriction of activities because of fear of falling, awareness of four recommended fall prevention behaviors (exercise, annual medication review, bathroom grab bars, safe footwear), and current practice of these behaviors. In bivariate analyses, individuals who were aware of two behaviors recommended to reduce the risk of falling (exercise, use of safe footwear) and had adopted these behaviors perceived their risk of falling as lower than individuals who were aware of the recommended behaviors but had not adopted them. Moreover, in multivariate analyses, individuals who did not know that exercise is recommended to reduce the risk of falling perceived their risk of falling as lower than those who were aware of this recommendation and had adopted it. Individuals were least likely to be aware that medication reviews and exercise are recommended to reduce fall risk. Awareness of behaviors recommended to reduce fall risk appears necessary for adoption of these behaviors to reduce perceived risk. Fall-prevention campaigns should emphasize behaviors where awareness is low. © 2016, Copyright the Authors Journal compilation © 2016, The American Geriatrics Society.

21 CFR 73.1645 - Aluminum powder.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Aluminum powder. 73.1645 Section 73.1645 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1645 Aluminum powder. (a) Identity. (1) The color additive aluminum powder shall be composed of finely divided particles of aluminum prepared from virgin aluminum. It...

21 CFR 73.2647 - Copper powder.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Copper powder. 73.2647 Section 73.2647 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2647 Copper powder. (a) Identity and specifications. The color additive copper powder shall conform in identity and specifications to the requirements of § 73...

Falls in Parkinson's disease.

NARCIS (Netherlands)

Grimbergen, Y.A.M.; Munneke, M.; Bloem, B.R.

2004-01-01

PURPOSE OF REVIEW: To summarize the latest insights into the clinical significance, assessment, pathophysiology and treatment of falls in Parkinson's disease. RECENT FINDINGS: Recent studies have shown that falls are common in Parkinson's disease, even when compared with other fall-prone

Predicting Falls in People with Multiple Sclerosis: Fall History Is as Accurate as More Complex Measures

Directory of Open Access Journals (Sweden)

Michelle H. Cameron

2013-01-01

Full Text Available Background. Many people with MS fall, but the best method for identifying those at increased fall risk is not known. Objective. To compare how accurately fall history, questionnaires, and physical tests predict future falls and injurious falls in people with MS. Methods. 52 people with MS were asked if they had fallen in the past 2 months and the past year. Subjects were also assessed with the Activities-specific Balance Confidence, Falls Efficacy Scale-International, and Multiple Sclerosis Walking Scale-12 questionnaires, the Expanded Disability Status Scale, Timed 25-Foot Walk, and computerized dynamic posturography and recorded their falls daily for the following 6 months with calendars. The ability of baseline assessments to predict future falls was compared using receiver operator curves and logistic regression. Results. All tests individually provided similar fall prediction (area under the curve (AUC 0.60–0.75. A fall in the past year was the best predictor of falls (AUC 0.75, sensitivity 0.89, specificity 0.56 or injurious falls (AUC 0.69, sensitivity 0.96, specificity 0.41 in the following 6 months. Conclusion. Simply asking people with MS if they have fallen in the past year predicts future falls and injurious falls as well as more complex, expensive, or time-consuming approaches.

Effect of additives on the orientation of magnetic Sr-ferrite powders in powder injection molded compacts

Energy Technology Data Exchange (ETDEWEB)

Cho, T.S. [Sangju National Unviersity, Sangju (Korea); Jeung, W.Y. [Korea Institute of Science and Technology, Seoul (Korea)

2001-03-01

The effect of additives on the orientation of magnetic Sr-ferrite powders has been studied during powder injection molding under applied magnetic field for fabricating multi=pole anisotropic sintered Sr-ferrite magnets. The orientation of the Sr-ferrite powders depends sensitively on the fluidity of powder-binder mixture, related to the binder additives and the injection molding temperature, and the magnetic field intensity. The orientation of Sr-ferrite powders is good for the compacts with stearic acid added in the binder system of paraffin wax/ carnauba wax/HDPE, but it is poor of the compacts with silane coupling agent added. The orientation of sr-ferrites higher than 80% is achieved at the following useful conditions; apparent viscosity lower than 2500 poise in 1000 sec {sup -1} shear rate and applied magnetic field higher than 4 kOe. (author). 15 refs., 1 tab., 6 figs.

The interplay between gait, falls and cognition: can cognitive therapy reduce fall risk?

Science.gov (United States)

Segev-Jacubovski, Orit; Herman, Talia; Yogev-Seligmann, Galit; Mirelman, Anat; Giladi, Nir; Hausdorff, Jeffrey M

2011-01-01

In this article, we briefly summarize the incidence and significant consequences of falls among older adults, the insufficient effectiveness of commonly used multifactorial interventions and the evidence linking falls and cognitive function. Recent pharmacologic and nonpharmacologic studies that evaluated the effects of cognitive therapy on fall risk are reviewed. The results of this article illustrate the potential utility of multiple, diverse forms of cognitive therapy for reducing fall risk. The article also indicates that large-scale, randomized controlled trials are warranted and that additional research is needed to better understand the pathophysiologic mechanisms underlying the interplay between human mobility, fall risk and cognitive function. Nonetheless, we suggest that multimodality interventions that combine motor and cognitive therapy should, eventually, be incorporated into clinical practice to enable older adults and patients to move safer and with a reduced fall risk. PMID:21721921

Hydrothermal treatment of coprecipitated YSZ powders

International Nuclear Information System (INIS)

Arakaki, Alexander Rodrigo; Yoshito, Walter Kenji; Ussui, Valter; Lazar, Dolores Ribeiro Ricci

2009-01-01

Zirconia stabilized with 8.5 mol% yttria (YSZ) were synthesized by coprecipitation and resulting gels were hydrothermally treated at 200°C and 220 PSI for 4, 8 and 16 hours. Products were oven dried at 70°C for 24 hours, uniaxially pressed as pellets and sintered at 1500 °C for 1 hour. Powders were characterized for surface area with N 2 gas adsorption, X-ray diffraction, laser diffraction granulometric analysis and scanning and transmission electronic microscopy. Density of ceramics was measured by an immersion method based on the Archimedes principle. Results showed that powders dried at 70°C are amorphous and after treatment has tetragonal/cubic symmetry. Surface area of powders presented a significant reduction after hydrothermal treatment. Ceramics prepared from hydrothermally treated powders have higher green density but sintered pellets are less dense when compared to that made with powders calcined at 800°C for 1 hour due to the agglomerate state of powders. Solvothermal treatment is a promising procedure to enhance density. (author)

Cheese powder as an ingredient in emulsion sausages

DEFF Research Database (Denmark)

Chen, Xiang; Ruiz Carrascal, Jorge; Petersen, Mikael Agerlin

2017-01-01

Different types of cheese powder were added to meat emulsion sausages in order to address its influence on chemical composition, volatile compounds profile and sensory properties, and its potential to reduce salt content through boosting saltiness. Addition of cheese powder to emulsion sausages...... modified their profile of volatile compounds. Blue cheese increased some ketones, alcohols, and esters, while brown cheese brought typical Maillard reaction compounds. Overall, addition of cheese powders to sausages enhanced the intensity of flavour traits. A mixture of hard and blue cheese powder showed...... the highest effect on boosting saltiness, while brown cheese powder showed the strongest umami and meat flavour boosting effect, and sausages with added blue cheese powder showed a more intense aftertaste. Hardness significantly increased due to the addition of blue cheese powder. Addition of cheese powder...

Meanings of Falls and Prevention of Falls According to Rehabilitation Nurses: A Qualitative Descriptive Study.

Science.gov (United States)

Bok, Amy; Pierce, Linda L; Gies, Cheryl; Steiner, Victoria

2016-01-01

Guided by Friedemann's theoretical framework, this survey explored the meaning of a fall of an institutionalized older adult or fall prevention to rehabilitation registered nurses and whether the experience changed the nurse's practice. Qualitative, descriptive survey. A convenience sample of 742 rehabilitation nurses was asked to describe these experiences and the impact on their practice. Themes discovered related to the meaning of a fall include negative feelings (incongruence) and positive feelings (congruence). Themes related to the meaning of preventing a fall include positive feelings (congruence). Practice change themes emerged from both the experience of a fall and fall prevention. Practice change themes were drawn to Friedemann's (1995) process dimensions. Nurses' experiences and meanings of falls uncovered negative and positive feelings about these falls. New findings of this study were the positive feelings expressed by nurses, when there was no injury or when a fall was prevented. © 2015 Association of Rehabilitation Nurses.

Spheroidization of glass powders for glass ionomer cements.

Science.gov (United States)

Gu, Y W; Yap, A U J; Cheang, P; Kumar, R

2004-08-01

Commercial angular glass powders were spheroidized using both the flame spraying and inductively coupled radio frequency plasma spraying techniques. Spherical powders with different particle size distributions were obtained after spheroidization. The effects of spherical glass powders on the mechanical properties of glass ionomer cements (GICs) were investigated. Results showed that the particle size distribution of the glass powders had a significant influence on the mechanical properties of GICs. Powders with a bimodal particle size distribution ensured a high packing density of glass ionomer cements, giving relatively high mechanical properties of GICs. GICs prepared by flame-spheroidized powders showed low strength values due to the loss of fine particles during flame spraying, leading to a low packing density and few metal ions reacting with polyacrylic acid to form cross-linking. GICs prepared by the nano-sized powders showed low strength because of the low bulk density of the nano-sized powders and hence low powder/liquid ratio of GICs.

Methods for studying the radioactive contamination of plants (1963); Methodes d'etude de la contamination radioactive des vegetaux (1963)

Energy Technology Data Exchange (ETDEWEB)

Coulon, R; Jeanmaire, L; Michon, G [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

1963-07-01

The authors first define the doctrine which led to the devising of a method for studying the radioactive pollution of plants, based on the use of simple techniques, having the possibility of being adapted for routine work, and so devised that each stage is proceeded with only if the preceding one justifies it. For each stage a study is effected comparing the results obtained by the use of more exact techniques. The second part describes in detail the techniques used. (authors) [French] Dans une premiere partie lea auteurs definissent la doctrine qui leur a permis d'elaborer une methode d'etude de la pollution radioactive des vegetaux, basee sur l'utilisation de techniques simples, se pretant au travail de serie et concues de telle maniere que chaque etape n'est abordee que si la precedente le justifie. Chaque etape fait l'objet d'une etude qui compare les resultats a ceux obtenue par des techniques plus precises. La deuxieme partie decrit dans le detail les techniques utilisees. (auteurs)

The development of a very high stability electrostatic generator (1962); Etude et realisation d'un generateur electrostatique a tres haute stabilite (1962)

Energy Technology Data Exchange (ETDEWEB)

Jonckheere, R.E.L. [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

1962-07-01

This thesis deals with the study of an electrostatic high voltage generator having a voltage stability of the order of 10{sup -6} per minute. This equipment should be very useful in electron microscopy. The electrostatic generator is studied as a control system element: transfer function, parasitic signals and noise are determined and a mathematical model is proposed. A theoretical study of the open loop transfer function, stability, transient response, voltage stabilization of five different control systems shows which one should be able to fulfill the requirements There follows a detailed study of drift, a description of the actual system and performance data. (author) [French] Cette etude concerne un generateur electrostatique capable de fournir une tres haute tension continue dont la stabilite relative est de l'ordre de 10{sup -6} pendant une minute. Une telle performance rend cet appareillage tres utile en microscopie electronique. La generatrice electrostatique est etudiee en tant qu'element d'un systeme asservi: on determine successivement la fonction de transfert, les perturbations, le bruit de fond et le modele mathematique. L'etude de cinq differents circuits de regulation en ce qui concerne leur fonction de transfert, stabilite, reponse en regime transitoire, attenuation des perturbations, permettra de choisir le systeme qui semble le mieux repondre aux exigences. Viennent ensuite une etude detaillee de la derive, la description de la realisation pratique et les resultats de mesure. (auteur)

[Risk factors for falls and survival after falling in elderly people in a community].

Science.gov (United States)

Kato, Ryuichi; Takagi, Chika; Sakurai, Naoko; Hoshi, Tanji

2012-05-01

The purpose of this study was to assess the risk factors associated with falls and to examine the effects of falls on survival of elderly people in a community. A questionnaire survey was conducted in 16,462 urban elderly dwellers aged 65 years or more in City A in September 2001. A follow-up survey was carried out in September 2004. We analyzed the data of 8,285 subjects who answered both questionnaires and had not relocated by August 2007. Baseline assessments of health and functioning were carried out in 2001. Falls experienced during the 1-year period before September 2004 were recorded, and the deaths were recorded until August 2007. Statistical analysis was performed using a logistic regression model and Cox's proportional hazards analysis. A total of 6,420 subjects (3,127 men and 3,293 women) who had provided complete answers about their falls were included in the analyses. Of these, 27.8% of women and 16.4% of men had experienced falls, while 6.2% of women and 2.1% of men had experienced falls that caused fractures. We found that the likelihood of fall, with or without fracture development, was greater in women than in men (P falls tended to increase with age in both women and men. Risk factors associated with falls, in addition to age and gender, were pain (odds ratio [OR], 1.75), lack of instrumental activities of daily living (IADL; OR, 1.45), poor self-rated health status (OR, 1.42), and presence of disease (OR, 1.35). Risk factors associated with falls that caused fracture were pain (OR, 1.85) and lack of IADL (OR, 1.61). Cox's proportional hazards analysis showed a significant increase in mortality in both men and women who had experienced falls than in those who had not (hazard ratio [HR], 1.94, 1.43). Aging, pain and disease, lack of IADL, and poor self-rated health status were all significant risk factors for falls in elderly people, and a fall was related to subsequent mortality.

Geriatric fall-related injuries.

Science.gov (United States)

Hefny, Ashraf F; Abbas, Alaa K; Abu-Zidan, Fikri M

2016-06-01

Falls are the leading cause of geriatric injury. We aimed to study the anatomical distribution, severity, and outcome of geriatric fall-related injuries in order to give recommendations regarding their prevention. All injured patients with an age ≥ 60 years who were admitted to Al-Ain Hospital or died in the Emergency Department due to falls were prospectively studied over a four year period. We studied 92 patients. Fifty six of them (60.9%) were females. The mean (standard deviation) of age was 72.2 (9.6) years. Seventy three (89%) of all incidents occurred at home. Eighty three patients (90.2%) fell on the same level. The median (range) ISS was 4 (1-16) and the median GCS (range) was 15 (12-15). The lower limb was the most common injured body region (63%). There were no statistical significant differences between males and females regarding age, ISS, and hospital stay (p = 0.85, p = 0.57, and p = 0.35 respectively). The majority of geriatric fall-related injuries were due to fall from the same level at home. Assessment of risk factors for falls including home hazards is essential for prevention of geriatric fall-related injuries.

Effect of powder geometry on densification

International Nuclear Information System (INIS)

Spasskij, M.R.; Spasskaya, I.A.; Shatalova, I.G.; Shchukin, E.D.

1979-01-01

The effect of particle shape and size composition on the processes of powder vibratory compacting is considered. Using microstress measurements in compacted structures of conglomerated and disintegrated tungsten powders as well as powder strength testing the existence of a zone of transition from a structural deformation to a plastic one has been shown. The formation of phase interparticle contacts of practically stable strength (approximately 5-6 dyn) is a characteristic feature of the zone. The width of the transition zone greatly depends upon geometrical powder properties; 55-65 % for conglomerated tungsten, 63-66 % for integrated tungsten

Fall prevention walker during rehabilitation

Science.gov (United States)

Tee, Kian Sek; E, Chun Zhi; Saim, Hashim; Zakaria, Wan Nurshazwani Wan; Khialdin, Safinaz Binti Mohd; Isa, Hazlita; Awad, M. I.; Soon, Chin Fhong

2017-09-01

This paper proposes on the design of a walker for the prevention of falling among elderlies or patients during rehabilitation whenever they use a walker to assist them. Fall happens due to impaired balance or gait problem. The assistive device is designed by applying stability concept and an accelerometric fall detection system is included. The accelerometric fall detection system acts as an alerting device that acquires body accelerometric data and detect fall. Recorded accelerometric data could be useful for further assessment. Structural strength of the walker was verified via iterations of simulation using finite element analysis, before being fabricated. Experiments were conducted to identify the fall patterns using accelerometric data. The design process and detection of fall pattern demonstrates the design of a walker that could support the user without fail and alerts the helper, thus salvaging the users from injuries due to fall and unattended situation.

Research on Durability of Recycled Ceramic Powder Concrete

Science.gov (United States)

Chen, M. C.; Fang, W.; Xu, K. C.; Xie, L.

2017-06-01

Ceramic was ground into powder with 325 mesh and used to prepare for concrete. Basic mechanical properties, carbonation and chloride ion penetration of the concrete tests were conducted. In addition, 6-hour electric fluxes of recycled ceramic powder concrete were measured under loading. The results showed that the age strength of ceramics powder concrete is higher than that of the ordinary concrete and the fly ash concrete. The ceramic powder used as admixture would reduce the strength of concrete under no consideration of its impact factor; under consideration of the impact factor for ceramic powder as admixture, the carbonation resistance of ceramic powder concrete was significantly improved, and the 28 day carbonation depth of the ceramic powder concrete was only 31.5% of ordinary concrete. The anti-chloride-permeability of recycled ceramic powder concrete was excellent.

Simple process to fabricate nitride alloy powders

International Nuclear Information System (INIS)

Yang, Jae Ho; Kim, Dong-Joo; Kim, Keon Sik; Rhee, Young Woo; Oh, Jang-Soo; Kim, Jong Hun; Koo, Yang Hyun

2013-01-01

Uranium mono-nitride (UN) is considered as a fuel material [1] for accident-tolerant fuel to compensate for the loss of fissile fuel material caused by adopting a thickened cladding such as SiC composites. Uranium nitride powders can be fabricated by a carbothermic reduction of the oxide powders, or the nitriding of metal uranium. Among them, a direct nitriding process of metal is more attractive because it has advantages in the mass production of high-purity powders and the reusing of expensive 15 N 2 gas. However, since metal uranium is usually fabricated in the form of bulk ingots, it has a drawback in the fabrication of fine powders. The Korea Atomic Energy Research Institute (KAERI) has a centrifugal atomisation technique to fabricate uranium and uranium alloy powders. In this study, a simple reaction method was tested to fabricate nitride fuel powders directly from uranium metal alloy powders. Spherical powder and flake of uranium metal alloys were fabricated using a centrifugal atomisation method. The nitride powders were obtained by thermal treating the metal particles under nitrogen containing gas. The phase and morphology evolutions of powders were investigated during the nitriding process. A phase analysis of nitride powders was also part of the present work. KAERI has developed the centrifugal rotating disk atomisation process to fabricate spherical uranium metal alloy powders which are used as advanced fuel materials for research reactors. The rotating disk atomisation system involves the tasks of melting, atomising, and collecting. A nozzle in the bottom of melting crucible introduces melt at the center of a spinning disk. The centrifugal force carries the melt to the edge of the disk and throws the melt off the edge. Size and shape of droplets can be controlled by changing the nozzle size, the disk diameter and disk speed independently or simultaneously. By adjusting the processing parameters of the centrifugal atomiser, a spherical and flake shape

Multimorbidity predicts falls differentially according to the type of fall in postmenopausal women.

Science.gov (United States)

Afrin, Nadia; Honkanen, Risto; Koivumaa-Honkanen, Heli; Lukkala, Pyry; Rikkonen, Toni; Sirola, Joonas; Williams, Lana J; Kröger, Heikki

2016-09-01

To ascertain whether the risk of falls of different types is related to morbidity (number of chronic medical conditions) among postmenopausal women. This cohort study uses data from a population-based prospective cohort study (OSTPRE). The study population consisted of 10,594 women aged 47-56 years living in Kuopio Province, Eastern Finland, in 1989, who responded to postal enquiries at both baseline and 5-year follow-up, in 1994. Morbidity (i.e. number of diagnosed chronic medical conditions) was reported in 1989 and falls in 1994. Falls were categorized as slip or nonslip, and 'frequent falls' was defined as two or more in a 12-month period. The risk (odds ratio (OR) with 95% CI) of a fall increased with the number of chronic medical conditions. The OR was 1.28 (1.17-1.40) for those with 1-2 conditions and 1.41 (1.24-1.60) for those with multimorbidity (≥3 conditions) compared with healthy respondents. Multimorbidity was associated with a greater risk of the woman experiencing frequent nonslip falls (OR=2.57; 2.01-3.29) than frequent slip falls (OR=1.46; 1.17-1.80). Adjusting with logistic regression for age, number of medications and smoking did not affect the risk estimates. Multimorbidity has a much smaller effect on slip than on nonslip falls in postmenopausal women. This should be taken into account when investigating the effects of multimorbidity on fall risk in varying weather conditions. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Falls and fear of falling in vertigo and balance disorders: A controlled cross-sectional study.

Science.gov (United States)

Schlick, Cornelia; Schniepp, Roman; Loidl, Verena; Wuehr, Max; Hesselbarth, Kristin; Jahn, Klaus

2016-01-01

Vertigo and dizziness are among the most prevalent symptoms in neurologic disorders. Although many of these patients suffer from postural instability and gait disturbances, there is only limited data on their risk of falling. We conducted a controlled cross-sectional study at the tertiary care outpatient clinic of the German Center for Vertigo and Balance Disorders using a self-administered questionnaire to assess falls, fall-related injuries, and fear of falling. The recruitment period was 6 months. A total of 569 patients (mean age 59.6 ± 17.1 years, 55% females) and 100 healthy participants were included (response rate > 90%). Dizzy patients with central balance disorders (Parkinsonian, cerebellar, and brainstem oculomotor syndromes) had the highest fall rates (> 50% recurrent fallers, odds ratio > 10). The rate of recurrent fallers was 30% in bilateral vestibular failure and peripheral neuropathy (odds ratio > 5). Patients with functional dizziness (somatoform or phobic vertigo) were concerned about falling but did not fall more often than healthy controls (odds ratio 0.87). Falls are common in patients presenting to a dizziness unit. Those with central syndromes are at risk of recurrent and injurious falling. Fall rates and fear of falling should be assessed in balance disorders and used to guide the regimen of rehabilitation therapy. The identification of risk factors would help provide protective measures to these groups of patients.

MECHANICS OF DYNAMIC POWDER COMPACTION PROCESS

OpenAIRE

Nurettin YAVUZ

1996-01-01

In recent years, interest in dynamic compaction methods of metal powders has increased due to the need to improve compaction properties and to increase production rates of compacts. In this paper, review of dynamic and explosive compaction of metal powders are given. An attempt is made to get a better understanding of the compaction process with the mechanicis of powder compaction.

Risk of falling in a stroke unit after acute stroke: The Fall Study of Gothenburg (FallsGOT).

Science.gov (United States)

Persson, Carina U; Kjellberg, Sigvar; Lernfelt, Bodil; Westerlind, Ellen; Cruce, Malin; Hansson, Per-Olof

2018-03-01

This study aimed to investigate incidence of falls and different baseline variables and their association with falling during hospitalization in a stroke unit among patients with acute stroke. Prospective observational study. A stroke unit at a university hospital. A consecutive sample of stroke patients, out of which 504 were included, while 101 declined participation. The patients were assessed a mean of 1.7 days after admission and 3.8 days after stroke onset. The primary end-point was any fall, from admission to the stroke unit to discharge. Factors associated with falling were analysed using univariable and multivariable Cox hazard regression analyses. Independent variables were related to function, activity and participation, as well as personal and environmental factors. In total, 65 patients (13%) fell at least once. Factors statistically significantly associated with falling in the multivariable analysis were male sex (hazard ratio (HR): 1.88, 95% confidence interval (CI): 1.13-3.14, P = 0.015), use of a walking aid (HR: 2.11, 95% CI: 1.24-3.60, P = 0.006) and postural control as assessed with the modified version of the Postural Assessment Scale for Stroke Patients (SwePASS). No association was found with age, cognition or stroke severity, the HR for low SwePASS scores (⩽24) was 9.33 (95% CI: 2.19-39.78, P = 0.003) and for medium SwePASS scores (25-30) was 6.34 (95% CI: 1.46-27.51, P = 0.014), compared with high SwePASS scores (⩾31). Postural control, male sex and use of a walking aid are associated with falling during hospitalization after acute stroke.

Perceived Fall Risk and Functional Decline: Gender Differences in Patient's Willingness to Discuss Fall Risk, Fall History, or to Have a Home Safety Evaluation.

Science.gov (United States)

Greenberg, Marna Rayl; Moore, Elizabeth C; Nguyen, Michael C; Stello, Brian; Goldberg, Arnold; Barraco, Robert D; Porter, Bernadette G; Kurt, Anita; Dusza, Stephen W; Kane, Bryan G

2016-06-01

The CDC reports that among older adults, falls are the leading cause of injury-related death and rates of fall-related fractures among older women are twice those of men. We set out to 1) determine patient perceptions (analyzed by gender) about their perceived fall risk compared to their actual risk for functional decline and death and 2) to report their comfort level in discussing their fall history or a home safety plan with their provider. Elders who presented to the Emergency Department (ED†) were surveyed. The survey included demographics, the Falls Efficacy Scale (FES) and the Vulnerable Elders Survey (VES); both validated surveys measuring fall concern and functional decline. Females had higher FES scores (mean 12.3, SD 5.9) than males (mean 9.7, SD 5.9 p = .007) in the 146 surveys analyzed. Females were more likely to report an increased fear of falling, and almost three times more likely to have a VES score of 3 or greater than males (OR = 2.86, 95% CI: 1.17-7.00, p = .02). A strong correlation was observed between FES and VES scores (r = 0.80, p fall risk with a provider; there was no difference between genders (p = .57). In this study, irrespective of gender, there appears to be a high association between subjects' perceived fall risk and risk for functional decline and death. The majority of patients are likely willing to discuss their fall risk with their provider. These findings may suggest a meaningful opportunity for fall risk mitigation in this setting.

Contribution to the study of the stability of water-cooled reactors; Contribution a l'etude de la stabilite des reacteurs refroidis par de l'eau

Energy Technology Data Exchange (ETDEWEB)

Coudert, C [Commissariat a l' Energie Atomique, Cadarache (France). Centre d' Etudes Nucleaires

1969-06-01

This work is devoted to the study of the stability of reactors cooled by water subjected only to natural convection. It is made up of two parts, a theoretical study and experimental work, each of these parts being devoted to a consideration of linear and non-linear conditions: - calculation of the transfer function of the reactor using neutronic and hydrodynamic linear equations with the determination of the instability threshold; - demonstration of the existence of the limiting oscillation cycle in the case of a linear feedback using MALKIN'S method; - measurement and interpretation of the reactor's transfer functions and of the hydrodynamic transfer functions; and - analysis of the noise due to boiling. (author) [French] Dans ce travail on etudie la stabilite des piles refroidies par de l'eau circulant en convection naturelle. Cette etude se divise en deux parties: un travail theorique et un travail experimental, chacune de ces parties comportant une etude lineaire et une etude non-lineaire: - calcul de la fonction de transfert du reacteur a partir des equations lineaires de la neutronique et de l'hydrodynamique avec determination du seuil d'instabilite; - demonstration de l'existence du cycle limite des oscillations dans le cas d'une retroaction lineaire en utilisant la methode de MALKIN; - mesure et interpretation de la fonction de transfert du reacteur et des fonctions de transfert hydrodynamiques; et - analyse du bruit d'ebullition. (auteur)

Fear of Falling in Women with Fibromyalgia and Its Relation with Number of Falls and Balance Performance.

Science.gov (United States)

Collado-Mateo, D; Gallego-Diaz, J M; Adsuar, J C; Domínguez-Muñoz, F J; Olivares, P R; Gusi, N

2015-01-01

To evaluate fear of falling, number of falls, and balance performance in women with FM and to examine the relationship between these variables and others, such as balance performance, quality of life, age, pain, and impact of fibromyalgia. A total of 240 women participated in this cross-sectional study. Of these, 125 had fibromyalgia. Several variables were assessed: age, fear of falling from 0 to 100, number of falls, body composition, balance performance, lower limb strength, health-related quality of life, and impact of fibromyalgia. Women with fibromyalgia reported more falls and more fear of falling. Fear of falling was associated with number of falls in the last year, stiffness, perceived balance problems, impact of FM, and HRQoL whereas the number of falls was related to fear of falling, balance performance with eyes closed, pain, tenderness to touch level, anxiety, self-reported balance problems, impact of FM, and HRQoL. FM has an impact on fear of falling, balance performance, and number of falls. Perceived balance problems seem to be more closely associated with fear of falling than objective balance performance.

Falls in older people

NARCIS (Netherlands)

van Dieën, Jaap H.; Pijnappels, Mirjam

Falls are common incidents, which can have major con-sequences. For example, falls and the interrelated category of accidents being struck by or against objects account for more than 40% of injuries and 30% of injury costs in the USA (Corso et al., 2006). Especially among older adults, falls occur

Tantalum powder consolidation, modeling and properties

International Nuclear Information System (INIS)

Bingert, S.R.; Vargas, V.D.; Sheinberg, H.C.

1996-01-01

A systematic approach was taken to investigate the consolidation of tantalum powders. The effects of sinter time, temperature and ramp rate; hot isostatic pressing (HIP) temperature and time; and powder oxygen content on consolidation density, kinetics, microstructure, crystallographic texture, and mechanical properties have been evaluated. In general, higher temperatures and longer hold times resulted in higher density compacts with larger grain sizes for both sintering and HIP'ing. HIP'ed compacts were consistently higher in density than sintered products. The higher oxygen content powders resulted in finer grained, higher density HIP'ed products than the low oxygen powders. Texture analysis showed that the isostatically processed powder products demonstrated a near random texture. This resulted in isotropic properties in the final product. Mechanical testing results showed that the HIP'ed powder products had consistently higher flow stresses than conventionally produced plates, and the sintered compacts were comparable to the plate material. A micromechanics model (Ashby HIP model) has been employed to predict the mechanisms active in the consolidation processes of cold isostatic pressing (CIP), HIP and sintering. This model also predicts the density of the end product and whether grain growth should be expected under the applied processing conditions

Vacuum hot pressing of titanium-alloy powders

International Nuclear Information System (INIS)

Malik, R.K.

1975-01-01

Full or nearly full dense products of wrought-metal properties have been obtained by vacuum hot pressing (VHP) of several prealloyed Ti--6Al--4V powders including hydride, hydride/dehydride, and rotating electrode process (REP) spherical powder. The properties of billets VHP from Ti--6Al--4V hydride powder and from hydride/dehydride powders have been shown to be equivalent. The REP spherical powder billets processed by VHP or by hot isostatic pressing (HIP) resulted in equivalent tensile properties. The potential of VHP for fabrication of near net aircraft parts such as complex fittings and engine disks offers considerable cost savings due to reduced material and machining requirements

Aerodynamic and thermal studies of cans of gas cooled fuel elements; Etudes aerodynamiques et thermiques de gaines d'elements combustibles refroidis par gaz

Energy Technology Data Exchange (ETDEWEB)

Gelin, P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires; Milliat, J P [Electricite de France (EDF), 75 - Paris (France)

1964-07-01

Research on clusters was undertaken at the CEA in 1959, while studies on herring-bone cans were developed at the EDF Laboratory at Chatou and the CEA laboratory at Saclay at the end of 1959. In 1962, a general study on corrugations was begun at the Saclay Laboratory with a view to improving the clusters, and continued later in both laboratories relative to the internal cooling of annular fuel elements. As these studies progressed, trial facilities were extended while experimental methods have improved constantly. At the present time, both laboratories, working in complete collaboration, have powerful means at their disposal. Work on the clusters has been concerned chiefly with pressure losses due to the assembly parts, and with the temperature variations around the elements of the cluster. In this way, we have been able to determine satisfactorily the hot points of the can, the deformations of the rods and the conditions of stability of these deformations. In the case of the herring-bone cans, studies have been directed to the evolution of performances as a function of the geometric parameters on the one hand, and to the special aerodynamic and thermal features caused by the fins and by interruptions of cartridge on the other hand. These studies have led to a very thorough knowledge of the cartridges chosen for the reactors EDF 2 and EDF 3, and now open up very hopeful prospects for future reactors, particularly those fitted with annular elements; among the alternatives suitable for the inner surface of the annular element can, corrugations and longitudinal fins have been fairly extensively tested over a wide range of Reynolds number. (authors) [French] Les etudes de grappes ont ete entreprises au C.E.A. en 1959, tandis que les etudes de gaines a chevrons se sont developpees au Laboratoire de Chatou de l'EDF et au Laboratoire de Saclay du C.E.A. a la fin de l'annee 1959. En 1962, une etude generale sur les corrugations a ete commencee au Laboratoire de Saclay pour

[Fear of falling in a fall clinic for geriatric patients: a pilot study

NARCIS (Netherlands)

Dautzenberg, P.LJ.; Buurman, B.H.; Loonen, A.J.; Wouters, C.J.; Olde Rikkert, M.G.M.

2005-01-01

OBJECTIVE: In this pilot study we want to determine how often fear of falling occurs in geriatric patients visiting a fall clinic and to study the characteristics of fear of falling and its consequences. DESIGN: Retrospective study of patient's records. METHOD: A random sample of 100 medical records

Issues in Geriatric Care: Falls.

Science.gov (United States)

Patel, Dipesh; Ackermann, Richard J

2018-05-01

One in three older adults falls each year. There are approximately 2.5 million falls among older adults treated in emergency departments. Falls account for 87% of all fractures in this age group. The biggest risk factor for falling is a history of falls. Other risk factors include frailty, sedative and anticholinergic drugs, polypharmacy, and a variety of medical conditions. Current recommendations are that all patients age 65 years and older should be asked about falls each year. Patients also can be screened for fall risk with a variety of approaches including questionnaires and the Timed Up & Go test. For patients who have fallen or are at risk, care should focus on correcting reversible home environmental factors that predispose to falls, minimizing the use of drugs with sedating properties, addressing vision conditions, recommending physical exercise (including balance, strength, and gait training), and managing postural hypotension as well as foot conditions and footwear. In addition, vitamin D and calcium supplementation should be considered. For patients needing anticoagulation for medical reasons, an assessment must balance fall risk (and thus bleeding from a fall) versus the risk of discontinuing anticoagulation (eg, sustaining an embolic stroke from atrial fibrillation). Written permission from the American Academy of Family Physicians is required for reproduction of this material in whole or in part in any form or medium.

Superconductors by powder metallurgy techniques

International Nuclear Information System (INIS)

Pickus, M.R.; Wang, J.L.F.

1976-05-01

Fabrication methods for Nb 3 Sn type compounds are described. Information is included on the Bell Telephone process, the General Electric tape process, superconductor stability, the bronze process, powder metallurgy multifilamentary tapes and wires, and current assessment of powder metallurgy superconducting wire

Falls self-efficacy and falls incidence in community-dwelling older people: the mediating role of coping.

Science.gov (United States)

Loft, Christine C; Jones, Fergal W; Kneebone, Ian I

2017-11-08

A cognitive behavioral model predicts that coping responses mediate the relationship between falls related psychological concerns and falls incidence, in community-dwelling older people. If empirical support could be found for this pathway then interventions could be developed to reduce falls risk by targeting coping strategies. Therefore, this study aimed to begin the process of testing whether coping responses mediate the association between falls self-efficacy (a principal element of falls related psychological concerns) and falls incidence, in community-dwelling older people. In a cross-sectional design, 160 community-dwelling older people (31 male, 129 female; mean age 83.47 years) completed the Falls Efficacy Scale-International, the Revised-Ways of Coping Questionnaire, the Turning to Religion subscale of the COPE, and a falls questionnaire. Data were analyzed via mediation analysis using a bootstrapping approach. Lower falls self-efficacy was associated with higher falls incidence, and more self-controlling coping was found to be a partial mediator of this association, with a confidence interval for the indirect effect of (0.003, 0.021) and an effect size of κ 2 = 0.035. The association was not mediated by the other measured coping responses; namely, turning to religion, distancing, seeking social support, accepting responsibility, escape-avoidance, planful problem-solving, and positive reappraisal. Self-controlling coping may mediate the association between falls self-efficacy and falling. If longitudinal studies confirm this finding then coping could be targeted in interventions to reduce falls.

Fear of Falling in Women with Fibromyalgia and Its Relation with Number of Falls and Balance Performance

Directory of Open Access Journals (Sweden)

D. Collado-Mateo

2015-01-01

Full Text Available Objective. To evaluate fear of falling, number of falls, and balance performance in women with FM and to examine the relationship between these variables and others, such as balance performance, quality of life, age, pain, and impact of fibromyalgia. Methods. A total of 240 women participated in this cross-sectional study. Of these, 125 had fibromyalgia. Several variables were assessed: age, fear of falling from 0 to 100, number of falls, body composition, balance performance, lower limb strength, health-related quality of life, and impact of fibromyalgia. Results. Women with fibromyalgia reported more falls and more fear of falling. Fear of falling was associated with number of falls in the last year, stiffness, perceived balance problems, impact of FM, and HRQoL whereas the number of falls was related to fear of falling, balance performance with eyes closed, pain, tenderness to touch level, anxiety, self-reported balance problems, impact of FM, and HRQoL. Conclusion. FM has an impact on fear of falling, balance performance, and number of falls. Perceived balance problems seem to be more closely associated with fear of falling than objective balance performance.

Fall risk assessment: retrospective analysis of Morse Fall Scale scores in Portuguese hospitalized adult patients.

Science.gov (United States)

Sardo, Pedro Miguel Garcez; Simões, Cláudia Sofia Oliveira; Alvarelhão, José Joaquim Marques; Simões, João Filipe Fernandes Lindo; Melo, Elsa Maria de Oliveira Pinheiro de

2016-08-01

The Morse Fall Scale is used in several care settings for fall risk assessment and supports the implementation of preventive nursing interventions. Our work aims to analyze the Morse Fall Scale scores of Portuguese hospitalized adult patients in association with their characteristics, diagnoses and length of stay. Retrospective cohort analysis of Morse Fall Scale scores of 8356 patients hospitalized during 2012. Data were associated to age, gender, type of admission, specialty units, length of stay, patient discharge, and ICD-9 diagnosis. Elderly patients, female, with emergency service admission, at medical units and/or with longer length of stays were more frequently included in the risk group for falls. ICD-9 diagnosis may also be an important risk factor. More than a half of hospitalized patients had "medium" to "high" risk of falling during the length of stay, which determines the implementation and maintenance of protocoled preventive nursing interventions throughout hospitalization. There are several fall risk factors not assessed by Morse Fall Scale. There were no statistical differences in Morse Fall Scale score between the first and the last assessment. Copyright © 2015 Elsevier Inc. All rights reserved.

Pro-Active Fall-Risk Management is Mandatory to Sustain in Hospital-Fall Prevention in Older Patients--Validation of the LUCAS Fall-Risk Screening in 2,337 Patients.

Science.gov (United States)

Hoffmann, V S; Neumann, L; Golgert, S; von Renteln-Kruse, W

2015-12-01

Prevention of in-hospital falls contributes to improvement of patient safety. However, the identification of high-risk patients remains a challenge despite knowledge of fall-risk factors. Hence, objective was to prospectively validate the performance of the LUCAS (Longitudinal Urban Cohort Ageing Study) fall-risk screening, based on routine data (fall history, mobility, mental status) and applied by nurses. Observational study comparing two groups of patients who underwent different fall-risk screenings; the LUCAS screening (2010 - 2011) and the STRATIFY (St. Thomas's Risk Assessment Tool In Falling Elderly Inpatients) (2004 - 2006). Urban teaching hospital. Consecutively hospitalized patients (≥ 65 years old) were screened on admission; LUCAS n = 2,337, STRATIFY n = 4,735. The proportions of fallers were compared between the STRATIFY and the LUCAS time periods. The number of fallers expected was compared to that observed in the LUCAS time period. Standardized fall-incidence recording included case-note checks for unreported falls. Plausibility checks of fall-risk factors and logistic regression analysis for variable fall-risk factors were performed. The proportions of fallers during the two time periods were LUCAS n = 291/2,337 (12.5%) vs. STRATIFY n = 508/4,735 (10.7%). After adjustment for risk-factor prevalence, the proportion of fallers expected was 14.5% (334/2,337), the proportion observed was 12.5% (291/2,337) (p = 0.038). In-hospital fall prevention including systematic use of the LUCAS fall-risk screening reduced the proportion of fallers compared to that expected from the patients' fall-risk profile. Raw proportions of fallers are not suitable to evaluate fall prevention in hospital because of variable prevalence of patients' fall-risk factors over time. Continuous communication, education and training is needed to sustain in-hospital falls prevention.

History of falls, gait, balance, and fall risks in older cancer survivors living in the community.

Science.gov (United States)

Huang, Min H; Shilling, Tracy; Miller, Kara A; Smith, Kristin; LaVictoire, Kayle

2015-01-01

Older cancer survivors may be predisposed to falls because cancer-related sequelae affect virtually all body systems. The use of a history of falls, gait speed, and balance tests to assess fall risks remains to be investigated in this population. This study examined the relationship of previous falls, gait, and balance with falls in community-dwelling older cancer survivors. At the baseline, demographics, health information, and the history of falls in the past year were obtained through interviewing. Participants performed tests including gait speed, Balance Evaluation Systems Test, and short-version of Activities-specific Balance Confidence scale. Falls were tracked by mailing of monthly reports for 6 months. A "faller" was a person with ≥1 fall during follow-up. Univariate analyses, including independent sample t-tests and Fisher's exact tests, compared baseline demographics, gait speed, and balance between fallers and non-fallers. For univariate analyses, Bonferroni correction was applied for multiple comparisons. Baseline variables with Pfalls with age as covariate. Sensitivity and specificity of each predictor of falls in the model were calculated. Significance level for the regression analysis was Pfalls. Baseline demographics, health information, history of falls, gaits speed, and balance tests did not differ significantly between fallers and non-fallers. Forward logistic regression revealed that a history of falls was a significant predictor of falls in the final model (odds ratio =6.81; 95% confidence interval =1.594-29.074) (Pfalls were 74% and 69%, respectively. Current findings suggested that for community-dwelling older cancer survivors with mixed diagnoses, asking about the history of falls may help detect individuals at risk of falling.

Impact strength of sintered astaloy CrM powders

International Nuclear Information System (INIS)

Kazior, J.; Ploszczak, J.; Nykiel, M.; Pieczonka, T.

2003-01-01

In this paper results of a series of impact tests on sintered Astaloy CrM powders alloys modified by boron are presented and discussed. Boron in different forms, i.e. as elemental boron powder, boron carbide B 4 C powder or mixture of boron and carbon elemental powders, was used in different weight percentage to activate sintering of Astaloy CrM powder and to increase hardenability, with aim of increasing impact strength in view of structural applications. (author)

Epidemiology of falls in older age.

Science.gov (United States)

Peel, Nancye May

2011-03-01

Worldwide, falls among older people are a public health concern because of their frequency and adverse consequences in terms of morbidity, mortality, and quality of life, as well as their impact on health system services and costs. This epidemiological review outlines the public health burden of falls and fall-related injuries and the impact of population aging. The magnitude of the problem is described in terms of the classification of falls and measurement of outcomes, including fall incidence rates across settings, sociodemographic determinants, international trends, and costs of falls and fall-related injuries. Finally, public health approaches to minimize falls risk and consequent demand on health care resources are suggested.

Shock compaction of molybdenum powder

Science.gov (United States)

Ahrens, T. J.; Kostka, D.; Vreeland, T., Jr.; Schwarz, R. B.; Kasiraj, P.

1983-01-01

Shock recovery experiments which were carried out in the 9 to 12 GPa range on 1.4 distension Mo and appear adequate to compact to full density ( 45 (SIGMA)m) powders were examined. The stress levels, however, are below those calculated to be from 100 to approx. 22 GPa which a frictional heating model predicts are required to consolidate approx. 10 to 50 (SIGMA)m particles. The model predicts that powders that have a distension of m=1.6 shock pressures of 14 to 72 GPa are required to consolidate Mo powders in the 50 to 10 (SIGMA)m range.

Impact of fear of falling and fall history on disability incidence among older adults: Prospective cohort study.

Science.gov (United States)

Makino, Keitaro; Makizako, Hyuma; Doi, Takehiko; Tsutsumimoto, Kota; Hotta, Ryo; Nakakubo, Sho; Suzuki, Takao; Shimada, Hiroyuki

2018-04-01

Fear of falling (FOF) is a major health problem for older adults, present not just in fallers, but also nonfallers. This study examined the impact of FOF and fall history on disability incidence among community-dwelling older adults from a prospective cohort study. A total of 5104 older adults living in community settings participated in baseline assessment and were followed up for about 4 years (median 52 mo, range 49-55 mo). At baseline, participants were assessed the presence of FOF and their fall history, and divided into 4 groups: Fall (-) FOF (-), Fall (+) FOF (-), Fall (-) FOF (+), and Fall (+) FOF (+). Disability incidence was defined as national long-term care insurance certification for personal support or care. During the follow-up period, 429 participants (9.9%) were newly certified as having a disability and needing personal support for long-term care insurance. Fall (-) FOF (+) group and Fall (+) FOF (+) group showed a significantly higher risk of disability incidence than Fall (-) FOF (-) group even after adjusting for covariates (Fall (-) FOF (+): hazard ratio 1.28, 95% confidence interval, 1.01-1.62, Fall (+) FOF (+): hazard ratio 1.44, 95% confidence interval, 1.05-1.98). Fear of falling could be a simple and useful predictor of disability incidence in community-dwelling older adults. Identifying and decreasing fall risk factors may prevent fall-related injuries, but excessive FOF may be associated with increased risk of disability incidence. Copyright © 2017 John Wiley & Sons, Ltd.

Fall Prevention Hits Stumbling Blocks.

Science.gov (United States)

Huff, Charlotte

2018-03-01

Implementation of efforts to screen older people for fall risk-and to intervene before falls occur-have been scattershot at best. Ongoing studies of fall prevention called STRIDE (Strategies to Reduce Injuries and Develop Confidence in Elders) might change that. The studies look at whether clinicians can implement a fall-prevention program across rural, urban, and suburban treatment settings.

Risk factors for falls and fall-related injuries in adults 85 years of age and older.

Science.gov (United States)

Grundstrom, Anna C; Guse, Clare E; Layde, Peter M

2012-01-01

Falls are a leading cause of morbidity and mortality in older adults. No previous studies on risk factors for falls have focused on adults 85 years and older, the most rapidly growing segment of adults. We examined demographic, health, and behavioral risk factors for falls and fall-related injuries in adults 65 years and older, with a particular focus on adults 85 years and older. We analyzed self-reported information from the Behavioral Risk Factor Surveillance System (BRFSS) for 2008. Data was available for 120,923 people aged 65 or older and 12,684 people aged 85 or older. Of those aged 85 or older, 21.3% reported at least one fall in the past 3 months and 7.2% reported at least one fall related injury requiring medical care or limiting activity for a day or longer. Below average general health, male sex, perceived insufficient sleep, health problems requiring assistive devices, alcohol consumption, increasing body mass index and history of stroke were all independently associated with a greater risk of falls or fall related injuries. The greater risk of falling in those 85 years and older appeared to be due to the deterioration of overall health status with age; among those with excellent overall health status, there was no greater risk of falling in adults 85 years and older compared to those 65-84 years of age. Our results suggest that those with risk factors for falls and fall-related injuries may be appropriate targets for evidence-based fall prevention programs. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

[Impact of fall risk and fear of falling on mobility of independently living senior citizens transitioning to frailty: screening results concerning fall prevention in the community].

Science.gov (United States)

Anders, J; Dapp, U; Laub, S; von Renteln-Kruse, W

2007-08-01

There is a strong relation between mobility, walking safety and living independently in old age. People with walking problems suffer from fear of falling and tend to restrict their mobility and performance level in the community environment--even before falls occur. This study was planned to test the validity and prognostic value of a fall risk screening instrument ("Sturz-Risiko-Check") that has already shown its feasibility, acceptance and reliability, targeting independently living senior citizens. The study sample was recruited from a sheltered housing complex in Hamburg (with written consent). Persons with need of professional care ("Pflegestufe" in Germany) were excluded. The residents were asked to fill in the multidimensional questionnaire ("Sturz-Risiko- Check"). In a second step, a trained nurse asked the participants in a phone call about their competence in the instrumental activities of daily living (I-ADL mod. from Lawton, Brody 1969) and about their usual mobility performance level (e.g. frequency and distance of daily walks, use of public transport). According to the number and weight of self-reported risk factors for falling, three groups: "low fall risk", "medium fall risk" and "high fall risk" were classified. Finally, this classification was re-tested after one year, asking for falls and fall related injuries. A total of 112 senior citizens without need of personal care, living in a sheltered housing facility were asked to participate. Acceptance was high (76.1%). Self-reported data from 79 participants concerning falls, fall-risk, mobility and instrumental activities of daily living were included in the statistical analyses. Mean age was 78 (64 to 93) years and associated by a high percentage of women (75.9%) in this sample. The older participants reported 0 to 13 different factors (mean 5) related to a high risk of future falls. Most participants (78.5%) quit cycling because of fear of falling. There was a high incidence in the study sample

Metal powder production by gas atomization

Science.gov (United States)

Ting, E. Y.; Grant, N. J.

1986-01-01

The confined liquid, gas-atomization process was investigated. Results from a two-dimensional water model showed the importance of atomization pressure, as well as delivery tube and atomizer design. The atomization process at the tip of the delivery tube was photographed. Results from the atomization of a modified 7075 aluminum alloy yielded up to 60 wt pct. powders that were finer than 45 microns in diameter. Two different atomizer designs were evaluated. The amount of fine powders produced was correlated to a calculated gas-power term. An optimal gas-power value existed for maximized fine powder production. Atomization at gas-power greater than or less than this optimal value produced coarser powders.

What are the Main Physical Functioning Factors Associated With Falls Among Older People With Different Perceived Fall Risk?

Science.gov (United States)

Moreira, Mirian N; Bilton, Tereza L; Dias, Rosangela C; Ferriolli, Eduardo; Perracini, Monica R

2017-07-01

Fall risk perceptions may influence the judgement over physical and functional competencies to avoid falls. However, few studies have explored the physical functioning characteristics associated with falls among older people with low perceived fall risk. This study aimed to identify the prevalence of falls and physical functioning factors associated with falling among community-dwelling older adults with low and high perceived fall risk. We conducted a cross-sectional population based study with 773 community-dwelling elders. Perceived fall risk was investigated using Falls Efficacy Scale International. We considered fallers those who reported at least one fall in the previous 12 months. Physical functioning measures used were grip strength, usual gait speed, sit-to-stand test, five step test, timed up and go test, one-legged stance test, anterior and lateral functional reach test. At least one fall was reported by 103 (30%) participants with low perceived fall risk and by 196 (46%) participants with high perceived fall risk. The odds of falling were lower among those with greater grip strength and with a greater stance time in one-legged test, and the odds of falling among elders with high perceived fall risk were higher among those who took more time in performing the five step test. We believe that our results highlight the need of not neglecting the risk of falls among active older adults with low perceived fall risk, particularly in those elders that show reduced stability in a small base of support and a lower leg strength. In addition, we suggest that elders with high perceived fall risk should be assessed using anticipatory postural adjustment tests. Particularly, our results may help physiotherapists to identify eligible elders with different perceptions of fall risk for tailored interventions aimed at reducing falls. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Hygroscopic behavior of lyophilized acerola pulp powder

Directory of Open Access Journals (Sweden)

Luciana C. Ribeiro

2016-03-01

Full Text Available ABSTRACT Powder products are characterized by their practicality and long life. However, fruit powders have high hygroscopicity and tend to agglomerate due to its hydrophilic nature. The isotherms of equilibrium moisture content apply to the study of dehydrated food preservation potential. Acerola is a nutritionally rich fruit, with great economic and industrial potential. The objective of this study was to analyse acerola powder adsorption isotherms obtained by lyophilization and characterize the powder obtained from lyophilized acerola pulp. Analysis of hygroscopicity, solubility and degree of caking were performed. Isotherms were represented by the mathematical models of GAB, BET, Henderson and Oswin, at temperatures of 25, 35 and 45 °C. According to the results, the obtained powder showed hygroscopicity of 5.96 g of absorbed water 100g-1 of solids, solubility of 95.08% and caking of 14.12%. The BET model showed the best fit to the adsorption isotherms of the acerola pulp powder obtained by lyophilization. The obtained isotherm was of type III, with a "J" shape. There was an inversion of the effect of temperature on the isotherms of acerola powders.

Assessment of muscle mass, risk of falls and fear of falling in elderly people with diabetic neuropathy

Directory of Open Access Journals (Sweden)

Hudson Azevedo Pinheiro

Full Text Available Abstract Objective : To assess muscle mass, risk of falls and fear of falling in elderly adults with diabetic neuropathy (DNP. Methods : 50 elderly patients with diabetes mellitus (DM and diabetic neuropathy (NPD participated in this study. Risk of falling was assessed using the Berg Balance Scale (BBS. Fear of falling was assessed by means of the Falls Efficacy Scale-International (FES-I. Muscle mass was assessed by tetrapolar bioimpedance analysis (BIA and Janssen's equation. Subjects were divided into two groups: one with a history of falls in the six months before study enrollment (G1 and the other without history of falls (G2. Results : There were statistically significant differences between G1 and G2 regarding lean body mass (p < 0.05, risk of falls as measured by the BBS (p < 0.01, and fear of falling as measured by the FES-I (p < 0.01. In addition, there was a significant correlation between the BBS and BIA (r = 0.45 and p < 0.01, showing that the greater the lean body mass, the lower the risk of falling. Conclusions : We found an association between lean mass, risk of falls and fear of falling in elderly adults with DNP and a history of falls from own height.

New methods for fall risk prediction.

Science.gov (United States)

Ejupi, Andreas; Lord, Stephen R; Delbaere, Kim

2014-09-01

Accidental falls are the leading cause of injury-related death and hospitalization in old age, with over one-third of the older adults experiencing at least one fall or more each year. Because of limited healthcare resources, regular objective fall risk assessments are not possible in the community on a large scale. New methods for fall prediction are necessary to identify and monitor those older people at high risk of falling who would benefit from participating in falls prevention programmes. Technological advances have enabled less expensive ways to quantify physical fall risk in clinical practice and in the homes of older people. Recently, several studies have demonstrated that sensor-based fall risk assessments of postural sway, functional mobility, stepping and walking can discriminate between fallers and nonfallers. Recent research has used low-cost, portable and objective measuring instruments to assess fall risk in older people. Future use of these technologies holds promise for assessing fall risk accurately in an unobtrusive manner in clinical and daily life settings.

Metallography of powder metallurgy materials

International Nuclear Information System (INIS)

Lawley, Alan; Murphy, Thomas F.

2003-01-01

The primary distinction between the microstructure of an ingot metallurgy/wrought material and one fabricated by the powder metallurgy route of pressing followed by sintering is the presence of porosity in the latter. In its various morphologies, porosity affects the mechanical, physical, chemical, electrical and thermal properties of the material. Thus, it is important to be able to characterize quantitatively the microstructure of powder metallurgy parts and components. Metallographic procedures necessary for the reliable characterization of microstructures in powder metallurgy materials are reviewed, with emphasis on the intrinsic challenges presented by the presence of porosity. To illustrate the utility of these techniques, five case studies are presented involving powder metallurgy materials. These case studies demonstrate problem solving via metallography in diverse situations: failure of a tungsten carbide-coated precipitation hardening stainless steel, failure of a steel pump gear, quantification of the degree of sinter (DOS), simulation of performance of a porous filter using automated image analysis, and analysis of failure in a sinter brazed part assembly

A study of the aptitude of soils under natural conditions to retain radiostrontium; Etude de la vocation des sols en place a la retention du radiostrontium

Energy Technology Data Exchange (ETDEWEB)

Bovard, P; Grauby, A [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

1960-07-01

Independently of the theoretical study of the propagation of radioactivity in the soil as a result of submersions or of radioactive rain, the authors have studied directly and practically how this radioactivity can vary in the actual soil. To this end a simple, rapid method has been perfected; it makes it possible to maintain for each soil sample the natural parameters (structure, humidity, etc.) without introducing boundary effects. In the laboratory, after charging the soil samples, part of the study of the propagation of radioactivity is done by autoradiography; finally, as a practical application, the study of an atomic site illustrates the methods described. (author) [French] Independamment de l'etude theorique de la propagation de la radioactivite dans le sol a la suite de submersions ou de pluies radioactives, les auteurs ont etudie directement et pratiquement comment pourrait evoluer cette radioactivite dans les sols en place. Pour cela, une methode simple et rapide a ete mise au point; elle permet de conserver pour chaque echantillon de sol, les parametres naturels (structure, humidite, etc...), sans introduire d'effets de paroi. En laboratoire, apres mise en charge des massifs preleves, une partie de l'etude de la propagation des radioelements est realisee par autoradiographie; enfin, une application pratique, l'etude d'un site atomique, illustre l'expose. (auteur)

A study of the aptitude of soils under natural conditions to retain radiostrontium; Etude de la vocation des sols en place a la retention du radiostrontium

Energy Technology Data Exchange (ETDEWEB)

Bovard, P.; Grauby, A. [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

1960-07-01

Independently of the theoretical study of the propagation of radioactivity in the soil as a result of submersions or of radioactive rain, the authors have studied directly and practically how this radioactivity can vary in the actual soil. To this end a simple, rapid method has been perfected; it makes it possible to maintain for each soil sample the natural parameters (structure, humidity, etc.) without introducing boundary effects. In the laboratory, after charging the soil samples, part of the study of the propagation of radioactivity is done by autoradiography; finally, as a practical application, the study of an atomic site illustrates the methods described. (author) [French] Independamment de l'etude theorique de la propagation de la radioactivite dans le sol a la suite de submersions ou de pluies radioactives, les auteurs ont etudie directement et pratiquement comment pourrait evoluer cette radioactivite dans les sols en place. Pour cela, une methode simple et rapide a ete mise au point; elle permet de conserver pour chaque echantillon de sol, les parametres naturels (structure, humidite, etc...), sans introduire d'effets de paroi. En laboratoire, apres mise en charge des massifs preleves, une partie de l'etude de la propagation des radioelements est realisee par autoradiographie; enfin, une application pratique, l'etude d'un site atomique, illustre l'expose. (auteur)

First Aid: Falls

Science.gov (United States)

... Folleto de instructiones: Caídas (Falls) With all the running, climbing, and exploring kids do, it's no surprise that falls are common. Although many result in mild bumps, cuts, and bruises, some can cause serious injuries that need immediate medical attention. What to Do ...

Spheroidization of molybdenum powder by radio frequency thermal plasma

Science.gov (United States)

Liu, Xiao-ping; Wang, Kuai-she; Hu, Ping; Chen, Qiang; Volinsky, Alex A.

2015-11-01

To control the morphology and particle size of dense spherical molybdenum powder prepared by radio frequency (RF) plasma from irregular molybdenum powder as a precursor, plasma process parameters were optimized in this paper. The effects of the carrier gas flow rate and molybdenum powder feeding rate on the shape and size of the final products were studied. The molybdenum powder morphology was examined using high-resolution scanning electron microscopy. The powder phases were analyzed by X-ray diffraction. The tap density and apparent density of the molybdenum powder were investigated using a Hall flow meter and a Scott volumeter. The optimal process parameters for the spherical molybdenum powder preparation are 50 g/min powder feeding rate and 0.6 m3/h carrier gas rate. In addition, pure spherical molybdenum powder can be obtained from irregular powder, and the tap density is enhanced after plasma processing. The average size is reduced from 72 to 62 µm, and the tap density is increased from 2.7 to 6.2 g/cm3. Therefore, RF plasma is a promising method for the preparation of high-density and high-purity spherical powders.

In-house characterization of protein powder

DEFF Research Database (Denmark)

Hartmann, Christian Grundahl; Nielsen, Ole Faurskov; Ståhl, Kenny

2010-01-01

X-ray powder diffraction patterns of lysozyme and insulin were recorded on a standard in-house powder diffractometer. The experimental powder diffraction patterns were compared with patterns calculated from Protein Data Bank coordinate data. Good agreement was obtained by including straightforward...... to include calculated H-atom positions did not improve the overall fit and was abandoned. The method devised was shown to be a quick and convenient tool for distinguishing precipitates and polymorphs of proteins....

Powder handling for automated fuel processing

International Nuclear Information System (INIS)

Frederickson, J.R.; Eschenbaum, R.C.; Goldmann, L.H.

1989-01-01

Installation of the Secure Automated Fabrication (SAF) line has been completed. It is located in the Fuel Cycle Plant (FCP) at the Department of Energy's (DOE) Hanford site near Richland, Washington. The SAF line was designed to fabricate advanced reactor fuel pellets and assemble fuel pins by automated, remote operation. This paper describes powder handling equipment and techniques utilized for automated powder processing and powder conditioning systems in this line. 9 figs

Study of the dynamic behaviour of the reactor Rapsodie; Etude du comportement dynamique de la pile rapsodie

Energy Technology Data Exchange (ETDEWEB)

Abdon, R; Chaigne, M [Commissariat a l' Energie Atomique, Cadarache (France). Centre d' Etudes Nucleaires

1964-07-01

. The investigation of the control, carried out on analog computer, served to determine the different possible means of starting and changing the conditions of the reactor as well as its automatic control. The calculations were examined in the totality by the construction of a training simulator composed of a board similar to the control board of the reactor, all of whose commands (reactivity and flows) work on an analogue computer which resolves in the real time the dynamic equations of the reactor and which reproduces simultaneously all the parameters representing the state of the installation (power, period, temperatures, etc. ) in the case of various incidents as well as under normal conditions of functioning. (authors) [French] On sait que le developpement des reacteurs surgenerateurs a neutrons rapides pose des problemes nouveaux d'une part dans les domaines mecanique et thermique et d'autre part en ce qui concerne leur comportement dynamique et leur surete. La pile RAPSODIE a ete l'objet de tres nombreuses etudes dynamiques effectuees sur machines analogiques et digitales, pour deux versions du combustible (metal et oxyde). Apres elaboration des modeles mathematiques representatifs de l'ensemble de l'installation (bloc pile et circuit de refroidissement) tant du point de vue neutronique que du point de vue thermodynamique, on a mis au point les schemas analogiques et les codes digitaux utilisables pour mener a bien les simulations d'incidents, de conduite et de stabilite du reacteur. On s'est attache, par rapport aux methodes habituelles a obtenir une precision plus grande, par un decoupage en zones plus fines, par l'emploi de formulations plus representatives du systeme reel, voire solubles analytiquement. Les etudes d'incidents ont ete effectuees par voie analogique pour l'ensemble de l'installation et par voie digitale pour l'etude du bloc pile seul ou de l'installation fonctionnant avec un seul circuit thermique. Un programme complementaire special - qui, a

Development of granular powder manufacturing technology by spray pyrolysis

International Nuclear Information System (INIS)

Katoh, Yoshiyuki; Kawase, Keiichi; Takahashi, Yoshiharu; Todokoro, Akio

1996-01-01

For shortening of mixed-oxide (MOX) fuel manufacturing process and improvement in treatment of MOX-powder, we have been developing the granular powder production technology. Since the granular powders have excellent fluidity owing to the spherical shape, there is the possibility of modifying scattering and adcering of the powder in the process equipment. In this paper, spray pyrolysis process in adopted as the process of manufacturing the granular powders and the basic feasibility study has been carried out. The experimental results show that the manufactured granular powders have excellent fluidity and the diameter of the powders is controllable. Furthermore, high density pellets are formed by sintering the powders. Thus, it is clarified that this process is promising for the actual MOX fuel fabrication. (author)

Vibration-Assisted Handling of Dry Fine Powders

Directory of Open Access Journals (Sweden)

Paul Dunst

2018-04-01

Full Text Available Since fine powders tend strongly to adhesion and agglomeration, their processing with conventional methods is difficult or impossible. Typically, in order to enable the handling of fine powders, chemicals are added to increase the flowability and reduce adhesion. This contribution shows that instead of additives also vibrations can be used to increase the flowability, to reduce adhesion and cohesion, and thus to enable or improve processes such as precision dosing, mixing, and transport of very fine powders. The methods for manipulating powder properties are described in detail and prototypes for experimental studies are presented. It is shown that the handling of fine powders can be improved by using low-frequency, high-frequency or a combination of low- and high-frequency vibration.

Circumstances of falls and falls-related injuries in a cohort of older patients following hospital discharge

Directory of Open Access Journals (Sweden)

Hill AM

2013-06-01

Full Text Available Anne-Marie Hill,1 Tammy Hoffmann,2,3 Terry P Haines4,51School of Physiotherapy, Institute for Health Research, The University of Notre Dame Australia, Fremantle, WA, 2Centre for Research in Evidence-Based Practice, Faculty of Health Sciences and Medicine, Bond University, Gold Coast, QLD, 3School of Health and Rehabilitation Sciences, The University of Queensland, 4School of Primary Health Care, Monash University, Melbourne, VIC, 5Allied Health Research Unit, Kingston Centre, Southern Health, Clayton, VIC, AustraliaBackground: Older people are at increased risk of falls after hospital discharge. This study aimed to describe the circumstances of falls in the six months after hospital discharge and to identify factors associated with the time and location of these falls.Methods: Participants in this randomized controlled study comprised fallers (n = 138 who were part of a prospective observational cohort (n = 343 nested within a randomized controlled trial (n = 1206. The study tested patient education on falls prevention in hospital compared with usual care in older patients who were discharged from hospital and followed for six months after hospital discharge. The outcome measures were number of falls, falls-related injuries, and the circumstances of the falls, measured by use of a diary and a monthly telephone call to each participant.Results: Participants (mean age 80.3 ± 8.7 years reported 276 falls, of which 150 (54.3% were injurious. Of the 255 falls for which there were data available about circumstances, 190 (74.5% occurred indoors and 65 (25.5% occurred in the external home environment or wider community. The most frequent time reported for falls was the morning (between 6 am and 10 am when 79 (28.6% falls, including 49 (32.7% injurious falls, occurred. The most frequently reported location for falls (n = 80, 29.0%, including injurious falls (n = 42, 28.0%, was the bedroom. Factors associated with falling in the bedroom included

Prevention of falls in nursing homes: subgroup analyses of a randomized fall prevention trial.

Science.gov (United States)

Rapp, Kilian; Lamb, Sarah E; Büchele, Gisela; Lall, Ranjit; Lindemann, Ulrich; Becker, Clemens

2008-06-01

To evaluate the effectiveness of a multifactorial fall prevention program in prespecified subgroups of nursing home residents. Secondary analysis of a cluster-randomized, controlled trial. Six nursing homes in Germany. Seven hundred twenty-five long-stay residents; median age 86; 80% female. Staff and resident education on fall prevention, advice on environmental adaptations, recommendation to wear hip protectors, and progressive balance and resistance training. Time to first fall and the number of falls. Falls were assessed during the 12-month intervention period. Univariate regression analyses were performed, including a confirmatory test of interaction. The intervention was more effective in people with cognitive impairment (hazard ratio (HR)=0.49, 95% confidence interval (CI)=0.35-0.69) than in those who were cognitively intact (HR=0.91, 95% CI=0.68-1.22), in people with a prior history of falls (HR=0.47, 95% CI=0.33-0.67) than in those with no prior fall history (HR=0.77, 95% CI=0.58-1.01), in people with urinary incontinence (HR=0.59, 95% CI=0.45-0.77) than in those with no urinary incontinence (HR=0.98, 95% CI=0.68-1.42), and in people with no mood problems (incidence rate ratio (IRR)=0.41, 95% CI=0.27-0.61) than in those with mood problems (IRR=0.74, 95% CI=0.51-1.09). The effectiveness of a multifactorial fall prevention program differed between subgroups of nursing home residents. Cognitive impairment, a history of falls, urinary incontinence, and depressed mood were important in determining response.

Fall risk factors in Parkinson's disease.

Science.gov (United States)

Gray, P; Hildebrand, K

2000-08-01

Parkinson's disease (PD) is a neurodegenerative disorder characterized by tremor, rigidity, bradykinesia, gait disturbance, and postural instability. Patients with PD suffer frequent falls, yet little research has been done to identify risks specific to PD patients. The objective of this study was to identify the risk factors associated with falls for PD patients through the collection of demographic, environmental, and medical information as well as fall diaries completed during a 3-month period. Patients with a diagnosis of idiopathic PD, with and without falls, were included in the study provided they could stand and walk and had no other condition that could predispose them to falls. Of the 118 participants, 59% reported one or more falls. A total of 237 falls were reported. Duration and severity of PD symptoms, particularly freezing, involuntary movements, and walking and postural difficulties, were significantly associated with an increased risk of falls. Other factors associated with falls were postural hypotension and daily intake of alcohol. Forty percent of falls resulted in injury, but serious injury was rare. The findings have implications for reducing the risk of falls through patient education.

Evaluation of ring shear testing as a characterization method for powder flow in small-scale powder processing equipment

DEFF Research Database (Denmark)

Søgaard, Søren Vinter; Pedersen, Troels; Allesø, Morten

2014-01-01

Powder flow in small-scale equipment is challenging to predict. To meet this need, the impact of consolidation during powder flow characterization, the level of consolidation existing during discharge of powders from a tablet press hopper and the uncertainty of shear and wall friction measurements...... normal stress were approximately 200Pa and 114Pa, respectively, in the critical transition from the converging to the lower vertical section of the hopper. The lower limit of consolidation for the shear and wall friction test was approximately 500Pa and 200Pa, respectively. At this consolidation level......, the wall and shear stress resolution influences the precision of the measured powder flow properties. This study highlights the need for an improved experimental setup which would be capable of measuring the flow properties of powders under very small consolidation stresses with a high shear stress...

Fabrication of nuclear fuel by powder injection moulding: Study of the binders systems and the de-binding of feedstock containing actinide powder

International Nuclear Information System (INIS)

Bricout, J.

2012-01-01

Powder Injection Moulding (PIM) is identified as an innovative process for the nuclear fuel fabrication. Technological breakthrough compared to the current process of powder metallurgy, the impact of actinide powder's specificities on the different steps of PIM is performed. Alumina powders simulating actinide powder have been implemented with a reference binders system. Thermal and rheological studies show the injectability and the de-binding of feedstocks with adequate solid loading (≥50 %vol), thanks to the de-agglomeration during the mixing step, which allow to obtain net shape fuel pellet. Specific surface area of powders, acting as a key role in behaviour's feedstocks, has been integrated in analysis models of viscosity prediction according to the shear rate. Also conducted studies on uranium oxide powder show that the selected binders systems, which have a compatible rheological behaviour with PIM process, impact the de-agglomeration of powder and final microstructure of the fuel pellet, consistent with the results obtained on alumina powders. Independent behaviour of binders and uranium oxide powder, showing no adverse chemical reaction against the PIM process, show a residual mass of carbon of about 150 ppm after sintering. Binders system using polystyrene, resistant to radiolysis phenomena and loadable more than 50 %(vol) of actinide powder, shows the promising potential of PIM process for the fuel fabrication. (author) [fr

Comparison of Walking, Muscle Strength, Balance, and Fear of Falling Between Repeated Fall Group, One-time Fall Group, and Nonfall Group of the Elderly Receiving Home Care Service.

Science.gov (United States)

Jeon, MiYang; Gu, Mee Ock; Yim, JongEun

2017-12-01

The purpose of this study was to provide information to develop a program to prevent repeated falls by analyzing the difference in gait, muscle strength, balance, and fear of falling according to their fall experience. The study subjects were 110 elderly individuals aged over 60 years who agreed to their participation in this research. The study participants were categorized into a repeated fall group (n = 40), a one-time fall group (n = 15), and a nonfall group (n = 46) of the elderly. Measurements of gait, muscle strength, balance, and fear of falling were taken in each group. With regard to gait, there were significant differences among three groups in gait cycle (F = 3.50, p = .034), speed (F = 13.06, p balance, the nonfall group had significantly greater results than the one-time fall group and repeated fall group in dynamic balance (F = 10.80, p balance (F = 8.20, p = .001). In the case of the fear of falling, the repeated fall group had significantly higher score than other two groups (F = 20.62, p fall risk factors to enhance gait and balance and lower body muscle strength and reduce the fear of falling to prevent repeated incidences of falls in this population. Copyright © 2017. Published by Elsevier B.V.

Spray drying of beryllium oxide powder

International Nuclear Information System (INIS)

Sepulveda, J.L.; Kahler, D.A.

1991-01-01

Forming of beryllia ceramics through dry pressing requires the agglomeration of the powder through spray drying. To produce high quality fired ceramics it is necessary to disperse/grind the primary powder prior to binder addition. Size reduction of the powder is accomplished using an aqueous system in Vibro-Energy mills (VEM) charged with beryllia media to minimize contamination. Two VEM mills of different size were used to characterize the grinding operation. Details of the grinding kinetics are described within the context of the Macroscopic Population Balance Model approach. Spray drying of the ceramic slurry was accomplished with both a centrifugal atomizer and a two fluid nozzle atomizer. Two different spray dryers were used. Important operating parameters affecting the size distribution of the spray dried powder are discussed

Method of producing radioactive carbon powder

International Nuclear Information System (INIS)

Imamura, Y.

1980-01-01

Carbon powder, placed in a hermetically closed apparatus under vacuum together with radium ore, adsorbs radon gas emanating from the radium ore thus producing a radioactive carbonaceous material, the radioactivity of which is due to the presence of adsorbed radon. The radioactive carbon powder thus obtained has excellent therapeutical efficacy and is suitable for a variety of applications because of the mild radioactivity of radon. Radium ore permits substantially limitlessly repeated production of the radioactive carbon powder

The relationship of intrinsic fall risk factors to a recent history of falling in older women with osteoporosis.

Science.gov (United States)

Arnold, Cathy M; Busch, Angela J; Schachter, Candice L; Harrison, Liz; Olszynski, Wojciech

2005-07-01

Cross-sectional descriptive analysis investigating intrinsic fall risk factors in postmenopausal women with osteoporosis. To examine the relationships between history of recent falls and balance, pain, quality of life, function, posture, strength, and mobility. Women with osteoporosis who fall are at a high risk of fracture due to decreased bone strength. Identifying fall risk factors for older women with osteoporosis is a crucial step in decreasing the incidence of falls and fracture. METHOD AND MEASURES: Seventy-three women over 60 years of age with established osteoporosis participated in comprehensive testing of fall history, physical function, and quality of life. Significant correlations were found between a recent history of falls and degree of kyphosis (r = 0.29), fear of falls/emotional status (r = -0.27), and balance (r = -0.27). Degree of kyphosis and fear of falls/emotional status explained 20% of the variance of recent fall history using binary logistic regression. Women with an increased kyphosis were more likely to have had a recent fall (odds ratio [OR], 1.17; 95% CI, 1.03-1.34) and those with better emotional status and less fear of falling were less likely to have had a recent fall (OR, 0.61; 95% CI, 0.38-0.97). Increased thoracic kyphosis and fear of falling are 2 intrinsic factors associated with recent falls in women with osteoporosis. To design more effective interventions to decrease fall risk in this population, future prospective, longitudinal studies should monitor kyphosis, fear of falling, balance reactions, and other potential risk factors not identified in this study.

The efficacy of fall-risk-increasing drug (FRID) withdrawal for the prevention of falls and fall-related complications: protocol for a systematic review and meta-analysis.

Science.gov (United States)

Lee, Justin Yusen; Holbrook, Anne

2017-02-20

Despite limited evidence of effectiveness, withdrawal (discontinuation or dose reduction) of high risk medications known as "fall-risk increasing drugs" (FRIDs) is typically conducted as a fall prevention strategy based on presumptive benefit. Our objective is to determine the efficacy of fall-risk increasing drugs (FRIDs) withdrawal on the prevention of falls and fall-related complications. We will search for all published and unpublished randomized controlled trials evaluating the effect of FRID withdrawal compared to usual care on the rate of falls, incidence of falls, fall-related injuries, fall-related fractures, fall-related hospitalizations, or adverse effects related to the intervention in adults aged 65 years or older. Electronic database searches will be conducted in MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), and CINAHL. A grey literature search will be conducted including clinical trial registries and conference proceedings and abstracts. Two reviewers will independently perform in duplicate citation screening, full-text review, data abstraction, and risk of bias assessment. Conflicts will be resolved through team discussion or by a third reviewer if no consensus can be reached. The Grades of Recommendation, Assessment, Development and Evaluation (GRADE) criteria will be used to independently rate overall confidence in effect estimates for each outcome. Results will be synthesized descriptively, and a random effects meta-analysis will be conducted for each outcome if studies are deemed similar methodologically, clinically, and statistically. We will attempt to determine whether a FRID withdrawal strategy alone is effective at preventing falls in older adults. Our results will be used to optimize and focus fall prevention strategies and initiatives internationally with a goal of improving the health of older adults. PROSPERO CRD42016040203.

Preparation techniques for ceramic waste form powder

International Nuclear Information System (INIS)

Hash, M.C.; Pereira, C.; Lewis, M.A.

1997-01-01

The electrometallurgical treatment of spent nuclear fuels result in a chloride waste salt requiring geologic disposal. Argonne National Laboratory (ANL) is developing ceramic waste forms which can incorporate this waste. Currently, zeolite- or sodalite-glass composites are produced by hot isostatic pressing (HIP) techniques. Powder preparations include dehydration of the raw zeolite powders, hot blending of these zeolite powders and secondary additives. Various approaches are being pursued to achieve adequate mixing, and the resulting powders have been HIPed and characterized for leach resistance, phase equilibria, and physical integrity

Prospective study of falls and risk factors for falls in adults with advanced cancer.

LENUS (Irish Health Repository)

Stone, Carol A

2012-06-10

Retrospective studies of inpatients with cancer suggest that a cancer diagnosis confers a high risk of falls. In adults with advanced cancer, we aimed to prospectively document the incidence of falls, identify the risk factors, and determine if falls in this population occur predominantly in older patients.

Community College Estimated Growth: Fall 2010

Science.gov (United States)

Phillippe, Kent; Mullin, Christopher M.

2011-01-01

A survey from the American Association of Community Colleges (AACC) found that enrollment growth in fall 2010 slowed its pace at community colleges, increasing 3.2% from the previous year. This contrasts with more dramatic increases in recent years: more than 11% between fall 2008 and fall 2009, and nearly 17% between fall 2007 and fall 2009,…

Synthesis of a TiBw/Ti6Al4V composite by powder compact extrusion using a blended powder mixture

Energy Technology Data Exchange (ETDEWEB)

Lu, Huiyang, E-mail: hl209@waikato.ac.nz [Waikato Center for Advanced Materials, School of Engineering, University of Waikato, Hamilton (New Zealand); Zhang, Deliang, E-mail: zhangdeliang@sjtu.edu.cn [State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai (China); Gabbitas, Brian, E-mail: briang@waikato.ac.nz [Waikato Center for Advanced Materials, School of Engineering, University of Waikato, Hamilton (New Zealand); Yang, Fei, E-mail: fyang@waikato.ac.nz [Waikato Center for Advanced Materials, School of Engineering, University of Waikato, Hamilton (New Zealand); Matthews, Steven, E-mail: S.Matthews@massey.ac.nz [School of Engineering and Advanced Technology, Massey University, Auckland (New Zealand)

2014-09-01

Highlights: • TiB/Ti6Al4V composites were prepared from extruded BE powders. • Different starting powders affected the morphologies of TiB whiskers formed in-situ. • A TiB/Ti6Al4V composite with TiB whiskers had good strength and ductility. • The strength and ductility achieved were superior to those obtained by other methods. - Abstract: A Ti–6 wt%Al–4 wt%V alloy (Ti6Al4V) matrix composite, reinforced by in situ synthesized TiB whiskers (TiBw) has been successfully fabricated by powder compact extrusion using a blended powder mixture. The microstructural characterization of the various extruded samples showed that the different starting powders, pre-alloyed powder plus boron powder or titanium plus Al–40V master alloy powder plus boron powder, had a significant effect on the morphology of the in situ synthesized TiB whiskers. It is also evident that the TiB whiskers affect the microstructural evolution of the Ti6Al4V matrix. The tensile test results indicated that the composite with a dispersion of fine TiB whiskers with high aspect ratios exhibited a high ultimate tensile stress (UTS) and yield stress (YS) of 1436 MPa and 1361 MPa, respectively, a reasonably good tensile ductility reflected by an elongation to fracture of 5.6% was also achieved. This is a significant improvement compared with as-extruded monolithic Ti6Al4V alloy produced in this study.

Synthesis of a TiBw/Ti6Al4V composite by powder compact extrusion using a blended powder mixture

International Nuclear Information System (INIS)

Lu, Huiyang; Zhang, Deliang; Gabbitas, Brian; Yang, Fei; Matthews, Steven

2014-01-01

Highlights: • TiB/Ti6Al4V composites were prepared from extruded BE powders. • Different starting powders affected the morphologies of TiB whiskers formed in-situ. • A TiB/Ti6Al4V composite with TiB whiskers had good strength and ductility. • The strength and ductility achieved were superior to those obtained by other methods. - Abstract: A Ti–6 wt%Al–4 wt%V alloy (Ti6Al4V) matrix composite, reinforced by in situ synthesized TiB whiskers (TiBw) has been successfully fabricated by powder compact extrusion using a blended powder mixture. The microstructural characterization of the various extruded samples showed that the different starting powders, pre-alloyed powder plus boron powder or titanium plus Al–40V master alloy powder plus boron powder, had a significant effect on the morphology of the in situ synthesized TiB whiskers. It is also evident that the TiB whiskers affect the microstructural evolution of the Ti6Al4V matrix. The tensile test results indicated that the composite with a dispersion of fine TiB whiskers with high aspect ratios exhibited a high ultimate tensile stress (UTS) and yield stress (YS) of 1436 MPa and 1361 MPa, respectively, a reasonably good tensile ductility reflected by an elongation to fracture of 5.6% was also achieved. This is a significant improvement compared with as-extruded monolithic Ti6Al4V alloy produced in this study

(YSZ) powders

Indian Academy of Sciences (India)

Unknown

109–114. © Indian Academy of Sciences. 109 ... Materials Science Division, Bhabha Atomic Research Centre, Mumbai 400 085, India .... pensions of 900°C calcined YSZ powders. .... The sintered density data of the compacts (sintered at.

Internal Friction Angle of Metal Powders

Directory of Open Access Journals (Sweden)

Jiri Zegzulka

2018-04-01

Full Text Available Metal powders are components with multidisciplinary usage as their application is very broad. Their consistent characterization across all disciplines is important for ensuring repeatable and trouble-free processes. Ten metal powders were tested in the study. In all cases, the particle size distribution and morphology (scanning electron microscope—SEM photos were determined. The aim of this work was to inspect the flow behavior of metal powders through another measured characteristic, namely the angle of internal friction. The measured values of the effective internal friction angle in the range 28.6–32.9°, together with the spherical particle shape and the particle size distribution, revealed the likely dominant mode of the metal particle transfer mechanism for stainless steel 316L, zinc and aluminum powder. This third piston flow mechanism is described and illustrated in detail. The angle of internal friction is mentioned as another suitable parameter for the characterization of metal powders, not only for the relative simplicity of the determination but also for gaining insight into the method of the movement of individual particles during the flow.

Device for preparing combinatorial libraries in powder metallurgy.

Science.gov (United States)

Yang, Shoufeng; Evans, Julian R G

2004-01-01

This paper describes a powder-metering, -mixing, and -dispensing mechanism that can be used as a method for producing large numbers of samples for metallurgical evaluation or electrical or mechanical testing from multicomponent metal and cermet powder systems. It is designed to make use of the same commercial powders that are used in powder metallurgy and, therefore, to produce samples that are faithful to the microstructure of finished products. The particle assemblies produced by the device could be consolidated by die pressing, isostatic pressing, laser sintering, or direct melting. The powder metering valve provides both on/off and flow rate control of dry powders in open capillaries using acoustic vibration. The valve is simple and involves no relative movement, avoiding seizure with fine powders. An orchestra of such valves can be arranged on a building platform to prepare multicomponent combinatorial libraries. As with many combinatorial devices, identification and evaluation of sources of mixing error as a function of sample size is mandatory. Such an analysis is presented.

Intrinsic factors associated with pregnancy falls.

Science.gov (United States)

Wu, Xuefang; Yeoh, Han T

2014-10-01

Approximately 25% to 27% of women sustain a fall during pregnancy, and falls are associated with serious injuries and can affect pregnancy outcomes. The objective of the current study was to identify intrinsic factors associated with pregnancy that may contribute to women's increased risk of falls. A literature search (Medline and Pubmed) identified articles published between January 1980 and June 2013 that measured associations between pregnancy and fall risks, using an existing fall accident investigation framework. The results indicated that physiological, biomechanical, and psychological changes associated with pregnancy may influence the initiation, detection, and recovery phases of falls and increase the risk of falls in this population. Considering the logistic difficulties and ethnic concerns in recruiting pregnant women to participate in this investigation of fall risk factors, identification of these factors could establish effective fall prevention and intervention programs for pregnant women and improve birth outcomes. [Workplace Health Saf 2014;62(10):403-408.]. Copyright 2014, SLACK Incorporated.

Fall Risk Assessment Predicts Fall-Related Injury, Hip Fracture, and Head Injury in Older Adults.

Science.gov (United States)

Nilsson, Martin; Eriksson, Joel; Larsson, Berit; Odén, Anders; Johansson, Helena; Lorentzon, Mattias

2016-11-01

To investigate the role of a fall risk assessment, using the Downton Fall Risk Index (DFRI), in predicting fall-related injury, fall-related head injury and hip fracture, and death, in a large cohort of older women and men residing in Sweden. Cross sectional observational study. Sweden. Older adults (mean age 82.4 ± 7.8) who had a fall risk assessment using the DFRI at baseline (N = 128,596). Information on all fall-related injuries, all fall-related head injuries and hip fractures, and all-cause mortality was collected from the Swedish Patient Register and Cause of Death Register. The predictive role of DFRI was calculated using Poisson regression models with age, sex, height, weight, and comorbidities as covariates, taking time to outcome or end of study into account. During a median follow-up of 253 days (interquartile range 90-402 days) (>80,000 patient-years), 15,299 participants had a fall-related injury, 2,864 a head injury, and 2,557 a hip fracture, and 23,307 died. High fall risk (DFRI ≥3) independently predicted fall-related injury (hazard ratio (HR) = 1.43, 95% confidence interval (CI) = 1.39-1.49), hip fracture (HR = 1.51, 95% CI =1.38-1.66), head injury (HR = 1.12, 95% CI = 1.03-1.22), and all-cause mortality (HR = 1.39, 95% CI = 1.35-1.43). DFRI more strongly predicted head injury (HR = 1.29, 95% CI = 1.21-1.36 vs HR = 1.08, 95% CI = 1.04-1.11) and hip fracture (HR = 1.41, 95% CI = 1.30-1.53 vs HR = 1.08, 95% CI = 1.05-1.11) in 70-year old men than in 90-year old women (P Fall risk assessment using DFRI independently predicts fall-related injury, fall-related head injury and hip fracture, and all-cause mortality in older men and women, indicating its clinical usefulness to identify individuals who would benefit from interventions. © 2016 The Authors. The Journal of the American Geriatrics Society published by Wiley Periodicals, Inc. on behalf of The American Geriatrics Society.

Preventing falls in hospital.

Science.gov (United States)

Pearce, Lynne

2017-02-27

Essential facts Falls are the most frequent adverse event reported in hospitals, usually affecting older patients. Every year, more than 240,000 falls are reported in acute hospitals and mental health trusts in England and Wales, equivalent to more than 600 a day, according to the Royal College of Physicians (RCP). But research shows that when nurses, doctors and therapists work together, falls can be reduced by 20-30%.

Preventing Falls in Older Persons.

Science.gov (United States)

Moncada, Lainie Van Voast; Mire, L Glen

2017-08-15

The American Geriatrics Society and British Geriatrics Society recommend that all adults older than 65 years be screened annually for a history of falls or balance impairment. The U.S. Preventive Services Task Force and American Academy of Family Physicians recommend exercise or physical therapy and vitamin D supplementation to prevent falls in community-dwelling older adults who are at increased risk of falls. Although the U.S. Preventive Services Task Force and American Academy of Family Physicians do not recommend routine multifactorial intervention to prevent falls in all community-dwelling older adults, they state that it may be appropriate in individual cases. The Centers for Disease Control and Prevention developed an algorithm to aid in the implementation of the American Geriatrics Society/British Geriatrics Society guideline. The algorithm suggests assessment and multifactorial intervention for those who have had two or more falls or one fall-related injury. Multifactorial interventions should include exercise, particularly balance, strength, and gait training; vitamin D supplementation with or without calcium; management of medications, especially psychoactive medications; home environment modification; and management of postural hypotension, vision problems, foot problems, and footwear. These interventions effectively decrease falls in the community, hospital, and nursing home settings. Fall prevention is reimbursed as part of the Medicare Annual Wellness Visit.

Preparation procedure for spherical titanium powders by RF induction plasma

International Nuclear Information System (INIS)

Gu Zhongtao; Jin Yuping; Ye Gaoying

2011-01-01

The paper uses the single-factor method for the study of spherical titanium powder preparation process. Titanium powders with excellent sphericity can be prepared through controlling and regulating the radio frequency plasma anode working current and voltage, central gas flow rate, sheath gas flow rate, powder-carrying gas flow rate, negative ventilation pressure and powder feed rate, etc. Spheroidization of titanium powders with a size of (17.0±2.0) μm is performed by radio frequency plasma technology. With the increase of negative ventilation pressure, the spheroidization rate of titanium powders increases firstly and then decreases rapidly at the turning point around 1800 Pa. With the rate of powder feed increasing, the spheroidization rate of titanium powders increases firstly. When the powder feed rate is greater than 90.0 g/min, the spheroidization rate of titanium powders reduces rapidly as the powder feed rate increases. (authors)

Electrical conductivity of metal powders under pressure

Science.gov (United States)

Montes, J. M.; Cuevas, F. G.; Cintas, J.; Urban, P.

2011-12-01

A model for calculating the electrical conductivity of a compressed powder mass consisting of oxide-coated metal particles has been derived. A theoretical tool previously developed by the authors, the so-called `equivalent simple cubic system', was used in the model deduction. This tool is based on relating the actual powder system to an equivalent one consisting of deforming spheres packed in a simple cubic lattice, which is much easier to examine. The proposed model relates the effective electrical conductivity of the powder mass under compression to its level of porosity. Other physically measurable parameters in the model are the conductivities of the metal and oxide constituting the powder particles, their radii, the mean thickness of the oxide layer and the tap porosity of the powder. Two additional parameters controlling the effect of the descaling of the particle oxide layer were empirically introduced. The proposed model was experimentally verified by measurements of the electrical conductivity of aluminium, bronze, iron, nickel and titanium powders under pressure. The consistency between theoretical predictions and experimental results was reasonably good in all cases.

Study of nuclear fuel powders forming by axial compaction

International Nuclear Information System (INIS)

Fourcade, J.

2002-12-01

Nuclear fuel powders forming, although perfectly dominated, fail to make compacts without density gradients. Density heterogeneities induce diametric deformations during firing which force manufacturers to adjust shape with a high cost machining stage. Manufacturing process improvement is a major project to obtain perfectly shaped pellets and reduce their cost. One way of investigation of this project is the study of powders compaction mechanisms to understand and improve their behaviour. The goal of this study is to identify the main mechanisms linked with powder properties that act on pressing. An empirical model is developed to predict pellet deformations from a single compaction test. This model has to link powder properties with their compaction behaviour. Then, compaction tests identify the main mechanisms whereas a contact dynamic program is used to explain them. These works, done to improve the understanding in powders behaviour, focus on powders agglomeration state and macroscopic particles arrangement during the die filling stage. Actually, for granulated powders, granules cohesion act on the powder bed behaviour under pressure. The first particles arrangement is responsible for the first transfer directions into the powder and so for its transfer homogeneity and isotropy. As a consequence, the knowledge of all the macroscopic powder properties is essential to understand and improve the manufacturing process. Moreover, tests on UO 2 powders have shown that it is better to use granulated powders with spherical granules, short size distribution and granules cohesion according with compaction pressure to improve compact homogeneity of densification. (author)

Radiotreated cocoa powder for frozen elaboration

International Nuclear Information System (INIS)

Rodriguez Jorge, M.; Alvarez Gil, M.; Prieto Miranda, E.; Morales Valladares, M.

1995-01-01

The aim of the present papers is to study the possibilities of 2.0 kGy gamma radiotreated cocoa powder to be used in the elaboration of powder mixture for the preparation of chocolate frozen. Three industrial productions were carried out. Microbiological and organoleptic evaluations of the final product were performed. The results showed that the use of radurized cocoa powder in the frozen elaboration is feasible. A good hygienic quality of this product was obtained and no organoleptic alterations were detected [es

Spinal sagittal contour affecting falls: cut-off value of the lumbar spine for falls.

Science.gov (United States)

Ishikawa, Yoshinori; Miyakoshi, Naohisa; Kasukawa, Yuji; Hongo, Michio; Shimada, Yoichi

2013-06-01

Spinal deformities reportedly affect postural instability or falls. To prevent falls in clinical settings, the determination of a cut-off angle of spinal sagittal contour associated with increase risk for falls would be useful for screening for high-risk fallers. The purpose of this study was to calculate the spinal sagittal contour angle associated with increased risk for falls during medical checkups in community dwelling elders. The subjects comprised 213 patients (57 men, 156 women) with a mean age of 70.1 years (range, 55-85 years). The upright and flexion/extension thoracic kyphosis and lumbar lordosis angles, and the spinal inclination were evaluated with SpinalMouse(®). Postural instability was evaluated by stabilometry, using the total track length (LNG), enveloped areas (ENV), and track lengths in the lateral and anteroposterior directions (X LNG and Y LNG, respectively). The back extensor strength (BES) was measured using a strain-gauge dynamometer. The relationships among the parameters were analyzed statistically. Age, lumbar lordosis, spinal inclination, LNG, X LNG, Y LNG, and BES were significantly associated with falls (Pfalls about lumbar lordosis angles revealed that angles of 3° and less were significant for falls. The present findings suggest that increased age, spinal inclination, LNG, X LNG, Y LNG, and decreased BES and lumbar lordosis, are associated with falls. An angle of lumbar lordosis of 3° or less was associated with falls in these community-dwelling elders. Copyright © 2012 Elsevier B.V. All rights reserved.

Clinical and Community Strategies to Prevent Falls and Fall-Related Injuries Among Community-Dwelling Older Adults.

Science.gov (United States)

Taylor-Piliae, Ruth E; Peterson, Rachel; Mohler, Martha Jane

2017-09-01

Falls in older adults are the result of several risk factors across biological and behavioral aspects of the person, along with environmental factors. Falls can trigger a downward spiral in activities of daily living, independence, and overall health outcomes. Clinicians who care for older adults should screen them annually for falls. A multifactorial comprehensive clinical fall assessment coupled with tailored interventions can result in a dramatic public health impact, while improving older adult quality of life. For community-dwelling older adults, effective fall prevention has the potential to reduce serious fall-related injuries, emergency room visits, hospitalizations, institutionalization, and functional decline. Copyright © 2017 Elsevier Inc. All rights reserved.

The efficacy of fall-risk-increasing drug (FRID withdrawal for the prevention of falls and fall-related complications: protocol for a systematic review and meta-analysis

Directory of Open Access Journals (Sweden)

Justin Yusen Lee

2017-02-01

Full Text Available Abstract Background Despite limited evidence of effectiveness, withdrawal (discontinuation or dose reduction of high risk medications known as “fall-risk increasing drugs” (FRIDs is typically conducted as a fall prevention strategy based on presumptive benefit. Our objective is to determine the efficacy of fall-risk increasing drugs (FRIDs withdrawal on the prevention of falls and fall-related complications. Methods/design We will search for all published and unpublished randomized controlled trials evaluating the effect of FRID withdrawal compared to usual care on the rate of falls, incidence of falls, fall-related injuries, fall-related fractures, fall-related hospitalizations, or adverse effects related to the intervention in adults aged 65 years or older. Electronic database searches will be conducted in MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL, and CINAHL. A grey literature search will be conducted including clinical trial registries and conference proceedings and abstracts. Two reviewers will independently perform in duplicate citation screening, full-text review, data abstraction, and risk of bias assessment. Conflicts will be resolved through team discussion or by a third reviewer if no consensus can be reached. The Grades of Recommendation, Assessment, Development and Evaluation (GRADE criteria will be used to independently rate overall confidence in effect estimates for each outcome. Results will be synthesized descriptively, and a random effects meta-analysis will be conducted for each outcome if studies are deemed similar methodologically, clinically, and statistically. Discussion We will attempt to determine whether a FRID withdrawal strategy alone is effective at preventing falls in older adults. Our results will be used to optimize and focus fall prevention strategies and initiatives internationally with a goal of improving the health of older adults. Systematic review registration PROSPERO CRD

Preparation and utilization of metal oxide fine powder

Energy Technology Data Exchange (ETDEWEB)

Kim, Joon Soo; Jang, Hee Dong; Lim, Young Woong; Kim, Sung Don; Lee, Hi Sun; Lee, Hoo In; Kim, Chul Joo; Shim, Gun Joo; Jang, Dae Kyu [Korea Inst. of Geology Mining and Materials, Taejon (Korea, Republic of)

1995-12-01

Metal oxide fine powders finds many applications in industry as new materials. It is very much necessary for the development of such powders to improve the domestic industry. The purpose of present research is to develop a process for the preparation and utilization of metal oxide fine powder. This project is consisted of two main subjects. (1) Production of ultrafine metal oxide powder: Ultrafine metal oxide powder is defined as a metal oxide powder of less than 100 nanometer in particle size. Experiments for the control of particle size and distributions in the various reaction system and compared with results of (2 nd year research). Various reaction systems were adopted for the development of feasible process. Ultrafine particles could be prepared even higher concentration of TiCl{sub 4} and lower gas flowrate compared to TiCl{sub 4}-O{sub 2} system in the TiCl{sub 4}-Air-H{sub 2}O system. Ultrafine Al{sub 2}O{sub 3} powders also prepared with the change of concentration and gas flowrate. Experiments on the treatment of surface characteristics of ultrafine TiO{sub 2} powders were investigated using esterification and surface treating agents. A mathematical model that can predict the particle size and distribution was also developed. (2) Preparation of cerium oxide for high-grade polishing powder: Used cerium polishing powder was recycled for preparation of high grade cerium oxide polishing powder. Also, cerium hydroxide which was generated as by-product in processing of monazite ore was used as another material. These two materials were leached respectively by using acid, and the precipitate was gained in each leached solution by adjusting pH of the solution, and by selective crystallization. These precipitates were calcined to make high grade cerium oxide polishing powder. The effect of several experimental variables were investigated, and the optimum conditions were obtained through the experiments. (author). 81 refs., 49 figs., 27 tabs.

Preventing Falls and Related Fractures

Science.gov (United States)

... slowed reflexes. Drinking alcoholic beverages also increases the risk of falling. Alcohol slows reflexes and response time; causes dizziness, sleepiness, or lightheadedness; alters balance; and encourages risky behaviors that can lead to falls. The Force and Direction of a Fall The ...

21 CFR 169.182 - Vanilla-vanillin powder.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Vanilla-vanillin powder. 169.182 Section 169.182... Dressings and Flavorings § 169.182 Vanilla-vanillin powder. (a) Vanilla-vanillin powder conforms to the... § 169.3(c) contained therein, the article also contains not more than 1 ounce of added vanillin. (b) The...

Shock-induced modification of inorganic powders

International Nuclear Information System (INIS)

Graham, R.A.; Morosin, B.; Venturini, E.L.; Beauchamp, E.K.; Hammetter, W.F.

1984-01-01

The results of studies performed to quantify the characteristics of TiO2, ZrO2 and Si3N4 powders exposed to explosive loading and post-shock analysis are reported. The shocks were produced with plane wave generators and explosive pads impinging on steel disks, a copper recovery fixture, and then the samples. Peak pressures of 13 and 17 GPa were attained, along with 40 GPz at the center of the powder cavity. Data are provided on the changes occurring during the explosive densification and X-ray and paramagnetic studies of the products. Only fractured disks were obtained in the trials. The shock-treated materials were more free flowing than the original powders, which were fluffy. Post-shock annealing was a significant feature of the treated powders

Virtual obstacle crossing: Reliability and differences in stroke survivors who prospectively experienced falls or no falls.

Science.gov (United States)

Punt, Michiel; Bruijn, Sjoerd M; Wittink, Harriet; van de Port, Ingrid G; Wubbels, Gijs; van Dieën, Jaap H

2017-10-01

Stroke survivors often fall during walking. To reduce fall risk, gait testing and training with avoidance of virtual obstacles is gaining popularity. However, it is unknown whether and how virtual obstacle crossing is associated with fall risk. The present study assessed whether obstacle crossing characteristics are reliable and assessed differences in stroke survivors who prospectively experienced falls or no falls. We recruited twenty-nine community dwelling chronic stroke survivors. Participants crossed five virtual obstacles with increasing lengths. After a break, the test was repeated to assess test-retest reliability. For each obstacle length and trial, we determined; success rate, leading limb preference, pre and post obstacle distance, margins of stability, toe clearance, and crossing step length and speed. Subsequently, fall incidence was monitored using a fall calendar and monthly phone calls over a six-month period. Test-retest reliability was poor, but improved with increasing obstacle-length. Twelve participants reported at least one fall. No association of fall incidence with any of the obstacle crossing characteristics was found. Given the absence of height of the virtual obstacles, obstacle avoidance may have been relatively easy, allowing participants to cross obstacles in multiple ways, increasing variability of crossing characteristics and reducing the association with fall risk. These finding cast some doubt on current protocols for testing and training of obstacle avoidance in stroke rehabilitation. Copyright © 2017 Elsevier B.V. All rights reserved.

[The species traceability of the ultrafine powder and the cell wall-broken powder of herbal medicine based on DNA barcoding].

Science.gov (United States)

Xiang, Li; Tang, Huan; Cheng, Jin-le; Chen, Yi-long; Deng, Wen; Zheng, Xia-sheng; Lai, Zhi-tian; Chen, Shi-lin

2015-12-01

Ultrafine powder and cell wall-broken powder of herbal medicine lack of the morphological characters and microscopic identification features. This makes it hard to identify herb's authenticity with traditional methods. We tested ITS2 sequence as DNA barcode in identification of herbal medicine in ultrafine powder and cell wall-broken powder in this study. We extracted genomic DNAs of 93 samples of 31 representative herbal medicines (28 species), which include whole plant, roots and bulbs, stems, leaves, flowers, fruits and seeds. The ITS2 sequences were amplified and sequenced bidirectionally. The ITS2 sequences were identified using Basic Local Alignment Search Tool (BLAST) method in the GenBank database and DNA barcoding system to identify the herbal medicine. The genetic distance was analyzed using the Kimura 2-parameter (K2P) model and the Neighbor-joining (NJ) phylogenetic tree was constructed using MEGA 6.0. The results showed that DNA can be extracted successfully from 93 samples and high quality ITS2 sequences can be amplified. All 31 herbal medicines can get correct identification via BLAST method. The ITS2 sequences of raw material medicines, ultrafine powder and cell wall-broken powder have same sequence in 26 herbal medicines, while the ITS2 sequences in other 5 herbal medicines exhibited variation. The maximum intraspecific genetic-distances of each species were all less than the minimum interspecific genetic distances. ITS2 sequences of each species are all converged to their standard DNA barcodes using NJ method. Therefore, using ITS2 barcode can accurately and effectively distinguish ultrafine powder and cell wall-broken powder of herbal medicine. It provides a new molecular method to identify ultrafine powder and cell wall-broken powder of herbal medicine in the quality control and market supervision.

Approach to Fall in Elderly Population

Directory of Open Access Journals (Sweden)

Mehmet Ilkin Naharci

2009-10-01

Full Text Available Falls are one of the geriatric syndromes which occur commonly and significantly increase morbidity and mortality rates in elderly. The incidence of falls increases with age. Falls usually occur when impairments in cognitive, behavioral, and executive function begin. The incidence of fall is between 30 and 40 percent of community-dwelling people and approximately 50 percent of individuals in the long-term care setting over the age of 65 years. Fracture (hip, arm, wrist, pelvis, head trauma or major lacerations, as defined serious wounding, occur 10-25% of elderly cases. Fall is overlooked in clinical examination due to various reasons; the patient never mentions the event to a doctor; there is no injury at the time of the fall; the doctor fails to ask the patient about a history of falls; or either doctor or patient erroneously believes that falls are an inevitable part of the aging process. Elderly give not usually any self-information about fall, for this reason, all older patients should be asked at least once per year about falls and should be assessed in terms of balance and gait disorders. There are many distinct causes for falls in old people. Falls in older individuals occur when a threat to the normal homeostatic mechanisms that maintain postural stability is superimposed on underlying age-related declines in balance, ambulation, and cardiovascular function. This factor may be an acute illness (eg, fever, water loss, arrhythmia, a new medication, an environmental stress (eg, unfamiliar surrounding, or an unsafe walking surface. The elderly person can not cope with happened additional stress. To prevent and decrease the frequency of falls, effective approaches are medical interventions, environmental modifications, education-exercise programs, and assisted device. Detection and amelioration of risk factors can significantly reduce the rate of future falls. The assessment of fall, causing mobility restriction, use of nursing home, and

Spark-plasma sintering and mechanical property of mechanically alloyed NiAl powder compact and ball-milled (Ni+Al) mixed powder compact

International Nuclear Information System (INIS)

Kim, J.S.; Jang, Y.I.; Kwon, Y.S.; Kim, Y.D.; Ahn, I.S.

2001-01-01

Mechanically-alloyed NiAl powder and (Ni+Al) powder mixture prepared by ball-milling were sintered by spark-plasma sintering (SPS) process. Densification behavior and mechanical property were determined from the experimental results and analysis such as changes in linear shrinkage, shrinkage rate, microstructure, and phase during sintering process, Vicker's hardness and transverse rupture strength tests. Densification mechanisms for MA-NiAl powder compact and (Ni+Al) powder mixture were different from each other. While the former showed a rapid increase in densification rate only at higher temperature region of 800-900 o C, the latter revealed firstly a rapid increase in densification rate even at low temperature of 300 o C and a subsequent increase up to 500 o C. Densities of both powder compact (MA and mixture) sintered at 1150 o C for 5 min were 98 and above 99 %, respectively. Sintered bodies were composed mainly of NiAl phase with Ni 3 Al as secondary phase for both powders. Sintered body of MA-NiAl powder showed a very fine grain structure. Crystallite size determined by XRD result and the Sherrer's equation was approximately 80 nm. Vicker's hardness for the sintered bodies of (Ni+Al) powder mixture and MA-NiAl powder were 410±12 H v and 555±10 H v , respectively, whereas TRS values 1097±48 MPa and 1393±75 MPa. (author)

Development and feasibility of falls prevention advice.

Science.gov (United States)

van Harten-Krouwel, Diny; Schuurmans, Marieke; Emmelot-Vonk, Mariëlle; Pel-Littel, Ruth

2011-10-01

This study examined the feasibility of nursing falls prevention advice and factors influencing feasibility. The frequency and seriousness of falls in hospitalised patients are underestimated, and such falls should be preventable because of the presence of professionals. A best practice-based falls prevention advice was developed to decrease the incidence of secondary falls and the incidence of primary falls in the long term and to increase the knowledge of nurses about falls prevention and the seriousness of falls. A descriptive, explorative study. Feasibility of the advice for 30 patients was assessed 82 times (theoretically, three times per patient) by observation and by interviewing nurses, patients and their families. The falls prevention advice was used in 48% of the assessments. There was a difference in use between interventions. Interventions that required more knowledge, communication and extra activities were implemented the least. The absence of materials and knowledge about falls prevention were important determinants of the non-implementation of certain interventions. Before falls prevention advice is implemented, it is important to educate nurses about falls, communication skills and implementation of the advice. The falls prevention advice might help nurses to prevent falls and increase their knowledge about falls prevention. © 2011 Blackwell Publishing Ltd.

Falls prevention in hospitals and mental health units: an extended evaluation of the FallSafe quality improvement project.

Science.gov (United States)

Healey, Frances; Lowe, Derek; Darowski, Adam; Windsor, Julie; Treml, Jonathan; Byrne, Lisa; Husk, Janet; Phipps, Jill

2014-07-01

inpatient falls are a major patient safety issue causing distress, injury and death. Systematic review suggests multifactorial assessment and intervention can reduce falls by 20-30%, but large-scale studies of implementation are few. This paper describes an extended evaluation of the FallSafe quality improvement project, which presented key components of multifactorial assessment and intervention as a care bundle. : data on delivery of falls prevention processes were collected at baseline and for 18 months from nine FallSafe units and nine control units. Data on falls were collected from local risk management systems for 24 months, and data on under-reporting through staff surveys. : in FallSafe units, delivery of seven care bundle components significantly improved; most improvements were sustained after active project support was withdrawn. Twelve-month moving average of reported fall rates showed a consistent downward trend in FallSafe units but not controls. Significant reductions in reported fall rate were found in FallSafe units (adjusted rate ratio (ARR) 0.75, 95% confidence interval (CI) 0.68-0.84 P control units (ARR 0.91, 95% CI 0.81-1.03 P = 0.13). No significant changes in injurious fall rate were found in FallSafe units (ARR 0.86, 95% CI 0.71-1.03 P = 0.11), or controls (ARR 0.88, 95% CI 0.72-1.08 P = 0.13). In FallSafe units, staff certain falls had been reported increased from 60 to 77%. : introducing evidence-based care bundles of multifactorial assessment and intervention using a quality improvement approach resulted in improved delivery of multifactorial assessment and intervention and significant reductions in fall rates, but not in injurious fall rates. © The Author 2013. Published by Oxford University Press on behalf of the British Geriatrics Society. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

The effect of polymorphism on powder compaction and dissolution properties of chemically equivalent oxytetracycline hydrochloride powders.

Science.gov (United States)

Liebenberg, W; de Villiers, M M; Wurster, D E; Swanepoel, E; Dekker, T G; Lötter, A P

1999-09-01

In South Africa, oxytetracycline is identified as an essential drug; many generic products are on the market, and many more are being developed. In this study, six oxytetracycline hydrochloride powders were obtained randomly from manufacturers, and suppliers were compared. It was found that compliance to a pharmacopoeial monograph was insufficient to ensure the optimum dissolution performance of a simple tablet formulation. Comparative physicochemical raw material analysis showed no major differences with regard to differential scanning calorimetry (DSC), infrared (IR) spectroscopy, powder dissolution, and particle size. However, the samples could be divided into two distinct types with respect to X-ray powder diffraction (XRD) and thus polymorphism. The two polymorphic forms had different dissolution properties in water or 0.1 N hydrochloride acid. This difference became substantial when the dissolution from tablets was compared. The powders containing form A were less soluble than that containing form B.

An outpatient multifactorial falls prevention intervention does not reduce falls in high-risk elderly Danes

DEFF Research Database (Denmark)

Vind, Ane B; Andersen, Hanne E; Pedersen, Kirsten D

2009-01-01

, mean age 74, 73.7%women, who had visited the emergency department or had been hospitalized due to a fall. INTERVENTION: Identification of general medical, cardiovascular, and physical risk factors for falls and individual intervention in the intervention group. Participants in the control group....... Followup exceeded 90.0%. A total of 422 falls were registered in the intervention group, 398 in the control group. Intention-to-treat analysis revealed no effect of the intervention on fall rates (relative risk=1.06, 95%confidence interval (CI)=0.75 -1.51), proportion with falls (odds ratio (OR)=1.20, 95......OBJECTIVES: To evaluate the effect of multifactorial fall prevention in community-dwelling people aged 65 and older in Denmark. DESIGN: Randomized, controlled clinical trial. SETTING: Geriatric outpatient clinic at Glostrup University Hospital. PARTICIPANTS: Three hundred ninety-two elderly people...

Electro/powder separation process

International Nuclear Information System (INIS)

Dunn, J.P.

1977-01-01

A report is presented to introduce the ELECTRO/POWDER process to the P/M Industry. The process effectively uses electrostatic forces to convey, sort, meter, and blend fine powders. The major advantages of this separating process consist of the processing of primary particles, low particle energy due to particle velocity control and the pattern of particle movement over the sieve (vertical oscillation of particles above the sieve aperture). The report briefly describes the forces involved in both mechanical and sieving devices, with major emphasis on the operating principles of this process. Sieve separation of particulates is basically the result of two physical separating processes which occur simultaneously or independently; separation (dispersion) of particulates from each other and the size separation by passage through fixed apertures. In order to accomplish this goal, mechanical sieving devices utilize various motions to induce shear forces between the sieve surface and the particulates, and between the particulates themselves. It is noted that the ELECTRO/POWDER process is making steady progress in becoming an industrial tool for sieving and feeding of fine particles. Its potential extends into both the blending and admixing of powders, either by incorporating two opposing feeders, one being charged with the opposite polarity or by modifying the ELECTRO/SIEVE to incorporate more than one input and a solid electrode to replace the sieve electrode

Investigation and hazard assessment of the 2003 and 2007 Staircase Falls rock falls, Yosemite National Park, California, USA

Directory of Open Access Journals (Sweden)

G. F. Wieczorek

2008-05-01

Full Text Available Since 1857 more than 600 rock falls, rock slides, debris slides, and debris flows have been documented in Yosemite National Park, with rock falls in Yosemite Valley representing the majority of the events. On 26 December 2003, a rock fall originating from west of Glacier Point sent approximately 200 m³ of rock debris down a series of joint-controlled ledges to the floor of Yosemite Valley. The debris impacted talus near the base of Staircase Falls, producing fragments of flying rock that struck occupied cabins in Curry Village. Several years later on 9 June 2007, and again on 26 July 2007, smaller rock falls originated from the same source area. The 26 December 2003 event coincided with a severe winter storm and was likely triggered by precipitation and/or frost wedging, but the 9 June and 26 July 2007 events lack recognizable triggering mechanisms. We investigated the geologic and hydrologic factors contributing to the Staircase Falls rock falls, including bedrock lithology, weathering, joint spacing and orientations, and hydrologic processes affecting slope stability. We improved upon previous geomorphic assessment of rock-fall hazards, based on a shadow angle approach, by using STONE, a three-dimensional rock-fall simulation computer program. STONE produced simulated rock-fall runout patterns similar to the mapped extent of the 2003 and 2007 events, allowing us to simulate potential future rock falls from the Staircase Falls detachment area. Observations of recent rock falls, mapping of rock debris, and simulations of rock fall runouts beneath the Staircase Falls detachment area suggest that rock-fall hazard zones extend farther downslope than the extent previously defined by mapped surface talus deposits.

Investigation and hazard assessment of the 2003 and 2007 Staircase Falls rock falls, Yosemite National Park, California, USA

Science.gov (United States)

Wieczorek, G. F.; Stock, G. M.; Reichenbach, P.; Snyder, J. B.; Borchers, J. W.; Godt, J. W.

2008-05-01

Since 1857 more than 600 rock falls, rock slides, debris slides, and debris flows have been documented in Yosemite National Park, with rock falls in Yosemite Valley representing the majority of the events. On 26 December 2003, a rock fall originating from west of Glacier Point sent approximately 200 m3 of rock debris down a series of joint-controlled ledges to the floor of Yosemite Valley. The debris impacted talus near the base of Staircase Falls, producing fragments of flying rock that struck occupied cabins in Curry Village. Several years later on 9 June 2007, and again on 26 July 2007, smaller rock falls originated from the same source area. The 26 December 2003 event coincided with a severe winter storm and was likely triggered by precipitation and/or frost wedging, but the 9 June and 26 July 2007 events lack recognizable triggering mechanisms. We investigated the geologic and hydrologic factors contributing to the Staircase Falls rock falls, including bedrock lithology, weathering, joint spacing and orientations, and hydrologic processes affecting slope stability. We improved upon previous geomorphic assessment of rock-fall hazards, based on a shadow angle approach, by using STONE, a three-dimensional rock-fall simulation computer program. STONE produced simulated rock-fall runout patterns similar to the mapped extent of the 2003 and 2007 events, allowing us to simulate potential future rock falls from the Staircase Falls detachment area. Observations of recent rock falls, mapping of rock debris, and simulations of rock fall runouts beneath the Staircase Falls detachment area suggest that rock-fall hazard zones extend farther downslope than the extent previously defined by mapped surface talus deposits.

Fall prevention in nursing homes

DEFF Research Database (Denmark)

Andresen, Mette; Hauge, Johnny

2014-01-01

that the number of hospitalization after a fall injury will become an even greater task for the Danish hospitals, The aim of the study was to show if there is a relationship between physically frail elderly nursing home resident’s subjective evaluation of fall-risk and an objective evaluation of their balance....... Further, to suggest tools for fall prevention in nursing home settings on the basis of the results of this study and the literature. A quantitative method inspired by the survey method was used to give an overview of fall patterns, subjective and objective evaluations of fallrisk. Participants were 16...... physically frail elderly nursing home residents from three different nursing homes. Measures: a small staff-questionnaire about incidences and places where the participants had falling-episodes during a 12 month period, The Falls Effi cacy Scale Swedish version (FES(S)) and Berg Balance Scale (BBS) Results...

Falls: epidemiology, pathophysiology, and relationship to fracture.

Science.gov (United States)

Berry, Sarah D; Miller, Ram R

2008-12-01

Falls are common in the elderly, and frequently result in injury and disability. Most falls result from an interaction between individual characteristics that increase an individual's propensity to fall and acute mediating risk factors that provide the opportunity to fall. Predisposing risk factors include age-associated changes in strength and balance, comorbidities such as osteoarthritis, visual impairment and dementia, psychotropic medications, and certain types of footwear. Fewer studies have focused on acute precipitating factors, but environmental and situational factors are clearly important to fall risk. Approximately 30% of falls result in an injury that requires medical attention, with fractures occurring in approximately 10%. In addition to the risk factors for falls, the fall descent, fall impact, and bone strength are all important determinants of whether a fall will result in a fracture. In recent years, numerous studies have been directed toward the development of effective fall and fall-related fracture prevention interventions.

Fall Risk Assessment Through Automatic Combination of Clinical Fall Risk Factors and Body-Worn Sensor Data.

Science.gov (United States)

Greene, Barry R; Redmond, Stephen J; Caulfield, Brian

2017-05-01

Falls are the leading global cause of accidental death and disability in older adults and are the most common cause of injury and hospitalization. Accurate, early identification of patients at risk of falling, could lead to timely intervention and a reduction in the incidence of fall-related injury and associated costs. We report a statistical method for fall risk assessment using standard clinical fall risk factors (N = 748). We also report a means of improving this method by automatically combining it, with a fall risk assessment algorithm based on inertial sensor data and the timed-up-and-go test. Furthermore, we provide validation data on the sensor-based fall risk assessment method using a statistically independent dataset. Results obtained using cross-validation on a sample of 292 community dwelling older adults suggest that a combined clinical and sensor-based approach yields a classification accuracy of 76.0%, compared to either 73.6% for sensor-based assessment alone, or 68.8% for clinical risk factors alone. Increasing the cohort size by adding an additional 130 subjects from a separate recruitment wave (N = 422), and applying the same model building and validation method, resulted in a decrease in classification performance (68.5% for combined classifier, 66.8% for sensor data alone, and 58.5% for clinical data alone). This suggests that heterogeneity between cohorts may be a major challenge when attempting to develop fall risk assessment algorithms which generalize well. Independent validation of the sensor-based fall risk assessment algorithm on an independent cohort of 22 community dwelling older adults yielded a classification accuracy of 72.7%. Results suggest that the present method compares well to previously reported sensor-based fall risk assessment methods in assessing falls risk. Implementation of objective fall risk assessment methods on a large scale has the potential to improve quality of care and lead to a reduction in associated hospital

Fe-based nanocrystalline powder cores with ultra-low core loss

Energy Technology Data Exchange (ETDEWEB)

Wang, Xiangyue, E-mail: wangxiangyue1986@163.com [China Iron and Steel Research Institute Group, Beijing 100081 (China); Center of Advanced Technology and Materials Co., Ltd., Beijing 100081 (China); Lu, Zhichao; Lu, Caowei; Li, Deren [China Iron and Steel Research Institute Group, Beijing 100081 (China); Center of Advanced Technology and Materials Co., Ltd., Beijing 100081 (China)

2013-12-15

Melt-spun amorphous Fe{sub 73.5}Cu{sub 1}Nb{sub 3}Si{sub 15.5}B{sub 7} alloy strip was crushed to make flake-shaped fine powders. The passivated powders by phosphoric acid were mixed with organic and inorganic binder, followed by cold compaction to form toroid-shaped bonded powder-metallurgical magnets. The powder cores were heat-treated to crystallize the amorphous structure and to control the nano-grain structure. Well-coated phosphate-oxide insulation layer on the powder surface decreased the the core loss with the insulation of each powder. FeCuNbSiB nanocrystalline alloy powder core prepared from the powder having phosphate-oxide layer exhibits a stable permeability up to high frequency range over 2 MHz. Especially, the core loss could be reduced remarkably. At the other hand, the softened inorganic binder in the annealing process could effectively improve the intensity of powder cores. - Highlights: • Fe-based nanocrystalline powder cores were prepared with low core loss. • Well-coated phosphate-oxide insulation layer on the powder surface decreased the core loss. • Fe-based nanocrystalline powder cores exhibited a stable permeability up to high frequency range over 2 MHz. • The softened inorganic binder in the annealing process could effectively improve the intensity of powder cores.

Study: control of atomic energy power plant; Etude de la regulation d'une installation atomique productrice d'energie

Energy Technology Data Exchange (ETDEWEB)

Dautray, R; Leny, J C [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1958-07-01

We are studying the control of a very flexible atomic power plant, able to supply an independent network. Two systems have been examined: in the first the moderator pre-heats the light water, in the second, this preheating is dispensed with, subsequent to a study of the dynamics of the plant. Very complete linear approximation study is being effected on the model of the second system, all effects being taken into account. The reactor is stable at all power levels, though slight reactivity or load variations cause undamped power oscillations around the equilibrium level. (author)Fren. [French] Nous etudions la regulation d'une installation atomique d'une grande souplesse, pouvant eventuellement fournir de l'energie a un reseau isole. Deux versions de l'installation sont etudiees: dans la premiere le moderateur sert a rechauffer l'eau industrielle, mais l'etude dynamique conduit a supprimer ce rechauffage, ce qui donne la deuxieme version. On effectue sur celle-ci une etude en approximation lineaire tres complete ou l'on tient compte de differents effets. L'installation se montre stable a tous les niveaux de puissance. Toutefois, de petites perturbations de reactivite ou de charge entrainent des oscillations de puissance mal amorties autour de la position d'equilibre. (auteur)

Is a fall just a fall : correlates of falling in healthy older persons. The Health, Aging and Body Composition Study

NARCIS (Netherlands)

de Rekeneire, Nathalie; Visser, Marjolein; Peila, Rita; Nevitt, Michael C; Cauley, Jane A; Tylavsky, Frances A; Simonsick, Eleanor M; Harris, Tamara B

OBJECTIVES: To identify factors associated with falling in well-functioning older people. DESIGN: Cross-sectional analyses of report of falls over the past 12 months using baseline data from the Health, Aging and Body Composition Study. SETTING: Clinic examinations in Pittsburgh, Pennsylvania, or

Preparation of superconducting powders by freeze-drying

International Nuclear Information System (INIS)

Johnson, S.M.; Gusman, M.I.; Rowcliffe, D.J.; Geballe, T.H.; Sun, J.Z.

1987-01-01

A method of preparing superconducting powders by freeze-drying is described. Powders produced by this method are homogeneous, have high purities, and are very reactive. Materials sintered from these powders have densities up to 89% of the theoretical density, and exhibit very sharp resistivity drops and large Meissner effects. The microstructure of the materials is very sensitive to the sintering temperature

Food powders flowability characterization: theory, methods, and applications.

Science.gov (United States)

Juliano, Pablo; Barbosa-Cánovas, Gustavo V

2010-01-01

Characterization of food powders flowability is required for predicting powder flow from hoppers in small-scale systems such as vending machines or at the industrial scale from storage silos or bins dispensing into powder mixing systems or packaging machines. This review covers conventional and new methods used to measure flowability in food powders. The method developed by Jenike (1964) for determining hopper outlet diameter and hopper angle has become a standard for the design of bins and is regarded as a standard method to characterize flowability. Moreover, there are a number of shear cells that can be used to determine failure properties defined by Jenike's theory. Other classic methods (compression, angle of repose) and nonconventional methods (Hall flowmeter, Johanson Indicizer, Hosokawa powder tester, tensile strength tester, powder rheometer), used mainly for the characterization of food powder cohesiveness, are described. The effect of some factors preventing flow, such as water content, temperature, time consolidation, particle composition and size distribution, is summarized for the characterization of specific food powders with conventional and other methods. Whereas time-consuming standard methods established for hopper design provide flow properties, there is yet little comparative evidence demonstrating that other rapid methods may provide similar flow prediction.

Exploring Oven-drying Technique in Producing Pineapple Powder

Directory of Open Access Journals (Sweden)

Cyril John A. Domingo

2017-11-01

Full Text Available Pineapple puree and juice of 11 to 12 °Brix were used to obtain pineapple powder using oven-drying technique. Addition of maltodextrin in treatments 2 and 4 yielded good quality powder, however addition of sugar and maltodextrin in treatments 1 and 3 resulted to sticky product which was processed to pineapple leather. Treatment 2 composed of pineapple puree and maltodextrin resulted to significantly higher powder recovery compared with treatment 4 which composed of pineapple juice and maltodextrin. The solubility of pineapple powder improved as maltodextrin concentration is increased from 40.00 % to 60.00 %.Addition of maltodextrin also reduced stickiness of the final product. An instant pineapple powder of 5.47 and 5.33 % moisture content could be produced by oven-drying.This level of moisture content will prohibit bacterial growth in the pineapple powder but may have mold or yeast growth with increase storage period at environments with high humidity. Molds were observed on the 17th day at 89.00 % relative humidity as exhibited by the moisture sorption isotherm data. This suggests that appropriate packaging with moisture barrier is recommended for pineapple powder. This study showedthat by using appropriate ratio of juice, puree, and maltodextrin and appropriate oven drying conditions, a good oven-dried pineapple powder could be obtained.

The Association Between Body Adiposity Measures, Postural Balance, Fear of Falling, and Fall Risk in Older Community-Dwelling Women.

Science.gov (United States)

Neri, Silvia Gonçalves Ricci; Gadelha, André Bonadias; de David, Ana Cristina; Ferreira, Aparecido Pimentel; Safons, Marisete Peralta; Tiedemann, Anne; Lima, Ricardo M

2017-12-07

Recent investigations demonstrate an association between obesity and the propensity of older adults to fall. The aim of this study was to investigate the association between body adiposity measures, postural balance, fear of falling, and risk of falls in older women. One hundred forty-seven volunteers took part in this cross-sectional study. Participants underwent body composition assessment using dual-energy x-ray absorptiometry and had body mass index, waist circumference (WC), and body adiposity index measured. Postural balance was assessed using a force platform, while fear of falling and risk of falls were, respectively, evaluated by the Falls Efficacy Scale-International and the QuickScreen Clinical Falls Risk Assessment. All adiposity measures were correlated to at least 1 postural stability parameter and to fear of falling (ρ= 0.163, P risk of falls (ρ= 0.325; P falling (28.04 vs 24.59; P = .002) and had a higher proportion of individuals with increased fall risk (72% vs 35%; P risk of falls in older women, which might be mediated by reduced postural balance and increased fear of falling. Among these indices, WC, an easy and low-cost assessment, demonstrated the strongest association with falls-related outcomes.

[Falls of older individuals: medical assessment].

Science.gov (United States)

De Breucker, S; Nkodo Mekongo, Y P; Ibebeke, B; Pepersack, T

2007-01-01

Falls are one of the most common problems that threaten the independence of older individuals. They usually occur when impairments in multiple domains compromise the compensatory ability of the individual, as is the case for many geriatric syndromes. A number of the physical conditions and environmental situations predispose to falls. The medical risk factors of falls are reviewed. Falls in older individuals are rarely due to a single cause. Mechanisms that maintain postural stability are altered with aging (balance, gait speed, cardiovascular function). Female gender, past history of a fall, cognitive impairment, lower extremity weakness, balance problems, psychotropic drug use, arthritis, history of stroke, orthostatic hypotension, dizziness, and anemia represent the most frequent causes of risk of falls. Physical examination should focus upon the above mentioned risk factors and also on the presence of orthostatic hypotension, visual acuity, hearing assessment, examination of the extremities for deformities or neuropathies, and carotid sinus hypersensitivity which contributes to falls in people with unexplained falls. In conclusion, assessment of older individual at risk of falls or who fall present medical specificities. However, these latter specificities should be included in a comprehensive assessment which focus on intrinsic and extrinsic factors. Interventional strategies including comprehensive and interdisciplinary assessment lead to effective prevention.

Ternary ceramic thermal spraying powder and method of manufacturing thermal sprayed coating using said powder

Energy Technology Data Exchange (ETDEWEB)

Vogli, Evelina; Sherman, Andrew J.; Glasgow, Curtis P.

2018-02-06

The invention describes a method for producing ternary and binary ceramic powders and their thermal spraying capable of manufacturing thermal sprayed coatings with superior properties. Powder contain at least 30% by weight ternary ceramic, at least 20% by weight binary molybdenum borides, at least one of the binary borides of Cr, Fe, Ni, W and Co and a maximum of 10% by weight of nano and submicro-sized boron nitride. The primary crystal phase of the manufactured thermal sprayed coatings from these powders is a ternary ceramic, while the secondary phases are binary ceramics. The coatings have extremely high resistance against corrosion of molten metal, extremely thermal shock resistance and superior tribological properties at low and at high temperatures.

The quantitative characterization of sintering of urania powders

International Nuclear Information System (INIS)

Das, P.; Kulkarni, U.D.

1981-01-01

This paper presents a unified approach towards characterization of the sintering behaviour of UO 2 powders in terms of their extrinsic properties. Empirical equations connecting the sintering index with various powder parameters have been set up. The influence of various powder parameters, either individually or as dimensionless/dimensional groups, on the sintering behaviour has been studied. The relative importance of these factors has also been analysed. A good polynomial fit has been obtained for variation of sintering index with some of the powder parameters and dimensionless/dimensional groups. The equations are expected to provide a good basis for assessing the sinterability of UO 2 powders. (Auth.)

Characterization and Sintering of Armstrong Process Titanium Powder

Science.gov (United States)

Xu, Xiaoyan; Nash, Philip; Mangabhai, Damien

2017-04-01

Titanium and titanium alloys have a high strength to weight ratio and good corrosion resistance but also need longer time and have a higher cost on machining. Powder metallurgy offers a viable approach to produce near net-shape complex components with little or no machining. The Armstrong titanium powders are produced by direct reduction of TiCl4 vapor with liquid sodium, a process which has a relatively low cost. This paper presents a systematic research on powder characterization, mechanical properties, and sintering behavior and of Armstrong process powder metallurgy, and also discusses the sodium issue, and the advantages and disadvantages of Armstrong process powders.

A Wavelet-Based Approach to Fall Detection

Directory of Open Access Journals (Sweden)

Luca Palmerini

2015-05-01

Full Text Available Falls among older people are a widely documented public health problem. Automatic fall detection has recently gained huge importance because it could allow for the immediate communication of falls to medical assistance. The aim of this work is to present a novel wavelet-based approach to fall detection, focusing on the impact phase and using a dataset of real-world falls. Since recorded falls result in a non-stationary signal, a wavelet transform was chosen to examine fall patterns. The idea is to consider the average fall pattern as the “prototype fall”.In order to detect falls, every acceleration signal can be compared to this prototype through wavelet analysis. The similarity of the recorded signal with the prototype fall is a feature that can be used in order to determine the difference between falls and daily activities. The discriminative ability of this feature is evaluated on real-world data. It outperforms other features that are commonly used in fall detection studies, with an Area Under the Curve of 0.918. This result suggests that the proposed wavelet-based feature is promising and future studies could use this feature (in combination with others considering different fall phases in order to improve the performance of fall detection algorithms.

Childhood Falls With Occipital Impacts

NARCIS (Netherlands)

Atkinson, Norrell; van Rijn, Rick R.; Starling, Suzanne P.

2017-01-01

Falls are commonly reported in children who present with both accidental and inflicted brain injuries. Short falls rarely result in serious or life-threatening injuries. Our purpose is to describe a series of cases of short falls with occipital impact leading to subdural hemorrhage (SDH). We present

Advances in beryllium powder consolidation simulations

International Nuclear Information System (INIS)

Reardon, B.J.

1998-01-01

A fuzzy logic based multiobjective genetic algorithm (GA) is introduced and the algorithm is used to optimize micromechanical densification modeling parameters for warm isopressed beryllium powder, HIPed copper powder and CIPed/sintered and HIPed tantalum powder. In addition to optimizing the main model parameters using the experimental data points as objective functions, the GA provides a quantitative measure of the sensitivity of the model to each parameter, estimates the mean particle size of the powder, and determines the smoothing factors for the transition between stage 1 and stage 2 densification. While the GA does not provide a sensitivity analysis in the strictest sense, and is highly stochastic in nature, this method is reliable and reproducible in optimizing parameters given any size data set and determining the impact on the model of slight variations in each parameter

Strain-enhanced sintering of iron powders

Energy Technology Data Exchange (ETDEWEB)

Amador, D.R.; Torralba, J.M. [Universidad Carlos III de Madrid, Departamento de Ciencias de Materiales e Ingenieria Metalurgica, Leganes, Madrid (Spain); Monge, M.A.; Pareja, R. [Universidad Carlos III de Madrid, Departamento de Fisica, Madrid (Spain)

2005-02-01

Sintering of ball-milled and un-milled Fe powders has been investigated using dilatometry, X-ray, density, and positron annihilation techniques. A considerable sintering enhancement is found in milled powders showing apparent activation energies that range between 0.44 and 0.80 eV/at. The positron annihilation results, combined with the evolution of the shrinkage rate with sintering temperature, indicate generation of lattice defects during the sintering process of milled and un-milled powders. The sintering enhancement is attributed to pipe diffusion along the core of moving dislocations in the presence of the vacancy excess produced by plastic deformation. Positron annihilation results do not reveal the presence of sintering-induced defects in un-milled powders sintered above 1200 K, the apparent activation energy being in good agreement with that for grain-boundary diffusion in {gamma}-Fe. (orig.)

Powder diffractometry

International Nuclear Information System (INIS)

Doucet, J.

1983-01-01

The new possibilities openned by the synchrotron radiation in the powder diffractometry techniques are presented. This technique is described in a general manner and some aspects which can be developed with the use of the synchrotron radiation are analyzed. (L.C.) [pt

Predicting first fall in newly diagnosed Parkinson's disease: Insights from a fall-naïve cohort.

Science.gov (United States)

Lord, Sue; Galna, Brook; Yarnall, Alison J; Coleman, Shirley; Burn, David; Rochester, Lynn

2016-12-01

Falls are common and associated with reduced independence and mortality in Parkinson's disease. Previous research has been conducted on falls-prevalent or advanced disease cohorts. This study identifies risk factors for first fall for 36 months in a newly diagnosed, falls-naïve cohort. A total of 121 consecutive Parkinson's disease patients were recruited. Falls data were collected prospectively during 36 months from diagnosis via monthly falls diaries and telephone follow-up for 117 participants. Assessment comprised a comprehensive battery of clinical, gait, and cognitive measures. Significant predictors were identified from decision-tree analysis and survival analysis with time to first fall during 36 months as the dependent variable. At baseline, 26 (22%) participants reported retrospective falls. At 36 months, the remaining cohort (n = 91) comprised 47 fallers (52%) and 30 (33%) nonfallers and 14 (15%) participants with incomplete diaries. Fallers presented with a significantly higher disease severity, poorer ability to stand on one leg, slower gait speed, increased stance time variability, and higher swing time asymmetry. Median time to first fall was 847 days. Gait speed, stance time, and Hoehn & Yahr III stage emerged as significant predictors of first fall, hazard ratio 3.44 (95% confidence interval [CI] 1.58 to 7.48), 3.31(95% CI 1.40 to 7.80), and 2.80 (95% CI 1.38 to 5.65), respectively. The hazard ratio for risk factors combined was 7.82 (CI 2.80 to 21.84). Interventions that target gait deficit and postural control in early Parkinson's disease may limit the potential for first fall. © 2016 International Parkinson and Movement Disorder Society. © 2016 International Parkinson and Movement Disorder Society.

Self-reported preclinical mobility limitation and fall history as predictors of future falls in older women: prospective cohort study

DEFF Research Database (Denmark)

Mänty, Minna Regina; Heinonen, A; Viljanen, A

2010-01-01

mobility limitation. Fall history was recalled for previous 12 months and dichotomized. The incidence of future falls over 12 months was followed up with fall calendars. RESULTS: During the fall follow-up, a total of 440 falls were reported by 201 participants. Among those with fall history, women...

Powder metallurgy techniques in nuclear technology

International Nuclear Information System (INIS)

Mardon, P.G.

1983-01-01

The nuclear application of conventional powder metallurgy routes is centred on the fabrication of ceramic fuels. The stringent demands in terms of product performance required by the nuclear industry militate against the use of conventional powder metallurgy to produce metallic components such as the fuel cladding. However, the techniques developed in powder metallurgy find widespread application throughout nuclear technology. Illustrations of the use of these techniques are given in the fields of absorber materials, ceramic cladding materials, oxide fuels, cermet fuels, and the disposal of highly active waste. (author)

Plasma metallization of refractory carbide powders

International Nuclear Information System (INIS)

Koroleva, E.B.; Klinskaya, N.A.; Rybalko, O.F.; Ugol'nikova, T.A.

1986-01-01

The effect of treatment conditions in plasma on properties of produced metallized powders of titanium, tungsten and chromium carbides with the main particle size of 40-80 μm is considered. It is shown that plasma treatment permits to produce metallized powders of carbide materials with the 40-80 μm particle size. The degree of metallization, spheroidization, chemical and phase composition of metallized carbide powders are controlled by dispersivity of the treated material, concentration of a metal component in the treated mixtures, rate of plasma flow and preliminary spheroidization procedure

Net shape powder processing of aluminium

International Nuclear Information System (INIS)

Schaffer, G.B.

2000-01-01

The increasing interest in light weight materials coupled to the need for cost-effective processing have combined to create a significant opportunity for aluminium powder metallurgy. Net shape processing of aluminium using the classical press-and-sinter powder metallurgy technique is a unique and important metal-forming method which is cost effective in producing complex parts at, or very close to, final dimensions. This paper provides an overview of the net shape powder processing of aluminium. Current research is critically reviewed and the future potential is briefly considered

Falls and Use of Assistive Devices in Stroke Patients with Hemiparesis: Association with Balance Ability and Fall Efficacy.

Science.gov (United States)

Kim, Oksoo; Kim, Jung-Hee

2015-01-01

This study investigates balance ability and the fall efficacy with regard to the experiences of stroke patients with hemiparesis. The experience of falling, the use of assistive devices, and each disease-related characteristic were assessed using face-to-face interviews and a self-reported questionnaire. The Berg Balance Scale and Fall Efficacy Scale were used to measure balance ability and confidence. The fall efficacy was significantly lower in participants who had experienced falls than those who had not. The participants who used assistive devices exhibited low balance ability and fall efficacy compared to those who did not use assistive devices. Stroke patients with fall experience and walking aids might be considered at increased risk of falling. Preventive measures for individuals using walking aids may be beneficial in reducing the fall rate of community-dwelling stroke patients. © 2014 Association of Rehabilitation Nurses.

Application of permanent magnets made from NdFeB powder and from mixtures of powders in DC motors

International Nuclear Information System (INIS)

Slusarek, B.; Dudzikowski, I.

2002-01-01

The paper presents the influence of magnetic properties of applied permanent magnets on the characteristics of DC motors excited with these magnets. In the factory-produced DC motors, excited with sintered ferrite magnets, authors replaced ferrite magnets with the dielectromagnets from NdFeB powder and from different mixtures of NdFeB and ferrite powders. The paper shows the increase of the power of the resultant DC motors according to the powders' content

Prevalence of falls in elderly women.

Science.gov (United States)

Vitor, Priscila Regina Rorato; de Oliveira, Ana Carolina Kovaleski; Kohler, Renan; Winter, Gabriele Regiane; Rodacki, Cintia; Krause, Maressa Priscila

2015-01-01

To verify prevalence of falls and fear of falling, and to compare functional fitness among elderly women fallers and non-fallers. Seventy-eight elderly women participated in this study. Cases of falls and the fear of falling were self-reported by the elderly women, while the functional fitness was measured by a set of functional tests. Mean and standard deviation were used to describe the sample. Independent t-test was used to compare functional fitness between groups. The prevalence of falls in this sample was 32.4%. Among women fallers, 40% self-reported a high fear of falling. It is recommended that functional and resistance exercises are included in the preventive strategies for reducing risk factors for falls and its determinants in elderly women. Level of Evidence II, Prognostic-Prospective Study.

Time resolved fluorescence of cow and goat milk powder

Science.gov (United States)

Brandao, Mariana P.; de Carvalho dos Anjos, Virgílio; Bell., Maria José V.

2017-01-01

Milk powder is an international dairy commodity. Goat and cow milk powders are significant sources of nutrients and the investigation of the authenticity and classification of milk powder is particularly important. The use of time-resolved fluorescence techniques to distinguish chemical composition and structure modifications could assist develop a portable and non-destructive methodology to perform milk powder classification and determine composition. This study goal is to differentiate milk powder samples from cows and goats using fluorescence lifetimes. The samples were excited at 315 nm and the fluorescence intensity decay registered at 468 nm. We observed fluorescence lifetimes of 1.5 ± 0.3, 6.4 ± 0.4 and 18.7 ± 2.5 ns for goat milk powder; and 1.7 ± 0.3, 6.9 ± 0.2 and 29.9 ± 1.6 ns for cow's milk powder. We discriminate goat and cow powder milk by analysis of variance using Fisher's method. In addition, we employed quadratic discriminant analysis to differentiate the milk samples with accuracy of 100%. Our results suggest that time-resolved fluorescence can provide a new method to the analysis of powder milk and its composition.

Slip casting nano-particle powders for making transparent ceramics

Science.gov (United States)

Kuntz, Joshua D [Livermore, CA; Soules, Thomas F [Livermore, CA; Landingham, Richard Lee [Livermore, CA; Hollingsworth, Joel P [Oakland, CA

2011-04-12

A method of making a transparent ceramic including the steps of providing nano-ceramic powders in a processed or unprocessed form, mixing the powders with de-ionized water, the step of mixing the powders with de-ionized water producing a slurry, sonifing the slurry to completely wet the powder and suspend the powder in the de-ionized water, separating very fine particles from the slurry, molding the slurry, and curing the slurry to produce the transparent ceramic.

Powder technology

International Nuclear Information System (INIS)

Agueda, Horacio

1989-01-01

Powder technology is experiencing nowadays a great development and has broad application in different fields: nuclear energy, medicine, new energy sources, industrial and home artifacts, etc. Ceramic materials are of daily use as tableware and also in the building industry (bricks, tiles, etc.). However, in machine construction its utilization is not so common. The same happens with metals: powder metallurgy is employed less than traditional metal forming techniques. Both cases deal with powder technology and the forming techniques as far as the final consolidation through sintering processes are very similar. There are many different methods and techniques in the forming stage: cold-pressing, slip casting, injection molding, extrusion molding, isostatic pressing, hot-pressing (which involves also the final consolidation step), etc. This variety allows to obtain almost any desired form no matter how complex it could be. Some applications are very specific as in the case of UO 2 pellets (used as nuclear fuels) but with the same technique and other materials, it is possible to manufacture a great number of different products. This work shows the characteristics and behaviour of two magnetic ceramic materials (ferrites) fabricated in the laboratory of the Applied Research Division of the Bariloche Atomic Center for different purposes. Other materials and products made with the same method are also mentioned. Likewise, densities and shrinkage obtained by different methods of forming (cold-pressing, injection molding, slip casting and extrusion molding) using high-purity alumina (99.5% Al 2 O 3 ). Finally, different applications of such methods are given. (Author) [es

Investigation of pressing of molybdenum powder compacts

International Nuclear Information System (INIS)

Mymrin, S.A.; Kuznetsov, V.Eh.; Yampol'skij, M.L.; Leonov, S.A.; Mikhridinov, R.M.; Korzukhin, V.A.

1990-01-01

Results of an experimental investigation into pressing of compacts of MCh type molybdenum powders using the industrial equipment are presented. To measure the density of powder molybdenum billets a radioisotopic density meter with cesium-137 is used as radioactive gamma radiation source. The dependence of the produced billet density on the specific compacting pressure at different values of the powder bulk density is ascertained

Cryomilling of Thermoplastic Powder for Prepreg Applications

Science.gov (United States)

2013-09-01

Cryomilling of Thermoplastic Powder for Prepreg Applications by Brian Parquette, Anit Giri, Daniel J. O’Brien, Sarah Brennan, Kyu Cho, and...MD 21005-5066 ARL-TR-6591 September 2013 Cryomilling of Thermoplastic Powder for Prepreg Applications Brian Parquette and Sarah Brennan...COVERED (From - To) 1 March 2012–30 May 2013 4. TITLE AND SUBTITLE Cryomilling of Thermoplastic Powder for Prepreg Applications 5a. CONTRACT

Ageing vision and falls: a review.

Science.gov (United States)

Saftari, Liana Nafisa; Kwon, Oh-Sang

2018-04-23

Falls are the leading cause of accidental injury and death among older adults. One of three adults over the age of 65 years falls annually. As the size of elderly population increases, falls become a major concern for public health and there is a pressing need to understand the causes of falls thoroughly. While it is well documented that visual functions such as visual acuity, contrast sensitivity, and stereo acuity are correlated with fall risks, little attention has been paid to the relationship between falls and the ability of the visual system to perceive motion in the environment. The omission of visual motion perception in the literature is a critical gap because it is an essential function in maintaining balance. In the present article, we first review existing studies regarding visual risk factors for falls and the effect of ageing vision on falls. We then present a group of phenomena such as vection and sensory reweighting that provide information on how visual motion signals are used to maintain balance. We suggest that the current list of visual risk factors for falls should be elaborated by taking into account the relationship between visual motion perception and balance control.

Cerebroprotective Actions of Triticum aestivum Linn Powder and Bauhinia purpurea Flower Powder in Surgically Induced Cerebral Infraction in Rats.

Science.gov (United States)

Annapurna, Akula; Vishala, Thonangi C; Bitra, Veera R; Rapaka, Deepthi; Shaik, Asmath

2018-01-01

The prime objective of this study is to evaluate the cerebroprotective actions of Triticum aestivum (wheatgrass) powder and Bauhinia purpurea flower (dev kanchan) powder against the experimentally induced global ischemia reperfusion injury in rats. In the first phase of the studies, 1 h before the surgical procedure, the Wistar rats were orally served with varied doses of wheatgrass powder (5, 10, 30, and 100 μg/kg) and Bauhinia flower powder (30, 100, 200, and 300 μg/kg), respectively. The ischemia was induced by 30-min bilateral carotid artery occlusion in succession to reperfusion for 4 h. It was proved that the wheatgrass powder and Bauhinia flower powder yielded a significant, dose-dependent cerebroprotection in terms of reduction in cerebral infarct size when compared with the control group. Coming to the second phase of the studies, a certain potential dose of 10 μg/kg of wheatgrass and 200 μg/kg of Bauhinia flower powders was selected keeping the protective action in view, and the animals were treated for 15 days. The major findings of the study are that wheatgrass and Bauhinia flower powders significantly augmented the magnitude of the antioxidant enzymes, viz., super oxide dismutase and catalase, and further reduced the levels of lipid peroxidation. The present study clearly showed that the wheatgrass powder and Bauhinia flower powder possess significant antioxidant properties that may act as a key ingredient in various ayurvedic preparations for the treatment of various diseases like cerebral ischemic reperfusion injury. The wheat grass contains high amount of bioflavonoids, alkaloids, SOD etc which are responsible for anti oxidant activity.The Bauhinia purpurea contains glycosides, flavonoids and also plays a major role in DPPH activity which is responsible for anti oxidant activity.The wheat grass (10 mg/kg) and bauhinia (200 mg/kg) significantly(P bauhinia (200 mg/kg) significantly (P <0.0001) reduced the lipid peroxidation (MDA) and increased SOD

Characteristics of daily life gait in fall and non fall-prone stroke survivors and controls

NARCIS (Netherlands)

Mirjam Pijnappels; Sjoerd M. Bruijn; Kimberley M. Schooten; Jaap H. van Dieën; Dr. H.M. Wittink; Michiel Punt

2016-01-01

Background: Falls in stroke survivors can lead to serious injuries and medical costs. Fall risk in older adults can be predicted based on gait characteristics measured in daily life. Given the different gait patterns that stroke survivors exhibit it is unclear whether a similar fall-prediction model

Free radical interactions between raw materials in dry soup powder.

Science.gov (United States)

Raitio, Riikka; Orlien, Vibeke; Skibsted, Leif H

2011-12-01

Interactions at the free radical level were observed between dry ingredients in cauliflower soup powder, prepared by dry mixing of ingredients and rapeseed oil, which may be of importance for quality deterioration of such dry food products. The free radical concentrations of cauliflower soup powder, obtained by electron spin resonance (ESR) spectroscopy, rapidly become smaller during storage (40°C and relative humidity of 75%) than the calculated concentrations of free radicals based on the free radical concentrations of the powder ingredients used to make the soup powder and stored separately under similar conditions. Similarly, free radical concentrations decreased faster when any combination of two powder ingredients (of the three major ingredients of the soup powder) were mixed together and stored at 50°C for 1week than when each powder component was stored separately. Furthermore, yeast extract powder was found to play a key role when free radical interactions between powder ingredients occurred. The incubation of rapeseed oil with powder ingredients at 45°C for 24h, indicated the ability of cauliflower powder to increase the concentration of hydroperoxides in rapeseed oil, while yeast extract powder was found to prevent this hydroperoxide formation. Copyright © 2011 Elsevier Ltd. All rights reserved.

Characteristics and adaptive strategies linked with falls in stroke survivors from analysis of laboratory-induced falls

Science.gov (United States)

Honeycutt, Claire F.; Nevisipour, Masood; Grabiner, Mark D.

2016-01-01

Falls are the most common and expensive medical complication in stroke survivors. There is remarkably little information about what factors lead to a fall in stroke survivors. With few exceptions, the falls literature in stroke has focused on relating metrics of static balance and impairment to fall outcomes in the acute care setting or in community. While informative, these studies provide little information about what specific impairments in a stroke-survivor’s response to dynamic balance challenges lead to a fall. We identified the key kinematic characteristics of stroke survivors’ stepping responses following a balance disturbance that are associated with a fall following dynamic balance challenges. Stroke survivors were exposed to posteriorly-directed translations of a treadmill belt that elicited a stepping response. Kinematics were compared between successful and failed recovery attempts (i.e. a fall). We found that the ability to arrest and reverse trunk flexion and the ability to perform an appropriate initial compensatory step were the most critical response contributors to a successful recovery. We also identified 2 compensatory strategies utilized by stroke survivors to avoid a fall. Despite significant post-stroke functional impairments, the biomechanical causes of trip-related falls by stroke survivors appear to be similar to those of unimpaired older adults and lower extremity amputees. However, compensatory strategies (pivot, hopping) were observed. PMID:27614614

Characterization of Metal Powders Used for Additive Manufacturing.

Science.gov (United States)

Slotwinski, J A; Garboczi, E J; Stutzman, P E; Ferraris, C F; Watson, S S; Peltz, M A

2014-01-01

Additive manufacturing (AM) techniques can produce complex, high-value metal parts, with potential applications as critical parts, such as those found in aerospace components. The production of AM parts with consistent and predictable properties requires input materials (e.g., metal powders) with known and repeatable characteristics, which in turn requires standardized measurement methods for powder properties. First, based on our previous work, we assess the applicability of current standardized methods for powder characterization for metal AM powders. Then we present the results of systematic studies carried out on two different powder materials used for additive manufacturing: stainless steel and cobalt-chrome. The characterization of these powders is important in NIST efforts to develop appropriate measurements and standards for additive materials and to document the property of powders used in a NIST-led additive manufacturing material round robin. An extensive array of characterization techniques was applied to these two powders, in both virgin and recycled states. The physical techniques included laser diffraction particle size analysis, X-ray computed tomography for size and shape analysis, and optical and scanning electron microscopy. Techniques sensitive to structure and chemistry, including X-ray diffraction, energy dispersive analytical X-ray analysis using the X-rays generated during scanning electron microscopy, and X-Ray photoelectron spectroscopy were also employed. The results of these analyses show how virgin powder changes after being exposed to and recycled from one or more Direct Metal Laser Sintering (DMLS) additive manufacturing build cycles. In addition, these findings can give insight into the actual additive manufacturing process.

Characterization of Metal Powders Used for Additive Manufacturing

Science.gov (United States)

Slotwinski, JA; Garboczi, EJ; Stutzman, PE; Ferraris, CF; Watson, SS; Peltz, MA

2014-01-01

Additive manufacturing (AM) techniques1 can produce complex, high-value metal parts, with potential applications as critical parts, such as those found in aerospace components. The production of AM parts with consistent and predictable properties requires input materials (e.g., metal powders) with known and repeatable characteristics, which in turn requires standardized measurement methods for powder properties. First, based on our previous work, we assess the applicability of current standardized methods for powder characterization for metal AM powders. Then we present the results of systematic studies carried out on two different powder materials used for additive manufacturing: stainless steel and cobalt-chrome. The characterization of these powders is important in NIST efforts to develop appropriate measurements and standards for additive materials and to document the property of powders used in a NIST-led additive manufacturing material round robin. An extensive array of characterization techniques was applied to these two powders, in both virgin and recycled states. The physical techniques included laser diffraction particle size analysis, X-ray computed tomography for size and shape analysis, and optical and scanning electron microscopy. Techniques sensitive to structure and chemistry, including X-ray diffraction, energy dispersive analytical X-ray analysis using the X-rays generated during scanning electron microscopy, and X-Ray photoelectron spectroscopy were also employed. The results of these analyses show how virgin powder changes after being exposed to and recycled from one or more Direct Metal Laser Sintering (DMLS) additive manufacturing build cycles. In addition, these findings can give insight into the actual additive manufacturing process. PMID:26601040

Falls and comorbidity

DEFF Research Database (Denmark)

Jørgensen, Terese Sara Høj; Hansen, Annette Højmann; Sahlberg, Marie

2014-01-01

AIMS: To compare nationwide time trends and mortality in hip and proximal humeral fractures; to explore associations between incidences of falls risk related comorbidities (FRICs) and incidence of fractures. METHODS: The study is a retrospective cohort study using nationwide Danish administrative....... CONCLUSIONS: The results suggest that the overall reduction in fractures can be explained by reduction in falls related comorbidity....

Home Improvements Prevent Falls

Science.gov (United States)

... turn JavaScript on. Feature: Falls and Older Adults Home Improvements Prevent Falls Past Issues / Winter 2014 Table ... and ensure your safety. "Safe-ty-fy" Your Home Some Questions for Your Provider Will my medicines ...

Some aspects of UO{sub 2} powder production

Energy Technology Data Exchange (ETDEWEB)

Balakrishna, P; Asnani, C K; Prabhakar Rao, L; Kartha, R M; Pillai, P K.M. [Nuclear Fuel Complex, Hyderabad (India)

1994-06-01

UO{sub 2} powder is being produced in a chemical plant from enriched UF{sub 6} and supplied to the pelletizing plant. Small quantities of scrap UO{sub 2} received back from the pelletizing plant are also recycled in the chemical plant to produce UO{sub 2} powder. The powder should be of a consistently high quality so as to finally yield high density sintered pellets with minimum rejection. The final yield of acceptable finished pellets depends on the quality of the powder in the chemical plant as well as the quality of pressing in the pelletizing plant. In this paper, some examples of measures adopted for achieving good quality powder production are presented. (author). 9 refs., 2 figs.

Introduction to powder metallurgy processes for titanium manufacturing

International Nuclear Information System (INIS)

Esteban, P. G.; Bolzoni, L.; Ruiz-Navas, E. M.; Gordo, E.

2011-01-01

The development of new extraction processes to produce titanium in powder form leads Powder Metallurgy to an advantage position among the manufacturing processes for titanium. The cost reduction of base material, coupled with the economy of the powder metallurgy processes, give titanium industry the chance to diversify its products, which could lead to production volumes able to stabilise the price of the metal. This work reviews some of the Powder Metallurgy techniques for the manufacturing of titanium parts, and describes the two typical approaches for titanium manufacturing: Blending Elemental and Prealloyed Powders. Among others, conventional pressing and sintering are described, which are compared with cold and hot isostatic pressing techniques. Real and potential applications are described. (Author) 71 refs.

Ambulatory fall-risk assessment: amount and quality of daily-life gait predict falls in older adults.

Science.gov (United States)

van Schooten, Kimberley S; Pijnappels, Mirjam; Rispens, Sietse M; Elders, Petra J M; Lips, Paul; van Dieën, Jaap H

2015-05-01

Ambulatory measurements of trunk accelerations can provide valuable information on the amount and quality of daily-life activities and contribute to the identification of individuals at risk of falls. We compared associations between retrospective and prospective falls with potential risk factors as measured by daily-life accelerometry. In addition, we investigated predictive value of these parameters for 6-month prospective falls. One week of trunk accelerometry (DynaPort MoveMonitor) was obtained in 169 older adults (mean age 75). The amount of daily activity and quality of gait were determined and validated questionnaires on fall-risk factors, grip strength, and trail making test were obtained. Six-month fall incidence was obtained retrospectively by recall and prospectively by fall diaries and monthly telephone contact. Among all participants, 35.5% had a history of ≥1 falls and 34.9% experienced ≥1 falls during 6-month follow-up. Logistic regressions showed that questionnaires, grip strength, and trail making test, as well as the amount and quality of gait, were significantly associated with falls. Significant associations differed between retrospective and prospective analyses although odds ratios indicated similar patterns. Predictive ability based on questionnaires, grip strength, and trail making test (area under the curve .68) improved substantially by accelerometry-derived parameters of the amount of gait (number of strides), gait quality (complexity, intensity, and smoothness), and their interactions (area under the curve .82). Daily-life accelerometry contributes substantially to the identification of individuals at risk of falls, and can predict falls in 6 months with good accuracy. © The Author 2015. 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.

Fall Prevention in a Primary Care Setting.

Science.gov (United States)

Siegrist, Monika; Freiberger, Ellen; Geilhof, Barbara; Salb, Johannes; Hentschke, Christian; Landendoerfer, Peter; Linde, Klause; Halle, Martin; Blank, Wolfgang A

2016-05-27

Falls and fall-related injuries are common in community-dwelling elderly people. Effective multifactorial fall prevention programs in the primary care setting may be a promising approach to reduce the incidence rate of falls. In a cluster randomized trial in 33 general practices 378 people living independently and at high risk of falling (65 to 94 years old; 285 women) were allocated to either a 16 week exercise-based fall prevention program including muscle strengthening and challenging balance training exercises, combined with a 12 week home-based exercise program (222 participants), or to usual care (156 participants). The main outcome was number of falls over a period of 12 months. Secondary outcomes were the number of fall-related injuries, physical function (Timed-Up-and-Go-Test, TUG, Chair-Stand-Test, CST, modified Romberg Test), and fear of falling. In the intervention group (n=222 patients in 17 general practices) 291 falls occurred, compared to 367 falls in the usual care group (n=156 patients in 16 general practices). We observed a lower incidence rate for falls in the intervention group (incidence rate ratio/IRR: 0.54; 95% confidence interval (CI): [0.35; 0.84], p=0.007) and for fall-related injuries (IRR: 0.66; [0.42; 0.94], p=0.033). Additionally, patients in the intervention group showed significant improvements in secondary endpoints (TUG: -2.39 s, [-3.91; -0.87], p=0.014; mRomberg: 1.70 s, [0.35; 3.04], p=0.037; fear of falling: -2.28 points, [-3.87; -0.69], p=0.022) compared to usual care. A complex falls prevention program in a primary care setting was effective in reducing falls and fall-related injuries in community dwelling older adults at risk.

Factors influencing short-term outcomes for older patients accessing emergency departments after a fall: The role of fall dynamics.

Science.gov (United States)

Trevisan, Caterina; Di Gregorio, Patrizia; Debiasi, Eugenio; Pedrotti, Martina; La Guardia, Mario; Manzato, Enzo; Sergi, Giuseppe; March, Albert

2017-10-01

While the relevance of falls in raising the risk of fractures, hospitalization and disability in older age is well recognized, the factors influencing the onset of fractures and the need for ward admission after a fall have yet to be fully elucidated. We investigated which factors and fall dynamics were mainly associated with fall-related injuries and hospitalization among elderly persons accessing the Emergency Department (ED) following a fall. The study involved 2144 older subjects who accessed the ED after a fall. Data on the fall´s nature and related injuries, ward admissions, history of falls, dementia, and medical therapies were examined for all patients. Considering dynamics, we distinguished accidental falls (due to interaction with environmental hazards while in motion) and falls from standing (secondary to syncope, lipothymia, drop attack, or vertigo). The overall prevalence of fractures in our population did not differ significantly with advancing age, though hip fractures were more common in the oldest, and upper limb fractures in the youngest patients. Falls from standing were associated with polypharmacy and with higher ward admission rate despite a lower fractures´ prevalence than accidental falls. The chances of fall-related fractures were more than fourfold as high for accidental dynamics (OR=4.05, 95%CI:3.10-5.29, pfall-related fractures (OR=6.84, 95%CI:5.45-8.58, pfall dynamics. Outcomes of falls in older age depend not only on any fall-related injuries, but also on factors such as polypharmacy, cognitive status and fall dynamics. Copyright © 2017 Elsevier B.V. All rights reserved.

Fall prevention in central coast community pharmacies.

Science.gov (United States)

Stuart, Gina M; Kale, Helen L

2018-04-19

Fall injuries among people aged 65 years and over (older people) cause substantial health decline and cost to the health system. In 2009 in New South Wales, 25.6% of older people fell in the previous year, and 10.7% (32 000) were hospitalised. Pharmacists are trusted professionals, who interact extensively with older people and have potential to augment fall prevention in pharmacies. This brief report describes how professional development improved pharmacist's knowledge and confidence in fall prevention, encouraged implementation of fall prevention plans and facilitated the provision of brief fall prevention interventions for older clients, after identification of fall risk. In 2014, pharmacists from all Central Coast pharmacies (n = 76) were invited to free, continuing professional development (CPD) in fall prevention. It provided education and resources to identify clients' fall risk, conduct brief fall prevention interventions and implement fall prevention health promotion plans (FPHPP). Pharmacists completed written: Baseline and post-workshop questionnaires to assess changes in pharmacist's knowledge and confidence, and existing fall prevention in pharmacies. Logs of client fall risk and brief fall prevention interventions offered to clients. Four-month follow-up questionnaires to assess implementation of FPHPPs and pharmacy practice changes. Pharmacists representing 36% of pharmacies participated. At four-month follow-up, 67% had implemented FPHPPs, and 62% delivered brief interventions determined by client fall risk. Fall prevention in pharmacies can be augmented through locally provided CPD tailored for pharmacists. SO WHAT?: This model could increase fall prevention reach. It is transferable to settings where health professionals provide services to older adults and require reregistration through professional development. © 2018 Australian Health Promotion Association.

Characterization of powdered fish heads for bone graft biomaterial applications.

Science.gov (United States)

Oteyaka, Mustafa Ozgür; Unal, Hasan Hüseyin; Bilici, Namık; Taşçı, Eda

2013-01-01

The aim of this study was to define the chemical composition, morphology and crystallography of powdered fish heads of the species Argyrosomus regius for bone graft biomaterial applications. Two sizes of powder were prepared by different grinding methods; Powder A (coarse, d50=68.5 µm) and Powder B (fine, d50=19.1 µm). Samples were analyzed using X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM), thermogravimetry (TG), and energy dispersive X-ray spectroscopy (EDS). The powder was mainly composed of aragonite (CaCO3) and calcite (CaCO3). The XRD pattern of Powder A and B matched standard aragonite and calcite patterns. In addition, the calcium oxide (CaO) phase was found after the calcination of Powder A. Thermogravimetry analysis confirmed total mass losses of 43.6% and 47.3% in Powders A and B, respectively. The microstructure of Powder A was mainly composed of different sizes and tubular shape, whereas Powder B showed agglomerated particles. The high quantity of CaO and other oxides resemble the chemical composition of bone. In general, the powder can be considered as bone graft after transformation to hydroxyapatite phase.

Compaction of amorphous iron–boron powder

DEFF Research Database (Denmark)

Hendriksen, Peter Vang; Mørup, Steen; Koch, Christian

1993-01-01

Large scale practical use of bulk amorphous alloys requires the capability of molding the material to a desired design, for instance by compaction of an amorphous powder. This is a difficult task because the sintering temperature is limited by the crystallization temperature of the alloy.1 Here we......, should facilitate a compaction. The passivation layer, however, impedes a compaction. Isostatic pressing at 540 K at a pressure of 200 MPa clearly illustrated this; pellets pressed from passivated powder were much more brittle than pellets pressed from unpassivated powder. The density of the pellets...... was very low ([approximately-equal-to]25% of the density of bulk FeB). We have designed a die for uniaxial pressing in which the compaction can be performed without exposing the powder to air and have obtained densities larger than 60% of that of bulk FeB. We have reported studies of the dependence...

[Effects of a fall prevention program on falls in frail elders living at home in rural communities].

Science.gov (United States)

Yoo, Jae-Soon; Jeon, Mi Yang; Kim, Chul-Gyu

2013-10-01

This study was conducted to determine the effects of a fall prevention program on falls, physical function, psychological function, and home environmental safety in frail elders living at home in rural communities. The design of this study was a nonequivalent control group pre posttest design. The study was conducted from July to November, 2012 with 30 participants in the experimental group and 30 in the control group. Participants were registered at the public health center of E County. The prevention program on falls consisted of laughter therapy, exercise, foot care and education. The program was provided once a week for 8 weeks and each session lasted 80 minutes. The risk score for falls and depression in the experimental group decreased significantly compared with scores for the control group. Compliance with prevention behavior related to falls, knowledge score on falls, safety scores of home environment, physical balance, muscle strength of lower extremities, and self-efficacy for fall prevention significantly increased in the experimental group compared with the control group. These results suggest that the prevention program on falls is effective for the prevention of falls in frail elders living at home.

Fall prevention in the elderly

Science.gov (United States)

Ungar, Andrea; Rafanelli, Martina; Iacomelli, Iacopo; Brunetti, Maria Angela; Ceccofiglio, Alice; Tesi, Francesca; Marchionni, Niccolò

2013-01-01

Summary Falls are frequent in the elderly and affect mortality, morbidity, loss of functional capacity and institutionalization. In the older patient the incidence of falls can sometimes be underestimated, even in the absence of a clear cognitive impairment, because it is often difficult to reconstruct the dynamics. It is quite common that forms due to syncope are associated with retrograde amnesia and in 40 to 60% of the cases falls happen in the absence of witnesses. The pathogenesis of falls is often multifactorial, due to physiological age-related changes or more properly pathological factors, or due to the environment. The identification of risk factors is essential in the planning of preventive measures. Syncope is one of major causes of falls. About 20% of cardiovascular syncope in patients older than 70 appears as a fall and more than 20% of older people with Carotid Sinus Syndrome complain of falls as well as syncope. These data clearly state that older patients with history of falls should undergo a cardiovascular and neuroautonomic assessment besides the survey of other risk factors. Multifactorial assessment requires a synergy of various specialists. The geriatrician coordinates the multidisciplinary intervention in order to make the most effective evaluation of the risk of falling, searching for all predisposing factors, aiming towards a program of prevention. In clear pathological conditions it is possible to enact a specific treatment. Particular attention must indeed be paid to the re-evaluation of drug therapy, with dose adjustments or withdrawal especially for antihypertensive, diuretics and benzodiazepines. The Guidelines of the American Geriatrics Society recommend modification of environmental hazards, training paths, hip protectors and appropriate use of support tools (sticks, walkers), which can be effective elements of a multifactorial intervention program. Balance exercises are also recommended. In conclusion, an initial assessment

Fall prevention in the elderly.

Science.gov (United States)

Ungar, Andrea; Rafanelli, Martina; Iacomelli, Iacopo; Brunetti, Maria Angela; Ceccofiglio, Alice; Tesi, Francesca; Marchionni, Niccolò

2013-05-01

Falls are frequent in the elderly and affect mortality, morbidity, loss of functional capacity and institutionalization. In the older patient the incidence of falls can sometimes be underestimated, even in the absence of a clear cognitive impairment, because it is often difficult to reconstruct the dynamics. It is quite common that forms due to syncope are associated with retrograde amnesia and in 40 to 60% of the cases falls happen in the absence of witnesses. The pathogenesis of falls is often multifactorial, due to physiological age-related changes or more properly pathological factors, or due to the environment. The identification of risk factors is essential in the planning of preventive measures. Syncope is one of major causes of falls. About 20% of cardiovascular syncope in patients older than 70 appears as a fall and more than 20% of older people with Carotid Sinus Syndrome complain of falls as well as syncope. These data clearly state that older patients with history of falls should undergo a cardiovascular and neuroautonomic assessment besides the survey of other risk factors. Multifactorial assessment requires a synergy of various specialists. The geriatrician coordinates the multidisciplinary intervention in order to make the most effective evaluation of the risk of falling, searching for all predisposing factors, aiming towards a program of prevention. In clear pathological conditions it is possible to enact a specific treatment. Particular attention must indeed be paid to the re-evaluation of drug therapy, with dose adjustments or withdrawal especially for antihypertensive, diuretics and benzodiazepines. The Guidelines of the American Geriatrics Society recommend modification of environmental hazards, training paths, hip protectors and appropriate use of support tools (sticks, walkers), which can be effective elements of a multifactorial intervention program. Balance exercises are also recommended. In conclusion, an initial assessment, supported by a

Sun drying of residual annatto seed powder

Directory of Open Access Journals (Sweden)

Dyego da Costa Santos

2015-01-01

Full Text Available Residual annatto seeds are waste from bixin extraction in the food, pharmaceutical and cosmetic industries. Most of this by-product is currently discarded; however, the use of these seeds in human foods through the elaboration of powder added to other commercial powders is seen as a viable option. This study aimed at drying of residual annatto powder, with and without the oil layer derived from the industrial extraction of bixin, fitting different mathematical models to experimental data and calculating the effective moisture diffusivity of the samples. Powder containing oil exhibited the shortest drying time, highest drying rate (≈ 5.0 kg kg-1 min-1 and highest effective diffusivity (6.49 × 10-12 m2 s-1. All mathematical models assessed were a suitable representation of the drying kinetics of powders with and without oil, with R2 above 0.99 and root mean square error values lower than 1.0.

Fall-Prone Older People's Attitudes towards the Use of Virtual Reality Technology for Fall Prevention.

Science.gov (United States)

Dockx, Kim; Alcock, Lisa; Bekkers, Esther; Ginis, Pieter; Reelick, Miriam; Pelosin, Elisa; Lagravinese, Giovanna; Hausdorff, Jeffrey M; Mirelman, Anat; Rochester, Lynn; Nieuwboer, Alice

2017-01-01

Virtual reality (VR) technology is a relatively new rehabilitation tool that can deliver a combination of cognitive and motor training for fall prevention. The attitudes of older people to such training are currently unclear. This study aimed to investigate: (1) the attitudes of fall-prone older people towards fall prevention exercise with and without VR; (2) attitudinal changes after intervention with and without VR; and (3) user satisfaction following fall prevention exercise with and without VR. A total of 281 fall-prone older people were randomly assigned to an experimental group receiving treadmill training augmented by VR (TT+VR, n = 144) or a control group receiving treadmill training alone (TT, n = 137). Two questionnaires were used to measure (1) attitudes towards fall prevention exercise with and without VR (AQ); and (2) user satisfaction (USQ). AQ was evaluated at baseline and after intervention. USQ was measured after intervention only. The AQ revealed that most participants had positive attitudes towards fall prevention exercise at baseline (82.2%) and after intervention (80.6%; p = 0.144). In contrast, only 53.6% were enthusiastic about fall prevention exercise with VR at baseline. These attitudes positively changed after intervention (83.1%; p < 0.001), and 99.2% indicated that they enjoyed TT+VR. Correlation analyses showed that postintervention attitudes were strongly related to user satisfaction (USQ: r = 0.503; p < 0.001). Older people's attitudes towards fall prevention exercise with VR were positively influenced by their experience. From the perspective of the user, VR is an attractive training mode, and thus improving service provision for older people is important. © 2017 S. Karger AG, Basel.

Falls and patient safety for older adults.

Science.gov (United States)

Aronovitch, Sharon A

2006-10-01

The risk of falling increases with age. Falls in the elderly have been found to raise mortality and morbidity rates and are a leading cause of premature admission to long-term care facilities. Attention to known intrinsic and extrinsic factors that predispose to falling is important in community dwelling and institutionalized older adults. New government guidelines for long-term care facilities have helped focus attention on the safety aspect of fall risk and information about the physical and psychological impact of falling is increasing. Implementation of fall prevention protocols, including the use of fall risk assessment tools, may help reduce the incidence of falls and resultant complications.

Properties of magnetic nickel/porous-silicon composite powders

Directory of Open Access Journals (Sweden)

Toshihiro Nakamura

2012-09-01

Full Text Available The magnetic and photoluminescence (PL properties of nickel/porous-silicon (Ni/PSi composite powders are investigated. Ni/PSi composite powders are prepared by stain etching of Si powder in a HF/HNO3 solution followed by electroless plating of Ni nanoparticles on the stain-etched PSi powder in a NiCl2 solution. The Ni/PSi powders exhibit hydrophillicity, superparamagnetism caused by the deposited Ni nanoparticles, and orange-red PL owing to the nanostructured PSi surface. The degree of magnetization decreases with increasing Ni plating time, indicating its dependence on the size of the Ni nanoparticles. The Ni/PSi composite powders also show a stronger magnetization as compared to that of the Ni-particle-plated Si powder. The stronger magnetization results from the larger surface area of PSi. The PL intensity, peak wavelength, and lifetime of Ni/PSi are strongly dependent on the NiCl2 concentration. This dependence is due to the different thickness of the oxide overlayer on the PSi surface formed during the Ni plating process. The existence of the oxide overlayer also results in a small change in the PL intensity against excitation time.

Dispersion-strengthened Aluminium Products Manufactured by Powder Blending

DEFF Research Database (Denmark)

Hansen, Niels

1969-01-01

Detailed experiments carried out to examine relationship between microstructure and mechanical properties of powder-blended aluminum products are reported; their results as well as structural studies by transmission electron microscopy and tensile-and creep- testing, are given; as dispersed phase......, various oxide powders were selected on criterion that during manufacturing no reaction must taken place between metal and oxide phase; strength of powder-blended aluminum products increases and elongation decreases with decreasing particle size of aluminum powder and with increasing concentration of oxide...

Novel Fe-based nanocrystalline powder cores with excellent magnetic properties produced using gas-atomized powder

Science.gov (United States)

Chang, Liang; Xie, Lei; Liu, Min; Li, Qiang; Dong, Yaqiang; Chang, Chuntao; Wang, Xin-Min; Inoue, Akihisa

2018-04-01

FeSiBPNbCu nanocrystalline powder cores (NPCs) with excellent magnetic properties were fabricated by cold-compaction of the gas-atomized amorphous powder. Upon annealing at the optimum temperature, the NPCs showed excellent magnetic properties, including high initial permeability of 88, high frequency stability up to 1 MHz with a constant value of 85, low core loss of 265 mW/cm3 at 100 kHz for Bm = 0.05 T, and superior DC-bias permeability of 60% at a bias field of 100 Oe. The excellent magnetic properties of the present NPCs could be attributed to the ultrafine α-Fe(Si) phase precipitated in the amorphous matrix and the use of gas-atomized powder coated with a uniform insulation layer.

[Muscle and bone health as a risk factor of fall among the elderly. Kaigoyobou and prevention of falling].

Science.gov (United States)

Obuchi, Shuichi

2008-06-01

Kaigoyobou, prevention of long-term care use, is a comprehensive approach, including physical, nutritional, and social, to maintain independent living in the elderly. Prevention of falling is one useful method of Kaigoyobou. From literature review, post-fall syndrome should be primarily eliminated in the elderly since falling rate of the elderly with the falling history reported significantly greater falling rate than the other community dwelling elderly. The ability to avoid falling when they trip or slip during walking may be the most important physical function needed to be intervened. In order to train elderly person successfully, nutritional intervention need to be considered into fall prevention program.

Older persons afraid of falling reduce physical activity to prevent outdoor falls

NARCIS (Netherlands)

Wijlhuizen, G.J.; Jong, R. de; Hopman-Rock, M.

2007-01-01

Objective.: The aim of this study was to test the assumption that the level of outdoor physical activity mediates the relationship between fear of falling and actual outdoor falls according to the Task Difficulty Homeostasis Theory. Method.: A prospective follow-up study of 10 months conducted in

Problems and fall risk determinants of quality of life in older adults with increased risk of falling.

Science.gov (United States)

Lin, Sang-I; Chang, Ku-Chou; Lee, Hsuei-Chen; Yang, Yi-Ching; Tsauo, Jau-Yih

2015-05-01

Determine quality of life and its association with fall risk factors in older adults with increased risk of falling. A total of 597 community-dwelling Taiwanese older adults who were screened to have increased risk of falling participated in the present study. The fall risk factors included sociodemographics, physical and psychological function, Timed Up and Go, past fall/medical histories, fear of falling and medications. The Euro QOL EQ-5D was used to measure health-related quality of life. Pain/discomfort was the EQ-5D dimension most frequently reported to be impaired (35%), regardless of the level of fall risk or age groups, followed by mobility (25%). Hierarchical regression analysis showed that Geriatric Depression Scale, Mini-Mental State Examination, physiological function, up-and-go, fear of falling and psychotropic medication were independent predictors for total EQ-5D, explaining 68.37% of the variance. Logistic regression analysis showed that for the five EQ-5D dimensions, Geriatric Depression Scale and Up and Go time were the most common determinants. Pain/discomfort was the leading impairment, and greater Geriatric Depression Scale and longer up-and-go time were the main contributing factors in declines in quality of life in older adults with increased risk of falling. These factors are often modifiable, and their management might be considered a priority in falls prevention. © 2014 Japan Geriatrics Society.

Dry and coating of powders

International Nuclear Information System (INIS)

Alonso, M.; Alguacil, F. J.

1999-01-01

This paper presents a review on the mixing and coating of powders by dry processes. The reviews surveys fundamental works on mixture characterization (mixing index definitions and sampling techniques), mixing mechanisms and models, segregation with especial emphasis on free-surface segregation, mixing of cohesive powders and interparticle forces, ordered mixing (dry coating) including mechanism, model and applications and mixing equipment selection. (Author) 180 refs

Factors affecting the electrostatic charge of ceramic powders

International Nuclear Information System (INIS)

Lorite, I.; Romero, J.; Fernandez, J. F.

2011-01-01

The phenomenon of electrostatic charge in ceramic powders takes place when the particle surfaces enter in contact between them or with the containers. The accumulation of electrostatic charge is of relevance in ceramic powders in view of their insulating character and the risk of explosions during the material handling. In this work the main factors that affect the appearance of intrinsic charge and tribo-charge in ceramic powder have been studied. In ceramic powders of alumina it has been verified that the smallest particle sizes present an increase of the electrostatic charge of negative polarity. A correlation has been observed between the nature of the OH -surface groups and the electrostatic charge. The intrinsic charge and the tribocharge in ceramic powders can be diminished by compensating the surface groups that support the charge. The dry dispersion of nanoparticles on microparticles allows surface charge compensation with a noticeable modification of the powder agglomeration. (Author) 19 refs.

Biodegradation of thermoplastic starch/eggshell powder composites.

Science.gov (United States)

Bootklad, Munlika; Kaewtatip, Kaewta

2013-09-12

Thermoplastic starch (TPS) was prepared using compression molding and chicken eggshell was used as a filler. The effect of the eggshell powder (EP) on the properties of TPS was compared with the effect of commercial calcium carbonate (CC). The organic compound on the surface of the eggshell powder acted as a coupling agent that resulted in a strong adhesion between the eggshell powder and the TPS matrix, as confirmed by SEM micrographs. The biodegradation was determined by the soil burial test. The TPS/EP composites were more rapidly degraded than the TPS/CC composites. In addition, the eggshell powder improved the water resistance and thermal stability of the TPS. Copyright © 2013 Elsevier Ltd. All rights reserved.

Role of forgings in powder metallurgy industry

International Nuclear Information System (INIS)

Hayes, A.F.; DeRidder, A.J.

1975-01-01

Forging of powder metallurgy materials is discussed. Information and data are included on forging powder metallurgy W, Mo, In 100, Rene 95, Astroloy, Be, and Ti. It is noted that the combination of powder metallurgy and forging work provides the best product from standpoints of reproducibility, freedom from segregation, low scrap rate, and uniform mechanical properties. Experience is being used to develop contour forging from hot isostatic pressed billets or preforms. The quality of this product is under evaluation. Results show steady improvement and it is anticipated that continued effort will soon produce a reliable, less costly product. Forging can continue to be relied upon to correct subtle defects present in powder metallurgy material

Surface chemistry and microscopy of food powders

Science.gov (United States)

Burgain, Jennifer; Petit, Jeremy; Scher, Joël; Rasch, Ron; Bhandari, Bhesh; Gaiani, Claire

2017-12-01

Despite high industrial and scientific interest, a comprehensive review of the surface science of food powders is still lacking. There is a real gap between scientific concerns of the field and accessible reviews on the subject. The global description of the surface of food powders by multi-scale microscopy approaches seems to be essential in order to investigate their complexity and take advantage of their high innovation potential. Links between these techniques and the interest to develop a multi-analytical approach to investigate scientific questions dealing with powder functionality are discussed in the second part of the review. Finally, some techniques used in others fields and showing promising possibilities in the food powder domain will be highlighted.

An interdisciplinary intervention to prevent falls in community-dwelling elderly persons: protocol of a cluster-randomized trial [PreFalls

Directory of Open Access Journals (Sweden)

Schuster Tibor

2011-02-01

Full Text Available Abstract Background Prevention of falls in the elderly is a public health target in many countries around the world. While a large number of trials have investigated the effectiveness of fall prevention programs, few focussed on interventions embedded in the general practice setting and its related network. In the Prevent Falls (PreFalls trial we aim to investigate the effectiveness of a pre-tested multi-modal intervention compared to usual care in this setting. Methods/Design PreFalls is a controlled multicenter prospective study with cluster-randomized allocation of about 40 general practices to an experimental or a control group. We aim to include 382 community dwelling persons aged 65 and older with an increased risk of falling. All participating general practitioners are trained to systematically assess the risk of falls using a set of validated tests. Patients from intervention practices are invited to participate in a 16-weeks exercise program with focus on fall prevention delivered by specifically trained local physiotherapists. Patients from practices allocated to the control group receive usual care. Main outcome measure is the number of falls per individual in the first 12 months (analysis by negative binomial regression. Secondary outcomes include falls in the second year, the proportion of participants falling in the first and the second year, falls associated with injury, risk of falls, fear of falling, physical activity and quality of life. Discussion Reducing falls in the elderly remains a major challenge. We believe that with its strong focus on a both systematic and realistic fall prevention strategy adapted to primary care setting PreFalls will be a valuable addition to the scientific literature in the field. Trial registration NCT01032252

A breath actuated dry powder inhaler

NARCIS (Netherlands)

de Boer, Anne; Frijlink, Henderik W.; Hagedoorn, Paul

2015-01-01

A breath actuated dry powder inhaler with a single air circulation chamber for de-agglomeration of entrained powdered medicament using the energy of the inspiratory air stream. The chamber has a substantially polygonal sidewall, a plurality of air supply channels entering the chamber substantially

Free Falling in Stratified Fluids

Science.gov (United States)

Lam, Try; Vincent, Lionel; Kanso, Eva

2017-11-01

Leaves falling in air and discs falling in water are examples of unsteady descents due to complex interaction between gravitational and aerodynamic forces. Understanding these descent modes is relevant to many branches of engineering and science such as estimating the behavior of re-entry space vehicles to studying biomechanics of seed dispersion. For regularly shaped objects falling in homogenous fluids, the motion is relatively well understood. However, less is known about how density stratification of the fluid medium affects the falling behavior. Here, we experimentally investigate the descent of discs in both pure water and in stable linearly stratified fluids for Froude numbers Fr 1 and Reynolds numbers Re between 1000 -2000. We found that stable stratification (1) enhances the radial dispersion of the disc at landing, (2) increases the descent time, (3) decreases the inclination (or nutation) angle, and (4) decreases the fluttering amplitude while falling. We conclude by commenting on how the corresponding information can be used as a predictive model for objects free falling in stratified fluids.

The neurobiology of falls.

Science.gov (United States)

Fasano, Alfonso; Plotnik, Meir; Bove, Francesco; Berardelli, Alfredo

2012-12-01

Falling is a major clinical problem; especially, in elderly population as it often leads to fractures, immobilization, poor quality of life and life-span reduction. Given the growing body of evidences on the physiopathology of balance disorders in humans, in recent years the approach of research on falls has completely changed and new instruments and new definitions have been formulated. Among them, the definition of "idiopathic faller" (i.e. no overt cause for falling in a given subject) represented a milestone in building the "science of falling". This review deals with the new determinants of the neurobiology of falling: (1) the role of motor impairment and particularly of those "mild parkinsonian signs" frequently detectable in elderly subjects, (2) the role of executive and attentive resources when coping with obstacles, (3) the role of vascular lesions in "highest level gait disorder" (a condition tightly connected with senile gait, cautious gait and frailty), (4) the role of the failure of automaticity or inter-limbs coordination/symmetry during walking and such approach would definitely help the development of screening instrument for subjects at risk (still lacking in present days). This translational approach will lead to the development of specific therapeutic interventions.

Fall Prevention: Simple Tips to Prevent Falls

Science.gov (United States)

... a gentle exercise that involves slow and graceful dance-like movements. Such activities reduce the risk of ... healthy-lifestyle/healthy-aging/in-depth/fall-prevention/art-20047358 . Mayo Clinic Footer Legal Conditions and Terms ...

Surface quality analysis of die steels in powder-mixed electrical discharge machining using titan powder in fine machining

Directory of Open Access Journals (Sweden)

Banh Tien Long

2016-06-01

Full Text Available Improving the quality of surface molds after electrical discharge machining is still being considered by many researchers. Powder-mixed dielectric in electrical discharge machining showed that it is one of the processing methods with high efficiency. This article reports on the results of surface quality of mold steels after powder-mixed electrical discharge machining using titanium powder in fine machining. The process parameters such as electrode material, workpiece material, electrode polarity, pulse on-time, pulse off-time, current, and titanium powder concentration were considered in the research. These materials are most commonly used with die-sinking electrical discharge machining in the manufacture of molds and has been selected as the subject of research: workpiece materials were SKD61, SKT4, and SKD11 mold steels, and electrode materials were copper and graphite. Taguchi’s method is used to design experiments. The influence of the parameters on surface roughness was evaluated through the average value and ratio (S/N. Results showed that the parameters such as electrical current, electrode material, pulse on-time, electrode polarity, and interaction between the electrode materials with concentration powder mostly influence surface roughness and surface roughness at optimal parameters SRopt = 1.73 ± 0.39 µm. Analysis of the surface layer after powder-mixed electrical discharge machining using titanium powder in optimal conditions has shown that the white layer with more uniform thickness and increased hardness (≈861.0 HV, and amount and size of microscopic cracks, is reduced. This significantly leads to the increase in the quality of the surface layer.

Optimization of Premix Powders for Tableting Use.

Science.gov (United States)

Todo, Hiroaki; Sato, Kazuki; Takayama, Kozo; Sugibayashi, Kenji

2018-05-08

Direct compression is a popular choice as it provides the simplest way to prepare the tablet. It can be easily adopted when the active pharmaceutical ingredient (API) is unstable in water or to thermal drying. An optimal formulation of preliminary mixed powders (premix powders) is beneficial if prepared in advance for tableting use. The aim of this study was to find the optimal formulation of the premix powders composed of lactose (LAC), cornstarch (CS), and microcrystalline cellulose (MCC) by using statistical techniques. Based on the "Quality by Design" concept, a (3,3)-simplex lattice design consisting of three components, LAC, CS, and MCC was employed to prepare the model premix powders. Response surface method incorporating a thin-plate spline interpolation (RSM-S) was applied for estimation of the optimum premix powders for tableting use. The effect of tablet shape identified by the surface curvature on the optimization was investigated. The optimum premix powder was effective when the premix was applied to a small quantity of API, although the function of premix was limited in the case of the formulation of large amount of API. Statistical techniques are valuable to exploit new functions of well-known materials such as LAC, CS, and MCC.

Dance movement therapy and falls prevention.

Science.gov (United States)

Veronese, Nicola; Maggi, Stefania; Schofield, Patricia; Stubbs, Brendon

2017-08-01

Falls are a leading cause of morbidity, healthcare use and mortality. Dance is a popular form of physical activity among older people and previous research has suggested that it may improve various health outcomes in this population, including balance, gait and muscle performance. A systematic review of the potential benefits of dance on falls and fear of falling is lacking. Thus, we conducted a systematic review considering all randomized controls trials (RCTs) investigating if dance can reduce falls and improve fear of falling in older adults. Major databases were searched from inception until 1 March 2017 and a total of 10 RCTs were identified, which included a total of 680 people (n=356 dance, n=324 control). Overall, the mean age of the samples was 69.4 years, and 75.2% were female. Across four RCTs, dance therapy reduced falls versus usual care in only one study. Dance therapy improved fear of falling in two out of three included RCTs. There were no serious adverse events reported in the RCTs. In summary, we found a paucity of studies investigating the effect of dance on falls and fear of falling and the evidence base is preliminary and equivocal. Given the heterogeneity of the included samples and interventions, in addition to the short-term follow-up, no firm conclusions can be drawn. However, dance appears to be safe and, given its popularity and demonstrated benefits on other health/wellbeing outcomes in older adults, it is important that future research considers its potential benefits on falls/fear of falling in older age. Copyright © 2017 Elsevier B.V. All rights reserved.

The study of neutron transport by oscillation method; Etude du transport des neutrons par la methode de modulation

Energy Technology Data Exchange (ETDEWEB)

Raievski, V

1959-07-01

The oscillation method is of very general use for studying the behavior of thermal neutrons in media. The main experiments are described and a general theory of them is given. This theory, which is presented in the first part, is established using the two-group approximation which has proved its efficiency in the case of thermal neutron piles. The validity of the two-group approximation is recalled. This allows definition of the meaning of the parameters used in the theory and which are measured in these experiments. The experiments carried out by this method are described, especially those performed at the Centre d'Etudes Nucleaires de Saclay where the method has been extensively used. These experiments are interpreted by means of the general theory given previously. In this way, the identity of parameters measured by this method and those given by the theory is proved. This is particularly conclusive is the case of the mean life of neutrons in a pile. (author) [French] La methode de modulation est un procede tres general d'etude des proprietes neutroniques des milieux contenant des neutrons thermiques. Le present rapport a pour but de decrire les principales de ces experiences et d'en donner une theorie generale. Cette theorie, exposee dans la premiere partie, est etablie dons le cadre de l'approximation a deux groupes de vitesse qui a prouve son efficacite dons le cas des piles a neutrons thermiques. Le domaine de validite de l'approximation a deux groupes est rappele au debut, ce qui permet de definir avec precision la signification des parametres qui entrent dons la theorie et qui font l'objet de ces mesures. La deuxieme partie decrit les experiences realisees, en particulier celles effectuees au Centre d'Etudes Nucleaires de Saclay ou la methode a ete considerablement developpee. Ces experiences sont interpretees dans le cadre de la theorie generale exposee precedemment. On prouve ainsi l'identite des parametres mesures par cette methode et de ceux figurant

Fall speed measurement and high-resolution multi-angle photography of hydrometeors in free fall

OpenAIRE

T. J. Garrett; C. Fallgatter; K. Shkurko; D. Howlett

2012-01-01

We describe here a new instrument for imaging hydrometeors in free fall. The Multi-Angle Snowflake Camera (MASC) captures high-resolution photographs of hydrometeors from three angles while simultaneously measuring their fall speed. Based on the stereoscopic photographs captured over the two months of continuous measurements obtained at a high altitude location within the Wasatch Front in Utah, we derive statistics for fall speed, hydrometeor size, shape, orientation and asp...

Production and properties of boride powders

International Nuclear Information System (INIS)

Klinskaya, N.A.; Koroleva, E.B.; Petrunichev, V.A.

1990-01-01

Results of plasma metallization of boride powders 40-80 μ diam. are presented. Peculiarities of changes of granulometric powder composition and of metallic cover on refractory cores were investigated. There are shown size- and compositional cores effects on metallization level of poders and on cover structure

Quality of clay-powders of industrial assortment

Energy Technology Data Exchange (ETDEWEB)

Lityayeva, Z A; Dzetl, B G; Goncharenko, N N; Naurova, I V; Rybchenko, V I; Voyevodin, L I

1979-01-01

Nomenclature was developed for the quality indicators of clay powders which took into consideration the foreign experience, and it is suggested that a suspension of clay powders be viewed as the simplest type of drilling. In this case the technique of preparing the suspensions approaches the maximum to that used in the recommended standard (TU-39-043-074). The output of solution is determined with standardized effective viscosity /eta/ ef =/sup 20/ /SUP cP/ on a series domestic rotary viscosimeter VSN-3 with gradient of shear velocity EPSILON=666 sec/sup -1/; with EPSILON=1022 sec /sup -1//eta/ /SUB ef/ = 15 cP. This makes it possible to obtain data comparable to the foreign standards regarding the output of the fluid from the powders. According to the suggested technique, the clay powder is dispersed for 20-30 minutes in water or saturated solution of NaC1 in a mixing unit ''Voronezh2'' with rotation frequency of 9000 rpm, is left to rest and is again dispersed for 15 minutes. Then the dynamic shear stress (P /SUB k2/ ), plastic viscosity (/eta/ /SUB ef/ ), coefficients of coagulation (K /SUB c/ ) and thyxotropic (K /SUB T/ ) structure-formation are defined. Measurements are made on the instrument FLR-1 of water output with 0.7 (B) or 0.1 (B) MPa. According to this technique, a comparison was made of the domestic powders of industrial assortment with the powder ''Aquagel'' widely used abroad. It was established that only the modified concrete powders with correct selection of reagents can compete with the foreign.

3D Model Studies on the Effect of Bed and Powder Type Upon Radial Static Pressure and Powder Distribution in Metallurgical Shaft Furnaces

Directory of Open Access Journals (Sweden)

Panic B.

2017-09-01

Full Text Available The flow of gases in metallurgical shaft furnaces has a decisive influence on the course and process efficiency. Radial changes in porosity of the bed cause uneven flow of gas along the radius of the reactor, which sometimes is deliberate and intentional. However, holdup of solid particles in descending packed beds of metallurgical shaft furnaces can lead to unintentional changes in porosity of the bed along the radial reactor. Unintentional changes in porosity often disrupt the flow of gas causing poor performance of the furnace. Such disruptions of flow may occur in the blast furnace due to high level of powder content in gas caused by large amount of coal dust/powder insufflated as fuel substitute. The paper describes the model test results of radial distribution of static pressure and powder hold up within metallurgical reactor. The measurements were carried out with the use of 3D physical model of two-phase flow gas-powder in the moving (descending packed bed. Sinter or blast furnace pellets were used as packed bed while carbon powder or iron powder were used as the powder. Wide diversity within both static pressure distribution and powder distribution along the radius of the reactor were observed once the change in the type of powder occurred.

Advances in food powder agglomeration engineering.

Science.gov (United States)

Cuq, B; Gaiani, C; Turchiuli, C; Galet, L; Scher, J; Jeantet, R; Mandato, S; Petit, J; Murrieta-Pazos, I; Barkouti, A; Schuck, P; Rondet, E; Delalonde, M; Dumoulin, E; Delaplace, G; Ruiz, T

2013-01-01

Food powders are used in everyday life in many ways and offer technological solutions to the problem of food production. The natural origin of food powders, diversity in their chemical composition, variability of the raw materials, heterogeneity of the native structures, and physicochemical reactivity under hydrothermal stresses contribute to the complexity in their behavior. Food powder agglomeration has recently been considered according to a multiscale approach, which is followed in the chapter layout: (i) at the particle scale, by a presentation of particle properties and surface reactivity in connection with the agglomeration mechanisms, (ii) at the mechanisms scale, by describing the structuration dynamics of agglomerates, (iii) at the process scale, by a presentation of agglomeration technologies and sensors and by studying the stress transmission mode in the powder bed, and finally (iv) by an integration of the acquired knowledge, thanks to a dimensional analysis carried out at each scale. Copyright © 2013 Elsevier Inc. All rights reserved.

Properties and sinterability of wet and dry attrition-milled OREOXed powder

International Nuclear Information System (INIS)

Lee, J. W.; Kim, J. H.; Kim, W. K.; Park, K. I.; Lee, J. W.

2001-01-01

The powder properties and sinterability were investigated with the powder prepared by wet and dry attrition milling of OREOX-treated powder. The OREOX-treated powder was prepared from the simulated spent fuel. Powder having less than 1 μm of average particle size could be obtained by dry milling, but not be obtained by wet milling. Thus, specific surface area of dry milled powder was higher than that of wet milled powder. With increasing of milling time, dry milled powder formed dense agglomerate while wet milled powder showed loose agglomerate. The pellets with higher than 95% T.D. of sintered density and larger than 7 μm of grain size were made with the milled powder regardless of milling method. The milling time in wet milling has greatly improved the sinterability. The pellets produced with dry milled powder have higher sintered density and larger grain size

Functional Performances on Admission Predict In-Hospital Falls, Injurious Falls, and Fractures in Older Patients: A Prospective Study.

Science.gov (United States)

Hars, Mélany; Audet, Marie-Claude; Herrmann, François; De Chassey, Jean; Rizzoli, René; Reny, Jean-Luc; Gold, Gabriel; Ferrari, Serge; Trombetti, Andrea

2018-05-01

Falls are common among older inpatients and remain a great challenge for hospitals. Despite the relevance of physical impairments to falls, the prognostic value of performance-based functional measures for in-hospital falls and injurious falls remains unknown. This study aimed to determine the predictive ability and accuracy of various functional tests administered at or close to admission in a geriatric hospital to identify in-hospital fallers and injurious fallers. In this prospective study, conducted in a geriatric hospital in Geneva, Switzerland, 807 inpatients (mean age 85.0 years) were subjected to a battery of functional tests administered by physiotherapists within 3 days (interquartile range 1 to 6) of admission, including Short Physical Performance Battery (SPPB), simplified Tinetti, and Timed Up and Go tests. Patients were prospectively followed up for falls and injurious falls until discharge using mandatory standardized incident report forms and electronic patients' records. During a median length of hospital stay of 23 days (interquartile range 14 to 36), 329 falls occurred in 189 (23.4%) patients, including 161 injurious falls of which 24 were serious. In-hospital fallers displayed significantly poorer functional performances at admission on all tests compared with non-fallers (p performances on all functional tests predicted in-hospital falls and injurious falls (p poor functional performances, as assessed by SPPB, are independent predictors of in-hospital falls, injurious falls, and fractures in patients admitted to a geriatric hospital. These findings should help to design preventive strategies for in-hospital falls and support the adoption of objective performance-based functional measures into routine hospital practice. © 2018 American Society for Bone and Mineral Research. © 2018 American Society for Bone and Mineral Research.

Evaluation of the Frails' Fall Efficacy by Comparing Treatments (EFFECT) on reducing fall and fear of fall in moderately frail older adults: study protocol for a randomised control trial.

Science.gov (United States)

Kwok, Boon Chong; Mamun, Kaysar; Chandran, Manju; Wong, Chek Hooi

2011-06-18

Falls are common in frail older adults and often result in injuries and hospitalisation. The Nintendo® Wii™ is an easily available exercise modality in the community which has been shown to improve lower limb strength and balance. However, not much is known on the effectiveness of the Nintendo® Wii™ to improve fall efficacy and reduce falls in a moderately frail older adult. Fall efficacy is the measure of fear of falling in performing various daily activities. Fear contributes to avoidance of activities and functional decline. This randomised active-control trial is a comparison between the Nintendo WiiActive programme against standard gym-based rehabilitation of the older population. Eighty subjects aged above 60, fallers and non-fallers, will be recruited from the hospital outpatient clinic. The primary outcome measure is the Modified Falls Efficacy Scale and the secondary outcome measures are self-reported falls, quadriceps strength, walking agility, dynamic balance and quality of life assessments. The study is the first randomised control trial using the Nintendo Wii as a rehabilitation modality investigating a change in fall efficacy and self-reported falls. Longitudinally, the study will investigate if the interventions can successfully reduce falls and analyse the cost-effectiveness of the programme.

Dielectric properties of tantalum powder with broccoli-like morphology

Energy Technology Data Exchange (ETDEWEB)

Baba, Masahiko [Department of Energy Science and Technology, Kyoto University, Yoshida-Honmachi, Sakyo-ku, Kyoto 606-8501 (Japan); Suzuki, Ryosuke O [Department of Energy Science and Technology, Kyoto University, Yoshida-Honmachi, Sakyo-ku, Kyoto 606-8501 (Japan)

2005-04-19

Metallic tantalum powder with broccoli-like morphology, consisting of spherical fine particles and of long rods or thin plates, was prepared in a hundred gram scale by calcium reduction of Ta{sub 2}O{sub 5} in molten CaCl{sub 2}. The properties as electrolytic capacitor were evaluated in comparison with commercial powder obtained by Na reduction and with powder consisting of only fine particles obtained by Ca reduction. The capacitance was larger than that of conventional powder with the same surface area, because the broccoli-like powder showed a strong resistance against shrinkage during high temperature annealing due to the framework of branches. The powder with new broccoli-like morphology can circumvent the conventional treatments for grain size control and gas removal.

Dielectric properties of tantalum powder with broccoli-like morphology

International Nuclear Information System (INIS)

Baba, Masahiko; Suzuki, Ryosuke O.

2005-01-01

Metallic tantalum powder with broccoli-like morphology, consisting of spherical fine particles and of long rods or thin plates, was prepared in a hundred gram scale by calcium reduction of Ta 2 O 5 in molten CaCl 2 . The properties as electrolytic capacitor were evaluated in comparison with commercial powder obtained by Na reduction and with powder consisting of only fine particles obtained by Ca reduction. The capacitance was larger than that of conventional powder with the same surface area, because the broccoli-like powder showed a strong resistance against shrinkage during high temperature annealing due to the framework of branches. The powder with new broccoli-like morphology can circumvent the conventional treatments for grain size control and gas removal

FEAR OF FALLING AMONG COMMUNITY DWELLING OLDER ADULTS

Directory of Open Access Journals (Sweden)

Michaela Dingová

2017-03-01

Full Text Available Aim: The aim of the study was to describe experience with falls, fear of falling, perceptions of the consequences of falls and how the fear of falling affects daily life in community-dwelling older adults. Design: The study used a qualitative design to describe the lived experiences of community-dwelling older adults with the fear of falling. Methods: Semi-structured interviews were conducted individually with six participants who reported the fear of falling. Results: Five main areas emerged from data analysis: development of the fear of falling, feared consequences of falling, activities curtailment, fall prevention behavior and meaning of social support in daily life. The fear of falling was described as a negative experience, directly linked to fall consequences such as physical injury, incapacitation, loss of autonomy, fear of dependence and experience of humiliating conditions. To maintain a certain level of independence in daily life, the participants chose to avoid falls by activity curtailment, organizing their lives more carefully and getting support from others. Conclusion: All participants identified that they had discovered their fear of falling after experiencing falls. The fear of falling was associated with feared consequences of a potential fall and had an impact on their daily life. The participant also mentioned other contributors to their fear of falling, including ill health and aging. Keywords: Fear of falling, older adults, perceived consequences of falls, daily life.

Development and directions of powder diffraction on proteins

Energy Technology Data Exchange (ETDEWEB)

Von Dreele, R B; Besnard, C; Basso, S; Camus, F; Pattison, P; Schiltz, M; Wright, J P; Margiolaki, R; Fitch, A N; Fox, G C; Prugoveeki, S; Beckers, D; Helliwell, J R; Helliwell, M; Jones, R H; Roberts, M A; Miura, K; Kahn, R; Giacovazzo, C; Altomare, A; Caliandro, R; Camalli, M; Cuocci, C; Moliterni, A G.G.; Rizzi, R; Hinrichsen, B; Kern, A; Coelho, A A; Degen, T; Kokkinidis, M; Fadouloglou, V; Gazi, A; Panopoulos, N; Pinotsis, N; Wilmanns, M; Norrman, M; Schluckebier, G; Prugoveeki, B; Dilovic, J; Matkovic-Calogovic, D; Bill, David; Markvardsen, A; Grosse-Kunstleve, R; Rius, J; Glykos Nicholas, M; Murshudov, G N

2007-07-01

X-ray diffraction is one of the most important method for obtaining information about the structure of proteins and thereby for gaining insight into fundamental biological and biochemical mechanisms. This seminar was dedicated to X-ray powder diffraction and was organized around 6 sessions: 1) what can powder diffraction do for proteins?, 2) adapting experimentally to proteins, 3) interpreting powder data, 4) the world of protein crystallography, 5) advancing methods for powder data analysis, and 6) transferable methods from single crystals. This document gathers the abstracts of the 23 papers presented. (A.C.)

Development and directions of powder diffraction on proteins

International Nuclear Information System (INIS)

Von Dreele, R.B.; Besnard, C.; Basso, S.; Camus, F.; Pattison, P.; Schiltz, M.; Wright, J.P.; Margiolaki, R.; Fitch, A.N.; Fox, G.C.; Prugoveeki, S.; Beckers, D.; Helliwell, J.R.; Helliwell, M.; Jones, R.H.; Roberts, M.A.; Miura, K.; Kahn, R.; Giacovazzo, C.; Altomare, A.; Caliandro, R.; Camalli, M.; Cuocci, C.; Moliterni, A.G.G.; Rizzi, R.; Hinrichsen, B.; Kern, A.; Coelho, A.A.; Degen, T.; Kokkinidis, M.; Fadouloglou, V.; Gazi, A.; Panopoulos, N.; Pinotsis, N.; Wilmanns, M.; Norrman, M.; Schluckebier, G.; Prugoveeki, B.; Dilovic, J.; Matkovic-Calogovic, D.; Bill, David; Markvardsen, A.; Grosse-Kunstleve, R.; Rius, J.; Glykos Nicholas, M.; Murshudov, G.N.

2007-01-01

X-ray diffraction is one of the most important method for obtaining information about the structure of proteins and thereby for gaining insight into fundamental biological and biochemical mechanisms. This seminar was dedicated to X-ray powder diffraction and was organized around 6 sessions: 1) what can powder diffraction do for proteins?, 2) adapting experimentally to proteins, 3) interpreting powder data, 4) the world of protein crystallography, 5) advancing methods for powder data analysis, and 6) transferable methods from single crystals. This document gathers the abstracts of the 23 papers presented. (A.C.)

Relationship Between Difficulties in Daily Activities and Falling: Loco-Check as a Self-Assessment of Fall Risk.

Science.gov (United States)

Akahane, Manabu; Maeyashiki, Akie; Yoshihara, Shingo; Tanaka, Yasuhito; Imamura, Tomoaki

2016-06-20

People aged 65 years or older accounted for 25.1% of the Japanese population in 2013, and this characterizes the country as a "super-aging society." With increased aging, fall-related injuries are becoming important in Japan, because such injuries underlie the necessity for nursing care services. If people could evaluate their risk of falling using a simple self-check test, they would be able to take preventive measures such as exercise, muscle training, walking with a cane, or renovation of their surroundings to remove impediments. Loco-check is a checklist measure of early locomotive syndrome (circumstances in which elderly people need nursing care service or are at high risk of requiring the service within a short time), prepared by the Japanese Orthopaedic Association (JOA) in 2007, but it is unclear if there is any association between this measure and falls. To investigate the association between falls during the previous year and the 7 "loco-check" daily activity items and the total number of items endorsed, and sleep duration. We conducted an Internet panel survey. Subjects were 624 persons aged between 30 and 90 years. The general health condition of the participants, including their experience of falling, daily activities, and sleep duration, was investigated. A multivariate analysis was carried out using logistic regression to investigate the relationship between falls in the previous year and difficulties with specific daily activities and total number of difficulties (loco-check) endorsed, and sleep duration, adjusting for sex and age. One-fourth of participants (157 persons) experienced at least one fall during the previous year. Fall rate of females (94/312: 30.1%) was significantly higher than that of males (63/312: 20.2%). Fall rate of persons aged more than 65 years (80/242: 33.1%) was significantly higher than that of younger persons (77/382: 20.2%). Logistic regression analysis revealed that daily activities such as "impossibility of getting

A simple strategy for fall events detection

KAUST Repository

Harrou, Fouzi

2017-01-20

The paper concerns the detection of fall events based on human silhouette shape variations. The detection of fall events is addressed from the statistical point of view as an anomaly detection problem. Specifically, the paper investigates the multivariate exponentially weighted moving average (MEWMA) control chart to detect fall events. Towards this end, a set of ratios for five partial occupancy areas of the human body for each frame are collected and used as the input data to MEWMA chart. The MEWMA fall detection scheme has been successfully applied to two publicly available fall detection databases, the UR fall detection dataset (URFD) and the fall detection dataset (FDD). The monitoring strategy developed was able to provide early alert mechanisms in the event of fall situations.

Impact of falls and fear of falling on health-related quality of life in patients with Parkinson's disease

NARCIS (Netherlands)

Grimbergen, Y.A.M.; Schrag, A.; Mazibrada, G.; Borm, G.F.; Bloem, B.R.

2013-01-01

Postural instability, recurrent falls and fear of falling are common in advanced Parkinson's disease (PD). We examined the impact of fall frequency, fear of falling, balance confidence and objectively measured balance impairment (using Tinetti's Mobility Index) on health-related quality of life

[Influence of high fall-related self-efficacy on falls due to dissociation with ADL among elderly women in nursing homes].

Science.gov (United States)

Kato, Chikako; Ida, Kunio; Harada, Atsushi

2009-09-01

We examined the influence of high fall-related self-efficacy on falls due to dissociation with activities of daily living (ADL) among elderly women in nursing homes. We enrolled 72 female nursing home residents who were 70 years old or over and who scored 18 or higher on the Mini-Mental State Examination (MMSE). Subjects were classified into three groups based on the relationship between ADL and fall-related self-efficacy derived from a scattergram of the Functional Independence Measure (FIM) motor items and Falls Efficacy Scale (FES). The three groups were: group I which had low ADL and high fall-related self-efficacy (n=25); group II which had high ADL and low fall-related self-efficacy (n=30); and group III which had a correlation of ADL and fall-related self-efficacy in the 95% confidence interval (n=17). Then, we investigated the incidence of falls and the number of falls after 6 months in the three groups. The risk factor of falls was also investigated using multiple logistic regression analysis. The incidence and number of falls were significantly different in the three groups after 6 months. Moreover, the incidence of those falling was significantly different between group I and group III. The occurrence of falls was also significantly related with a past history of falls, FES, and group I which had low ADL and high fall-related self-efficacy. These findings suggest that the risk of falling increases in the presence of excessive fall-related self-efficacy dissociated from ADL.

Risk factors, incidence, consequences and prevention strategies for falls and fall-injury within older indigenous populations: a systematic review.

Science.gov (United States)

Lukaszyk, Caroline; Harvey, Lara; Sherrington, Cathie; Keay, Lisa; Tiedemann, Anne; Coombes, Julieann; Clemson, Lindy; Ivers, Rebecca

2016-12-01

To examine the risk factors, incidence, consequences and existing prevention strategies for falls and fall-related injury in older indigenous people. Relevant literature was identified through searching 14 electronic databases, a range of institutional websites, online search engines and government databases, using search terms pertaining to indigenous status, injury and ageing. Thirteen studies from Australia, the United States, Central America and Canada were identified. Few studies reported on fall rates but two reported that around 30% of indigenous people aged 45 years and above experienced at least one fall during the past year. The most common hospitalised fall injuries among older indigenous people were hip fracture and head injury. Risk factors significantly associated with falls within indigenous populations included poor mobility, a history of stroke, epilepsy, head injury, poor hearing and urinary incontinence. No formally evaluated, indigenous-specific fall prevention interventions were identified. Falls are a significant and growing health issue for older indigenous people worldwide that can lead to severe health consequences and even death. No fully-evaluated, indigenous-specific fall prevention programs were identified. Implications for Public Health: Research into fall patterns and fall-related injury among indigenous people is necessary for the development of appropriate fall prevention interventions. © 2016 Public Health Association of Australia.

Powder injection molding of Stellite 6 powder: Sintering, microstructural and mechanical properties

International Nuclear Information System (INIS)

Gülsoy, H. Özkan; Özgün, Özgür; Bilketay, Sezer

2016-01-01

The purpose of this study was to produce Co-based Stellite 6 superalloy components by using the method of Powder Injection Molding (PIM) and to characterize the microstructural and mechanical properties of the produced components. The experimental studies were started through the formation of feedstock by mixing Stellite 6 powder with a multicomponent binder system. Prepared feedstock was formed by utilizing powder injection molding technique. Then the molded samples were subjected to the solvent and thermal debinding processes. Different sintering cycles were applied to the raw components for the purpose of determining the optimum sintering conditions. The densities of the sintered components were determined in accordance with the Archimedes' principle. The microstructural characterization was performed through scanning electron microscope (SEM) analysis, energy dispersive spectrometry (EDS) analyses, and X-ray diffraction (XRD) analysis. Hardness measurement and tensile test were conducted in order to determine the mechanical properties. The results illustrated that the injection molded Stellite 6 components were composed of fine and equiaxed grains, plenty of carbide precipitates exhibiting homogenous distribution throughout the microstructure formed at the grain boundaries and thus the mechanical properties were considerably high.

An update on falls

NARCIS (Netherlands)

Bloem, B.R.; Steijns, J.A.G.; Smits-Engelsman, B.C.M.

2003-01-01

Purpose of review: Falls among elderly persons create immense social problems because of their association with physical decline, serious psychosocial consequences, negative impact on the quality of life, and markedly reduced survival. In addition, falls pose high costs to the public health service.

An update on falls.

NARCIS (Netherlands)

Bloem, B.R.; Steijns, J.A.G.; Smits-Engelsman, B.C.M.

2003-01-01

PURPOSE OF REVIEW: Falls among elderly persons create immense social problems because of their association with physical decline, serious psychosocial consequences, negative impact on the quality of life, and markedly reduced survival. In addition, falls pose high costs to the public health service.

Some characteristics of urea-formaldehyde powder adhesives

Directory of Open Access Journals (Sweden)

Miljković Jovan

2006-01-01

Full Text Available Urea-formaldehyde (UF glue resins were the most important type of adhesives in the wood industry last 60 years, especially for the production of wood based panels. More convenient spray dried UF powders went into use last two decades. Small and medium private wood processing plants in Serbia prefer to use such powder adhesives, since they are more convenient for small capacity production. There is no production of UF powder resin in Serbia so necessary quantities are imported from abroad including producers from Asia. However, their characteristics are variable, dependent on syntheses steps and not well known among users. Objective of this research was to determine conveniences and lacks in application of two imported UF powder resins in comparison to domestic UF emulsion.

Nanostructured hydroxyapatite powders produced by a flame-based technique

Energy Technology Data Exchange (ETDEWEB)

Trommer, R.M., E-mail: rafael_trommer@yahoo.com.br [Ceramic Materials Laboratory, av. Osvaldo Aranha 99/705, 90035190, Porto Alegre, RS (Brazil); Santos, L.A. [Biomaterials Laboratory, av. Bento Goncalves 9500, Campus do Vale Setor IV Predio 74 Sala 123, 91501970, Porto Alegre, RS (Brazil); Bergmann, C.P. [Ceramic Materials Laboratory, av. Osvaldo Aranha 99/705, 90035190, Porto Alegre, RS (Brazil)

2009-08-01

In this work we reported the production of hydroxyapatite (HA) powder, one of the most studied calcium phosphates in the bioceramics field, using a cost-effective apparatus, composed by three major components: the atomization device, the pilot and main flames and finally the powder collector system. Calcium acetate and ammonium phosphate, diluted in ethanol and water, were used as salts in the precursor solution. The Ca/P molar ratio in the precursor solution was 1.65, equivalent to biological hydroxyapatite. After its production and collection, HA powder was calcined at 600 deg. C for 2 h. X-ray diffraction analysis pointed to the formation of crystalline hydroxyapatite powders. Carbonate was identified in the powders by Fourier-transform infrared (FTIR) spectroscopy. Scanning electronic microscopy (SEM) showed that the powders were composed of spherical primary particles and secondary aggregates, with the morphology unchanged after calcination. By transmission electronic microscopy (TEM), it was observed that the crystallite size of the primary particles was 24.8 {+-} 5.8 nm, for the calcined powder. The specific surface area was 15.03 {+-} 6.4 and 26.50 {+-} 7.6 m{sup 2}/g, for the as-synthetized and calcined powder respectively.

Survival of falling robots

Science.gov (United States)

Cameron, Jonathan M.; Arkin, Ronald C.

1992-01-01

As mobile robots are used in more uncertain and dangerous environments, it will become important to design them so that they can survive falls. In this paper, we examine a number of mechanisms and strategies that animals use to withstand these potentially catastrophic events and extend them to the design of robots. A brief survey of several aspects of how common cats survive falls provides an understanding of the issues involved in preventing traumatic injury during a falling event. After outlining situations in which robots might fall, a number of factors affecting their survival are described. From this background, several robot design guidelines are derived. These include recommendations for the physical structure of the robot as well as requirements for the robot control architecture. A control architecture is proposed based on reactive control techniques and action-oriented perception that is geared to support this form of survival behavior.

Survival of falling robots

Science.gov (United States)

Cameron, Jonathan M.; Arkin, Ronald C.

1992-02-01

As mobile robots are used in more uncertain and dangerous environments, it will become important to design them so that they can survive falls. In this paper, we examine a number of mechanisms and strategies that animals use to withstand these potentially catastrophic events and extend them to the design of robots. A brief survey of several aspects of how common cats survive falls provides an understanding of the issues involved in preventing traumatic injury during a falling event. After outlining situations in which robots might fall, a number of factors affecting their survival are described. From this background, several robot design guidelines are derived. These include recommendations for the physical structure of the robot as well as requirements for the robot control architecture. A control architecture is proposed based on reactive control techniques and action-oriented perception that is geared to support this form of survival behavior.

[Study of relationship between powder-size gradation and mechanical properties of Zirconia toughened glass infiltrated nanometer-ceramic composite powder].

Science.gov (United States)

Chai, Feng; Xu, Ling; Liao, Yun-mao; Chao, Yong-lie

2003-07-01

The fabrication of all-ceramic dental restorations is challenged by ceramics' relatively low flexural strength and intrinsic poor resistance to fracture. This paper aimed at investigating the relationships between powder-size gradation and mechanical properties of Zirconia toughened glass infiltrated nanometer-ceramic composite (Al(2)O(3)-nZrO(2)). Al(2)O(3)-nZrO(2) ceramics powder (W) was processed by combination methods of chemical co-precipitation and ball milling with addition of different powder-sized ZrO(2). Field-emission scanning electron microscopy was used to determine the particle size distribution and characterize the particle morphology of powders. The matrix compacts were made by slip-casting technique and sintered to 1,450 degrees C and flexural strength and the fracture toughness of them were measured. 1. The particle distribution of Al(2)O(3)-nZrO(2) ceramics powder ranges from 0.02 - 3.5 micro m and among them the superfine particles almost accounted for 20%. 2. The ceramic matrix samples with addition of nZrO(2) (W) showed much higher flexural strength (115.434 +/- 5.319) MPa and fracture toughness (2.04 +/- 0.10) MPa m(1/2) than those of pure Al(2)O(3) ceramics (62.763 +/- 7.220 MPa; 1.16 +/- 0.02 MPa m(1/2)). The particle size of additive ZrO(2) may impose influences on mechanical properties of Al(2)O(3)-nZrO(2) ceramics matrix. Good homogeneity and reasonable powder-size gradation of ceramic powder can improve the mechanical properties of material.

On suitability of novel fluidised bed technique for separation of metallic powders during commercial powder metallurgical processing

NARCIS (Netherlands)

Ritherdon, J; Dechsiri, C; Jones, AR; Hoffmann, AC; Wright, IG

Experiments have been performed to test the efficiency with which a novel fluidised bed technique could separate different metallic powders in terms of size and density. The overall aim was to assess the potential of this technique for the commercial separation of defective powder fractions from

Comparison of fall prediction by the Hessisch Oldendorf Fall Risk Scale and the Fall Risk Scale by Huhn in neurological rehabilitation: an observational study.

Science.gov (United States)

Hermann, Olena; Schmidt, Simone B; Boltzmann, Melanie; Rollnik, Jens D

2018-05-01

To calculate scale performance of the newly developed Hessisch Oldendorf Fall Risk Scale (HOSS) for classifying fallers and non-fallers in comparison with the Risk of Falling Scale by Huhn (FSH), a frequently used assessment tool. A prospective observational trail was conducted. The study was performed in a large specialized neurological rehabilitation facility. The study population ( n = 690) included neurological and neurosurgery patients during neurological rehabilitation with varying levels of disability. Around the half of the study patients were independent and dependent in the activities of daily living (ADL), respectively. Fall risk of each patient was assessed by HOSS and FSH within the first seven days after admission. Event of fall during rehabilitation was compared with HOSS and FSH scores as well as the according fall risk. Scale performance including sensitivity and specificity was calculated for both scales. A total of 107 (15.5%) patients experienced at least one fall. In general, fallers were characterized by an older age, a prolonged length of stay, and a lower Barthel Index (higher dependence in the ADL) on admission than non-fallers. The verification of fall prediction for both scales showed a sensitivity of 83% and a specificity of 64% for the HOSS scale, and a sensitivity of 98% with a specificity of 12% for the FSH scale, respectively. The HOSS shows an adequate sensitivity, a higher specificity and therefore a better scale performance than the FSH. Thus, the HOSS might be superior to existing assessments.

Study on Quality Aggregate Construction Powder

International Nuclear Information System (INIS)

Myat Ko; Kyaw Naing; Thazin Lwin; Khin Mar Tun

2008-03-01

This research work deals with a view to promote cement replacement materials i-e aggregate construction powder, also known as building powder or construction powder . It has been used as lime substituent in construction work in Myanmar since 1990's. It is mixed with other construction materials such as cement, sand, etc. and used in plastering, tiling, arranging bricks and smoothing the face of the buildings.This work also deals with some aspects in physical properties of four different aggregate construction powder samples such as Moe Hein, Man Thiri, Shwe Taung and Kyauk Sue. In addition, these four different samples were characterized by using spectroscopic methods such as ED-XRF, AAS, FT-IR and XRD. In support of the finding by the analytical assays of Moe Hein aggregate construction powder, it indicated the percent composition of the presence of SiO2 12.13%, Al2O3 7.40%, Fe2O3 0.94%, CaO 41.00%,MgO 1.50% total sulphur 1.15%, chloride 1.49%, carbonate 43.63% and sulphate 3.44%. The analytical assays of Sin Min cement, Kyant cement, brick powder and pozzolan were also carried out in this research work. The mixing between various ratios of Moe Hein and Kyant cement as well as Sin Min II cement were done and their mechanical strengths such as setting time, tensile strength and compressive strength of each sample were studied. The quality of mixing ratio 50:50 of Moe Hein and Kyant cement was found to be comparable to the ASTM standard type II Protland cement which is for general use.

Strength Improvement of Clay Soil by Using Stone Powder

Directory of Open Access Journals (Sweden)

Ahmed Sameer Abdulrasool

2015-05-01

Full Text Available Soil stabilization with stone powder is a good solution for the construction of subgrade for road way and railway lines, especially under the platforms and mostly in transition zones between embankments and rigid structures, where the mechanical properties of supporting soils are very influential. Stone powder often has a unique composition which justifies the need for research to study the feasibility of using this stone powder type for ground improvement applications. This paper presents results from a comprehensive laboratory study carried out to investigate the feasibility of using stone powder for improvement of engineering properties of clays. The stone powder contains bassanite (CaSO4. ½ H2O, and Calcite (CaCO3. Three percentages are used for stone powder (1%, 3% and 5% by dry weight of clay. Several tests are made to investigate the soil behavior after adding the stone powder (Atterberg limits, Standard Proctor density, Grain size distribution, Specific gravity, Unconfined Compressive test, and California bearing ratio test. Unconfined Compressive tests conducted at different curing. The samples are tested under both soaked and unsoaked condition. Chemical tests and X-ray diffraction analyses are also carried out. Stone powder reacts with clay producing decreasing in plasticity and The curves of grain size distribution are shifted to the coarse side as the stone powder percentage increase; the soil becomes more granular, and also with higher strength.

Fear of falling and gait parameters in older adults with and without fall history.

Science.gov (United States)

Makino, Keitaro; Makizako, Hyuma; Doi, Takehiko; Tsutsumimoto, Kota; Hotta, Ryo; Nakakubo, Sho; Suzuki, Takao; Shimada, Hiroyuki

2017-12-01

Fear of falling (FOF) is associated with spatial and temporal gait parameters in older adults. FOF is prevalent among older adults, both those with and without fall history. It is still unclear whether the relationships between FOF and gait parameters are affected by fall history. The aim of the present study was to compare gait parameters by the presence of FOF and fall history. A total of 3575 older adults (mean age 71.7 years, 49.7% female) met the inclusion criteria for the present study. We assessed the presence of fall history and FOF by face-to-face interview, and gait parameters (gait speed, stride length, step rate, double support time and variation of stride length) at a comfortable speed using a computerized electronic walkway. Prevalences of fall history and FOF were as follows: non-fallers without FOF 52.6% (n = 1881); fallers without FOF 6.3% (n = 227); non-fallers with FOF 34.4% (n = 1229); and fallers with FOF 6.7% (n = 238). Analysis of covariance showed significant differences among the four groups in all gait variables even after adjusting for age, sex and number of medications used. It should be noted that non-fallers with FOF showed significantly slower gait speed, shorter stride length and longer double support time than did non-fallers without FOF (P fall history. The assessment of FOF might be helpful for better understanding of age-related changes in gait control. Geriatr Gerontol Int 2017; 17: 2455-2459. © 2017 Japan Geriatrics Society.

Production of rare earth polishing powders in Russia

International Nuclear Information System (INIS)

Kosynkin, V.D.; Ivanov, E.N.; Kotrekhov, V.A.; Shtutza, M.G.; Grabko, A.I.

1998-01-01

Full text: Russia is a potent producer of polishing powders made of rare earth material presented as an extensive and well developed base. Considering the reserves, the facilities predisposition and the polishing agent (cerium dioxide) content the chief mineral source is loparite, apatite and monazite. The production of rare earth polishing powders is based on specially developed continuous technological processes, corrosion-proof equipment, ensuring a high and stable production quality. A special attention is paid to the radiation safety of the powders. The initial material for the rare earth polishing powders based on loparite is the fusion cake of rare earth chlorides obtained at that mineral chlorination. The technology of the polishing powder production from the REE fusion cake includes the following stages: dissolution of the REE fusion cake chlorides; - thorough cleaning of the REE fusion cake chlorides from radioactive and non-rare-earth impurities; chemical precipitation of REE carbonates, obtaining middlings with proper material and granulometric composition, thermal treatment of precipitated carbonates followed with the operations of drying and roasting; classification of roasted oxides, obtaining end products - polishing powders. The production of fluorine-containing powders includes the stage of their fluorination after the stage of carbonate precipitation. The stabilizing doping can be introduced both into the middlings during one of the technological process of powders manufacturing and into the end product. Rare earth polishing powders are manufactured in Russia by the Share Holding Company 'Chepetz Mechanical Plant' (ChMP Co.), the city of Glasov. The plant produces a number of polishing materials, such as; polishing powder Optinol, containing at least 50% by mass of cerium dioxide, used in the mass production of optical and other articles; polishing powder Optinol-10 with doping to improve the sedimentary and aggregate stability of the solid phase

Roller compaction: Effect of relative humidity of lactose powder.

Science.gov (United States)

Omar, Chalak S; Dhenge, Ranjit M; Palzer, Stefan; Hounslow, Michael J; Salman, Agba D

2016-09-01

The effect of storage at different relative humidity conditions, for various types of lactose, on roller compaction behaviour was investigated. Three types of lactose were used in this study: anhydrous lactose (SuperTab21AN), spray dried lactose (SuperTab11SD) and α-lactose monohydrate 200M. These powders differ in their amorphous contents, due to different manufacturing processes. The powders were stored in a climatic chamber at different relative humidity values ranging from 10% to 80% RH. It was found that the roller compaction behaviour and ribbon properties were different for powders conditioned to different relative humidities. The amount of fines produced, which is undesirable in roller compaction, was found to be different at different relative humidity. The minimum amount of fines produced was found to be for powders conditioned at 20-40% RH. The maximum amount of fines was produced for powders conditioned at 80% RH. This was attributed to the decrease in powder flowability, as indicated by the flow function coefficient ffc and the angle of repose. Particle Image Velocimetry (PIV) was also applied to determine the velocity of primary particles during ribbon production, and it was found that the velocity of the powder during the roller compaction decreased with powders stored at high RH. This resulted in less powder being present in the compaction zone at the edges of the rollers, which resulted in ribbons with a smaller overall width. The relative humidity for the storage of powders has shown to have minimal effect on the ribbon tensile strength at low RH conditions (10-20%). The lowest tensile strength of ribbons produced from lactose 200M and SD was for powders conditioned at 80% RH, whereas, ribbons produced from lactose 21AN at the same condition of 80% RH showed the highest tensile strength. The storage RH range 20-40% was found to be an optimum condition for roll compacting three lactose powders, as it resulted in a minimum amount of fines in the

21 CFR 176.350 - Tamarind seed kernel powder.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Tamarind seed kernel powder. 176.350 Section 176... Substances for Use Only as Components of Paper and Paperboard § 176.350 Tamarind seed kernel powder. Tamarind seed kernel powder may be safely used as a component of articles intended for use in producing...

Preparation of potassium-reduced tantalum powders

International Nuclear Information System (INIS)

Kolosov, V.N.; Miroshnichenko, M.N.; Orlov, V.M.; Prokhorova, T.Yu.

2005-01-01

Characteristics of tantalum powders prepared by reduction of molten potassium heptafluorotantalate with liquid potassium are studied in a temperature range of 750 - 850 deg C using potassium chloride as a flux at a ratio of K 2 TaF 7 : KCl = 1, 2, and 3. The use of potassium as a reducing agent facilitates washing of tantalum powders for impurity salt removal, reduces sodium content and leakage currents in the anodes. As compared to sodium process, the potassium reduction results in a high yield of sponge material, a decrease in the specific surface area and yield of tantalum powder suitable for manufacture of capacitor anodes [ru

Determination of the functional properties of Kappaphycus alvarezii seaweed powder

International Nuclear Information System (INIS)

Sjamsiah; Nazaruddin Ramli; Rusli Daik; Mohd Ambar Yarmo

2013-01-01

Seaweed Kappaphycus alvarezii powder prepared by spray drying (SD), freeze drying (FD) and sun drying(SND) were determined their functional properties such as swelling capacity (SWC), water holding capacity (WHC), oil holding capacity (OHC), viscosity and gel strength. The study showed that the Kappaphycus alvarezii seaweed powder obtained by FD and SND have the ability to swell to 25 mL/ g and 50 mL/ g respectively, while the SD powder formed a homogeneous solution and it exhibited highly viscous solution (SWC 100 mL/ g). The WHC of SND powder (30.67 g/ g) was higher (p<0.05) than the FD (21.33 g/ g) and SD (4.67 g/ g) powders. The OHC of FD powder (19.81 g/ g) was higher (p<0.05) than the SD (5.11 g/ g) and SND (4.67 g/ g) powders. While the viscosity of the FD, SND and SD powders were 0.22, 0.17 and 0.06 Pa.s respectively. Meanwhile, the gel strength of the SD powder (82.77 gf) was higher (p<0.05) than the FD (57.1 gf) and SND (35.01 gf) powders. These results on determination of functional properties shows that the SD powder had the most potential to be applied as a viscosity modifier in the manufacturing of beverages.(author)

Does functional capacity, fall risk awareness and physical activity level predict falls in older adults in different age groups?

Science.gov (United States)

Moreira, Natália Boneti; Rodacki, Andre Luiz Felix; Pereira, Gléber; Bento, Paulo Cesar Barauce

2018-04-11

The aims of this study were to examine whether: i) functional capacity and physical activity level differ between fallers and non-fallers older adults, by controlling for fall risk awareness; ii) functional capacity, fall risk awareness and physical activity differ between fallers and non-fallers older adults, by controlling for age; iii) variables and which may predict falls in different age groups. 1826 older adults performed a series of functional tests and reported their fall episodes, fall risk awareness and physical activity level. The overall incidence of falls was high (40.2%), and falls risk awareness scores reduced with age. The older adults with greater falls risk awareness and non-fallers presented better scores in all functional tests and physical activity level (P age groups and differed between fallers and non-fallers, irrespective of age group (P age groups (odds ranging: 1.05-1.09). Handgrip strength and balance scores predicted falls until 79 years (OR = 1.04, 95%CI = 1.01-1.06). The physical activity level predicted falls up to 70 years (OR = 1.09, 95%CI = 1.06-1.12). Functional mobility was able to predict falls up to 80 years (OR = 1.06, 95%CI = 1.01-1.08). Therefore, according to age, functional capacity, physical activity level and falls risk awareness can be a predictor of falls in older adults. Copyright © 2018 Elsevier B.V. All rights reserved.

Effects of Powder Attributes and Laser Powder Bed Fusion (L-PBF) Process Conditions on the Densification and Mechanical Properties of 17-4 PH Stainless Steel

Science.gov (United States)

Irrinki, Harish; Dexter, Michael; Barmore, Brenton; Enneti, Ravi; Pasebani, Somayeh; Badwe, Sunil; Stitzel, Jason; Malhotra, Rajiv; Atre, Sundar V.

2016-03-01

The effects of powders attributes (shape and size distribution) and critical processing conditions (energy density) on the densification and mechanical properties of laser powder bed fusion (L-PBF) 17-4 PH stainless steel were studied using four types of powders. The % theoretical density, ultimate tensile strength and hardness of both water- and gas-atomized powders increased with increased energy density. Gas-atomized powders showed superior densification and mechanical properties when processed at low energy densities. However, the % theoretical density and mechanical properties of water-atomized powders were comparable to gas-atomized powders when sintered at a high energy density of 104 J/mm3. An important result of this study was that, even at high % theoretical density (97% ± 1%), the properties of as-printed parts could vary over a relatively large range (UTS: 500-1100 MPa; hardness: 25-39 HRC; elongation: 10-25%) depending on powder characteristics and process conditions. The results also demonstrate the feasibility of using relatively inexpensive water-atomized powders as starting raw material instead of the typically used gas-atomized powders to fabricate parts using L-PBF techniques by sintering at high energy densities.

Preparation of cerium oxide for lens polishing powder

International Nuclear Information System (INIS)

Injarean, Uthaiwan; Rodthongkom, Chouvana; Pichestapong, Pipat; Changkrurng, Kalaya

2003-10-01

Cerium is an element of rare earth group which is called lanthanide series. It is found in the ores like monazite and xenotime which are the tailings of tin mines in the south of Thailand. Cerium is used mostly as lens polishing powder besides the applications in other industries. In this study, cerium extracted from monazite ore breakdown by alkaline process was used for the preparation of lens polishing powder. Cerium hydroxide cake from the process was dissolved by hydrochloric acid and precipitated with oxalic acid. The oxalate precipitate then was calcined to oxide powder and its particle size was measured. Precipitation conditions being studied are concentration of feed cerium chloride solution, concentration of oxalic acid used for the precipitation, concentration of sulfuric acid used as precipitation control reagent and the precipitation temperature. It was found that the appropriate precipitation conditions yielded the fine oxide powder with particle size about 12μm. The oxide powder can be ground to the size of 1-3 μm which is suitable for making lens polishing powder

21 CFR 73.1646 - Bronze powder.

Science.gov (United States)

2010-04-01

... percent. Maximum particle size 45µ (95 percent minimum). Aluminum, zinc, tin, and copper content shall be based on the weight of the dried powder after being thoroughly washed with ether. (c) Uses and restrictions. Bronze powder may be safely used in color externally applied drugs, including those intended for...

Hydrothermal synthesis of fine oxide powders

Indian Academy of Sciences (India)

Unknown

Inorganic powders are among the most important factors in many fields of materials such as ceramics, catalysts, medicines, food, etc. There are many papers and books related to powders preparation by many authors (Veale. 1972; Kato and Yamaguchi 1983; Vincenzini 1983;. Brinker et al 1984; Johnson Jr. 1987; Messing ...