WorldWideScience

Sample records for isolated tail flexion

  1. DNA isolation from rat tail or ear

    NARCIS (Netherlands)

    Cuppen, E.

    2010-01-01

    This protocol describes a rapid procedure for isolating DNA from rat tail or ear punches. The simplest version of the protocol can be scaled for use in 96-well (deep-well) plates. The quality of the DNA is sufficient for any polymerase chain reaction (PCR)-based genotyping approach.

  2. Isolated flexor pollicis longus nerve fascicle lesion – a rare differential diagnosis of thumb flexion deficiency

    Directory of Open Access Journals (Sweden)

    Glauser, Eva

    2016-12-01

    Full Text Available A rare differential diagnosis of thumb flexion deficiency is an isolated flexor pollicis longus (FPL nerve fascicle lesion. We present a 42-year-old otherwise healthy female patient who developed a weak thumb-to-index pinch and deficient right thumb flexion following the removal of osteosynthesis plates after a forearm fracture. Clinically,the flexor pollicis longus function was absent, yet index flexion and sensibility were unimpaired. Tendon rupture was excluded using a tenodesis test and the electro-physiological result of isolated interosseus nerve fascicle lesion was confirmed intraoperatively by inspection and electrostimulation. Tendon transfer using the extensor carpi radialis longus reconstruct strong thumb flexion during pinch. In summary, due to its specific location and anatomy, the FPL branch is more prone to isolated neuropathy, e.g. by injections or operations, than to other fascicles of the anterior interosseus nerve. When confronted with sudden and isolated thumb flexion deficiency, specialists should be aware of this rare phenomenon.

  3. Treatable Bedridden Elderly―Recovery from Flexion Contracture after Cortisol Replacement in a Patient with Isolated Adrenocorticotropic Hormone Deficiency

    Science.gov (United States)

    Tanaka, Takamasa; Terada, Norihiko; Fujikawa, Yoshiki; Fujimoto, Takushi

    2016-01-01

    Isolated adrenocorticotropic hormone deficiency (IAD) is a rare disorder with diverse clinical presentations. A 79-year-old man was bedridden for six months due to flexion contractures of the bilateral hips and knees, along with hyponatremia. He was diagnosed with IAD based on the results of endocrine tests. After one month of corticosteroid replacement, he recovered and was able to stand up by himself. Although flexion contracture is a rare symptom of IAD, steroid replacement therapy may be effective, even for seemingly irreversibly bedridden elderly patients. In bedridden elderly patients with flexion contractures, we should consider and look for any signs of adrenal insufficiency. PMID:27746435

  4. Treatable Bedridden Elderly -Recovery from Flexion Contracture after Cortisol Replacement in a Patient with Isolated Adrenocorticotropic Hormone Deficiency.

    Science.gov (United States)

    Tanaka, Takamasa; Terada, Norihiko; Fujikawa, Yoshiki; Fujimoto, Takushi

    Isolated adrenocorticotropic hormone deficiency (IAD) is a rare disorder with diverse clinical presentations. A 79-year-old man was bedridden for six months due to flexion contractures of the bilateral hips and knees, along with hyponatremia. He was diagnosed with IAD based on the results of endocrine tests. After one month of corticosteroid replacement, he recovered and was able to stand up by himself. Although flexion contracture is a rare symptom of IAD, steroid replacement therapy may be effective, even for seemingly irreversibly bedridden elderly patients. In bedridden elderly patients with flexion contractures, we should consider and look for any signs of adrenal insufficiency.

  5. Reactivity of the isolated perfused rat tail vascular bed

    Directory of Open Access Journals (Sweden)

    A.S. França

    1997-07-01

    Full Text Available Isolated segments of the perfused rat tail artery display a high basal tone when compared to other isolated arteries such as the mesenteric and are suitable for the assay of vasopressor agents. However, the perfusion of this artery in the entire tail has not yet been used for functional studies. The main purpose of the present study was to identify some aspects of the vascular reactivity of the rat tail vascular bed and validate this method to measure vascular reactivity. The tail severed from the body was perfused with Krebs solution containing different Ca2+ concentrations at different flow rates. Rats were anesthetized with sodium pentobarbital (65 mg/kg and heparinized (500 U. The tail artery was dissected near the tail insertion, cannulated and perfused with Krebs solution plus 30 µM EDTA at 36oC and 2.5 ml/min and the procedures were started after equilibration of the perfusion pressure. In the first group a dose-response curve to phenylephrine (PE (0.5, 1, 2 and 5 µg, bolus injection was obtained at different flow rates (1.5, 2.5 and 3.5 ml/min. The mean perfusion pressure increased with flow as well as PE vasopressor responses. In a second group the flow was changed (1.5, 2, 2.5, 3 and 3.5 ml/min at different Ca2+ concentrations (0.62, 1.25, 2.5 and 3.75 mM in the Krebs solution. Increasing Ca2+ concentrations did not alter the flow-pressure relationship. In the third group a similar protocol was performed but the rat tail vascular bed was perfused with Krebs solution containing PE (0.1 µg/ml. There was an enhancement of the effect of PE with increasing external Ca2+ and flow. PE vasopressor responses increased after endothelial damage with air and CHAPS, suggesting an endothelial modulation of the tone of the rat tail vascular bed. These experiments validate the perfusion of the rat tail vascular bed as a method to investigate vascular reactivity

  6. Behaviour of tail-docked lambs tested in isolation

    Directory of Open Access Journals (Sweden)

    Marchewka Joanna

    2016-12-01

    Full Text Available The aims of the current study were to detect behavioural indicators of pain of tail-docked sheep tested in isolation and to determine the relationship between behaviour and the pain levels to which they were exposed. Twenty-four female lambs, randomly assigned to four pens, had their tail docked with a rubber ring (TD; n = 6 without pain control procedures, TD with anaesthesia (TDA; n = 6 or TD with anaesthesia and analgesia (TDAA; n = 6. Additionally, six lambs handled but without tail docking or application of pain relief measures were used as the control (C. On the day prior (Day –1 to the TD and on days 1, 3 and 5 post-procedure, each lamb was individually removed from its group and underwent a 2.5 min open field test in a separate pen. Frequencies of behaviours such as rest, running, standing, walking and exploring were directly observed. Frequencies of exploratory climbs (ECs and abrupt climbs (ACs over the testing pen’s walls were video-recorded. Data were analysed using generalised linear mixed models with repeated measurements, including treatment and day as fixed effects and behaviour on Day –1 as a linear covariate. Control and TDAA lambs stood more frequently than TD lambs. TD lambs performed significantly more ACs compared to all other treatment groups. No other treatment effects were detected. A day effect was detected for all behaviours, while the EC frequency was highest for all tail-docked lambs on Day 5. Findings suggest that standing, ACs and ECs could be used as potential indicators of pain in isolated tail-docked lambs. However, differences in ECs between treatments only appeared 3 d after tail docking.

  7. Biosorption of Zinc (Zn) and lead (Pb) by metal resistant bacterial isolate from mining tail

    Energy Technology Data Exchange (ETDEWEB)

    Bautista Hernandez, D. A.; Carranza Alvarado, M.; Fernandez Linares, L.; Ramirez Landy, I.

    2009-07-01

    The use of microbial biomass in the removal of metals in solution, mainly of low concentrations (100 mg L{sup -}1), present advantages in relation to the physicochemical methods. The resistant microorganisms are potential bio sorbents. The objective of the present study was the isolation, starting from mining tail, of strains with capacity of metal bio sorption (Zn and Pb). (Author)

  8. Biosorption of Zinc (Zn) and lead (Pb) by metal resistant bacterial isolate from mining tail

    International Nuclear Information System (INIS)

    Bautista Hernandez, D. A.; Carranza Alvarado, M.; Fernandez Linares, L.; Ramirez Landy, I.

    2009-01-01

    The use of microbial biomass in the removal of metals in solution, mainly of low concentrations (100 mg L - 1), present advantages in relation to the physicochemical methods. The resistant microorganisms are potential bio sorbents. The objective of the present study was the isolation, starting from mining tail, of strains with capacity of metal bio sorption (Zn and Pb). (Author)

  9. Stability of multilayer earthen barriers used to isolate mill tailings: geologic and geotechnological considerations

    International Nuclear Information System (INIS)

    Zellmer, J.T.

    1981-08-01

    This report briefly discusses how seismic activity, erosion, climatic change, slope stability, differential settlement, and cover design could affect the long-term integrity of multilayer earthen cover systems. In addition, the report suggests ways to design and construct covers so that adverse impacts can be avoided or minimized. The stability of multilayer earthen barriers used to isolate uranium mill tailings depends on the morphology of the disposal site, the engineering of the barrier, the condition of the tailings, and the possible impacts of earthquakes, erosion, and climatic changes. When designing a cover for or siting a tailings pile, one must take into account both geologic and geotechnological variables. To alleviate the adverse effects of possible seismic activity, tailings piles should never be located on or near active or capable faults. Existing piles near faults should be moved to safer sites or engineered to withstand possible displacement and shaking. Liquefaction generally can be prevented if the tailings and their underlying material are compacted to a relative density of 60% or greater, or if they are kept dry. If the tailings are saturated, dewatering schemes may have to be used. Erosion may be caused by streams, glaciers, or wind, depending on the geomorphic and atmospheric conditions at the site. Fluvial erosion can be prevented by using dikes (and avoided by initially siting the pile a safe distance away from stream courses). In some cases, fluvial waters or rainfall may have to be rerouted over the pile via armored ditches. Eolian erosion can be minimized by vegetating the disposal site or covering it with gravel. Because of the wide geomorphic and geotechnological variations extant at most sites, a single cover design cannot be cost-effectively and efficiently used at all sites

  10. Stability of multilayer earthen barriers used to isolate mill tailings: geologic and geotechnological considerations

    Energy Technology Data Exchange (ETDEWEB)

    Zellmer, J.T.

    1981-08-01

    This report briefly discusses how seismic activity, erosion, climatic change, slope stability, differential settlement, and cover design could affect the long-term integrity of multilayer earthen cover systems. In addition, the report suggests ways to design and construct covers so that adverse impacts can be avoided or minimized. The stability of multilayer earthen barriers used to isolate uranium mill tailings depends on the morphology of the disposal site, the engineering of the barrier, the condition of the tailings, and the possible impacts of earthquakes, erosion, and climatic changes. When designing a cover for or siting a tailings pile, one must take into account both geologic and geotechnological variables. To alleviate the adverse effects of possible seismic activity, tailings piles should never be located on or near active or capable faults. Existing piles near faults should be moved to safer sites or engineered to withstand possible displacement and shaking. Liquefaction generally can be prevented if the tailings and their underlying material are compacted to a relative density of 60% or greater, or if they are kept dry. If the tailings are saturated, dewatering schemes may have to be used. Erosion may be caused by streams, glaciers, or wind, depending on the geomorphic and atmospheric conditions at the site. Fluvial erosion can be prevented by using dikes (and avoided by initially siting the pile a safe distance away from stream courses). In some cases, fluvial waters or rainfall may have to be rerouted over the pile via armored ditches. Eolian erosion can be minimized by vegetating the disposal site or covering it with gravel. Because of the wide geomorphic and geotechnological variations extant at most sites, a single cover design cannot be cost-effectively and efficiently used at all sites.

  11. Heavy Metal Tolerance and Removal Capacity of Trichoderma species Isolated from Mine Tailings in Itogon, Benguet

    Directory of Open Access Journals (Sweden)

    Myra Tansengco

    2017-11-01

    Full Text Available Waste from mining industries contains various heavy metals that can pollute the environment. Bioremediation using efficient fungi can help in eliminating these heavy metal contaminants. This study focused on the isolation, identification, and characterization of heavy metal-resistant fungi from mine tailings in Itogon, Benguet. Isolation of fungi was done by serial dilution and spread plate techniques on potato dextrose agar (PDA with an individual heavy metal, i.e. chromium (Cr, copper (Cu, lead (Pb, zinc (Zn, and nickel (Ni. Of the 29 fungal isolates, four species were selected and molecularly identified as Trichoderma virens, T. harzianum, T. saturnisporum, and T. gamsii. Growth tolerance on PDA with increasing concentrations (200-1000 ppm of an individual heavy metal indicated the following trend: T. virens > T. harzianum > T. gamsii > T. saturnisporum. Growth test indicates that all Trichoderma isolates can tolerate high levels of Cr and Pb, however tolerance to Cu, Zn, and Ni was species specific. Shakeflask culture using T. virens showed high lead removal (91-96% over broad pH range while and at neutral pH, T. virens had 70% and 63% reductions for Cu and Cr, respectively. Results of this study highlights the potential of Trichoderma isolates for biological wastewater treatment in mining industries.

  12. Engineering solutions to the long-term stabilization and isolation of uranium mill tailings in the United States

    International Nuclear Information System (INIS)

    Sanders, D.R.; Lommler, J.C.

    1995-01-01

    Engineering solutions to the safe and environmentally protective disposal and isolation of uranium mill tailings in the US include many factors. Cover design, materials selection, civil engineering, erosive forces, and cost effectiveness are only a few of those factors described in this paper. The systems approach to the engineering solutions employed in the US is described, with emphasis on the standards prescribed for the Uranium Mill Tailings Remedial Action Project. Stabilization and isolation of the tailings from humans and the environment are the primary goals of the US uranium mill tailings control standards. The performance of cover designs with respect to water infiltration, radon exhalation, geotechnical stability, erosion protection, human and animal intrusion prevention, and longevity are addressed. The need for and frequency of surveillance efforts to ensure continued disposal system performance are also assessed

  13. Mycobacterium hippocampi sp. nov., a rapidly growing scotochromogenic species isolated from a seahorse with tail rot.

    Science.gov (United States)

    Balcázar, José Luis; Planas, Miquel; Pintado, José

    2014-09-01

    A Gram-positive, aerobic, non-motile, non-sporulating, acid-fast, and rod-shaped bacterium (BFLP-6(T)), previously isolated from a seahorse (Hippocampus guttulatus) with tail rot, was studied using a polyphasic taxonomic approach. Growth occurred at 15-35 °C (optimum 25 °C), at pH 5.0-10.0 (optimum pH 7.0) and at NaCl concentrations between 0 and 6 % (w/v). The G+C content of DNA was 66.7 mol%. The predominant fatty acids were C(18:1) ω9c, C(16:0) and C(16:1) ω6c. A mycolic acid pattern of alpha-mycolates and keto-mycolates was detected. Analysis of concatenated sequences (16S rRNA, rpoB, ssrA and tuf genes), and chemotaxonomic and phenotypic features indicated that strain BFLP-6(T) represents a novel species within the genus Mycobacterium, for which the name Mycobacterium hippocampi sp. nov. is proposed. The type strain is BFLP-6(T) (=DSM 45391(T) =LMG 25372(T)).

  14. Flexion in Abell 2744

    Science.gov (United States)

    Bird, J. P.; Goldberg, D. M.

    2018-05-01

    We present the first flexion-focused gravitational lensing analysis of the Hubble Frontier Field observations of Abell 2744 (z = 0.308). We apply a modified Analytic Image Model technique to measure source galaxy flexion and shear values at a final number density of 82 arcmin-2. By using flexion data alone, we are able to identify the primary mass structure aligned along the heart of the cluster in addition to two major substructure peaks, including an NE component that corresponds to previous lensing work and a new peak detection offset 1.43 arcmin from the cluster core towards the east. We generate two types of non-parametric reconstructions: flexion aperture mass maps, which identify central core, E, and NE substructure peaks with mass signal-to-noise contours peaking at 3.5σ, 2.7σ, and 2.3σ, respectively; and convergence maps derived directly from the smoothed flexion field. For the primary peak, we find a mass of (1.62 ± 0.12) × 1014 h-1 M⊙ within a 33 arcsec (105 h-1 kpc) aperture, a mass of (2.92 ± 0.26) × 1013 h-1 M⊙ within a 16 arcsec (50 h-1 kpc) aperture for the north-eastern substructure, and (8.81 ± 0.52) × 1013 h-1 M⊙ within a 25 arcsec (80 h-1 kpc) aperture for the novel eastern substructure.

  15. Application of a double-enrichment procedure for microsatellite isolation and the use of tailed primers for high throughput genotyping

    Directory of Open Access Journals (Sweden)

    Fábio Mendonça Diniz

    2007-03-01

    Full Text Available The number of microsatellite loci and their allelic diversity contribute to increase accuracy and informativity of genetic estimates, however, the isolation of microsatellite loci is not only laborious but also quite expensive. We used (GATAn and (GACAn tetranucleotide probes and single- and double-enrichment hybridization to construct and screen a genomic library with an increased proportion of DNA fragments containing repeat motifs. Repeats were found using both types of hybridization but the double-enrichment procedure recovered sequences of which 100% contained (GATAn and (GACAn motifs. Microsatellite loci primers were then designed with an M13R-tail or CAG-tag to produce scorable PCR products with minimal stutter. The approach used in this study suggests that double-enrichment is a worthwhile strategy when isolating repeat motifs from eukaryotic genomes. Moreover, the use of tailed microsatellite primers provides increased resolution for compound microsatellite loci, with a significant decrease in costs.

  16. The Effect of Upper Body Mass and Initial Knee Flexion on the Injury Outcome of Post Mortem Human Subject Pedestrian Isolated Legs.

    Science.gov (United States)

    Petit, Philippe; Trosseille, Xavier; Dufaure, Nicolas; Dubois, Denis; Potier, Pascal; Vallancien, Guy

    2014-11-01

    In the ECE 127 Regulation on pedestrian leg protection, as well as in the Euro NCAP test protocol, a legform impactor hits the vehicle at the speed of 40 kph. In these tests, the knee is fully extended and the leg is not coupled to the upper body. However, the typical configuration of a pedestrian impact differs since the knee is flexed during most of the gait cycle and the hip joint applies an unknown force to the femur. This study aimed at investigating the influence of the inertia of the upper body (modelled using an upper body mass fixed at the proximal end of the femur) and the initial knee flexion angle on the lower limb injury outcome. In total, 18 tests were conducted on 18 legs from 9 Post Mortem Human Subjects (PMHS). The principle of these tests was to impact the leg at 40 kph using a sled equipped with 3 crushing steel tubes, the stiffness of which were representative of the front face of a European sedan (bonnet leading edge, bumper and spoiler). The mass of the equipped sled was 74.5 kg. The test matrix was designed to perform 4 tests in 4 configurations combining two upper body masses (either 0 or 3 kg) and two knee angles (0 or 20 degrees) at 40 kph (11 m/s) plus 2 tests at 9 m/s. Autopsies were performed on the lower limbs and an injury assessment was established. The findings of this study were first that the increase of the upper body mass resulted in more severe injuries, second that an initial flexion of the knee, corresponding to its natural position during the gait cycle, decreased the severity of the injuries, and third that based on the injury outcome, a test conducted with no upper body mass and the knee fully extended was as severe as a test conducted with a 3 kg upper body mass and an initial knee flexion of 20°.

  17. Isolation of uranium mill tailings and their component radionuclides from the biosphere; some earth science perspectives

    Science.gov (United States)

    Landa, Edward

    1980-01-01

    Uranium mining and milling is an expanding activity in the. Western United States. Although the milling process yields a uranium concentrate, the large volume of tailings remaining contains about 85 percent of the radioactivity originally associated with the ore. By virtue of the physical and chemical processing of the ore and the redistribution of the contained radionuclides at the Earth's surface, these tailings constitute a technologically enhanced source of natural radiation exposure. Sources of potential human radiation exposure from uranium mill tailings include the emanation of radon gas, the transport of particles by wind and water, and the transport of soluble radionuclides, seeping from disposal areas, by ground water. Due to the 77,000 year half-life of thorium-230, the parent of radium-226, the environmental effects associated with radionuclides contained in these railings must be conceived of within the framework of geologic processes operating over geologic time. The magnitude of erosion of cover materials and tailings and the extent of geochemical mobilization of the contained radionuclides to the atmosphere and hydrosphere should be considered in the evaluation of the potential, long-term consequences of all proposed uranium mill tailings management plans.

  18. Benefit-cost aspects of long-term isolation of uranium mill tailings

    International Nuclear Information System (INIS)

    Van Dyke, J.

    1983-11-01

    The Uranium Mill Tailings Radiation Control Act of 1978 provides for regulations for control of radon diffusion from uranium mill tailings to protect the public welfare. In developing these regulations, the Office of Nuclear Material Safety and Safeguards of the Nuclear Regulatory Commission has sought to establish the benefits and costs for alternative regulatory criteria. This report provides a perspective on some economic issues associated with long-term radiation effects from disposal of uranium mill tailings. The general problem of developing an economic rationale for regulating this activity is complicated by the very long-term and widespread effects which could result from radon gas diffusion associated with tailings piles. The economic issues are also complex because of the trade-offs between costs of disposal and intangible social values. When intergenerational implications were considered the traditional basis for discounting in a benefit-cost framework was found to shift. The appropriate rate of discount was found to depend on ethical assumptions and expectations about the relative welfare of future generations. 30 references, 1 figure, 2 tables

  19. Benefit-cost aspects of long-term isolation of uranium mill tailings

    Energy Technology Data Exchange (ETDEWEB)

    Van Dyke, J.

    1983-11-01

    The Uranium Mill Tailings Radiation Control Act of 1978 provides for regulations for control of radon diffusion from uranium mill tailings to protect the public welfare. In developing these regulations, the Office of Nuclear Material Safety and Safeguards of the Nuclear Regulatory Commission has sought to establish the benefits and costs for alternative regulatory criteria. This report provides a perspective on some economic issues associated with long-term radiation effects from disposal of uranium mill tailings. The general problem of developing an economic rationale for regulating this activity is complicated by the very long-term and widespread effects which could result from radon gas diffusion associated with tailings piles. The economic issues are also complex because of the trade-offs between costs of disposal and intangible social values. When intergenerational implications were considered the traditional basis for discounting in a benefit-cost framework was found to shift. The appropriate rate of discount was found to depend on ethical assumptions and expectations about the relative welfare of future generations. 30 references, 1 figure, 2 tables.

  20. Galaxies with long tails

    International Nuclear Information System (INIS)

    Schweizer, F.

    1978-01-01

    Two types of galaxies with long tails are described. The first occurs in pairs, each individual one having a long tail and the second occurs on its own with two tails. NGC 7252 shows several characteristics which one would expect of a merger: a pair of tidal tails despite the splendid isolation, a single nucleus, tail motions in opposite directions relative to the nucleus, and chaotic motions of a strangely looped main body. (C.F.)

  1. Isolation and characterization of lost copper and molybdenum particles in the flotation tailings of Kennecott copper porphyry ores

    Science.gov (United States)

    Tserendavga, Tsend-Ayush

    The importance of flotation separation has long been, and continues to be, an important technology for the mining industry, especially to metallurgical engineers. However, the flotation process is quite complex and expensive, in addition to being influenced by many variables. Understanding the variables affecting flotation efficiency and how valuable minerals are lost to the tailings gives metallurgists an advantage in their attempts to increase efficiency by designing operations to target the areas of greatest potential value. A successful, accurate evaluation of lost minerals in the tailings and appropriate solutions to improve flotation efficiency can save millions of dollars in the effective utilization of our mineral resources. In this dissertation research, an attempt has been made to understand the reasons for the loss of valuable mineral particles in the tailings from Kennecott Utah Copper ores. Possibilities include liberation, particle aggregation (slime coating) and surface chemistry issues associated with the flotation separation. This research generally consisted of three main aspects. The first part involved laboratory flotation experiments and factors, which affect the flotation efficiency. Results of flotation testing are reported that several factors such as mineral exposure/liberation and slime coating and surface oxidation strongly affect the flotation efficiency. The second part of this dissertation research was to develop a rapid scan dual energy (DE) methodology using 2D radiography to identify, isolate, and prepare lost sulfide mineral particles with the advantages of simple sample preparation, short analysis time, statistically reliable accuracy and confident identification. The third part of this dissertation research was concerned with detailed characterization of lost particles including such factors as liberation, slime coating, and surface chemistry characteristics using advanced analytical techniques and instruments. Based on the

  2. Isolation and characterization of the heavy metal resistant bacteria CCNWRS33-2 isolated from root nodule of Lespedeza cuneata in gold mine tailings in China

    International Nuclear Information System (INIS)

    Wei Gehong; Fan Lianmei; Zhu Wenfei; Fu Yunyun; Yu Jianfu; Tang Ming

    2009-01-01

    A total of 108 strains of bacteria were isolated from root nodules of wild legumes growing in gold mine tailings in northwest of China and were tested for heavy metal resistance. The results showed that the bacterial strain CCNWRS33-2 isolated from Lespedeza cuneata was highly resistant to copper, cadmium, lead and zinc. The strain had a relatively high mean specific growth rate under each heavy metal stress test and exhibited a high degree of bioaccumulation ability. The partial sequence of the copper resistance gene copA was amplified from the strain and a sequence comparison with our Cu-resistant PCR fragment showed a high homology with Cu-resistant genes from other bacteria. Phylogenetic analysis based on the 16S rRNA gene sequence showed that CCNWRS33-2 belongs to the Rhizobium-Agrobacterium branch and it had 98.9% similarity to Agrobactrium tumefaciens LMG196

  3. Isolation and characterization of the heavy metal resistant bacteria CCNWRS33-2 isolated from root nodule of Lespedeza cuneata in gold mine tailings in China

    Energy Technology Data Exchange (ETDEWEB)

    Wei Gehong [College of Life Science, Shaanxi Key Laboratory of Molecular Biology for Agriculture, Northwest A and F University, Yangling Shaanxi 712100 (China)], E-mail: weigehong@yahoo.com.cn; Fan Lianmei; Zhu Wenfei; Fu Yunyun; Yu Jianfu; Tang Ming [College of Life Science, Shaanxi Key Laboratory of Molecular Biology for Agriculture, Northwest A and F University, Yangling Shaanxi 712100 (China)

    2009-02-15

    A total of 108 strains of bacteria were isolated from root nodules of wild legumes growing in gold mine tailings in northwest of China and were tested for heavy metal resistance. The results showed that the bacterial strain CCNWRS33-2 isolated from Lespedeza cuneata was highly resistant to copper, cadmium, lead and zinc. The strain had a relatively high mean specific growth rate under each heavy metal stress test and exhibited a high degree of bioaccumulation ability. The partial sequence of the copper resistance gene copA was amplified from the strain and a sequence comparison with our Cu-resistant PCR fragment showed a high homology with Cu-resistant genes from other bacteria. Phylogenetic analysis based on the 16S rRNA gene sequence showed that CCNWRS33-2 belongs to the Rhizobium-Agrobacterium branch and it had 98.9% similarity to Agrobactrium tumefaciens LMG196.

  4. Biological removal of sulfur from coal flotation concentrate by culture isolated from coal washery plant tailing dump

    Energy Technology Data Exchange (ETDEWEB)

    Jorjani, E. [Azad University, Tehran (Iran). Mining Engineering Dept.

    2005-10-15

    A combination of flotation and microbial leaching processes was used to achieve acceptable level of sulfur and ash in Tabas coal sample of Iran. Representative sample of the minus 500 micron size fraction was subjected to flotation separation for the removal of ash and sulfur. The final concentrate with recovery, combustion value and sulfur content of 86.03, 86.45 and 1.35% respectively was achieved at pH 8 and following reagent dosage and operating conditions: collector: diesel oil (1200 g/ton), frother: MIBC (5%) + pine oil (95%) with concentration of 120 (g/ton), depressant: sodium silicate (1000 g/ton), particle size: {lt} 500 {mu} m and pulp density: 7%. Because of fine distribution of sulfur on Tabas coal macerals and lithotypes, high percentage of total sulfur (79.9%) is distributed in flotation concentrate and only 20.1% is yielded in the tails. So microbial leaching using a species isolated from coal washery plant tailing dump was used in batch system to remove sulfur from flotation concentrate. The conditions were optimized for the maximum removal of sulfur. These conditions were found to be pH of 2, particle size less than 0.18 mm; pulp density: 8%, temperature: 30 {sup o}C, shaking rate: 150 rpm conditions. Total sulfur and ash content was reduced by bioleaching from 13.55 and 1.35 in flotation concentrate to 9.47 and 0.55 in the final leached concentrate, a reduction of 35 and 61.9% respectively. Sterilization of coal adversely affects the sulfur reduction. The results suggest that the isolated culture is sufficiently effective for depyritization of Tabas coal flotation concentrate in stirred system.

  5. Spine lateral flexion strength development differences between exercises with pelvic stabilization and without pelvic stabilization

    Science.gov (United States)

    Straton, Alexandru; Gidu, Diana Victoria; Micu, Alexandru

    2015-02-01

    Poor lateral flexor muscle strength can be an important source of lumbar/thoracic back pain in women. The purpose of this study was to evaluate pelvic stabilization (PS) and no pelvic stabilization (NoPS) lateral flexion strength exercise training on the development of isolated right and left lateral flexion strength. Isometric torque of the isolated right and left lateral flexion muscles was measured at two positions (0° and 30° opposed angle range of motion) on 42 healthy women before and after 8 weeks of PS and NoPS lateral flexion strength exercise training. Subjects were assigned in three groups, the first (n=14) trained 3 times/week with PS lateral flexion strength exercise, the second (n=14) trained 3 times/week with NoPS lateral flexion strength exercise and the third (control, n=14) did not train. Post training isometric strength values describing PS and NoPS lateral flexion strength improved in greater extent for the PS lateral flexion strength exercise group and in lesser extent for the NoPS lateral flexion strength exercise group, in both angles (pstrength exercises; NoPS lateral flexion strength exercises can be an effective way of training for the spine lateral flexion muscles, if there is no access to PS lateral flexion strength training machines.

  6. Selection and geographic isolation influence hummingbird speciation: genetic, acoustic and morphological divergence in the wedge-tailed sabrewing (Campylopterus curvipennis

    Directory of Open Access Journals (Sweden)

    Ornelas Juan

    2011-02-01

    Full Text Available Abstract Background Mesoamerica is one of the most threatened biodiversity hotspots in the world, yet we are far from understanding the geologic history and the processes driving population divergence and speciation for most endemic taxa. In species with highly differentiated populations selective and/or neutral factors can induce rapid changes to traits involved in mate choice, promoting reproductive isolation between allopatric populations that can eventually lead to speciation. We present the results of genetic differentiation, and explore drift and selection effects in promoting acoustic and morphological divergence among populations of Campylopterus curvipennis, a lekking hummingbird with an extraordinary vocal variability across Mesoamerica. Results Analyses of two mitochondrial genes and ten microsatellite loci genotyped for 160 individuals revealed the presence of three lineages with no contemporary gene flow: C. c. curvipennis, C. c. excellens, and C. c. pampa disjunctly distributed in the Sierra Madre Oriental, the Tuxtlas region and the Yucatan Peninsula, respectively. Sequence mtDNA and microsatellite data were congruent with two diversification events: an old vicariance event at the Isthmus of Tehuantepec (c. 1.4 Ma, and a more recent Pleistocene split, isolating populations in the Tuxtlas region. Hummingbirds of the excellens group were larger, and those of the pampa group had shorter bills, and lineages that have been isolated the longest shared fewer syllables and differed in spectral and temporal traits of a shared syllable. Coalescent simulations showed that fixation of song types has occurred faster than expected under neutrality but the null hypothesis that morphological divergence resulted from drift was not rejected. Conclusions Our phylogeographic analyses uncovered the presence of three Mesoamerican wedge-tailed sabrewing lineages, which diverged at different time scales. These results highlight the importance of the

  7. Improved knee flexion following high-flexion total knee arthroplasty

    Directory of Open Access Journals (Sweden)

    Lionberger David R

    2012-06-01

    Full Text Available Abstract Background The application of new techniques and materials in total knee arthroplasty (TKA continue to be a primary focus in orthopedic surgery. The primary aim of the present study is to evaluate post TKA total range of motion (ROM among a group of patients who received a gender specific high-flexion design modification implant compared to a control group of patients who received non-gender specific implants. Methods and results The control group was comprised of 39 TKAs that were recruited pre-operatively and received the non-gender specific implant while the study group consisted of 39 TKAs who received gender specific implants. The study group yielded an improvement in mean post-operative ROM of 21° at 12 months, whereas the mean improvement in ROM among the control group was 11°. Thus, the study group had a 10° increased ROM improvement (91% over the control group (p = 0.00060. In addition, 100% of the subjects with gender specific high-flexion implants achieved greater or equal ROM post-operatively compared to 82% for the control cohort. Lastly, women who exhibited greater pre-operative ROM and lower body mass index (BMI were found to benefit the most with the gender specific prosthesis. Conclusion Our study demonstrates that among subjects with a normal BMI, the gender specific high-flexion knee implant is associated with increased ROM as compared to the non-gender specific non-high-flexion implant designs.

  8. Infection of human and non-human cells by a highly fusogenic primary CD4-independent HIV-1 isolate with a truncated envelope cytoplasmic tail

    International Nuclear Information System (INIS)

    Saha, Kunal; Yan Hui; Nelson, Julie A.E.; Zerhouni-Layachi, Bouchra

    2005-01-01

    Truncation of the envelope cytoplasmic tail has enabled FIV, SIV, and some laboratory HIV-1 strains to acquire broader cellular tropism and enhanced fusogenicity. Here we have characterized a primary CD4-independent HIV-1 isolate (92UG046-T8) with a truncated cytoplasmic tail that was able to infect and induce syncytia in primary lymphocytes from human, chimpanzee, and monkey, as well as CD4-negative cell lines from human and monkey. Increased syncytia were also noticeable with 293 cells expressing the cloned envelope from the 92UG046-T8 isolate suggesting envelope-mediated cellular fusion. Except pooled serum from HIV-1-infected individuals, monoclonal anti-envelope antibodies or antibodies/antagonists against CD4, CXCR4, and CCR5 were not able to prevent infection by the 92UG046-T8 isolate. This is the first report showing a primary HIV-1 variant with truncated cytoplasmic tail which is highly fusogenic and can infect a broad range of cells from human and non-human origins. In vivo evolution of similar HIV-1 mutants may have important implications in AIDS pathogenesis

  9. Patterns in nuclear and mitochondrial DNA reveal historical and recent isolation in the black-tailed godwit (Limosa limosa)

    NARCIS (Netherlands)

    Trimbos, Krijn B.; Doorenweerd, Camiel; Kraaijeveld, Ken; Musters, C.J.M.; Groen, Niko M.; Knijff, Peter de; Piersma, Theunis; de Snoo, Geert R.

    2014-01-01

    On the basis of morphological differences, three subspecies of Black-tailed Godwit (Limosa limosa) have been recognized (L. l. limosa, L. l. islandica and L. l. melanuroides). In previous studies mitochondrial DNA (mtDNA) sequence data showed minimal genetic divergence between the three subspecies

  10. Patterns in Nuclear and Mitochondrial DNA Reveal Historical and Recent Isolation in the Black-Tailed Godwit (Limosa limosa)

    NARCIS (Netherlands)

    Trimbos, K.B.; Doorenweerd, C.; Kraaijeveld, K.; Musters, C.J.M.; Groen, N.M.; Kniff, de P.; Piersma, T.; Snoo, de G.R.

    2014-01-01

    On the basis of morphological differences, three subspecies of Black-tailed Godwit (Limosa limosa) have been recognized (L. l. limosa, L. l. islandica and L. l. melanuroides). In previous studies mitochondrial DNA (mtDNA) sequence data showed minimal genetic divergence between the three subspecies

  11. Patterns in Nuclear and Mitochondrial DNA Reveal Historical and Recent Isolation in the Black-Tailed Godwit (

    NARCIS (Netherlands)

    Trimbos, K.B.; Doorenweerd, C.; Kraaijeveld, K.; Musters, C.J.M.; Groen, N.M.; de Knijff, P.; Piersma, T.; de Snoo, G.R.

    2014-01-01

    On the basis of morphological differences, three subspecies of Black-tailed Godwit (Limosa limosa) have been recognized (L. l. limosa, L. l. islandica and L. l. melanuroides). In previous studies mitochondrial DNA (mtDNA) sequence data showed minimal genetic divergence between the three subspecies

  12. Genome sequence of the acid-tolerant Desulfovibrio sp. DV isolated from the sediments of a Pb-Zn mine tailings dam in the Chita region, Russia

    Directory of Open Access Journals (Sweden)

    Anastasiia Kovaliova

    2017-03-01

    Full Text Available Here we report the draft genome sequence of the acid-tolerant Desulfovibrio sp. DV isolated from the sediments of a Pb-Zn mine tailings dam in the Chita region, Russia. The draft genome has a size of 4.9 Mb and encodes multiple K+-transporters and proton-consuming decarboxylases. The phylogenetic analysis based on concatenated ribosomal proteins revealed that strain DV clusters together with the acid-tolerant Desulfovibrio sp. TomC and Desulfovibrio magneticus. The draft genome sequence and annotation have been deposited at GenBank under the accession number MLBG00000000.

  13. Improvement of the Uranium Sequestration Ability of a Chlamydomonas sp. (ChlSP Strain) Isolated From Extreme Uranium Mine Tailings Through Selection for Potential Bioremediation Application.

    Science.gov (United States)

    Baselga-Cervera, Beatriz; Romero-López, Julia; García-Balboa, Camino; Costas, Eduardo; López-Rodas, Victoria

    2018-01-01

    The extraction and processing of uranium (U) have polluted large areas worldwide, rendering anthropogenic extreme environments inhospitable to most species. Noticeably, these sites are of great interest for taxonomical and applied bioprospection of extremotolerant species successfully adapted to U tailings contamination. As an example, in this work we have studied a microalgae species that inhabits extreme U tailings ponds at the Saelices mining site (Salamanca, Spain), characterized as acidic (pH between 3 and 4), radioactive (around 4 μSv h -1 ) and contaminated with metals, mainly U (from 25 to 48 mg L -1 ) and zinc (from 17 to 87 mg L -1 ). After isolation of the extremotolerant ChlSP strain, morphological characterization and internal transcribed spacer (ITS)-5.8S gene sequences placed it in the Chlamydomonadaceae , but BLAST analyses identity values, against the nucleotide datasets at the NCBI database, were very low (tailings waters based on newly evolved extremotolerants and outline the potential of artificial selection in the improvement of desired features in microalgae by experimental adaptation and selection.

  14. Improvement of the Uranium Sequestration Ability of a Chlamydomonas sp. (ChlSP Strain) Isolated From Extreme Uranium Mine Tailings Through Selection for Potential Bioremediation Application

    Science.gov (United States)

    Baselga-Cervera, Beatriz; Romero-López, Julia; García-Balboa, Camino; Costas, Eduardo; López-Rodas, Victoria

    2018-01-01

    The extraction and processing of uranium (U) have polluted large areas worldwide, rendering anthropogenic extreme environments inhospitable to most species. Noticeably, these sites are of great interest for taxonomical and applied bioprospection of extremotolerant species successfully adapted to U tailings contamination. As an example, in this work we have studied a microalgae species that inhabits extreme U tailings ponds at the Saelices mining site (Salamanca, Spain), characterized as acidic (pH between 3 and 4), radioactive (around 4 μSv h−1) and contaminated with metals, mainly U (from 25 to 48 mg L−1) and zinc (from 17 to 87 mg L−1). After isolation of the extremotolerant ChlSP strain, morphological characterization and internal transcribed spacer (ITS)-5.8S gene sequences placed it in the Chlamydomonadaceae, but BLAST analyses identity values, against the nucleotide datasets at the NCBI database, were very low (microalgae growth curve; ChlSG cells removed close to 4 mg L−1 of U in 24 days. These findings open up promising prospects for sustainable management of U tailings waters based on newly evolved extremotolerants and outline the potential of artificial selection in the improvement of desired features in microalgae by experimental adaptation and selection. PMID:29662476

  15. Head flexion angle while using a smartphone.

    Science.gov (United States)

    Lee, Sojeong; Kang, Hwayeong; Shin, Gwanseob

    2015-01-01

    Repetitive or prolonged head flexion posture while using a smartphone is known as one of risk factors for pain symptoms in the neck. To quantitatively assess the amount and range of head flexion of smartphone users, head forward flexion angle was measured from 18 participants when they were conducing three common smartphone tasks (text messaging, web browsing, video watching) while sitting and standing in a laboratory setting. It was found that participants maintained head flexion of 33-45° (50th percentile angle) from vertical when using the smartphone. The head flexion angle was significantly larger (p smartphone, could be a main contributing factor to the occurrence of neck pain of heavy smartphone users. Practitioner Summary: In this laboratory study, the severity of head flexion of smartphone users was quantitatively evaluated when conducting text messaging, web browsing and video watching while sitting and standing. Study results indicate that text messaging while sitting caused the largest head flexion than that of other task conditions.

  16. Tellurite-, tellurate-, and selenite-based anaerobic respiration by strain CM-3 isolated from gold mine tailings.

    Science.gov (United States)

    Maltman, Chris; Piercey-Normore, Michele D; Yurkov, Vladimir

    2015-09-01

    The newly discovered strain CM-3, a Gram-negative, rod-shaped bacterium from gold mine tailings of the Central Mine in Nopiming Provincial Park, Canada, is capable of dissimilatory anaerobic reduction of tellurite, tellurate, and selenite. CM-3 possesses very high level resistance to these oxides, both aerobically and anaerobically. During aerobic growth, tellurite and tellurate resistance was up to 1500 and 1000 µg/ml, respectively. In the presence of selenite, growth occurred at the highest concentration tested, 7000 µg/ml. Under anaerobic conditions, resistance was decreased to 800 µg/ml for the Te oxides; however, much like under aerobic conditions, growth with selenite still took place at 7000 µg/ml. In the absence of oxygen, CM-3 couples oxide reduction to an increase in biomass. Following an initial drop in viable cells, due to switching from aerobic to anaerobic conditions, there was an increase in CFU/ml greater than one order of magnitude in the presence of tellurite (6.6 × 10(3)-8.6 × 10(4) CFU/ml), tellurate (4.6 × 10(3)-1.4 × 10(5) CFU/ml), and selenite (2.7 × 10(5)-5.6 × 10(6) CFU/ml). A control culture without metalloid oxides showed a steady decrease in CFU/ml with no recovery. ATP production was also increased in the presence of each oxide, further indicating anaerobic respiration. Partial 16S rRNA gene sequencing revealed a 99.0 % similarity of CM-3 to Pseudomonas reactans.

  17. Phylogeographic structure in long-tailed voles (Rodentia: Arvicolinae) belies the complex Pleistocene history of isolation, divergence, and recolonization of Northwest North America's fauna.

    Science.gov (United States)

    Sawyer, Yadéeh E; Cook, Joseph A

    2016-09-01

    Quaternary climate fluctuations restructured biodiversity across North American high latitudes through repeated episodes of range contraction, population isolation and divergence, and subsequent expansion. Identifying how species responded to changing environmental conditions not only allows us to explore the mode and tempo of evolution in northern taxa, but also provides a basis for forecasting future biotic response across the highly variable topography of western North America. Using a multilocus approach under a Bayesian coalescent framework, we investigated the phylogeography of a wide-ranging mammal, the long-tailed vole, Microtus longicaudus . We focused on populations along the North Pacific Coast to refine our understanding of diversification by exploring the potentially compounding roles of multiple glacial refugia and more recent fragmentation of an extensive coastal archipelago. Through a combination of genetic data and species distribution models (SDMs), we found that historical climate variability influenced contemporary genetic structure, with multiple isolated locations of persistence (refugia) producing multiple divergent lineages (Beringian or northern, southeast Alaska or coastal, and southern or continental) during glacial advances. These vole lineages all occur along the North Pacific Coast where the confluence of numerous independent lineages in other species has produced overlapping zones of secondary contact, collectively a suture zone. Finally, we detected high levels of neoendemism due to complex island geography that developed in the last 10,000 years with the rising sea levels of the Holocene.

  18. Genomic insights into a new acidophilic, copper-resistant Desulfosporosinus isolate from the oxidized tailings area of an abandoned gold mine.

    Science.gov (United States)

    Mardanov, Andrey V; Panova, Inna A; Beletsky, Alexey V; Avakyan, Marat R; Kadnikov, Vitaly V; Antsiferov, Dmitry V; Banks, David; Frank, Yulia A; Pimenov, Nikolay V; Ravin, Nikolai V; Karnachuk, Olga V

    2016-08-01

    Microbial sulfate reduction in acid mine drainage is still considered to be confined to anoxic conditions, although several reports have shown that sulfate-reducing bacteria occur under microaerophilic or aerobic conditions. We have measured sulfate reduction rates of up to 60 nmol S cm(-3) day(-1) in oxidized layers of gold mine tailings in Kuzbass (SW Siberia). A novel, acidophilic, copper-tolerant Desulfosporosinus sp. I2 was isolated from the same sample and its genome was sequenced. The genomic analysis and physiological data indicate the involvement of transporters and additional mechanisms to tolerate metals, such as sequestration by polyphosphates. Desulfosporinus sp. I2 encodes systems for a metabolically versatile life style. The genome possessed a complete Embden-Meyerhof pathway for glycolysis and gluconeogenesis. Complete oxidation of organic substrates could be enabled by the complete TCA cycle. Genomic analysis found all major components of the electron transfer chain necessary for energy generation via oxidative phosphorylation. Autotrophic CO2 fixation could be performed through the Wood-Ljungdahl pathway. Multiple oxygen detoxification systems were identified in the genome. Taking into account the metabolic activity and genomic analysis, the traits of the novel isolate broaden our understanding of active sulfate reduction and associated metabolism beyond strictly anaerobic niches. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  19. Biotransformation of As (III to As (V and their stabilization in soil with Bacillus sp. XS2 isolated from gold mine tailing of Xinjiang, China

    Directory of Open Access Journals (Sweden)

    Santosh Kumar Karn

    2016-09-01

    Full Text Available Xinjiang province is one of the most polluted region in China, this region affected by multi-metal problem, especially arsenic (As affect very badly. Two major forms of As present in the environment As (III and As (V as compared to As (V, As (III is much more toxic. Our aim is to remediate As (III contaminated soil by using As (III resistant microbe, having the high transforming ability for As (III to As (V. An As (III oxidizing bacterium Bacillus sp. XS2, isolated and selected from gold mine tailing which have shown high resistance up to 6400 mg L−1 and efficiently transformed up to 4000 mg L−1 in sucrose low phosphate medium (SLP, higher than any of the previous reported Bacillus sp.. In soil, we found that XS2 successfully transformed up to 81% of soluble exchangeable fraction within 10 d in contaminated soil (with 500 mg kg−1, which makes it potential microbe for the removal of contaminated site with arsenic in the environment. Further XS2 was characterized for their molecular basis of resistance and we establish that XS2 having arsenic oxidase enzyme activity which is accountable for the detoxification of arsenic at high concentration and provide resistance to the bacterium. Gene encoding arsenic oxidase (aioA-gene was also amplified from this bacterium using polymerase chain reaction (PCR with degenerate primer. The aioA-gene is specific for the arsenite-oxidizing bacteria. The deduced amino acid sequence had shown 42% similarity with pseudomonas sp. arsenic oxidase. Further, the strain was characterized by 16s rRNA gene sequence analysis and shown maximum similarity with Bacillus sp.

  20. Measuring Gravitational Flexion in ACS Clusters

    Science.gov (United States)

    Goldberg, David

    2005-07-01

    We propose measurement of the gravitational "Flexion" signal in ACS cluster images. The flexion, or "arciness" of a lensed background galaxy arises from variations in the lensing field. As a result, it is extremely sensitive to small scale perturbations in the field, and thus, to substructure in clusters. Moreover, because flexion represents gravitationally induced asymmetries in the lensed image, it is completely separable from traditional measurements of shear, which focus on the induced ellipticity of the image, and thus, the two signals may be extracted simultaneously. Since typical galaxies are roughly symmetric upon 180 degree rotation, even a small induced flexion can potentially produce a noticeable effect {Goldberg & Bacon, 2005}. We propose the measurement of substructure within approximately 4 clusters with high-quality ACS data, and will further apply a test of a new tomographic technique whereby comparisons of lensed arcs at different redshifts may be used to estimate the background cosmology, and thus place constraints on the equation of state of dark energy.

  1. Improving Pre-Operative Flexion in Primary TKA: A Surgical Technique Emphasizing Knee Flexion with 5-Year Follow-Up

    Directory of Open Access Journals (Sweden)

    Edward McPherson

    2014-06-01

    Full Text Available This study prospectively reviews a consecutive series of 228 primary total knee arthroplasty (TKA procedures utilizing a technique to optimize knee flexion. The main features include: (1the use of a “patellar friendly” femoral component and reduced thickness patellar components, (2 patient individualized adjustment of the femoral component rotation set strictly to the anterior-posterior femoral axis, (3a rigorous flexion compartment debridement to remove non-essential posterior femoral bone with a Z-osteotome, and (4incorporation of a rapid recovery protocol with features to promote knee flexion. Results were categorized into three groups: low pre-op flexion (90 degrees and below, regular pre-op flexion (91-125 degrees, and high pre-op flexion (126 degrees and above. Average flexion in the low flexion group improved by 20 degrees at 6 weeks, 28 degrees at 3 months, 31 degrees at 1 year, and 30 degrees at 5 years. In the regular flexion group, average flexion improved by 2 degrees at 6 weeks, 10 degrees at 3 months, 12 degrees at 1 year, and 13 degrees at 5 years. Finally, in the high flexion group, average flexion decreased by 7 degrees at 6 weeks, regained preoperative levels at 3 months, and increased by 3 degrees at 1 year and 4 degrees at 5 years. In summary, a technique that emphasizes patellofemoral kinematics can consistently improve flexion in TKA in short and long-term follow-up.

  2. Epidemiology of toxoplasmosis in white tailed deer (Odocoileus virginianus): occurrence, congenital transmission, correlates of infection, isolation, and genetic characterization of Toxoplasma gondii

    Science.gov (United States)

    The prevalence of Toxoplasma gondii in white tailed deer (WTD) in the USA is high, but little is known of the epidemiology of toxoplasmosis in this host. In the present study, we compared T. gondii seroprevalence from 531 WTD collected in 2012 and 2013 from a Metropolitan Park in Ohio, and and 485 W...

  3. Isolation and characterization of Burkholderia fungorum Gan-35 with the outstanding ammonia nitrogen-degrading ability from the tailings of rare-earth-element mines in southern Jiangxi, China.

    Science.gov (United States)

    Feng, Ai-Juan; Xiao, Xi; Ye, Cong-Cong; Xu, Xiao-Ming; Zhu, Qing; Yuan, Jian-Ping; Hong, Yue-Hui; Wang, Jiang-Hai

    2017-12-01

    The exploitation of rare-earth-element (REE) mines has resulted in severe ammonia nitrogen pollution and induced hazards to environments and human health. Screening microorganisms with the ammonia nitrogen-degrading ability provides a basis for bioremediation of ammonia nitrogen-polluted environments. In this study, a bacterium with the outstanding ammonia nitrogen-degrading capability was isolated from the tailings of REE mines in southern Jiangxi Province, China. This strain was identified as Burkholderia fungorum Gan-35 according to phenotypic and phylogenetic analyses. The optimal conditions for ammonia-nitrogen degradation by strain Gan-35 were determined as follows: pH value, 7.5; inoculum dose, 10%; incubation time, 44 h; temperature, 30 °C; and C/N ratio, 15:1. Strain Gan-35 degraded 68.6% of ammonia nitrogen under the optimized conditions. Nepeta cataria grew obviously better in the ammonia nitrogen-polluted soil with strain Gan-35 than that without inoculation, and the decrease in ammonia-nitrogen contents of the former was also more obvious than the latter. Besides, strain Gan-35 exhibited the tolerance to high salinities. In summary, strain Gan-35 harbors the ability of both ammonia-nitrogen degradation at high concentrations and promoting plant growth. This work has reported a Burkholderia strain with the ammonia nitrogen-degrading capability for the first time and is also the first study on the isolation of a bacterium with the ammonia nitrogen-degrading ability from the tailings of REE mines. The results are useful for developing an effective method for microbial remediation of the ammonia nitrogen-polluted tailings of REE mines.

  4. Tail gut cyst.

    Science.gov (United States)

    Rao, G Mallikarjuna; Haricharan, P; Ramanujacharyulu, S; Reddy, K Lakshmi

    2002-01-01

    The tail gut is a blind extension of the hindgut into the tail fold just distal to the cloacal membrane. Remnants of this structure may form tail gut cyst. We report a 14-year-old girl with tail gut cyst that presented as acute abdomen. The patient recovered after cyst excision.

  5. In vivo metacarpophalanageal joint collateral ligament length changes during flexion.

    Science.gov (United States)

    Sun, Y C; Sheng, X M; Chen, J; Qian, Z W

    2017-07-01

    We investigated the in vivo length changes of the collateral ligaments of metacarpophalangeal joint during flexion. We obtained computed tomography scans of index, middle, ring and little fingers at 0°, 30°, 60° and 90° of joint flexion from six hands of six healthy adult volunteers. Three of them had their dominant right hand studied, and the other three had their non-dominant left hand studied. We measured and analysed the radial and ulnar collateral ligaments of each metacarpophalangeal joint from the reconstructed images. We found that the dorsal and middle portions of the both radial and ulnar collateral ligament lengthened progressively during digital flexion and reached the maximum at 90° flexion. The length of the volar portion increased from 0° to 30° flexion and then decreased from 30° to 60° flexion, reaching the minimum at 90°. In conclusion, three portions of collateral ligaments on both sides of the metacarpophalangeal joint have variable length changes during flexion, which act to stabilize the joint through its flexion arc.

  6. Do patients care about higher flexion in total knee arthroplasty?

    DEFF Research Database (Denmark)

    Thomsen, Morten G; Husted, Henrik; Otte, Kristian Stahl

    2013-01-01

    BACKGROUND: Little information exists to support that patients care about flexion beyond what is needed to perform activities of daily living (ADL) after Total knee arthroplasty (TKA). The purpose of this study was to investigate if the achievement of a higher degree of knee flexion after TKA would...

  7. Clinical outcome of increased flexion gap after total knee arthroplasty. Can controlled gap imbalance improve knee flexion?

    Science.gov (United States)

    Ismailidis, P; Kuster, M S; Jost, B; Giesinger, K; Behrend, H

    2017-06-01

    Increased range of motion (ROM) while maintaining joint stability is the goal of modern total knee arthroplasty (TKA). A biomechanical study has shown that small increases in flexion gap result in decreased tibiofemoral force beyond 90° flexion. The purpose of this paper was to investigate clinical implications of controlled increased flexion gap. Four hundred and four TKAs were allocated into one of two groups and analysed retrospectively. In the first group (n = 352), flexion gap exceeded extension gap by 2.5 mm, while in the second group (n = 52) flexion gap was equal to the extension gap. The procedures were performed from 2008 to 2012. The patients were reviewed 12 months postoperatively. Objective clinical results were assessed for ROM, mediolateral and sagittal stability. Patient-reported outcome measures were the WOMAC score and the Forgotten Joint Score (FJS-12). After categorizing postoperative flexion into three groups (poor < 90°, satisfactory 91°-119°, good ≥ 120°) significantly more patients in group 1 achieved satisfactory or good ROM (p = 0.006). Group 1 also showed a significantly higher mean FJS-12 (group 1: 73, group 2: 61, p = 0.02). The mean WOMAC score was 11 in the first and 14 in the second group (n.s.). Increase in flexion gap did not influence knee stability. The clinical relevance of this study is that a controlled flexion gap increase of 2.5 mm may have a positive effect on postoperative flexion and patient satisfaction after TKA. Neither knee stability in the coronal and sagittal planes nor complications were influenced by a controlled increase in flexion gap. III.

  8. Ecological aspects of microorganisms inhabiting uranium mill tailings

    Science.gov (United States)

    Miller, C.L.; Landa, E.R.; Updegraff, D.M.

    1987-01-01

    Numbers and types of microorganisms in uranium mill tailings were determined using culturing techniques. Arthrobacter were found to be the predominant microorganism inhabiting the sandy tailings, whereas Bacillus and fungi predominated in the slime tailings. Sulfate-reducing bacteria, capable of leaching radium, were isolated in low numbers from tailings samples but were isolated in significantly high numbers from topsoil in contact with the tailings. The results are placed in the context of the magnitude of uranium mill tailings in the United States, the hazards posed by the tailings, and how such hazards could be enhanced or diminished by microbial activities. Patterns in the composition of the microbial population are evaluated with respect to the ecological variables that influence microbial growth. ?? 1987 Springer-Verlag New York Inc.

  9. Femoral neck radiography: effect of flexion on visualization

    International Nuclear Information System (INIS)

    Garry, S.C.; Jhangri, G.S.; Lambert, R.G.W.

    2005-01-01

    To determine whether flexion improves radiographic visualization of the femoral neck when the femur is externally rotated. Five human femora, with varying neck-shaft and anteversion angles, were measured and immobilized. Degree of flexion required to bring the femoral neck horizontal was measured, varying the rotation. Next, one bone was radiographed in 16 positions, varying rotation in 15 o and flexion in 10 o increments. Radiographs were presented in randomized blinded fashion to 15 staff radiologists for scoring of femoral neck visualization. Following this, all 5 bones were radiographed in 4 positions of rotation and at 0 o and 20 o flexion, and blinded randomized review of radiographs was repeated. Comparisons between angles and rotations were made using the Mann-Whitney test. The flexion angle required to bring the long axis of the femoral neck horizontal correlated directly with the degree of external rotation (ρ o internal rotation to 30 o external rotation (ρ o flexion was applied to bones in external rotation, visualization significantly improved at 15 o (ρ o (ρ o ) of flexion can significantly improve radiographic visualization. This manoeuvre could be useful for radiography of the femoral neck when initial radiographs are inadequate because of external rotation of the leg. (author)

  10. Uranium Mill Tailings Management

    International Nuclear Information System (INIS)

    Nelson, J.D.

    1982-01-01

    This book presents the papers given at the Fifth Symposium on Uranium Mill Tailings Management. Advances made with regard to uranium mill tailings management, environmental effects, regulations, and reclamation are reviewed. Topics considered include tailings management and design (e.g., the Uranium Mill Tailings Remedial Action Project, environmental standards for uranium mill tailings disposal), surface stabilization (e.g., the long-term stability of tailings, long-term rock durability), radiological aspects (e.g. the radioactive composition of airborne particulates), contaminant migration (e.g., chemical transport beneath a uranium mill tailings pile, the interaction of acidic leachate with soils), radon control and covers (e.g., radon emanation characteristics, designing surface covers for inactive uranium mill tailings), and seepage and liners (e.g., hydrologic observations, liner requirements)

  11. ISOLATION AND CHARACTERISTIC OF NITROGEN-FIXING BACTERIA AND PHOSPHATE-SOLUBILIZING BACTERIA FROM SOIL HIGH IN MERCURY IN TAILINGS AND COMPOST AREAS OF ARTISANAL GOLD MINE

    Directory of Open Access Journals (Sweden)

    Yulia Nuraini

    2015-02-01

    Full Text Available The research was conducted at Brawijaya University and West Nusa Tenggara, from March 2013 to October 2013. The tailings areas of the gold mine contains high mercury (Hg as much as 1,090 ppm, and living microbes (resistance exist in a small number in such a condition. Microbial P solvents encountered came from the genus Bacillus with a population of 23 x 103 cfu g-1 and N-fixing bacteria encountered are of the genus Bacillus, with a population of 4 x 103 cfu g-1. Identification of species using Becton Dickinson Phoenix test, both species belong to Bacillus megaterium and Bacillus pumilus. While the waste corn and peanuts that has been composted for 4 weeks acquired P-solubilizing bacteria, such as Enterobacter, Bacillus and Pseudomonas, and N-fixing bacteria found was Pseudomonas and Azotobacter. While testing the activity and antagonism of N-fixing and P-solubilizing bacteria, the result on agar media did not show antagonism in its growth. Bacillus pumilus and Bacillus megaterium effective at 5 % molasses medium with the number of 0.15 x 1012 on seven days of incubation.

  12. Heavy tails of OLS

    DEFF Research Database (Denmark)

    Mikosch, Thomas Valentin; de Vries, Casper

    2013-01-01

    Suppose the tails of the noise distribution in a regression exhibit power law behavior. Then the distribution of the OLS regression estimator inherits this tail behavior. This is relevant for regressions involving financial data. We derive explicit finite sample expressions for the tail probabili...

  13. Are the Outcomes of Revision Knee Arthroplasty for Flexion Instability the Same as for Other Major Failure Mechanisms?

    Science.gov (United States)

    Rajgopal, Ashok; Panjwani, Taufiq R; Rao, Arun; Dahiya, Vivek

    2017-10-01

    Aseptic loosening, infection, and flexion instability have emerged as the leading etiologies for revision after total knee arthroplasty (TKA). Although studies have reported improved outcomes after revision TKA, the relative functional and clinical outcomes of patients revised for flexion instability and other failure etiologies have not been extensively reported. The aim of the study was to compare the functional and patient-reported outcomes of revision TKA for the common failure etiologies. We retrospectively reviewed records of 228 consecutive cases of revision TKA from 2008 to 2014. Revisions performed for aseptic loosening (n = 53), septic revisions (n = 48), and isolated flexion instability (n = 45) with a minimum of 18 months follow-up were included for analysis. Revision for all other etiologies (n = 82) were excluded. The Modified Knee Society Score (KSS), KSS Function, and Western Ontario and McMaster Universities Osteoarthritis Index were recorded for all cases. A 7-point Likert scale was used to record patient's perception of outcomes after revision surgery and analyzed based on etiology. Although all groups showed improvement in outcome after revision TKA, the changes in Modified KSS and KSS-Function varied according to the etiology of failure of the primary procedure with the smallest improvement being reported by the flexion instability group. Patients undergoing revision for isolated flexion instability have less improvement in functional outcome as compared with other etiologies. We hypothesize this is due to a higher baseline preoperative knee function in the flexion instability group. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Yellow tails in the Red Sea: phylogeography of the Indo-Pacific goatfish Mulloidichthys flavolineatus reveals isolation in peripheral provinces and cryptic evolutionary lineages

    KAUST Repository

    Fernandez-Silva, Iria; Randall, John E.; Coleman, Richard R.; DiBattista, Joseph; Rocha, Luiz A.; Reimer, James D.; Meyer, Carl G.; Bowen, Brian W.

    2015-01-01

    Aim: Broadly distributed reef fishes tend to have high gene flow mediated by a pelagic larval phase. Here, we survey a reef-associated fish distributed across half the tropical oceans, from the Red Sea to the central Pacific. Our goal is to determine whether genetic structure of the broadly distributed Yellowstripe Goatfish (Mulloidichthys flavolineatus) is defined by biogeographical barriers, or facilitated via larval dispersal. Location: Red Sea, Indian Ocean, Pacific Ocean Methods: Specimens were obtained at 19 locations from the Red Sea to Hawai'i. Genetic data include mtDNA cytochrome b (n = 217) and 12 microsatellite loci (n = 185). Analysis of molecular variance (AMOVA), structure, a parsimony network and coalescence analyses were used to resolve recent population history and connectivity. Results: Population structure was significant (mtDNA ϕST = 0.68, P < 0.001; microsatellite FST = 0.08, P < 0.001), but mostly driven by samples from the North-western (NW) Indian Ocean (including the Red Sea) and Hawai'i. There was little population structure across the Indian Ocean to the central Pacific. Hawai'i was distinguished as an isolated population (mtDNA ϕST = 0.03-0.08, P = n.s.; microsatellites FST = 0.05-0.10, P < 0.001). Specimens from the NW Indian Ocean clustered as a distinct phylogenetic lineage that diverged approximately 493 ka (d = 1.7%), which indicates that these fish persisted in isolation through several Pleistocene glacial cycles. Main conclusions: These data reinforce the emerging themes that: (1) phylogeographical breaks within species often coincide with biogeographical breaks based on species distributions, and (2) populations on the periphery of the range (NW Indian Ocean and Hawai'i) are isolated and may be evolutionary incubators producing new species. © 2015 John Wiley & Sons Ltd.

  15. Yellow tails in the Red Sea: phylogeography of the Indo-Pacific goatfish Mulloidichthys flavolineatus reveals isolation in peripheral provinces and cryptic evolutionary lineages

    KAUST Repository

    Fernandez-Silva, Iria

    2015-10-20

    Aim: Broadly distributed reef fishes tend to have high gene flow mediated by a pelagic larval phase. Here, we survey a reef-associated fish distributed across half the tropical oceans, from the Red Sea to the central Pacific. Our goal is to determine whether genetic structure of the broadly distributed Yellowstripe Goatfish (Mulloidichthys flavolineatus) is defined by biogeographical barriers, or facilitated via larval dispersal. Location: Red Sea, Indian Ocean, Pacific Ocean Methods: Specimens were obtained at 19 locations from the Red Sea to Hawai\\'i. Genetic data include mtDNA cytochrome b (n = 217) and 12 microsatellite loci (n = 185). Analysis of molecular variance (AMOVA), structure, a parsimony network and coalescence analyses were used to resolve recent population history and connectivity. Results: Population structure was significant (mtDNA ϕST = 0.68, P < 0.001; microsatellite FST = 0.08, P < 0.001), but mostly driven by samples from the North-western (NW) Indian Ocean (including the Red Sea) and Hawai\\'i. There was little population structure across the Indian Ocean to the central Pacific. Hawai\\'i was distinguished as an isolated population (mtDNA ϕST = 0.03-0.08, P = n.s.; microsatellites FST = 0.05-0.10, P < 0.001). Specimens from the NW Indian Ocean clustered as a distinct phylogenetic lineage that diverged approximately 493 ka (d = 1.7%), which indicates that these fish persisted in isolation through several Pleistocene glacial cycles. Main conclusions: These data reinforce the emerging themes that: (1) phylogeographical breaks within species often coincide with biogeographical breaks based on species distributions, and (2) populations on the periphery of the range (NW Indian Ocean and Hawai\\'i) are isolated and may be evolutionary incubators producing new species. © 2015 John Wiley & Sons Ltd.

  16. Micromechanics of the human vertebral body for forward flexion.

    Science.gov (United States)

    Yang, Haisheng; Nawathe, Shashank; Fields, Aaron J; Keaveny, Tony M

    2012-08-09

    To provide mechanistic insight into the etiology of osteoporotic wedge fractures, we investigated the spatial distribution of tissue at the highest risk of initial failure within the human vertebral body for both forward flexion and uniform compression loading conditions. Micro-CT-based linear elastic finite element analysis was used to virtually load 22 human T9 vertebral bodies in either 5° of forward flexion or uniform compression; we also ran analyses replacing the simulated compliant disc (E=8 MPa) with stiff polymethylmethacrylate (PMMA, E=2500 MPa). As expected, we found that, compared to uniform compression, forward flexion increased the overall endplate axial load on the anterior half of the vertebra and shifted the spatial distribution of high-risk tissue within the vertebra towards the anterior aspect of the vertebral body. However, despite that shift, the high-risk tissue remained primarily within the central regions of the trabecular bone and endplates, and forward flexion only slightly altered the ratio of cortical-to-trabecular load sharing at the mid-vertebral level (mean±SD for n=22: 41.3±7.4% compression; 44.1±8.2% forward flexion). When the compliant disc was replaced with PMMA, the anterior shift of high-risk tissue was much more severe. We conclude that, for a compliant disc, a moderate degree of forward flexion does not appreciably alter the spatial distribution of stress within the vertebral body. Copyright © 2012 Elsevier Ltd. All rights reserved.

  17. Adult Hip Flexion Contracture due to Neurological Disease: A New Treatment Protocol—Surgical Treatment of Neurological Hip Flexion Contracture

    OpenAIRE

    Nicodemo, Alberto; Arrigoni, Chiara; Bersano, Andrea; Massè, Alessandro

    2014-01-01

    Congenital, traumatic, or extrinsic causes can lead people to paraplegia; some of these are potentially; reversible and others are not. Paraplegia can couse hip flexion contracture and, consequently, pressure sores, scoliosis, and hyperlordosis; lumbar and groin pain are strictly correlated. Scientific literature contains many studies about children hip flexion related to neurological diseases, mainly caused by cerebral palsy; only few papers focus on this complication in adults. In this stu...

  18. Consolidation of tailings

    International Nuclear Information System (INIS)

    Nelson, J.D.; Wardwell, R.E.; Abt, S.R.; Staub, W.P.

    1983-09-01

    The integrity of cover systems placed on tailings impoundments will be affected by the potential for differential settlement of the tailings surface. Settlement of the sand fraction will occur relatively rapidly. The slimes will take longer time for consolidation and will produce greater settlement. This report reviews the phenomenon of consolidation for saturated and unsaturated tailings. The effect of load application by cover placement and the extent to which dewatering of tailings will cause consolidation are considered. In addition, the feasibility of inducing consolidation by alternative means and the potential applicability of these methods to tailings impoundments reclamation are discussed. Differential settlement of the tailings will cause tensile strain to be developed in covers. This strain could be large enough to cause cracking within a relatively brittle compacted clay. Dewatering of tailings by drainage can cause settlement even greater than that by placement of a cover material. Dewatering of the tailings would also increase the stability of the tailings surface, thereby enhancing reclamation operations. Consequently, in view of the enhanced surface stability and the fact that a portion of the differential settlement can be accomplished prior to cover placement, dewatering of tailings impoundments during operations may have benefical effects

  19. Isolation and characterization of polymorphic microsatellite markers in the black spiny tailed iguana (Ctenosaura pectinata) and their cross-utility in other Ctenosaura.

    Science.gov (United States)

    Zarza, Eugenia; Pereyra, Ricardo T; Reynoso, Victor H; Emerson, Brent C

    2009-01-01

    We isolated and characterized 10 polymorphic microsatellite loci from the Mexican black iguana (Ctenosaura pectinata) and assessed levels of polymorphism in sampling sites located in the northern areas of the species' distribution range. Two to 19 alleles per locus and observed heterozygosity ranging from 0.15 to 0.96 were detected. These markers will be useful to describe population genetic structure, the extent of gene flow in contact zones, to study the mating system of the species and to address conservation genetics issues. Additionally, we evaluated the potential utility of these markers for studies of other species within the genus Ctenosaura (i.e. C. hemilopha, C. similis and C. oaxacana). © 2009 The Authors. Journal compilation © 2009 Blackwell Publishing Ltd.

  20. Adaptive Genetic Divergence Despite Significant Isolation-by-Distance in Populations of Taiwan Cow-Tail Fir (Keteleeria davidiana var. formosana).

    Science.gov (United States)

    Shih, Kai-Ming; Chang, Chung-Te; Chung, Jeng-Der; Chiang, Yu-Chung; Hwang, Shih-Ying

    2018-01-01

    Double digest restriction site-associated DNA sequencing (ddRADseq) is a tool for delivering genome-wide single nucleotide polymorphism (SNP) markers for non-model organisms useful in resolving fine-scale population structure and detecting signatures of selection. This study performs population genetic analysis, based on ddRADseq data, of a coniferous species, Keteleeria davidiana var. formosana , disjunctly distributed in northern and southern Taiwan, for investigation of population adaptive divergence in response to environmental heterogeneity. A total of 13,914 SNPs were detected and used to assess genetic diversity, F ST outlier detection, population genetic structure, and individual assignments of five populations (62 individuals) of K. davidiana var. formosana . Principal component analysis (PCA), individual assignments, and the neighbor-joining tree were successful in differentiating individuals between northern and southern populations of K. davidiana var. formosana , but apparent gene flow between the southern DW30 population and northern populations was also revealed. Fifteen of 23 highly differentiated SNPs identified were found to be strongly associated with environmental variables, suggesting isolation-by-environment (IBE). However, multiple matrix regression with randomization analysis revealed strong IBE as well as significant isolation-by-distance. Environmental impacts on divergence were found between populations of the North and South regions and also between the two southern neighboring populations. BLASTN annotation of the sequences flanking outlier SNPs gave significant hits for three of 23 markers that might have biological relevance to mitochondrial homeostasis involved in the survival of locally adapted lineages. Species delimitation between K. davidiana var. formosana and its ancestor, K. davidiana , was also examined (72 individuals). This study has produced highly informative population genomic data for the understanding of population

  1. Adaptive Genetic Divergence Despite Significant Isolation-by-Distance in Populations of Taiwan Cow-Tail Fir (Keteleeria davidiana var. formosana

    Directory of Open Access Journals (Sweden)

    Kai-Ming Shih

    2018-02-01

    Full Text Available Double digest restriction site-associated DNA sequencing (ddRADseq is a tool for delivering genome-wide single nucleotide polymorphism (SNP markers for non-model organisms useful in resolving fine-scale population structure and detecting signatures of selection. This study performs population genetic analysis, based on ddRADseq data, of a coniferous species, Keteleeria davidiana var. formosana, disjunctly distributed in northern and southern Taiwan, for investigation of population adaptive divergence in response to environmental heterogeneity. A total of 13,914 SNPs were detected and used to assess genetic diversity, FST outlier detection, population genetic structure, and individual assignments of five populations (62 individuals of K. davidiana var. formosana. Principal component analysis (PCA, individual assignments, and the neighbor-joining tree were successful in differentiating individuals between northern and southern populations of K. davidiana var. formosana, but apparent gene flow between the southern DW30 population and northern populations was also revealed. Fifteen of 23 highly differentiated SNPs identified were found to be strongly associated with environmental variables, suggesting isolation-by-environment (IBE. However, multiple matrix regression with randomization analysis revealed strong IBE as well as significant isolation-by-distance. Environmental impacts on divergence were found between populations of the North and South regions and also between the two southern neighboring populations. BLASTN annotation of the sequences flanking outlier SNPs gave significant hits for three of 23 markers that might have biological relevance to mitochondrial homeostasis involved in the survival of locally adapted lineages. Species delimitation between K. davidiana var. formosana and its ancestor, K. davidiana, was also examined (72 individuals. This study has produced highly informative population genomic data for the understanding of

  2. Uranium tailings bibliography

    International Nuclear Information System (INIS)

    Holoway, C.F.; Goldsmith, W.A.; Eldridge, V.M.

    1975-12-01

    A bibliography containing 1,212 references is presented with its focus on the general problem of reducing human exposure to the radionuclides contained in the tailings from the milling of uranium ore. The references are divided into seven broad categories: uranium tailings pile (problems and perspectives), standards and philosophy, etiology of radiation effects, internal dosimetry and metabolism, environmental transport, background sources of tailings radionuclides, and large-area decontamination

  3. Uranium tailings sampling manual

    International Nuclear Information System (INIS)

    Feenstra, S.; Reades, D.W.; Cherry, J.A.; Chambers, D.B.; Case, G.G.; Ibbotson, B.G.

    1985-01-01

    The purpose of this manual is to describe the requisite sampling procedures for the application of uniform high-quality standards to detailed geotechnical, hydrogeological, geochemical and air quality measurements at Canadian uranium tailings disposal sites. The selection and implementation of applicable sampling procedures for such measurements at uranium tailings disposal sites are complicated by two primary factors. Firstly, the physical and chemical nature of uranium mine tailings and effluent is considerably different from natural soil materials and natural waters. Consequently, many conventional methods for the collection and analysis of natural soils and waters are not directly applicable to tailings. Secondly, there is a wide range in the physical and chemical nature of uranium tailings. The composition of the ore, the milling process, the nature of tailings depositon, and effluent treatment vary considerably and are highly site-specific. Therefore, the definition and implementation of sampling programs for uranium tailings disposal sites require considerable evaluation, and often innovation, to ensure that appropriate sampling and analysis methods are used which provide the flexibility to take into account site-specific considerations. The following chapters describe the objective and scope of a sampling program, preliminary data collection, and the procedures for sampling of tailings solids, surface water and seepage, tailings pore-water, and wind-blown dust and radon

  4. Uranium mill tailings management

    International Nuclear Information System (INIS)

    1982-01-01

    Facilities for the disposal of uranium mill tailings will invariably be subjected to geomorphological and climatological influences in the long-term. Proceedings of a workshop discuss how the principles of geomorphology can be applied to the siting, design, construction, decommissioning and rehabilitation of disposal facilities in order to provide for long-term containment and stability of tailings. The characteristics of tailings and their behaviour after disposal influence the potential impacts which might occur in the long-term. Proceedings of another workshop examine the technologies for uranium ore processing and tailings conditioning with a view to identifying improvements that could be made in such characteristics

  5. Extrinsic versus intrinsic hand muscle dominance in finger flexion.

    Science.gov (United States)

    Al-Sukaini, A; Singh, H P; Dias, J J

    2016-05-01

    This study aims to identify the patterns of dominance of extrinsic or intrinsic muscles in finger flexion during initiation of finger curl and mid-finger flexion. We recorded 82 hands of healthy individuals (18-74 years) while flexing their fingers and tracked the finger joint angles of the little finger using video motion tracking. A total of 57 hands (69.5%) were classified as extrinsic dominant, where the finger flexion was initiated and maintained at proximal interphalangeal and distal interphalangeal joints. A total of 25 (30.5%) were classified as intrinsic dominant, where the finger flexion was initiated and maintained at the metacarpophalangeal joint. The distribution of age, sex, dominance, handedness and body mass index was similar in the two groups. This knowledge may allow clinicians to develop more efficient rehabilitation regimes, since intrinsic dominant individuals would not initiate extrinsic muscle contraction till later in finger flexion, and might therefore be allowed limited early active motion. For extrinsic dominant individuals, by contrast, initial contraction of extrinsic muscles would place increased stress on the tendon repair site if early motion were permitted. © The Author(s) 2016.

  6. Tales of island tails

    NARCIS (Netherlands)

    Groot, de Alma V.; Oost, Albert P.; Veeneklaas, Roos M.; Lammerts, Evert Jan; Duin, van Willem E.; Wesenbeeck, van Bregje K.

    2016-01-01

    The Frisian islands (Southern North Sea) have extensive island tails, i.e. the entire downdrift side of an island consisting of salt marshes, dunes, beaches and beach plains, and green beaches. Currently, large parts of these tails are ageing and losing dynamics, partly due to human influence.

  7. Bar-tailed

    NARCIS (Netherlands)

    Duijns, S.; Hidayati, N.A.; Piersma, T.

    2013-01-01

    Capsule Across the European wintering range Bar-tailed Godwits Limosa lapponica lapponica selected polychaete worms and especially Ragworms Hediste diversicolor, with differences between areas due to variations in prey availability.Aims To determine the diet of Bar-tailed Godwits across their

  8. Tailings management at Nabarlek

    International Nuclear Information System (INIS)

    Waggitt, P.

    1989-01-01

    As the entire uranium deposit at Nabarlek was mined in 1979, the mine pit was available as a tailing's repository from the time of commencement of ore processing. In the early years Nabarlek's tailings were deposited subaqueously. In 1985 the tailings deposition method was changed to a sub-aerial, or semi-dry, method. Over the subsequent three years there was evidence that the tailings settled further and squeezed water from lower layers. The water was pumped away and treated for removal of radium before being evaporated in one of the mine's evaporation ponds. When milling was completed in 1988 it was decided to try and increase the rate of water removal and so obtain even greater consolidation of the trailings in a shorter time. This was achieved by loading the tailings with a layer of screened leached sands and waste rock placed on a layer of geotextile filter fabric that had been laid over the whole of the tailings surface in the pit. Once this was completed a modified piling rig was used to insert vertical drains, or wicks, up to 30 metres into the tailings. The drains were placed on a square grid at a spacing of 3.25 metres. Water that was forced out of the tailings by the downward pressure of the sand and rock could flow freely to the surface up these drains. Once at the surface the water was gathered into a sump and pumped away for treatment as before. The drains are working very well at present although it will be some considerable time before the water stops flowing. Already settlement of the tailings is apparent and the settled density of the material is increasing. As far as is known this is the first time that such a system has been employed on mine tailings in a pit in this way

  9. Frost evolution in tailings

    International Nuclear Information System (INIS)

    1991-04-01

    A review was carried out on the physical and thermal mechanisms of permafrost evaluation in soils and uranium tailings. The primary mechanism controlling permafrost evolution is conductive heat transfer with the latent heat of fusion of water being liberated as phase change occurs. Depending on the soil properties and freezing rate, pore water can be expelled from the frost front or pore water can migrate towards the frost front. Solute redistribution may occur as the frost front penetrates into the soil. The rate of frost penetration is a function of the thermal properties of the tailings and the climatic conditions. Computer modelling programmes capable of modelling permafrost evolution were reviewed. The GEOTHERM programme was selected as being the most appropriate for this study. The GEOTHERM programme uses the finite element method of thermal analysis. The ground surface temperature is determined by solving the energy balance equations a the ground surface. The GEOTHERM programme was used to simulate the permafrost evolution in the Key Lake Mine tailings located in north central Saskatchewan. The analyses indicated that the existing frozen zones in the tailing pond will eventually thaw if an average snow depth covers the tailings. Hundreds of years are required to thaw the tailings. If minimal snow cover is present the extent of the frozen zone in the tailings will increase

  10. Posterolateral Corner Reconstruction using the Anatomical Two-Tailed Graft Technique: Clinical Outcomes in the Multiligament Injured Knee.

    Science.gov (United States)

    Woodmass, Jarret M; Sanders, Thomas L; Johnson, Nick R; Wu, Isabella T; Krych, Aaron J; Stuart, Michael J; Levy, Bruce A

    2018-02-14

    Injury to the posterolateral corner (PLC) of the knee can lead to both varus and rotational instability. Multiple PLC reconstruction techniques have been described, including one-tailed graft (fibula-based constructs) or two-tailed graft (combined fibula- and tibia-based constructs). The purpose of our study was to evaluate the clinical outcomes of anatomical two-tailed graft reconstruction of the PLC in the setting of multiligament knee injuries (MKLIs) with grade III varus instability. Patients were identified through a prospective MLKI database between 2004 and 2013. Patients who received fibular collateral ligament and PLC reconstructions using a two-tailed graft and had a minimum follow-up of 2 years were included. Patients were assessed for clinical laxity grade, range of motion, and functional outcomes using Lysholm and International Knee Documentation Committee (IKDC) scores. Twenty patients (16 male, 4 female) with a mean age of 30.7 (range: 16-52) and a mean follow-up of 52.2 months (range: 24-93 months) were included. Knee dislocation (KD) grades included: 4 KD-1, 10 KD 3-L, 5 KD-4, and 1 KD-5. No patients had isolated PLC injuries. Mean IKDC and Lysholm score were 73.1 ± 25.8 and 78 ± 26, respectively. Mean range of motion was -1.1 to 122.8. In full extension, two patients (10%) had grade 1 laxity to varus stress. In 30 degrees of knee flexion, five (25%) patients had grade 1 laxity, and two (10%) had grade 2 laxity. Anatomical two-tailed PLC reconstruction can reliably restore varus stability when performed on patients with MLKIs and type C posterolateral instability with hyperextension external rotation recurvatum deformity. Satisfactory functional outcome scores were achieved in the majority of patients. This study supports the use of an anatomical two-tailed PLC reconstruction in the multiligament injured knee. The level of evidence is IV, case series. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  11. The Tail of BPM

    Science.gov (United States)

    Kruba, Steve; Meyer, Jim

    Business process management suites (BPMS's) represent one of the fastest growing segments in the software industry as organizations automate their key business processes. As this market matures, it is interesting to compare it to Chris Anderson's 'Long Tail.' Although the 2004 "Long Tail" article in Wired magazine was primarily about the media and entertainment industries, it has since been applied (and perhaps misapplied) to other markets. Analysts describe a "Tail of BPM" market that is, perhaps, several times larger than the traditional BPMS product market. This paper will draw comparisons between the concepts in Anderson's article (and subsequent book) and the BPM solutions market.

  12. Comparison of hyperpronation and supination‑flexion techniques in ...

    African Journals Online (AJOL)

    2013-07-24

    Jul 24, 2013 ... Green DA, Linares YM, Garcia Pena MB, Greenberg M, Baker RL: Randomized comparison of pain perception during radial head subluxation using supination‑ flexion or forced pronation. Pediatr Emerg Care 2006;22:235‑8. 8. McDonald LJ, Whitelaw C, Goldsmith L. Radial head subluxation: Comparing.

  13. The problem of abandoned uranium tailings in northern Saskatchewan

    International Nuclear Information System (INIS)

    Swanson, S.; Abouguendia, Z.

    1981-11-01

    Two Saskatchewan tailings sites, Lorado and Gunnar, covering approximately 89 ha., were abandoned in the early 1960s leaving untreated tailings in lakes and depressions. This report reviews the literature on environmental conditions in abandoned uranium tailings and available managmenet and mitigation options, and identifies research requirements essential for proper treatment of these two sites. The recommended management plan includes isolation of the exposed tailings area from surface waters, stabilization of the exposed tailings surfaces, diversion of runoff around tailings, treatment of overflow water before release, and implementation of an environmental monitoring program. Revegetation appears to be a promising stabilization measure, but research is needed into propagation methods of appropriate native species. Studies of the existing geological and hydrological conditions at both sites, detailed characterization of the wastes, field testing of different surface treatment methods, and nutrient cycling investigations are also needed

  14. Estimation of Jump Tails

    DEFF Research Database (Denmark)

    Bollerslev, Tim; Todorov, Victor

    We propose a new and flexible non-parametric framework for estimating the jump tails of Itô semimartingale processes. The approach is based on a relatively simple-to-implement set of estimating equations associated with the compensator for the jump measure, or its "intensity", that only utilizes...... the weak assumption of regular variation in the jump tails, along with in-fill asymptotic arguments for uniquely identifying the "large" jumps from the data. The estimation allows for very general dynamic dependencies in the jump tails, and does not restrict the continuous part of the process...... and the temporal variation in the stochastic volatility. On implementing the new estimation procedure with actual high-frequency data for the S&P 500 aggregate market portfolio, we find strong evidence for richer and more complex dynamic dependencies in the jump tails than hitherto entertained in the literature....

  15. Tail posture predicts tail damage among weaned piglets

    NARCIS (Netherlands)

    Zonderland, J.J.; Riel, van J.W.; Bracke, M.B.M.; Kemp, B.; Hartog, den L.A.; Spoolder, H.A.M.

    2009-01-01

    Tail biting in pigs is a widespread behavioural vice with significant animal welfare and economic consequences. All too often, tail biting is not diagnosed nor dealt with until tail damage is present. To effectively reduce the negative effects of tail biting, it must be diagnosed in an early stage.

  16. Markov Tail Chains

    OpenAIRE

    janssen, Anja; Segers, Johan

    2013-01-01

    The extremes of a univariate Markov chain with regularly varying stationary marginal distribution and asymptotically linear behavior are known to exhibit a multiplicative random walk structure called the tail chain. In this paper we extend this fact to Markov chains with multivariate regularly varying marginal distributions in Rd. We analyze both the forward and the backward tail process and show that they mutually determine each other through a kind of adjoint relation. In ...

  17. Adult Hip Flexion Contracture due to Neurological Disease: A New Treatment Protocol—Surgical Treatment of Neurological Hip Flexion Contracture

    Directory of Open Access Journals (Sweden)

    Alberto Nicodemo

    2014-01-01

    Full Text Available Congenital, traumatic, or extrinsic causes can lead people to paraplegia; some of these are potentially; reversible and others are not. Paraplegia can couse hip flexion contracture and, consequently, pressure sores, scoliosis, and hyperlordosis; lumbar and groin pain are strictly correlated. Scientific literature contains many studies about children hip flexion related to neurological diseases, mainly caused by cerebral palsy; only few papers focus on this complication in adults. In this study we report our experience on surgical treatment of adult hip flexion contracture due to neurological diseases; we have tried to outline an algorithm to choose the best treatment avoiding useless or too aggressive therapies. We present 5 cases of adult hips flexion due to neurological conditions treated following our algorithm. At 1-year-follow-up all patients had a good clinical outcome in terms of hip range of motion, pain and recovery of walking if possible. In conclusion we think that this algorithm could be a good guideline to treat these complex cases even if we need to treat more patients to confirm this theory. We believe also that postoperation physiotherapy it is useful in hip motility preservation, improvement of muscular function, and walking ability recovery when possible.

  18. Adult Hip Flexion Contracture due to Neurological Disease: A New Treatment Protocol—Surgical Treatment of Neurological Hip Flexion Contracture

    Science.gov (United States)

    Nicodemo, Alberto; Arrigoni, Chiara; Bersano, Andrea; Massè, Alessandro

    2014-01-01

    Congenital, traumatic, or extrinsic causes can lead people to paraplegia; some of these are potentially; reversible and others are not. Paraplegia can couse hip flexion contracture and, consequently, pressure sores, scoliosis, and hyperlordosis; lumbar and groin pain are strictly correlated. Scientific literature contains many studies about children hip flexion related to neurological diseases, mainly caused by cerebral palsy; only few papers focus on this complication in adults. In this study we report our experience on surgical treatment of adult hip flexion contracture due to neurological diseases; we have tried to outline an algorithm to choose the best treatment avoiding useless or too aggressive therapies. We present 5 cases of adult hips flexion due to neurological conditions treated following our algorithm. At 1-year-follow-up all patients had a good clinical outcome in terms of hip range of motion, pain and recovery of walking if possible. In conclusion we think that this algorithm could be a good guideline to treat these complex cases even if we need to treat more patients to confirm this theory. We believe also that postoperation physiotherapy it is useful in hip motility preservation, improvement of muscular function, and walking ability recovery when possible. PMID:24707293

  19. Adult Hip Flexion Contracture due to Neurological Disease: A New Treatment Protocol-Surgical Treatment of Neurological Hip Flexion Contracture.

    Science.gov (United States)

    Nicodemo, Alberto; Arrigoni, Chiara; Bersano, Andrea; Massè, Alessandro

    2014-01-01

    Congenital, traumatic, or extrinsic causes can lead people to paraplegia; some of these are potentially; reversible and others are not. Paraplegia can couse hip flexion contracture and, consequently, pressure sores, scoliosis, and hyperlordosis; lumbar and groin pain are strictly correlated. Scientific literature contains many studies about children hip flexion related to neurological diseases, mainly caused by cerebral palsy; only few papers focus on this complication in adults. In this study we report our experience on surgical treatment of adult hip flexion contracture due to neurological diseases; we have tried to outline an algorithm to choose the best treatment avoiding useless or too aggressive therapies. We present 5 cases of adult hips flexion due to neurological conditions treated following our algorithm. At 1-year-follow-up all patients had a good clinical outcome in terms of hip range of motion, pain and recovery of walking if possible. In conclusion we think that this algorithm could be a good guideline to treat these complex cases even if we need to treat more patients to confirm this theory. We believe also that postoperation physiotherapy it is useful in hip motility preservation, improvement of muscular function, and walking ability recovery when possible.

  20. MR assessment of movement and morphologic change in the menisci during knee flexion

    International Nuclear Information System (INIS)

    Kawahara, Y.; Uetani, M.; Fuchi, K.; Eguchi, H.; Hayashi, K.

    1999-01-01

    To examine movement and morphologic alteration in the menisci during knee flexion. Twenty healthy knees were imaged at 0 degrees, 45 degrees, and 90 degrees of passive non-weight-bearing flexion in the sagittal plane with MR. In each meniscus, posterior movement distance during knee flexion and the ratio of anteroposterior (a.p.) diameter at flexion to that at extension were calculated. Each meniscus moved posteriorly during knee flexion. Movement was greater in the anterior horn than in the posterior horn, and greater in the medial meniscus than in the lateral meniscus (p<0.05). The a.p. diameter of each meniscus was reduced at flexion (p<0.05). Knee flexion normally leads to posterior movement and shortening of the a.p. diameter of the menisci, which may be related to the positioning and curvature of femoral condyles at the femorotibial contact point at knee flexion

  1. MR assessment of movement and morphologic change in the menisci during knee flexion

    International Nuclear Information System (INIS)

    Kawahara, Y.; Uetani, M.; Hayashi, K.; Fuchi, K.; Eguchi, H.

    1999-01-01

    Purpose: To examine movement and morphologic alteration in the menisci during knee flexion. Material and Methods: Twenty healthy knees were imaged at 0 , 45 , and 90 of passive non-weight-bearing flexion in the sagittal plane with MR. In each meniscus, posterior movement distance during knee flexion and the ratio of anteroposterior (a.p.) diameter at flexion to that at extension were calculated. Results: Each meniscus moved posteriorly during knee flexion. Movement was greater in the anterior horn than in the posterior horn, and greater in the medial meniscus than in the lateral meniscus (p<0.05). The a.p. diameter of each meniscus was reduced at flexion (p<0.05). Conclusion: Knee flexion normally leads to posterior movement and shortening of the a.p. diameter of the menisci, which may be related to the positioning and curvature of femoral condyles at the femorotibial contact point at knee flexion. (orig.)

  2. Uranium mill tailings stabilization

    International Nuclear Information System (INIS)

    Hartley, J.N.; Koehmstedt, P.L.; Esterl, D.J.; Freeman, H.D.

    1980-02-01

    Uranium mill tailings pose a potential radiation health hazard to the public. Therefore, stabilization or disposal of these tailings in a safe and environmentally sound way is needed to minimize radon exhalation and other environmental hazards. One of the most promising concepts for stabilizing U tailings is the use of asphalt emulsion to contain radon and other hazardous materials within uranium tailings. This approach is being investigated at the Pacific Northwest Laboratory. Results of these studies indicate that a radon flux reduction of greater than 99% can be obtained using either a poured-on/sprayed-on seal (3.0 to 7.0 mm thick) or an admixture seal (2.5 to 12.7 cm thick) containing about 18 wt % residual asphalt. A field test was carried out in June 1979 at the Grand Junction tailings pile in order to demonstrate the sealing process. A reduction in radon flux ranging from 4.5 to greater than 99% (76% average) was achieved using a 15.2-cm (6-in.) admix seal with a sprayed-on top coat. A hydrostatic stabilizer was used to apply the admix. Following compaction, a spray coat seal was applied over the admix as the final step in construction of a radon seal. Overburden was applied to provide a protective soil layer over the seal. Included in part of the overburden was a herbicide to prevent root penetration

  3. Liquefaction of uranium tailings

    International Nuclear Information System (INIS)

    1992-02-01

    Numerical methods for assessing the liquefaction potential of soils are reviewed with a view to their application to uranium tailings. The method can be divided into two categories: total stress analysis, where changes in pore pressure are not considered in the soil model, and effective stress analysis, where changes in pore pressure are included in the soil model. Effective stress analysis is more realistic, but few computer programs exist for such analysis in two or three dimensions. A simple linearized, two-dimensional, finite element effective stress analysis which incorporates volumetric compaction due to shear motion is described and implemented. The new program is applied to the assessment of liquefaction potential of tailings in the Quirke Mine tailings area near Elliot Lake, Ontario. The results are compared with those of a total stress analysis. Both analyses indicate liquefaction would occur if a magnitude 6.0 earthquake were to occur near the area. However, the extent of liquefaction predicted by the effective stress analysis is much less than that predicted by the total stress analysis. The results of both methods are sensitive to assumed material properties and to the method used to determine the cyclic shear strength of the tailings. Further analysis, incorporating more in situ and/or laboratory data, is recommended before conclusions can be made concerning the dynamic stability of these tailings

  4. Mine tailings disposal

    International Nuclear Information System (INIS)

    Gonzales, P.A.; Adams, B.J.

    1980-06-01

    The hydrologic evaluation of mine tailings disposal sites after they are abandoned is considered in relation to their potential environmental impact on a long term basis. There is a direct relation between the amounts and types of water leaving a disposal site and the severity of the potential damage to the environment. The evaluation of the relative distribution of the precipitation reaching the ground into evaporation, runoff and infiltration is obtained for a selected site and type of tailings material whose characteristics and physical properties were determined in the soils laboratory. A conceptual model of the hydrologic processes involved and the corresponding mathematical model were developed to simulate the physical system. A computer program was written to solve the set of equations forming the mathematical model, considering the physical properties of the tailings and the rainfall data selected. The results indicate that the relative distribution of the precipitation depends on the surface and upper layer of the tailings and that the position of the groundwater table is governed by the flow through the bottom of the profile considered. The slope of the surface of the mass of tailings was found to be one of the principal factors affecting the relative distribution of precipitation and, therefore, the potential pollution of the environment

  5. Analytical shear and flexion of Einasto dark matter haloes

    OpenAIRE

    Retana-Montenegro, E.; Frutos-Alfaro, F.; Baes, M.

    2012-01-01

    N-body simulations predict that dark matter haloes are described by specific density profiles on both galactic- and cluster-sized scales. Weak gravitational lensing through the measurements of their first and second order properties, shear and flexion, is a powerful observational tool for investigating the true shape of these profiles. One of the three-parameter density profiles recently favoured in the description of dark matter haloes is the Einasto profile. We present exact expressions for...

  6. Load and speed effects on the cervical flexion relaxation phenomenon

    Directory of Open Access Journals (Sweden)

    Descarreaux Martin

    2010-03-01

    Full Text Available Abstract Background The flexion relaxation phenomenon (FRP represents a well-studied neuromuscular response that occurs in the lumbar and cervical spine. However, the cervical spine FRP has not been investigated extensively, and the speed of movement and loading effects remains to be characterized. The objectives of the present study were to evaluate the influence of load and speed on cervical FRP electromyographic (EMG and kinematic parameters and to assess the measurement of cervical FRP kinematic and EMG parameter repeatability. Methods Eighteen healthy adults (6 women and 12 men, aged 20 to 39 years, participated in this study. They undertook 2 sessions in which they had to perform a standardized cervical flexion/extension movement in 3 phases: complete cervical flexion; the static period in complete cervical flexion; and extension with return to the initial position. Two different rhythm conditions and 3 different loading conditions were applied to assess load and speed effects. Kinematic and EMG data were collected, and dependent variables included angles corresponding to the onset and cessation of myoelectric silence as well as the root mean square (RMS values of EMG signals. Repeatability was examined in the first session and between the 2 sessions. Results Statistical analyses revealed a significant load effect (P Conclusions The load increase evoked augmented FRP onset and cessation angles as well as heightened muscle activation. Such increments may reflect the need to enhance spinal stability under loading conditions. The kinematic and EMG parameters showed promising repeatability. Further studies are needed to assess kinematic and EMG differences between healthy subjects and patients with neck pain.

  7. Biomechanical analysis of posterior cruciate ligament retaining high-flexion total knee arthroplasty

    NARCIS (Netherlands)

    Zelle, J.; van der Zanden, A.C.; De Waal Malefijt, M.; Verdonschot, Nicolaas Jacobus Joseph

    2009-01-01

    Background High-flexion knee replacements have been developed to accommodate a large range of flexion (>120°) after total knee arthroplasty. Both posterior cruciate ligament retaining and sacrificing high-flexion knee designs have been marketed. The main objective of this study was to evaluate the

  8. Relationship Between Force Production During Isometric Squats and Knee Flexion Angles During Landing.

    Science.gov (United States)

    Fisher, Harry; Stephenson, Mitchell L; Graves, Kyle K; Hinshaw, Taylour J; Smith, Derek T; Zhu, Qin; Wilson, Margaret A; Dai, Boyi

    2016-06-01

    Decreased knee flexion angles during landing are associated with increased anterior cruciate ligament loading. The underlying mechanisms associated with decreased self-selected knee flexion angles during landing are still unclear. The purpose of this study was to establish the relationship between the peak force production at various knee flexion angles (35, 55, 70, and 90°) during isometric squats and the actual knee flexion angles that occur during landing in both men and women. A total of 18 men and 18 women recreational/collegiate athletes performed 4 isometric squats at various knee flexion angles while vertical ground reaction forces were recorded. Participants also performed a jump-landing-jump task while lower extremity kinematics were collected. For women, significant correlations were found between the peak force production at 55 and 70° of knee flexion during isometric squats and the knee flexion angle at initial contact of landing. There were also significant correlations between the peak force production at 55, 70, and 90° of knee flexion during isometric squats and the peak knee flexion angle during landing. These correlations tended to be stronger during isometric squats at greater knee flexion compared with smaller knee flexion. No significant correlations were found for men. Posture-specific strength may play an important role in determining self-selected knee flexion angles during landing for women.

  9. Lumbopelvic flexibility modulates neuromuscular responses during trunk flexion-extension.

    Science.gov (United States)

    Sánchez-Zuriaga, Daniel; Artacho-Pérez, Carla; Biviá-Roig, Gemma

    2016-06-01

    Various stimuli such as the flexibility of lumbopelvic structures influence the neuromuscular responses of the trunk musculature, leading to different load sharing strategies and reflex muscle responses from the afferents of lumbopelvic mechanoreceptors. This link between flexibility and neuromuscular response has been poorly studied. The aim of this study was to investigate the relationship between lumbopelvic flexibility and neuromuscular responses of the erector spinae, hamstring and abdominal muscles during trunk flexion-extension. Lumbopelvic movement patterns were measured in 29 healthy women, who were separated into two groups according to their flexibility during trunk flexion-extension. The electromyographic responses of erector spinae, rectus abdominis and biceps femoris were also recorded. Subjects with greater lumbar flexibility had significantly less pelvic flexibility and vice versa. Subjects with greater pelvic flexibility had a higher rate of relaxation and lower levels of hamstring activation during maximal trunk flexion. The neuromuscular response patterns of the hamstrings seem partially modulated by pelvic flexibility. Not so with the lumbar erector spinae and lumbar flexibility, despite the assertions of some previous studies. The results of this study improve our knowledge of the relationships between trunk joint flexibility and neuromuscular responses, a relationship which may play a role in low back pain. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Uranium mill tailings

    International Nuclear Information System (INIS)

    McLaren, L.H.

    1982-11-01

    This bibliography contains information on uranium mill tailings included in the Department of Energy's Energy Data Base from January 1981 through October 1982. The abstracts are grouped by subject category as shown in the table of contents. Entries in the subject index also facilitate access by subject, e.g., Mill Tailings/Radiation Hazards. Within each category the arrangement is by report number for reports, followed by nonreports in reverse chronological order. These citations are to research reports, journal articles, books, patents, theses, and conference papers from worldwide sources. Five indexes, each preceded by a brief description, are provided: Corporate Author, Personal Author, Subject, Contract Number, and Report Number. (335 abstracts)

  11. Managing 'tail liability'.

    Science.gov (United States)

    Frese, Richard C; Weber, Ryan J

    2013-11-01

    To reduce and control their level of tail liability, hospitals should: Utilize a self-insurance vehicle; Consider combined limits between the hospital and physicians; Communicate any program changes to the actuary, underwriter, and auditor; Continue risk management and safety practices; Ensure credit is given to the organization's own medical malpractice program.

  12. Accelerated aging tests of liners for uranium mill tailings disposal

    International Nuclear Information System (INIS)

    Barnes, S.M.; Buelt, J.L.; Hale, V.Q.

    1981-11-01

    This document describes the results of accelerated aging tests to determine the long-term effectiveness of selected impoundment liner materials in a uranium mill tailings environment. The study was sponsored by the US Department of Energy under the Uranium Mill Tailings Remedial Action Project. The study was designed to evaluate the need for, and the performance of, several candidate liners for isolating mill tailings leachate in conformance with proposed Environmental Protection Agency and Nuclear Regulatory Commission requirements. The liners were subjected to conditions known to accelerate the degradation mechanisms of the various liners. Also, a test environment was maintained that modeled the expected conditions at a mill tailings impoundment, including ground subsidence and the weight loading of tailings on the liners. A comparison of installation costs was also performed for the candidate liners. The laboratory testing and cost information prompted the selection of a catalytic airblown asphalt membrane and a sodium bentonite-amended soil for fiscal year 1981 field testing

  13. Mine tailings dams: Characteristics, failure, environmental impacts, and remediation

    International Nuclear Information System (INIS)

    Kossoff, D.; Dubbin, W.E.; Alfredsson, M.; Edwards, S.J.; Macklin, M.G.; Hudson-Edwards, K.A.

    2014-01-01

    On a global scale demand for the products of the extractive industries is ever increasing. Extraction of the targeted resource results in the concurrent production of a significant volume of waste material, including tailings, which are mixtures of crushed rock and processing fluids from mills, washeries or concentrators that remain after the extraction of economic metals, minerals, mineral fuels or coal. The volume of tailings is normally far in excess of the liberated resource, and the tailings often contain potentially hazardous contaminants. A priority for a reasonable and responsible mining organization must be to proactively isolate the tailings so as to forestall them from entering groundwaters, rivers, lakes and the wind. There is ample evidence that, should such tailings enter these environments they may contaminate food chains and drinking water. Furthermore, the tailings undergo physical and chemical change after they have been deposited. The chemical changes are most often a function of exposure to atmospheric oxidation and tends to make previously, perhaps safely held contaminants mobile and available. If the tailings are stored under water, contact with the atmosphere is substantially reduced, thereby forestalling oxygen-mediated chemical change. It is therefore accepted practice for tailings to be stored in isolated impoundments under water and behind dams. However, these dams frequently fail, releasing enormous quantities of tailings into river catchments. These accidents pose a serious threat to animal and human health and are of concern for extractive industries and the wider community. It is therefore of importance to understand the nature of the material held within these dams, what best safety practice is for these structures and, should the worst happen, what adverse effects such accidents might have on the wider environment and how these might be mitigated. This paper reviews these factors, covering the characteristics, types and magnitudes

  14. Correlation between the elbow flexion and the hand and wrist flexion after neurotization of the fascicles of the ulnar nerve to the motor branch to the biceps

    Directory of Open Access Journals (Sweden)

    Ricardo Boso Escudero

    Full Text Available ABSTRACT OBJECTIVE: Gain in elbow flexion in patients with brachial plexus injury is extremely important. The transfer of a fascicle from the ulnar nerve to the motor branch of the musculocutaneous nerve (Oberlin surgery is a treatment option. However, in some patients, gain in elbow flexion is associated with wrist and finger flexion. This study aimed to assess the frequency of this association and the functional behavior of the limb. METHODS: Case-control study of 18 patients who underwent the Oberlin surgery. Group 1 included patients without disassociation of range of elbow flexion and that of the fingers and wrist; Group 2 included patients in whom this disassociation was present. In the functional evaluation, the Sollerman and DASH tests were used. RESULTS: It was observed that 38.89% of the patients did not present disassociation of elbow flexion with flexion of the wrist and fingers. Despite the existence of a favorable difference in the group with disassociation of the movement, when the Sollerman protocol was applied to the comparison between both groups, this difference was not statistically significant. With the DASH test, however, there was a statistically significant difference in favor of the group of patients who managed to disassociate the movement. CONCLUSION: The association of elbow flexion with flexion of the wrist and fingers, in the group studied, was shown to be a frequent event, which influenced the functional result of the affected limb.

  15. A flexible wearable sensor for knee flexion assessment during gait.

    Science.gov (United States)

    Papi, Enrica; Bo, Yen Nee; McGregor, Alison H

    2018-05-01

    Gait analysis plays an important role in the diagnosis and management of patients with movement disorders but it is usually performed within a laboratory. Recently interest has shifted towards the possibility of conducting gait assessments in everyday environments thus facilitating long-term monitoring. This is possible by using wearable technologies rather than laboratory based equipment. This study aims to validate a novel wearable sensor system's ability to measure peak knee sagittal angles during gait. The proposed system comprises a flexible conductive polymer unit interfaced with a wireless acquisition node attached over the knee on a pair of leggings. Sixteen healthy volunteers participated to two gait assessments on separate occasions. Data was simultaneously collected from the novel sensor and a gold standard 10 camera motion capture system. The relationship between sensor signal and reference knee flexion angles was defined for each subject to allow the transformation of sensor voltage outputs to angular measures (degrees). The knee peak flexion angle from the sensor and reference system were compared by means of root mean square error (RMSE), absolute error, Bland-Altman plots and intra-class correlation coefficients (ICCs) to assess test-retest reliability. Comparisons of knee peak flexion angles calculated from the sensor and gold standard yielded an absolute error of 0.35(±2.9°) and RMSE of 1.2(±0.4)°. Good agreement was found between the two systems with the majority of data lying within the limits of agreement. The sensor demonstrated high test-retest reliability (ICCs>0.8). These results show the ability of the sensor to monitor knee peak sagittal angles with small margins of error and in agreement with the gold standard system. The sensor has potential to be used in clinical settings as a discreet, unobtrusive wearable device allowing for long-term gait analysis. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

  16. Uranium mill tailings conditioning technology

    International Nuclear Information System (INIS)

    Dreesen, D.R.; Cokal, E.J.; Wangen, L.E.; Williams, J.M.; O'Brien, P.D.; Thode, E.F.

    1982-01-01

    Conditioning of uranium mill tailings involves the physicochemical alteration of tailings to remove or immobilize mobile radionuclides and toxic trace elements before disposal in a repository. The principal immobilization approach under investigation is sintering tailings at high temperatures (1100-1200 deg. C) to radically alter the structure of tailings. This thermal stabilization at 1200 deg. C reduced radon emanation power for tailings sands by factors of 20 to 200 and for tailings fines by factors of 300 to 1100. Substantial reductions in the leachability of most contaminants have been found for thermally conditioned tailings. Obvious mineral transformations occur, including an increase in amorphous material, the conversion of gypsum to anhydrite and its subsequent decomposition, the disappearance of clay minerals, and some decrease in quartz content. A conceptual thermal stabilization process has been developed wherein obsolete coal-fired rotary cement kilns perform the sintering. An economic analysis of this conceptual process has shown that thermal stabilization can be competitive at certain tailings sites with other remedial actions requiring the excavation, transportation, and burial of tailings in a repository. An analysis of the long-term radiological hazard posed by untreated tailings and by tailings conditioned by radionuclide removal has illustrated the necessity of extracting both 226 Ra and 230 Th to achieve long-term hazard reductions. Sulphuric acid extraction of residual mineral values and important radionuclides from tailings has been investigated. Concentrated H 2 SO 4 can extract up to 80% of the 226 Ra, 70% of the Ba, and 90% of the 230 Th from tailings in a single stage extraction. An economic analysis of a sulphuric acid leach process was made to determine whether the value of minerals recovered from tailings would offset the leaching cost. For one relatively mineral-rich tailings pile, the U and V values would more than pay for the

  17. Telling tails: selective pressures acting on investment in lizard tails.

    Science.gov (United States)

    Fleming, Patricia A; Valentine, Leonie E; Bateman, Philip W

    2013-01-01

    Caudal autotomy is a common defense mechanism in lizards, where the animal may lose part or all of its tail to escape entrapment. Lizards show an immense variety in the degree of investment in a tail (i.e., length) across species, with tails of some species up to three or four times body length (snout-vent length [SVL]). Additionally, body size and form also vary dramatically, including variation in leg development and robustness and length of the body and tail. Autotomy is therefore likely to have fundamentally different effects on the overall body form and function in different species, which may be reflected directly in the incidence of lost/regenerating tails within populations or, over a longer period, in terms of relative tail length for different species. We recorded data (literature, museum specimens, field data) for relative tail length (n=350 species) and the incidence of lost/regenerating tails (n=246 species). We compared these (taking phylogeny into account) with intrinsic factors that have been proposed to influence selective pressures acting on caudal autotomy, including body form (robustness, body length, leg development, and tail specialization) and ecology (foraging behavior, physical and temporal niches), in an attempt to identify patterns that might reflect adaptive responses to these different factors. More gracile species have relatively longer tails (all 350 spp., P lost/regenerating tails for nocturnal lizards (all 246 spp., P pressure.

  18. A Glimpse of the genomic diversity of haloarchaeal tailed viruses

    Directory of Open Access Journals (Sweden)

    Ana eSencilo

    2014-03-01

    Full Text Available Tailed viruses are the most common isolates infecting prokaryotic hosts residing hypersaline environments. Archaeal tailed viruses represent only a small portion of all characterized tailed viruses of prokaryotes. But even this small dataset revealed that archaeal tailed viruses have many similarities to their counterparts infecting bacteria, the bacteriophages. Shared functional homologues and similar genome organizations suggested that all microbial tailed viruses have common virion architectural and assembly principles. Recent structural studies have provided evidence justifying this thereby grouping archaeal and bacterial tailed viruses into a single lineage. Currently there are 17 haloarchaeal tailed viruses with entirely sequenced genomes. Nine viruses have at least one close relative among the 17 viruses and, according to the similarities, can be divided into three groups. Two other viruses share some homologues and therefore are distantly related, whereas the rest of the viruses are rather divergent (or singletons. Comparative genomics analysis of these viruses offers a glimpse into the genetic diversity and structure of haloarchaeal tailed virus communities.

  19. Uranium tailings in Canada

    International Nuclear Information System (INIS)

    Boulden, R.S.; Bragg, K.

    1982-01-01

    The last few years have produced significant changes in the way uranium tailings are managed in Canada. This is due both to the development of new technology and to changes in regulatory approach. The interrelationships between these two areas are examined with particular attention paid to the long term and the development of close-out criteria. New technological initiatives are examined including dry placement techniques, pit disposal and deep lake disposal

  20. Velocity of lordosis angle during spinal flexion and extension.

    Directory of Open Access Journals (Sweden)

    Tobias Consmüller

    Full Text Available The importance of functional parameters for evaluating the severity of low back pain is gaining clinical recognition, with evidence suggesting that the angular velocity of lordosis is critical for identification of musculoskeletal deficits. However, there is a lack of data regarding the range of functional kinematics (RoKs, particularly which include the changing shape and curvature of the spine. We address this deficit by characterising the angular velocity of lordosis throughout the thoracolumbar spine according to age and gender. The velocity of lumbar back shape changes was measured using Epionics SPINE during maximum flexion and extension activities in 429 asymptomatic volunteers. The difference between maximum positive and negative velocities represented the RoKs. The mean RoKs for flexion decreased with age; 114°/s (20-35 years, 100°/s (36-50 years and 83°/s (51-75 years. For extension, the corresponding mean RoKs were 73°/s, 57°/s and 47°/s. ANCOVA analyses revealed that age and gender had the largest influence on the RoKs (p<0.05. The Epionics SPINE system allows the rapid assessment of functional kinematics in the lumbar spine. The results of this study now serve as normative data for comparison to patients with spinal pathology or after surgical treatment.

  1. Nociceptive flexion reflexes during analgesic neurostimulation in man.

    Science.gov (United States)

    García-Larrea, L; Sindou, M; Mauguière, F

    1989-11-01

    Nociceptive flexion reflexes of the lower limbs (RIII responses) have been studied in 21 patients undergoing either epidural (DCS, n = 16) or transcutaneous (TENS, n = 5) analgesic neurostimulation (AN) for chronic intractable pain. Flexion reflex RIII was depressed or suppressed by AN in 11 patients (52.4%), while no modification was observed in 9 cases and a paradoxical increase during AN was evidenced in 1 case. In all but 2 patients, RIII changes were rapidly reversible after AN interruption. RIII depression was significantly associated with subjective pain relief, as assessed by conventional self-rating; moreover, in 2 patients it was possible to ameliorate the pain-suppressing effects of AN by selecting those stimulation parameters (intensity and frequency) that maximally depressed nociceptive reflex RIII. We recorded 2 cases of RIII attenuation after contralateral neurostimulation. AN appeared to affect nociceptive reflexes rather selectively, with no or very little effect on other cutaneous, non-nociceptive responses. Recording of RIII reflexes is relatively simple to implement as a routine paraclinical procedure. It facilitates the objective assessment of AN efficacy and may help to choose the most appropriate parameters of neurostimulation. In addition, RIII behavior in patients could be relevant to the understanding of some of the mechanisms involved in AN-induced pain relief.

  2. Magnetic resonance imaging of the posterior cruciate ligament in flexion.

    Science.gov (United States)

    Craddock, William; Smithers, Troy; Harris, Craig; du Moulin, William; Molnar, Robert

    2018-06-01

    Posterior cruciate ligament (PCL) injuries of the knee are common and sometimes difficult to diagnose. Magnetic resonance imaging (MRI), performed using standard orthogonal plane views, is the investigation of choice. It can be particularly difficult to differentiate acute partial and complete tears and identify elongation of chronic healed tears. The aim of the paper is to describe a new method of positioning the patient with the knee flexed at 90°, allowing the PCL to be visualised in a position of greatest length and tension which may assist in differentiating and identifying these injuries. Four symptomatic patients with suspected PCL injuries, two acute and two chronic, were MRI scanned using a routine protocol with the knee in extension before performing oblique sagittal fast spin-echo (FSE) proton-density (PD) sequences with the knee positioned in 90° of flexion. The appearance of the PCLs were then qualitatively assessed. MRI scanning with the knee in flexion identified more extensive PCL injury than standard imaging. In the two patients with acute injuries, partial tears on the standard orthogonal plane views were found to be complete ruptures. In the two patients with chronic injuries, elongation of the PCL not identifiable on the standard orthogonal plane views was apparent. MRI scanning of the PCL with the knee flexed at 90° may help in differentiating partial and complete ruptures of the PCL and identifying elongation of the PCL in chronic injuries. Copyright © 2018 Elsevier B.V. All rights reserved.

  3. Entretien sur la psychanalyse: réflexions en marge

    Directory of Open Access Journals (Sweden)

    Giuseppe Martini

    2016-08-01

    Full Text Available L’auteur propose ici un commentaire sur les points les plus importants de son entretien de février 2003 avec Paul Ricœur consacré aux rapports entre herméneutique et psychanalyse. Bien que le philosophe se situe dans une réelle continuité par rapport à sa contribution de 1965, il enrichit toutefois sa réflexion philosophique sur la psychanalyse en proposant plusieurs innovations, en ce qui concerne plus particulièrement les thèmes du récit, du soi et de l’éthique. Dans les conclusions de son commentaire, l’auteur souligne l’importance des concepts d’“irreprésentable” et d’“intraduisible”: non seulement, en effet, ces concepts sont dans la ligne de nombreuses contributions de la psychanalyse contemporaine, mais la profondeur de la réflexion ricœurienne augmente en outre leur potentiel théorique et même clinique.

  4. Orphan Stars Found in Long Galaxy Tail

    Science.gov (United States)

    2007-09-01

    Astronomers have found evidence that stars have been forming in a long tail of gas that extends well outside its parent galaxy. This discovery suggests that such "orphan" stars may be much more prevalent than previously thought. The comet-like tail was observed in X-ray light with NASA's Chandra X-ray Observatory and in optical light with the Southern Astrophysical Research (SOAR) telescope in Chile. The feature extends for more than 200,000 light years and was created as gas was stripped from a galaxy called ESO 137-001 that is plunging toward the center of Abell 3627, a giant cluster of galaxies. "This is one of the longest tails like this we have ever seen," said Ming Sun of Michigan State University, who led the study. "And, it turns out that this is a giant wake of creation, not of destruction." Chandra X-ray Image of ESO 137-001 and Tail in Abell 3627 Chandra X-ray Image of ESO 137-001 and Tail in Abell 3627 The observations indicate that the gas in the tail has formed millions of stars. Because the large amounts of gas and dust needed to form stars are typically found only within galaxies, astronomers have previously thought it unlikely that large numbers of stars would form outside a galaxy. "This isn't the first time that stars have been seen to form between galaxies," said team member Megan Donahue, also of MSU. "But the number of stars forming here is unprecedented." The evidence for star formation in this tail includes 29 regions of ionized hydrogen glowing in optical light, thought to be from newly formed stars. These regions are all downstream of the galaxy, located in or near the tail. Two Chandra X-ray sources are near these regions, another indication of star formation activity. The researchers believe the orphan stars formed within the last 10 million years or so. The stars in the tail of this fast-moving galaxy, which is some 220 million light years away, would be much more isolated than the vast majority of stars in galaxies. H-alpha Image of

  5. Injurious tail biting in pigs

    DEFF Research Database (Denmark)

    D'Eath, R.B.; Amott, G.; Turner, S. P.

    2014-01-01

    not allow tail docking at all. Against this background, using a novel approach focusing on research where tail injuries were quantified, we review the measures that can be used to control tail biting in pigs without tail docking. Using this strict criterion, there was good evidence that manipulable...... substrates and feeder space affect damaging tail biting. Only epidemiological evidence was available for effects of temperature and season, and the effect of stocking density was unclear. Studies suggest that group size has little effect, and the effects of nutrition, disease and breed require further...... underlying processes of tail biting. A quantitative comparison of the efficacy of different methods of provision of manipulable materials, and a review of current practices in countries and assurance schemes where tail docking is banned, both suggest that daily provision of small quantities of destructible...

  6. [Research progress of larger flexion gap than extension gap in total knee arthroplasty].

    Science.gov (United States)

    Zhang, Weisong; Hao, Dingjun

    2017-05-01

    To summarize the progress of larger flexion gap than extension gap in total knee arthro-plasty (TKA). The domestic and foreign related literature about larger flexion gap than extension gap in TKA, and its impact factors, biomechanical and kinematic features, and clinical results were summarized. During TKA, to adjust the relations of flexion gap and extension gap is one of the key factors of successful operation. The biomechanical, kinematic, and clinical researches show that properly larger flexion gap than extension gap can improve both the postoperative knee range of motion and the satisfaction of patients, but does not affect the stability of the knee joint. However, there are also contrary findings. So adjustment of flexion gap and extension gap during TKA is still in dispute. Larger flexion gap than extension gap in TKA is a new joint space theory, and long-term clinical efficacy, operation skills, and related complications still need further study.

  7. Flexion relaxation of the hamstring muscles during lumbar-pelvic rhythm.

    Science.gov (United States)

    Sihvonen, T

    1997-05-01

    This study investigated the simultaneous activity of back muscles and hamstring muscles during sagittal forward body flexion and extension in healthy persons. The study was cross-sectional. A descriptive study of paraspinal and hamstring muscle activity in normal persons during lumbar-pelvic rhythm. A university hospital. Forty healthy volunteers (21 men, 19 women, ages 17 to 48 years), all without back pain or other pain syndromes. Surface electromyography (EMG) was used to follow activities in the back and the hamstring muscles. With movement sensors, real lumbar flexion was separated from simultaneous pelvic motion by monitoring the components of motion with a two-inclinometer method continuously from the initial upright posture into full flexion. All signals were sampled during real-time monitoring for off-line analyses. Back muscle activity ceased (ie, flexion relaxation [FR] occurred) at lumbar flexion with a mean of 79 degrees. Hamstring activity lasted longer and EMG activity ceased in the hamstrings when nearly full lumbar flexion (97%) was reached. After this point total flexion and pelvic flexion continued further, so that the last part of lumbar flexion and the last part of pelvic flexion happened without back muscle activity or hamstring bracing, respectively. FR of the back muscles during body flexion has been well established and its clinical significance in low back pain has been confirmed. In this study, it was shown for the first time that the hip extensors (ie, hamstring muscles) relax during forward flexion but with different timing. FR in hamstrings is not dependent on or coupled firmly with back muscle behavior in spinal disorders and the lumbar pelvic rhythm can be locally and only partially disturbed.

  8. The Arterial Folding Point During Flexion of the Hip Joint

    International Nuclear Information System (INIS)

    Park, Sung Il; Won, Je Hwan; Kim, Byung Moon; Kim, Jae Keun; Lee, Do Yun

    2005-01-01

    Purpose: Endovascular stents placed in periarticular vessels may be at a greater risk of neointimal hyperplasia and eventual occlusion than those placed in non-periarticular vessels. The purpose of this study was to investigate the location of maximal conformational change along the iliac and femoral artery, the folding point, during flexion of the hip joint and its location relative to the hip joint and the inguinal ligament. Methods: Seventy patients undergoing femoral artery catheterization were evaluated. The patients were 47 men and 23 women and ranged in age from 26 to 75 years (mean 54 years). The arteries (right:left = 34:36) were measured using a marked catheter for sizing vessels. Fluoroscopic images were obtained in anteroposterior and lateral projections in neutral position, and in the lateral projection in flexed position of the hip joint. The folding point was determined by comparing the lateral projection images in the neutral and flexed positions. The distance from the acetabular roof to the folding point and the distance from the inguinal ligament to the folding point was evaluated. Results: : The folding point was located 42.8 ± 28.6 mm cranial to the acetabular roof and 35.1 ± 30.1 mm cranial to the inguinal ligament. As the patient’s age increased, the folding point was located more cranially (p < 0.001). Conclusions: The folding point during flexion of the hip joint was located 42.8 ± 28.6 mm cranial to the acetabular roof and 35.1 ± 30.1 mm cranial to the inguinal ligament. As the patient's age increased, the folding point was located more cranially. When a stent is inserted over this region, more attention may be needed during follow-up to monitor possible occlusion and stent failure.

  9. Settlement of uranium mill tailings

    International Nuclear Information System (INIS)

    Chen, P.K.; Guros, F.B.; Keshian, B.

    1988-01-01

    Two test embankments were constructed on top of an old tailings deposit near Ambrosia Lake, New Mexico to determine settlement characteristics of hydraulically- deposited uranium mill tailings. Before construction of the embankments, properties of in-situ tailings and foundation soils were determined using data from boreholes, piezocone soundings, and laboratory tests. These properties were used to estimate post-construction settlement of a planned disposal embankment to be constructed on the tailings. However, excessive uncertainty existed in the following: field settlement rates of saturated and unsaturated tailings, degree of preconsolidation of the upper 15 feet of tailings, and the ability of an underlying silty sand foundation layer to facilitate drainage. Thus, assurance could not be provided that differential settlements of the radon barrier and erosion protection layers would be within allowable limits should the planned disposal embankment be constructed in a single-stage

  10. Copper tailings in stucco mortars

    Directory of Open Access Journals (Sweden)

    Osvaldo Pavez

    Full Text Available Abstract This investigation addressed the evaluation of the use of copper tailings in the construction industry in order to reduce the impact on the environment. The evaluation was performed by a technical comparison between stucco mortars prepared with crushed conventional sand and with copper tailings sand. The best results were achieved with the stucco mortars containing tailings. The tailings presented a fine particles size distribution curve different from that suggested by the standard. The values of compressive strength, retentivity, and adherence in the stucco mortars prepared with copper tailings were much higher than those obtained with crushed sand. According to the results from this study, it can be concluded that the preparation of stucco mortars using copper tailings replacing conventional sand is a technically feasible alternative for the construction industry, presenting the benefit of mitigating the impact of disposal to the environment.

  11. Uranium tailings reference materials

    International Nuclear Information System (INIS)

    Smith, C.W.; Steger, H.F.; Bowman, W.S.

    1984-01-01

    Samples of uranium tailings from Bancroft and Elliot Lake, Ontario, and from Beaverlodge and Rabbit Lake, Saskatchewan, have been prepared as compositional reference materials at the request of the National Uranium Tailings Research Program. The four samples, UTS-1 to UTS-4, were ground to minus 104 μm, each mixed in one lot and bottled in 200-g units for UTS-1 to UTS-3 and in 100-g units for UTS-4. The materials were tested for homogeneity with respect to uranium by neutron activation analysis and to iron by an acid-decomposition atomic absorption procedure. In a free choice analytical program, 18 laboratories contributed results for one or more of total iron, titanium, aluminum, calcium, barium, uranium, thorium, total sulphur, and sulphate for all four samples, and for nickel and arsenic in UTS-4 only. Based on a statistical analysis of the data, recommended values were assigned to all elements/constituents, except for sulphate in UTS-3 and nickel in UTS-4. The radioactivity of thorium-230, radium-226, lead-210, and polonium-210 in UTS-1 to UTS-4 and of thorium-232, radium-228, and thorium-228 in UTS-1 and UTS-2 was determined in a radioanalytical program composed of eight laboratories. Recommended values for the radioactivities and associated parameters were calculated by a statistical treatment of the results

  12. Bioassay for uranium mill tailings

    International Nuclear Information System (INIS)

    Tschaeche, A.N.

    1986-01-01

    Uranium mill tailings are composed of fine sand that contains, among other things, some uranium (U/sup 238/ primarily), and all of the uranium daughters starting with /sup 230/Th that are left behind after the usable uranium is removed in the milling process. Millions of pounds of tailings are and continue to be generated at uranium mills around the United States. Discrete uranium mill tailings piles exist near the mills. In addition, the tailings materials were used in communities situated near mill sites for such purposes as building materials, foundations for buildings, pipe runs, sand boxes, gardens, etc. The Uranium Mill Tailings Remedial Action Project (UMTRAP) is a U.S. Department of Energy Program designed with the intention of removing or stabilizing the mill tailings piles and the tailings used to communities so that individuals are not exposed above the EPA limits established for such tailings materials. This paper discusses the bioassay programs that are established for workers who remove tailings from the communities in which they are placed

  13. Uranium mill tailings and radon

    International Nuclear Information System (INIS)

    Hanchey, L.A.

    1981-01-01

    The major health hazard from uranium mill tailings is presumed to be respiratory cancer resulting from the inhalation of radon daughter products. A review of studies on inhalation of radon and its daughters indicates that the hazard from the tailings is extremely small. If the assumptions used in the studies are correct, one or two people per year in the US may develop cancer as a result of radon exhaled from all the Uranium Mill Tailings Remedial Action Program sites. The remedial action should reduce the hazard from the tailings by a factor of about 100

  14. Uranium mill tailings and radon

    Energy Technology Data Exchange (ETDEWEB)

    Hanchey, L A

    1981-04-01

    The major health hazard from uranium mill tailings is presumed to be respiratory cancer resulting from the inhalation of radon daughter products. A review of studies on inhalation of radon and its daughters indicates that the hazard from the tailings is extremely small. If the assumptions used in the studies are correct, one or two people per year in the United States may develop cancer as a result of radon exhaled from all the Uranium Mill Tailings Remedial Action program sites. The remedial action should reduce the hazard from the tailings by a factor of about 100.

  15. Uranium mill tailings and radon

    Energy Technology Data Exchange (ETDEWEB)

    Hanchey, L A

    1981-01-01

    The major health hazard from uranium mill tailings is presumed to be respiratory cancer resulting from the inhalation of radon daughter products. A review of studies on inhalation of radon and its daughters indicates that the hazard from the tailings is extremely small. If the assumptions used in the studies are correct, one or two people per year in the US may develop cancer as a result of radon exhaled from all the Uranium Mill Tailings Remedial Action Program sites. The remedial action should reduce the hazard from the tailings by a factor of about 100.

  16. TAIL ASYMPTOTICS OF LIGHT-TAILED WEIBULL-LIKE SUMS

    DEFF Research Database (Denmark)

    Asmussen, Soren; Hashorva, Enkelejd; Laub, Patrick J.

    2017-01-01

    We consider sums of n i.i.d. random variables with tails close to exp{-x(beta)} for some beta > 1. Asymptotics developed by Rootzen (1987) and Balkema, Kluppelberg, and Resnick (1993) are discussed from the point of view of tails rather than of densities, using a somewhat different angle...

  17. Effects of weather and tailings properties on tailings drying times

    Energy Technology Data Exchange (ETDEWEB)

    Gantzer, C.; Fasking, T.; Costello, M.; Greenwood, J. [Barr Engineering, Calgary, AB (Canada)

    2010-07-01

    This PowerPoint presentation presented the results of a study conducted to determine the effects of weather and tailings properties on tailings drying times. Weather conditions have a significant impact the potential evaporation (PE) and actual evaporation (AE) of oil sands tailings. A 2-stage drying of slurry at a constant PE was conducted to determine the shrinkage limit of untreated mature fine tailings (MFT). An evaporation and seepage model was used to determine maximum first-stage drying rates. Measurements were also taken in a wind tunnel. Potential evaporation rates were calculated and evaporative water losses from the MFT were determined. Estimated drying times were presented. Results of the approach were compared with field measurements conducted in a previous study. Results of the study showed that evaporative water loss rates for May through August were limited by the properties of the tailings. Water loss rates were limited by weather for other months in the year-long study. tabs., figs.

  18. The Effects of Psoas Major and Lumbar Lordosis on Hip Flexion and Sprint Performance

    Science.gov (United States)

    Copaver, Karine; Hertogh, Claude; Hue, Olivier

    2012-01-01

    In this study, we analyzed the correlations between hip flexion power, sprint performance, lumbar lordosis (LL) and the cross-sectional area (CSA) of the psoas muscle (PM). Ten young adults performed two sprint tests and isokinetic tests to determine hip flexion power. Magnetic resonance imaging was used to determine LL and PM CSA. There were…

  19. Repeatability of cervical joint flexion and extension within and between days

    DEFF Research Database (Denmark)

    Wang, Xu; Lindstroem, René; Plocharski, Maciej

    2018-01-01

    OBJECTIVE: The purpose of this study was to investigate within- and between-day repeatability of free and unrestricted healthy cervical flexion and extension motion when assessing dynamic cervical spine motion. METHODS: Fluoroscopy videos of 2 repeated cervical flexion and 2 repeated extension...

  20. Angioleiomyoma: A Rare Cause of Fixed Flexion Contracture of the Elbow

    Directory of Open Access Journals (Sweden)

    Asterios Dramis

    2006-01-01

    Full Text Available We describe an unusual case of a patient presented with a painless fixed flexion contracture of the elbow due to an angioleiomyoma. This benign smooth muscle tumour should be considered in the differential diagnosis of flexion contractures of the elbow.

  1. Posterior-anterior weight-bearing radiograph in 15 knee flexion in medial osteoarthritis

    International Nuclear Information System (INIS)

    Yamanaka, Norio; Takahashi, Toshiaki; Yamamoto, Hiroshi; Ichikawa, Norikazu

    2003-01-01

    To evaluate the degree of knee flexion at which: (1) degenerative joint space narrowing is best seen, (2) the tibial plateau is best visualized and (3) the tibiofemoral angle is most correct, in order to assess the degree of flexion in the anteroposterior radiographic view that is most useful for assessing medial compartment osteoarthritis (OA) of the knee.Design and patients. We compared the conventional extended view of the knee and views at 15 , 30 , and 45 of flexion with respect to joint space narrowing, alignment of the medial tibial plateau (MTP), and tibiofemoral angles in 113 knees of 95 patients with medial osteoarthritis of the knee (22 men, 73 women; mean age 67 years).Results. At the midpoint and the narrowest point of the medial compartment, joint space narrowing values at 15 , 30 , and 45 of flexion of the knee were smaller than that of the conventional extended view. Superimposition of the margins of the tibial plateau was satisfactory in 12% of patients in the conventional extended view, in 36% at 15 of flexion, in 20% at 30 of flexion, and in 19% at 45 of flexion of the knee. When the knee was at 15 of flexion there was a smaller difference in the tibiofemoral angle, in comparison with the knee extended, than was the case at 30 and 45 of flexion in patients with medial OA.Conclusion. A posteroanterior view with 15 of flexion of the knee was able to detect joint space narrowing accurately, to achieve good alignment of the MTP in the medial compartment, and to reduce the difference in tibiofemoral angle compared with a view of the knee in conventional extension, and may be an alternative view in cases of medial OA of the knee. (orig.)

  2. Runaway tails in magnetized plasmas

    Science.gov (United States)

    Moghaddam-Taaheri, E.; Vlahos, L.; Rowland, H. L.; Papadopoulos, K.

    1985-01-01

    The evolution of a runaway tail driven by a dc electric field in a magnetized plasma is analyzed. Depending on the strength of the electric field and the ratio of plasma to gyrofrequency, there are three different regimes in the evolution of the tail. The tail can be (1) stable with electrons accelerated to large parallel velocities, (2) unstable to Cerenkov resonance because of the depletion of the bulk and the formation of a positive slope, (3) unstable to the anomalous Doppler resonance instability driven by the large velocity anisotropy in the tail. Once an instability is triggered (Cerenkov or anomalous Doppler resonance) the tail relaxes into an isotropic distribution. The role of a convection type loss term is also discussed.

  3. Poly A tail length analysis of in vitro transcribed mRNA by LC-MS.

    Science.gov (United States)

    Beverly, Michael; Hagen, Caitlin; Slack, Olga

    2018-02-01

    The 3'-polyadenosine (poly A) tail of in vitro transcribed (IVT) mRNA was studied using liquid chromatography coupled to mass spectrometry (LC-MS). Poly A tails were cleaved from the mRNA using ribonuclease T1 followed by isolation with dT magnetic beads. Extracted tails were then analyzed by LC-MS which provided tail length information at single-nucleotide resolution. A 2100-nt mRNA with plasmid-encoded poly A tail lengths of either 27, 64, 100, or 117 nucleotides was used for these studies as enzymatically added poly A tails showed significant length heterogeneity. The number of As observed in the tails closely matched Sanger sequencing results of the DNA template, and even minor plasmid populations with sequence variations were detected. When the plasmid sequence contained a discreet number of poly As in the tail, analysis revealed a distribution that included tails longer than the encoded tail lengths. These observations were consistent with transcriptional slippage of T7 RNAP taking place within a poly A sequence. The type of RNAP did not alter the observed tail distribution, and comparison of T3, T7, and SP6 showed all three RNAPs produced equivalent tail length distributions. The addition of a sequence at the 3' end of the poly A tail did, however, produce narrower tail length distributions which supports a previously described model of slippage where the 3' end can be locked in place by having a G or C after the poly nucleotide region. Graphical abstract Determination of mRNA poly A tail length using magnetic beads and LC-MS.

  4. "Popeye muscle" morphology in OBPI elbow flexion contracture.

    Science.gov (United States)

    Coroneos, Christopher J; Maizlin, Zeev V; DeMatteo, Carol; Gjertsen, Deborah; Bain, James R

    2015-01-01

    The pathophysiology of elbow flexion contracture (EFC) in obstetrical brachial plexus injury (OBPI) is not established. In basic science models, neonatal denervation leads to impaired muscle growth. In clinical studies, diminished growth is correlated with extent of denervation, and improved with surgical repair. In EFC, the biceps are clinically short and round vs the contralateral size, termed the "Popeye muscle". The objective of this study was to determine if the biceps morphology (muscle belly and tendon length) in arms with EFC secondary to OBPI is different vs the contralateral. This is a retrospective matched-cohort study. Patients with unilateral EFC (>20°) secondary to OBPI were identified (median = 6.6 years, range = 4.7-16.8). A blinded radiologist used computed tomography to measure length of the biceps short head muscle belly, and tendon bilaterally using standardised anatomical landmarks. Twelve patients were analyzed. The biceps muscle belly in the injured arm was shorter in all patients vs contralateral, mean difference = 3.6 cm (80%), p muscle belly and overall length, but longer tendon vs normal. This is termed the "Popeye muscle" for its irregular morphology. Findings are consistent with impaired limb growth in denervation.

  5. Long-term stabilization of uranium mill tailings

    International Nuclear Information System (INIS)

    Voorhees, L.D.; Sale, M.J.; Webb, J.W.; Mulholland, P.J.

    1983-01-01

    The primary hazard associated with uranium mill tailings is exposure to a radioactive gas, radon-222, the concentration of which has been correlated with the occurrence of lung cancer. Previous studies on radon attenuation conclude that the placement of earthen cover materials over the tailings is the most effective technique for reducing radioactive emissions and dispersal of tailings. The success of such a plan, however, is dependent on ensuring the long-term integrity of these cover materials. Soil erosion from water and wind is the major natural cause of destabilizing earthen cover materials. Field data related to the control of soil loss are limited and only indirectly apply to the problem of isolation of uranium mill tailings over very long time periods (up to 80,000 a). However, sufficient information is available to determine benefits that will result from the changes in specific design variables and to evaluate the need for different design strategies among potential disposal sites. The three major options available for stabilization of uranium mill tailings are: rock cover, soil and revegetation, or a combination of both on different portions of the tailings cover. The optimal choice among these alternatives depends on site-specific characteristics such as climate and local geomorphology and soils, and on design variables such as embankment, heights and slopes, modification of upstream drainage, and revegetation practices. Generally, geomorphic evidence suggests that use of soil and vegetation alone will not be adequate to reduce erosion on slopes greater than about 5 to 9%

  6. Clinical Evaluation of Fused/Ankylosed Hip with Severe Flexion Deformity after Conversion to Total Hip Arthroplasty

    Directory of Open Access Journals (Sweden)

    Saroj Kumar Suwal

    2016-06-01

    Conclusions: THA is an effective treatment for ankylosed hip with severe flexion deformity although complications are noted more than routine hip arthroplasties. Keywords: ankylosed hip; fused hip; severe flexion deformity; total hip arthroplasty. | PubMed

  7. Relative sensitivity of depth discrimination for ankle inversion and plantar flexion movements.

    Science.gov (United States)

    Black, Georgia; Waddington, Gordon; Adams, Roger

    2014-02-01

    25 participants (20 women, 5 men) were tested for sensitivity in discrimination between sets of six movements centered on 8 degrees, 11 degrees, and 14 degrees, and separated by 0.3 degrees. Both inversion and plantar flexion movements were tested. Discrimination of the extent of inversion movement was observed to decline linearly with increasing depth; however, for plantar flexion, the discrimination function for movement extent was found to be non-linear. The relatively better discrimination of plantar flexion movements than inversion movements at around 11 degrees from horizontal is interpreted as an effect arising from differential amounts of practice through use, because this position is associated with the plantar flexion movement made in normal walking. The fact that plantar flexion movements are discriminated better than inversion at one region but not others argues against accounts of superior proprioceptive sensitivity for plantar flexion compared to inversion that are based on general properties of plantar flexion such as the number of muscle fibres on stretch.

  8. The effect of posterior tibial slope on knee flexion in posterior-stabilized total knee arthroplasty.

    Science.gov (United States)

    Shi, Xiaojun; Shen, Bin; Kang, Pengde; Yang, Jing; Zhou, Zongke; Pei, Fuxing

    2013-12-01

    To evaluate and quantify the effect of the tibial slope on the postoperative maximal knee flexion and stability in the posterior-stabilized total knee arthroplasty (TKA). Fifty-six patients (65 knees) who had undergone TKA with the posterior-stabilized prostheses were divided into the following 3 groups according to the measured tibial slopes: Group 1: ≤4°, Group 2: 4°-7° and Group 3: >7°. The preoperative range of the motion, the change in the posterior condylar offset, the elevation of the joint line, the postoperative tibiofemoral angle and the preoperative and postoperative Hospital for Special Surgery (HSS) scores were recorded. The tibial anteroposterior translation was measured using the Kneelax 3 Arthrometer at both the 30° and the 90° flexion angles. The mean values of the postoperative maximal knee flexion were 101° (SD 5), 106° (SD 5) and 113° (SD 9) in Groups 1, 2 and 3, respectively. A significant difference was found in the postoperative maximal flexion between the 3 groups (P slope resulted in a 1.8° flexion increment (r = 1.8, R (2) = 0.463, P slope can significantly increase the postoperative maximal knee flexion. The tibial slope with an appropriate flexion and extension gap balance during the operation does not affect the joint stability.

  9. Biomechanical Considerations in the Design of High-Flexion Total Knee Replacements

    Directory of Open Access Journals (Sweden)

    Cheng-Kung Cheng

    2014-01-01

    Full Text Available Typically, joint arthroplasty is performed to relieve pain and improve functionality in a diseased or damaged joint. Total knee arthroplasty (TKA involves replacing the entire knee joint, both femoral and tibial surfaces, with anatomically shaped artificial components in the hope of regaining normal joint function and permitting a full range of knee flexion. In spite of the design of the prosthesis itself, the degree of flexion attainable following TKA depends on a variety of factors, such as the joint’s preoperative condition/flexion, muscle strength, and surgical technique. High-flexion knee prostheses have been developed to accommodate movements that require greater flexion than typically achievable with conventional TKA; such high flexion is especially prevalent in Asian cultures. Recently, computational techniques have been widely used for evaluating the functionality of knee prostheses and for improving biomechanical performance. To offer a better understanding of the development and evaluation techniques currently available, this paper aims to review some of the latest trends in the simulation of high-flexion knee prostheses.

  10. Mercury's Dynamic Magnetic Tail

    Science.gov (United States)

    Slavin, James A.

    2010-01-01

    The Mariner 10 and MESSENGER flybys of Mercury have revealed a magnetosphere that is likely the most responsive to upstream interplanetary conditions of any in the solar system. The source of the great dynamic variability observed during these brief passages is due to Mercury's proximity to the Sun and the inverse proportionality between reconnection rate and solar wind Alfven Mach number. However, this planet's lack of an ionosphere and its small physical dimensions also contribute to Mercury's very brief Dungey cycle, approx. 2 min, which governs the time scale for internal plasma circulation. Current observations and understanding of the structure and dynamics of Mercury's magnetotail are summarized and discussed. Special emphasis will be placed upon such questions as: 1) How much access does the solar wind have to this small magnetosphere as a function of upstream conditions? 2) What roles do heavy planetary ions play? 3) Do Earth-like substorms take place at Mercury? 4) How does Mercury's tail respond to extreme solar wind events such coronal mass ejections? Prospects for progress due to advances in the global magnetohydrodynamic and hybrid simulation modeling and the measurements to be taken by MESSENGER after it enters Mercury orbit on March 18, 2011 will be discussed.

  11. Balanced Flexion and Extension Gaps Are Not Always of Equal Size.

    Science.gov (United States)

    Kinsey, Tracy L; Mahoney, Ormonde M

    2018-04-01

    It has been widely accepted in total knee arthroplasty (TKA) that flexion and extension gaps in the disarticulated knee during surgery should be equalized. We hypothesized that tensioning during assessment of the flexion gap can induce temporary widening of the gap due to posterior tibial translation. We aimed to describe posterior tibial translation at flexion gap (90°) assessments and assess the correlation of tibial translation with laxity (flexion space increase) using constrained and non-constrained inserts. Imageless navigation was used to measure flexion angle, tibial position relative to the femoral axis, and lateral/medial laxity in 30 patients undergoing primary TKA. Trialing was conducted using posteriorly stabilized and cruciate retaining trials of the same size to elucidate the association of posterior tibial translation with changes in joint capsule laxity at 90° knee flexion. All patients demonstrated posterior tibial translation during flexion gap assessment relative to their subsequent final implantation [mean ± standard deviation (range), 11.3 ± 4.4 (4-21) mm]. Positive linear correlation [r = 0.69, 95% confidence interval (CI) 0.44-0.84, P ≤ .001] was demonstrated between translations [8.7 ± 2.4 (3-13) mm] and laxity changes [2.9° ± 2.0° (-0.7° to 7.4°)] at 90° of flexion. Posterior tibial translation can cause artifactual widening of the flexion gap during gap balancing in posteriorly stabilized TKA, which can be of sufficient magnitude to alter femoral component size selection for some patients. Recognition and management of these intra-operative dynamics for optimal kinematics could be feasible with the advent of robotic applications. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Comparative study of phrenic and intercostal nerve transfers for elbow flexion after global brachial plexus injury.

    Science.gov (United States)

    Liu, Yuzhou; Lao, Jie; Zhao, Xin

    2015-04-01

    Global brachial plexus injuries (BPIs) are devastating events frequently resulting in severe functional impairment. The widely used nerve transfer sources for elbow flexion in patients with global BPIs include intercostal and phrenic nerves. The aim of this study was to compare phrenic and intercostal nerve transfers for elbow flexion after global BPI. A retrospective review of 33 patients treated with phrenic and intercostal nerve transfer for elbow flexion in posttraumatic global root avulsion BPI was carried out. In the phrenic nerve transfer group, the phrenic nerve was transferred to the anterolateral bundle of the anterior division of the upper trunk (23 patients); in the intercostal nerve transfer group, three intercostal nerves were coapted to the anterolateral bundles of the musculocutaneous nerve. The British Medical Research Council (MRC) grading system, angle of elbow flexion, and electromyography (EMG) were used to evaluate the recovery of elbow flexion at least 3 years postoperatively. The efficiency of motor function in the phrenic nerve transfer group was 83%, while it was 70% in the intercostal nerve transfer group. The two groups were not statistically different in terms of the MRC grade (p=0.646) and EMG results (p=0.646). The outstanding rates of angle of elbow flexion were 48% and 40% in the phrenic and intercostal nerve transfer groups, respectively. There was no significant difference of outstanding rates in the angle of elbow flexion between the two groups. Phrenic nerve transfer had a higher proportion of good prognosis for elbow flexion than intercostal nerve transfer, but the effective and outstanding rate had no significant difference for biceps reinnervation between the two groups according to MRC grading, angle of elbow flexion, and EMG. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Plantar-flexion of the ankle joint complex in terminal stance is initiated by subtalar plantar-flexion: A bi-planar fluoroscopy study.

    Science.gov (United States)

    Koo, Seungbum; Lee, Kyoung Min; Cha, Young Joo

    2015-10-01

    Gross motion of the ankle joint complex (AJC) is a summation of the ankle and subtalar joints. Although AJC kinematics have been widely used to evaluate the function of the AJC, the coordinated movements of the ankle and subtalar joints are not well understood. The purpose of this study was to accurately quantify the individual kinematics of the ankle and subtalar joints in the intact foot during ground walking by using a bi-planar fluoroscopic system. Bi-planar fluoroscopic images of the foot and ankle during walking and standing were acquired from 10 healthy subjects. The three-dimensional movements of the tibia, talus, and calcaneus were calculated with a three-dimensional/two-dimensional registration method. The skeletal kinematics were quantified from 9% to 86% of the full stance phase because of the limited camera speed of the X-ray system. At the beginning of terminal stance, plantar-flexion of the AJC was initiated in the subtalar joint on average at 75% ranging from 62% to 76% of the stance phase, and plantar-flexion of the ankle joint did not start until 86% of the stance phase. The earlier change to plantar-flexion in the AJC than the ankle joint due to the early plantar-flexion in the subtalar joint was observed in 8 of the 10 subjects. This phenomenon could be explained by the absence of direct muscle insertion on the talus. Preceding subtalar plantar-flexion could contribute to efficient and stable ankle plantar-flexion by locking the midtarsal joint, but this explanation needs further investigation. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Theseus Tail Being Unloaded

    Science.gov (United States)

    1996-01-01

    The tail of the Theseus prototype research aircraft is seen here being unloaded at NASA's Dryden Flight Research Center, Edwards, California, in May of 1996. The Theseus aircraft, built and operated by Aurora Flight Sciences Corporation, Manassas, Virginia, was a unique aircraft flown at NASA's Dryden Flight Research Center, Edwards, California, under a cooperative agreement between NASA and Aurora. Dryden hosted the Theseus program, providing hangar space and range safety for flight testing. Aurora Flight Sciences was responsible for the actual flight testing, vehicle flight safety, and operation of the aircraft. The Theseus remotely piloted aircraft flew its maiden flight on May 24, 1996, at Dryden. During its sixth flight on November 12, 1996, Theseus experienced an in-flight structural failure that resulted in the loss of the aircraft. As of the beginning of the year 2000, Aurora had not rebuilt the aircraft. Theseus was built for NASA under an innovative, $4.9 million fixed-price contract by Aurora Flight Sciences Corporation and its partners, West Virginia University, Morgantown, West Virginia, and Fairmont State College, Fairmont, West Virginia. The twin-engine, unpiloted vehicle had a 140-foot wingspan, and was constructed largely of composite materials. Powered by two 80-horsepower, turbocharged piston engines that drove twin 9-foot-diameter propellers, Theseus was designed to fly autonomously at high altitudes, with takeoff and landing under the active control of a ground-based pilot in a ground control station 'cockpit.' With the potential ability to carry 700 pounds of science instruments to altitudes above 60,000 feet for durations of greater than 24 hours, Theseus was intended to support research in areas such as stratospheric ozone depletion and the atmospheric effects of future high-speed civil transport aircraft engines. Instruments carried aboard Theseus also would be able to validate satellite-based global environmental change measurements

  15. Rehabilitation of uranium tailings impoundments

    International Nuclear Information System (INIS)

    Crawley, A.H.

    1983-01-01

    Under Australian environmental controls relating to the management of uranium tailings, it is no longer acceptable practice to search for a rehabilitation strategy at the end of production when the generation of tailings has ceased. The uranium projects currently in production and those being proposed are tightly regulated by the authorities. The waste management plans must consider site specific factors and must include selection of appropriate disposal sites and design for long term containment. The final encapsulation in engineered facilities must take into account the probable routes to the environment of the tailings. Rehabilitation shoud be undertaken by the mining and milling operators to standards approved by appropriate authorities. Appropriate administrative arrangements are required, by way of technical committees and financial bonds to ensure that agreed standards of rehabilitation may be achieved. Past and present experience with the rehabilitation of uranium tailings impoundments in Australia is discussed

  16. Sub-aerial tailings deposition

    International Nuclear Information System (INIS)

    Knight, R.B.; Haile, J.P.

    1984-01-01

    The sub-aerial technique involves the systematic deposition of tailings in thin layers and allowing each layer to settle, drain and partially air dry prior to covering with a further layer. Underdrainage produces densities in excess of those achieved by sub-aqueous deposition and any air-drying serves to preconsolidate each layer with a resulting further increase in density. The low permeability of the tailings surface resulting from this deposition technique results in high runoff coefficients and, by decanting the runoff component of direct precipitation, a net evaporation condition can be achieved even in high rainfall areas. An underdrainage system prevents the build-up of excess pore-pressures within the tailings mass and at decommissioning the tailings are fully consolidated and drained thereby eliminating the possibility of any long term seepage. This paper presents a general description of these design concepts, and details of two projects where the concepts have been applied

  17. Comparison of High-Flexion Fixed-Bearing and High-Flexion Mobile-Bearing Total Knee Arthroplasties-A Prospective Randomized Study.

    Science.gov (United States)

    Kim, Young-Hoo; Park, Jang-Won; Kim, Jun-Shik

    2018-01-01

    There is none, to our knowledge, about comparison of high-flexion fixed-bearing and high-flexion mobile-bearing total knee arthroplasties (TKAs) in the same patients. The purpose of this study was to determine whether clinical results; radiographic and computed tomographic scan results; and the survival rate of a high-flexion mobile-bearing TKA is better than that of a high-flexion fixed-bearing TKA. The present study consisted of 92 patients (184 knees) who underwent same-day bilateral TKA. Of those, 17 were men and 75 were women. The mean age at the time of index arthroplasty was 61.5 ± 8.3 years (range 52-65 years). The mean body mass index was 26.2 ± 3.3 kg/m 2 (range 23-34 kg/m 2 ). The mean follow-up was 11.2 years (range 10-12 years). The Knee Society knee scores (93 vs 92 points; P = .531) and function scores (80 vs 80 points; P = 1.000), WOMAC scores (14 vs 15 points; P = .972), and UCLA activity scores (6 vs 6 points; P = 1.000) were not different between the 2 groups at 12 years follow-up. There were no differences in any radiographic and CT scan parameters between the 2 groups. Kaplan-Meier survivorship of the TKA component was 98% (95% confidence interval, 93-100) in the high-flexion fixed-bearing TKA group and 99% (95% confidence interval, 94-100) in the high-flexion mobile-bearing TKA group 12 years after the operation. We found no benefit to mobile-bearing TKA in terms of pain, function, radiographic and CT scan results, and survivorship. Longer-term follow-up is necessary to prove the benefit of the high-flexion mobile-bearing TKA over the high-flexion fixed-bearing TKA. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Sirenomelia apus with vestigial tail.

    Science.gov (United States)

    Parikh, Tushar B; Nanavati, Ruchi N; Udani, Rekha H

    2005-04-01

    Sirenomelia is an exceptionally rare congenital malformation characterized by complete or near complete fusion of lower limbs. A newborn with clinical features of sirenomelia including fused lower limbs in medial position, absent fibula, anal atresia, complete absence of urogenital system (bilateral renal agenesis, absent ureters, urinary bladder, absent internal and external genitalia), a single umbilical artery and a vestigial tail is reported. Association of vestigial tail with sirenomelia is not described in the literature.

  19. The range of excursion of flexor tendons in Zone V: a comparison of active vs passive flexion mobilisation regimes.

    LENUS (Irish Health Repository)

    Panchal, J

    1997-10-01

    A number of early postoperative mobilisation regimes have been developed in an attempt to increase tendon excursion and gliding and thereby reduce formation of adhesions following repair of flexor tendons. Early active flexion mobilisation regimes are becoming more popular, and have replaced early passive flexion regimes in many centres. The aim of the present study was: (a) to determine the range of excursion of flexor tendons in Zone V, and (b) to compare the excursion ranges between active (Belfast) and passive (modified Duran) flexion mobilisation regimes postoperatively. This was done (a) in two cadavers, and (b) in two patients intraoperatively, and postoperatively at 10 days, 3 weeks and 6 weeks. With passive flexion, the mean tendon excursion in Zone V in cadavers was 1 mm for flexor digitorum superficialis (FDS), flexor digitorum profundus (FDP) and flexor pollicis longus (FPL) tendons respectively. With simulated active flexion, the mean tendon excursion was 14 mm, 10 mm and 11 mm respectively. The mean tendon excursion in clinical cases intraoperatively following passive flexion was 2 mm for FDS, FDP and FPL respectively; following simulated active flexion it was 10 mm, 11 mm and 11 mm for FDS, FDP and FPL respectively. On the tenth day following repair, the mean excursions of FDS, FDP and FPL were 1 mm, 4 mm and 4 mm on passive flexion as compared to 3 mm, 10 mm and 12 mm on active flexion respectively. Three weeks postoperatively, the mean excursions of FDS, FDP and FPL tendons were 1 mm, 2 mm and 1 mm on passive flexion as compared to 5 mm, 15 mm on active flexion respectively. Six weeks postoperatively, the mean excursions of FDS, FDP and FPL tendons were 9 mm, 7 mm and 4 mm on passive flexion as compared to 12 mm, 33 mm and 20 mm on active flexion respectively. These results demonstrate an increased excursion of repaired flexor tendons in Zone V following an active flexion mobilisation regime as compared to a passive flexion mobilisation regime.

  20. Multichannel thickener of flotation tailings

    Energy Technology Data Exchange (ETDEWEB)

    Kondratenko, A F; Shuliko, A N; Zinchenko, A F

    1983-04-01

    A multichannel thickener of flotation tailings developed by Ukrniiugleobogashchenie is described. Tailings with solid content ranging from 40 to 60 g/l are mixed with flocculation reagents (quantity ratio from 60 to 70 g/l) in a turbulent mixer: waste water with tailings fed to the mixer is divided into three streams, flocculation reagents are batched in stages with each water stream. After turbulent mixing, water, tailings and reagent are fed to the settling chamber. Settling chamber (dimensions 2.4 x 1.5 x 1.0 m) is divided into a number of channels by settling surfaces of 0.35 m/sup 2/ each, inclined at an angle of 55 degrees. Distance between the surfaces is 50 mm. The thickener has a total settling surface of 18.7 m/sup 2/. Water with tailings flows upwards, cleaned water is removed by a separating system and settled tailings move downward and accumulate in the compacting chamber (dimensions 1.5 x 1.5 x 0.9 m). From the compacting chamber thickened slurry with solid content from 90 to 150 g/l is removed by a hydraulic system. During performance testing in some plants preparing coal difficult to wash, thickening efficiency amounted to 100%. The results of performance testing are shown in two tables. Factors which influence thickener productivity are evaluated. (In Russian)

  1. Turtle Flexion Reflex Motor Patterns Show Windup, Mediated Partly by L-type Calcium Channels

    Directory of Open Access Journals (Sweden)

    Keith P. Johnson

    2017-10-01

    Full Text Available Windup is a form of multisecond temporal summation in which identical stimuli, delivered seconds apart, trigger increasingly strong neuronal responses. L-type Ca2+ channels have been shown to play an important role in the production of windup of spinal cord neuronal responses, initially in studies of turtle spinal cord and later in studies of mammalian spinal cord. L-type Ca2+ channels have also been shown to contribute to windup of limb withdrawal reflex (flexion reflex in rats, but flexion reflex windup has not previously been described in turtles and its cellular mechanisms have not been studied. We studied windup of flexion reflex motor patterns, evoked with weak mechanical and electrical stimulation of the dorsal hindlimb foot skin and assessed via a hip flexor (HF nerve recording, in spinal cord-transected and immobilized turtles in vivo. We found that an L-type Ca2+ channel antagonist, nifedipine, applied at concentrations of 50 μM or 100 μM to the hindlimb enlargement spinal cord, significantly reduced windup of flexion reflex motor patterns, while lower concentrations of nifedipine had no such effect. Nifedipine similarly reduced the amplitude of an individual flexion reflex motor pattern evoked by a stronger mechanical stimulus, in a dose-dependent manner, suggesting that L-type Ca2+ channels contribute to each flexion reflex as well as to multisecond summation of flexion reflex responses in turtles. We also found that we could elicit flexion reflex windup consistently using a 4-g von Frey filament, which is not usually considered a nociceptive stimulus. Thus, it may be that windup can be evoked by a wide range of tactile stimuli and that L-type calcium channels contribute to multisecond temporal summation of diverse tactile stimuli across vertebrates.

  2. Modelling knee flexion effects on joint power absorption and adduction moment.

    Science.gov (United States)

    Nagano, Hanatsu; Tatsumi, Ichiroh; Sarashina, Eri; Sparrow, W A; Begg, Rezaul K

    2015-12-01

    Knee osteoarthritis is commonly associated with ageing and long-term walking. In this study the effects of flexing motions on knee kinetics during stance were simulated. Extended knees do not facilitate efficient loading. It was therefore, hypothesised that knee flexion would promote power absorption and negative work, while possibly reducing knee adduction moment. Three-dimensional (3D) position and ground reaction forces were collected from the right lower limb stance phase of one healthy young male subject. 3D position was sampled at 100 Hz using three Optotrak Certus (Northern Digital Inc.) motion analysis camera units, set up around an eight metre walkway. Force plates (AMTI) recorded ground reaction forces for inverse dynamics calculations. The Visual 3D (C-motion) 'Landmark' function was used to change knee joint positions to simulate three knee flexion angles during static standing. Effects of the flexion angles on joint kinetics during the stance phase were then modelled. The static modelling showed that each 2.7° increment in knee flexion angle produced 2.74°-2.76° increments in knee flexion during stance. Increased peak extension moment was 6.61 Nm per 2.7° of increased knee flexion. Knee flexion enhanced peak power absorption and negative work, while decreasing adduction moment. Excessive knee extension impairs quadriceps' power absorption and reduces eccentric muscle activity, potentially leading to knee osteoarthritis. A more flexed knee is accompanied by reduced adduction moment. Research is required to determine the optimum knee flexion to prevent further damage to knee-joint structures affected by osteoarthritis. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. COMPARATIVE BIOMECHANICAL ANALYSES OF SQUAT JUMP WITHOUT AND WITH FLEXION IN KNEE JOINT

    Directory of Open Access Journals (Sweden)

    Saša Bubanj

    2009-11-01

    Full Text Available In sports hall of Faculty of sports and physical education in Niš, student demon- strated technique of squat jump – without and with flexion in knee joint. Elements of technique were recorded by using one digital video camera in sagital plane. By using comparative kinematics analyses, there were establish differences in values of kinema- tics parametres of different body segments. Bigger elevation of body centre of gravity was ascertain at bounce without flexion in knee joint.

  4. Guidelines for cleanup of uranium tailings from inactive mills

    International Nuclear Information System (INIS)

    Goldsmith, W.A.; Haywood, F.F.; Jacobs, D.G.

    1975-01-01

    Recent experiences in Grand Junction, Colorado, have indicated the significance of uranium tailings as sources of nonoccupational exposure and suggest that current methods for perpetual care and isolation of the large areas covered by tailings piles at inactive mill locations may be inadequate for minimizing human exposure. This paper presents the rationale and the procedures used in reviewing the adequacy of proposed criteria for remedial action at these sites. Exposures due to aquatic, terrestrial, airborne, and direct contamination pathways were compared to determine the most important radionuclides in the pile and their pathways to man. It is shown that the most hazardous components of the tailings are 226 Ra and 230 Th. The long half-lives of these radionuclides require the consideration of continuous occupancy of the vacated site at some future time, even if the immediately projected land use does not anticipate maximum exposure

  5. Isokinetic profile of elbow flexion and extension strength in elite junior tennis players.

    Science.gov (United States)

    Ellenbecker, Todd S; Roetert, E Paul

    2003-02-01

    Descriptive study. To determine whether bilateral differences exist in concentric elbow flexion and extension strength in elite junior tennis players. The repetitive nature of tennis frequently produces upper extremity overuse injuries. Prior research has identified tennis-specific strength adaptation in the dominant shoulder and distal upper extremity musculature of elite players. No previous study has addressed elbow flexion and extension strength. Thirty-eight elite junior tennis players were bilaterally tested for concentric elbow flexion and extension muscle performance on a Cybex 6000 isokinetic dynamometer at 90 degrees/s, 210 degrees/s, and 300 degrees/s. Repeated-measures ANOVAs were used to test for differences between extremities, muscle groups, and speed. Significantly greater (Pelbow extension peak torque values were measured at 90 degrees/s, 210 degrees/s, and 300 degrees/s for males. Significantly greater (Pelbow flexion muscular performance in males and for elbow flexion or extension peak torque and single-repetition work values in females. No significant difference between extremities was measured in elbow flexion/extension strength ratios in females and significant differences between extremities in this ratio were only present at 210 degrees/s in males (Pelbow in male elite junior tennis players but not females. These data have ramifications for clinicians rehabilitating upper extremity injuries in patients from this population.

  6. Experimental measurement of flexion-extension movement in normal and corpse prosthetic elbow joint.

    Science.gov (United States)

    TarniŢă, Daniela; TarniŢă, DănuŢ Nicolae

    2016-01-01

    This paper presents a comparative experimental study of flexion-extension movement in healthy elbow and in the prosthetic elbow joint fixed on an original experimental bench. Measurements were carried out in order to validate the functional morphology and a new elbow prosthesis type ball head. The three-dimensional (3D) model and the physical prototype of our experimental bench used to test elbow endoprosthesis at flexion-extension and pronation-supination movements is presented. The measurements were carried out on a group of nine healthy subjects and on the prosthetic corpse elbow, the experimental data being obtained for flexion-extension movement cycles. Experimental data for the two different flexion-extension tests for the nine subjects and for the corpse prosthetic elbow were acquired using SimiMotion video system. Experimental data were processed statistically. The corresponding graphs were obtained for all subjects in the experimental group, and for corpse prosthetic elbow for both flexion-extension tests. The statistical analysis has proved that the flexion angles of healthy elbows were significantly close to the values measured at the prosthetic elbow fixed on the experimental bench. The studied elbow prosthesis manages to re-establish the mobility for the elbow joint as close to the normal one.

  7. CT of the pancreatic body and tail in cancer of the head

    International Nuclear Information System (INIS)

    Ono, Minoru; Muranaka, Tooru; Nishitani, Hiromu; Onitsuka, Hideo; Kawanami, Takashi; Matsuura, Keiichi

    1983-01-01

    In comparison with chronic pancreatitis (27 cases), CT images of secondary changes in the pancreatic body and tail in cancer of the pancreatic head were studied in 17 cases. In cancer cases, the pancreatic duct was dilated in a rosary or linear form, and a fairly large portion of the duct was visualized in continuation in one slice. The parenchyma was uniformly atrophic. Chronic pancreatitis demonstrated various CT images. In the localized-mass-forming type, the pancreatic body and tail showed findings similar to those of cancer in some cases, but unevenness of the pancreatic parenchyma and flexion, tortuosity and discontinuity of the pancreatic duct were observed only in chronic pancreatitis. As well as improvement in CT images, the spatial relationship between the pancreatic duct and parenchyma should be studied in more detail. (Chiba, N.)

  8. Presentations of the CONRAD tailings seminar : exploring the past, present and future of tailings technologies

    International Nuclear Information System (INIS)

    2004-01-01

    This symposium explored oil sand tailings activities in Canada and their associated technologies. It was attended by active and prospective tailings researchers and developers of tailings technology who addressed timely issues regarding mature fine tailings, consolidated tailings, thickened tailings, and emerging tailings technologies. The collaborative research projects that are underway at the Oil Sands Tailings Research Facility were also discussed along with other topics such as tailings ponds management, water treatment, water quality and water supply security. All 16 presentations featured at this conference were indexed separately for inclusion in this database

  9. More tail lesions among undocked than tail docked pigs in a conventional herd

    DEFF Research Database (Denmark)

    Lahrmann, H. P.; Busch, M. E.; D'Eath, R. B.

    2017-01-01

    The vast majority of piglets reared in the European Union (EU) and worldwide is tail docked to reduce the risk of being tail bitten, even though EU animal welfare legislation bans routine tail docking. Many conventional herds experience low levels of tail biting among tail docked pigs, however...

  10. Research on Long Tail Recommendation Algorithm

    Science.gov (United States)

    Hu, Xuezhi; Zhang, Chuang; Wu, Ming; Zeng, Yang

    2017-10-01

    Most recommendation systems in the major electronic commerce platforms are influenced by the long tail effect more or less. There are sufficient researches of how to assess recommendation effect while no criteria to evaluate long tail recommendation rate. In this study, we first discussed the existing problems of recommending long tail products through specific experiments. Then we proposed a long tail evaluation criteria and compared the performance in long tail recommendation between different models.

  11. Plant growth-promoting bacteria for phytostabilization of mine tailings.

    Science.gov (United States)

    Grandlic, Christopher J; Mendez, Monica O; Chorover, Jon; Machado, Blenda; Maier, Raina M

    2008-03-15

    Eolian dispersion of mine tailings in arid and semiarid environments is an emerging global issue for which economical remediation alternatives are needed. Phytostabilization, the revegetation of these sites with native plants, is one such alternative. Revegetation often requires the addition of bulky amendments such as compost which greatly increases cost. We report the use of plant growth-promoting bacteria (PGPB) to enhance the revegetation of mine tailings and minimize the need for compost amendment. Twenty promising PGPB isolates were used as seed inoculants in a series of greenhouse studies to examine revegetation of an extremely acidic, high metal contenttailings sample previously shown to require 15% compost amendment for normal plant growth. Several isolates significantly enhanced growth of two native species, quailbush and buffalo grass, in tailings. In this study, PGPB/compost outcomes were plant specific; for quailbush, PGPB were most effective in combination with 10% compost addition while for buffalo grass, PGPB enhanced growth in the complete absence of compost. Results indicate that selected PGPB can improve plant establishment and reduce the need for compost amendment. Further, PGPB activities necessary for aiding plant growth in mine tailings likely include tolerance to acidic pH and metals.

  12. Neuromuscular Activation of the Vastus Intermedius Muscle during Isometric Hip Flexion.

    Directory of Open Access Journals (Sweden)

    Akira Saito

    Full Text Available Although activity of the rectus femoris (RF differs from that of the other synergists in quadriceps femoris muscle group during physical activities in humans, it has been suggested that the activation pattern of the vastus intermedius (VI is similar to that of the RF. The purpose of present study was to examine activation of the VI during isometric hip flexion. Ten healthy men performed isometric hip flexion contractions at 25%, 50%, 75%, and 100% of maximal voluntary contraction at hip joint angles of 90°, 110° and 130°. Surface electromyography (EMG was used to record activity of the four quadriceps femoris muscles and EMG signals were root mean square processed and normalized to EMG amplitude during an isometric knee extension with maximal voluntary contraction. The normalized EMG was significantly higher for the VI than for the vastus medialis during hip flexion at 100% of maximal voluntary contraction at hip joint angles of 110° and 130° (P < 0.05. The onset of VI activation was 230-240 ms later than the onset of RF activation during hip flexion at each hip joint angle, which was significantly later than during knee extension at 100% of maximal voluntary contraction (P < 0.05. These results suggest that the VI is activated later than the RF during hip flexion. Activity of the VI during hip flexion might contribute to stabilize the knee joint as an antagonist and might help to smooth knee joint motion, such as in the transition from hip flexion to knee extension during walking, running and pedaling.

  13. Dewatering tailings impoundments : interior drains

    International Nuclear Information System (INIS)

    Charlie, W.A.; Doehring, D.O.; Durnford, D.S.

    1984-01-01

    For the design of a new uranium tailings impoundment in the western United States, it was proposed that an interior drainage system be considered to economically and reliably minimize potential short- and long-term environmental impacts. The objectives were to decrease the effective hydraulic head on the clay liner, to dewater and stabilize the tailings, and to increase the amount of water recycled to the mill. In addition, desaturation of the impoundment would induce capillary pressure (negative porewater pressure), further reducing the potential movement of dissolved pollutants. This paper presents saturated and unsaturated seepage principles and reviews the concept, criteria and design of the various interior drainage systems considered

  14. Constraining primordial non-Gaussianity with cosmological weak lensing: shear and flexion

    International Nuclear Information System (INIS)

    Fedeli, C.; Bartelmann, M.; Moscardini, L.

    2012-01-01

    We examine the cosmological constraining power of future large-scale weak lensing surveys on the model of the ESA planned mission Euclid, with particular reference to primordial non-Gaussianity. Our analysis considers several different estimators of the projected matter power spectrum, based on both shear and flexion. We review the covariance and Fisher matrix for cosmic shear and evaluate those for cosmic flexion and for the cross-correlation between the two. The bounds provided by cosmic shear alone are looser than previously estimated, mainly due to the reduced sky coverage and background number density of sources for the latest Euclid specifications. New constraints for the local bispectrum shape, marginalized over σ 8 , are at the level of Δf NL ∼ 100, with the precise value depending on the exact multipole range that is considered in the analysis. We consider three additional bispectrum shapes, for which the cosmic shear constraints range from Δf NL ∼ 340 (equilateral shape) up to Δf NL ∼ 500 (orthogonal shape). Also, constraints on the level of non-Gaussianity and on the amplitude of the matter power spectrum σ 8 are almost perfectly anti-correlated, except for the orthogonal bispectrum shape for which they are correlated. The competitiveness of cosmic flexion constraints against cosmic shear ones depends by and large on the galaxy intrinsic flexion noise, that is still virtually unconstrained. Adopting the very high value that has been occasionally used in the literature results in the flexion contribution being basically negligible with respect to the shear one, and for realistic configurations the former does not improve significantly the constraining power of the latter. Since the shear shot noise is white, while the flexion one decreases with decreasing scale, by considering high enough multipoles the two contributions have to become comparable. Extending the analysis up to l max = 20,000 cosmic flexion, while being still subdominant

  15. Biceps brachii long head overactivity associated with elbow flexion contracture in brachial plexus birth palsy.

    Science.gov (United States)

    Sheffler, Lindsey C; Lattanza, Lisa; Sison-Williamson, Mitell; James, Michelle A

    2012-02-15

    The etiology of elbow flexion contracture in children with brachial plexus birth palsy remains unclear. We hypothesized that the long head of the biceps brachii muscle assists with shoulder stabilization in children with brachial plexus birth palsy and that overactivity of the long head during elbow and shoulder activity is associated with an elbow flexion contracture. Twenty-one patients with brachial plexus birth palsy-associated elbow flexion contracture underwent testing with surface electromyography. Twelve patients underwent repeat testing with fine-wire electromyography. Surface electrodes were placed on the muscle belly, and fine-wire electrodes were inserted bilaterally into the long and short heads of the biceps brachii. Patients were asked to perform four upper extremity tasks: elbow flexion-extension, hand to head, high reach, and overhead ball throw. The mean duration of muscle activity in the affected limb was compared with that in the contralateral, unaffected limb, which was used as a control. Three-dimensional motion analysis, surface dynamometry, and validated function measures were used to evaluate upper extremity kinematics, elbow flexor-extensor muscle imbalance, and function. The mean activity duration of the long head of the biceps brachii muscle was significantly higher in the affected limb as compared with the contralateral, unaffected limb during hand-to-head tasks (p = 0.02) and high-reach tasks (p = 0.03). No significant differences in mean activity duration were observed for the short head of the biceps brachii muscle between the affected and unaffected limbs. Isometric strength of elbow flexion was not significantly higher than that of elbow extension in the affected limb (p = 0.11). Overactivity of the long head of the biceps brachii muscle is associated with and may contribute to the development of elbow flexion contracture in children with brachial plexus birth palsy. Elbow flexion contracture may not be associated with an elbow

  16. Constraining primordial non-Gaussianity with cosmological weak lensing: shear and flexion

    Energy Technology Data Exchange (ETDEWEB)

    Fedeli, C. [Department of Astronomy, University of Florida, 211 Bryant Space Science Center, Gainesville, FL 32611-2055 (United States); Bartelmann, M. [Zentrum für Astronomie, Universität Heidelberg, Albert-Überle-Straße 2, 69120 Heidelberg (Germany); Moscardini, L., E-mail: cosimo.fedeli@astro.ufl.edu, E-mail: bartelmann@uni-heidelberg.de, E-mail: lauro.moscardini@unibo.it [Dipartimento di Astronomia, Università di Bologna, Via Ranzani 1, 40127 Bologna (Italy)

    2012-10-01

    We examine the cosmological constraining power of future large-scale weak lensing surveys on the model of the ESA planned mission Euclid, with particular reference to primordial non-Gaussianity. Our analysis considers several different estimators of the projected matter power spectrum, based on both shear and flexion. We review the covariance and Fisher matrix for cosmic shear and evaluate those for cosmic flexion and for the cross-correlation between the two. The bounds provided by cosmic shear alone are looser than previously estimated, mainly due to the reduced sky coverage and background number density of sources for the latest Euclid specifications. New constraints for the local bispectrum shape, marginalized over σ{sub 8}, are at the level of Δf{sub NL} ∼ 100, with the precise value depending on the exact multipole range that is considered in the analysis. We consider three additional bispectrum shapes, for which the cosmic shear constraints range from Δf{sub NL} ∼ 340 (equilateral shape) up to Δf{sub NL} ∼ 500 (orthogonal shape). Also, constraints on the level of non-Gaussianity and on the amplitude of the matter power spectrum σ{sub 8} are almost perfectly anti-correlated, except for the orthogonal bispectrum shape for which they are correlated. The competitiveness of cosmic flexion constraints against cosmic shear ones depends by and large on the galaxy intrinsic flexion noise, that is still virtually unconstrained. Adopting the very high value that has been occasionally used in the literature results in the flexion contribution being basically negligible with respect to the shear one, and for realistic configurations the former does not improve significantly the constraining power of the latter. Since the shear shot noise is white, while the flexion one decreases with decreasing scale, by considering high enough multipoles the two contributions have to become comparable. Extending the analysis up to l{sub max} = 20,000 cosmic flexion, while

  17. Predicting radon flux from uranium mill tailings

    International Nuclear Information System (INIS)

    Freeman, H.D.; Hartley, J.N.

    1983-11-01

    Pacific Northwest Laboratory (PNL), under contract to the US Department of Energy (DOE) Uranium Mill Tailings Remedial Action Project (UMTRAP) office, is developing technology for the design of radon barriers for uranium mill tailings piles. To properly design a radon cover for a particular tailings pile, the radon flux emanating from the bare tailings must be known. The tailings characteristics required to calculate the radon flux include radium-226 content, emanating power, bulk density, and radon diffusivity. This paper presents theoretical and practical aspects of estimating the radon flux from an uranium tailings pile. Results of field measurements to verify the calculation methodology are also discussed. 24 references, 4 figures, 4 tables

  18. Serial casting for elbow flexion contractures in neonatal brachial plexus palsy.

    Science.gov (United States)

    Duijnisveld, B J; Steenbeek, D; Nelissen, R G H H

    2016-09-02

    The objective of this study was to evaluate the effectiveness of serial casting of elbow flexion contractures in neonatal brachial plexus palsy. A prospective consecutive cohort study was performed with a median follow-up of 5 years. Forty-one patients with elbow flexion contractures ≥ 30° were treated with serial casting until the contracture was ≤ 10°, for a maximum of 8 weeks. Range of motion, number of recurrences and patient satisfaction were recorded and analyzed using Wilcoxon signed-rank and Cox regression tests. Passive extension increased from a median of -40° (IQR -50 to -30) to -15° (IQR -10 to -20, p casting had to be prematurely replaced by night splinting due to complaints. Serial casting improved elbow flexion contractures, although recurrences were frequent. The severity of elbow flexion contracture is a predictor of recurrence. We recommend more research on muscle degeneration and determinants involved in elbow flexion contractures to improve treatment strategies and prevent side-effects.

  19. ARTHROMETRIC EVALUATION OF STABILIZING EFFECT OF KNEE FUNCTIONAL BRACING AT DIFFERENT FLEXION ANGLES

    Directory of Open Access Journals (Sweden)

    Saeedeh Seyed Mohseni

    2009-06-01

    Full Text Available Previous in-vivo investigations on the stabilizing efficacy of knee bracing for ACL reconstructed patients have been often limited to 20-30 degrees of knee flexion. In this study, the effectiveness of a uniaxial hinged functional brace to improve the knee stability was assessed at 30, 60 and 90 degrees of knee flexion. Arthrometry tests were conducted on 15 healthy subjects before and following wearing the brace and the tibial displacements were measured at up to 150 N anterior forces. Results indicated that functional bracing has a significant stabilizing effect throughout the range of knee flexion examined (p < 0.05. The rate of effectiveness, however, was not consistent across the flexion range, e.g., 50% at 30 degrees and only 4% at 90 degrees. It was suggested that accurate sizing and fitting as well as attention to correct hinge placement relative to the femoral condyles can limit brace migration and improve its effectiveness in mid and deep knee flexion. With using adaptive limb fittings, through flexible pads, and a polycentric joint a more significant improvement of the overall brace performance and efficacy might be obtained

  20. MR imaging of the knee extension and flexion. Diagnostic value for reconstructed anterior cruciate ligament

    Energy Technology Data Exchange (ETDEWEB)

    Niitsu, Mamoru; Ikeda, Kotaroh; Fukubayashi, Tohru [Tsukuba Univ., Ibaraki (Japan). Inst. of Clinical Medicine] [and others

    1995-09-01

    The purpose of this study is to determine the value of extended and flexed knee positions in MR imaging of the surgically reconstructed anterior cruciate ligament (ACL). With a mobile knee brace and a flexible surface coil, knee joint was enabled to extend to a full-extension and bend vertically to a semi-flexion (average 45deg of flexion) within the confines of the magnet bore. Sets of 3-mm-thick oblique sagittal proton-weighted turbo spin echo MR images were obtained at both extended and flexed positions. Twenty-five knees with intact ACL grafts and three knees with arthroscopically proved graft tears were evaluated. Compared to the extended position, MR images of flexed knee provided better delineation of the intact and complicated ACL grafts with statistical significance. The intact graft appeared relaxed at the semi-flexion and taut at the extension. Overall lengths of the intact grafts were readily identified at the flexion. Stretched along the intercondylar roof, the grafts were poorly outlined at the extension. MR images with knee flexion delineated the disrupted site from the impingement more clearly than that with knee extension. (author).

  1. Extension and flexion in the upper cervical spine in neck pain patients.

    Science.gov (United States)

    Ernst, Markus J; Crawford, Rebecca J; Schelldorfer, Sarah; Rausch-Osthoff, Anne-Kathrin; Barbero, Marco; Kool, Jan; Bauer, Christoph M

    2015-08-01

    Neck pain is a common problem in the general population with high risk of ongoing complaints or relapses. Range of motion (ROM) assessment is scientifically established in the clinical process of diagnosis, prognosis and outcome evaluation in neck pain. Anatomically, the cervical spine (CS) has been considered in two regions, the upper and lower CS. Disorders like cervicogenic headache have been clinically associated with dysfunctions of the upper CS (UCS), yet ROM tests and measurements are typically conducted on the whole CS. A cross-sectional study assessing 19 subjects with non-specific neck pain was undertaken to examine UCS extension-flexion ROM in relation to self-reported disability and pain (via the Neck Disability Index (NDI)). Two measurement devices (goniometer and electromagnetic tracking) were employed and compared. Correlations between ROM and the NDI were stronger for the UCS compared to the CS, with the strongest correlation between UCS flexion and the NDI-headache (r = -0.62). Correlations between UCS and CS ROM were fair to moderate, with the strongest correlation between UCS flexion and CS extension ROM (r = -0.49). UCS flexion restriction is related to headache frequency and intensity. Consistency and agreement between both measurement systems and for all tests was high. The results demonstrate that separate UCS ROM assessments for extension and flexion are useful in patients with neck pain. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Ruin problems and tail asymptotics

    DEFF Research Database (Denmark)

    Rønn-Nielsen, Anders

    The thesis Ruin Problems and Tail Asymptotics provides results on ruin problems for several classes of Markov processes. For a class of diffusion processes with jumps an explicit expression for the joint Laplace transform of the first passage time and the corresponding undershoot is derived...

  3. Liner used in tailings ponds

    International Nuclear Information System (INIS)

    Dinchak, W.G.

    1984-01-01

    A composite liner has been developed for use in hazardous waste impoundments and in tailings ponds where uranium is involved. The liner offers a high degree of reliability against seepage, is durable, and provides a firm working surface. The advantages of the liner are discussed

  4. Portfolio selection with heavy tails

    NARCIS (Netherlands)

    Hyung, N.; Vries, de C.G.

    2007-01-01

    Consider the portfolio problem of choosing the mix between stocks and bonds under a downside risk constraint. Typically stock returns exhibit fatter tails than bonds corresponding to their greater downside risk. Downside risk criteria like the safety first criterion therefore often select corner

  5. Portfolio Selection with Heavy Tails

    NARCIS (Netherlands)

    N. Hyung (Namwon); C.G. de Vries (Casper)

    2004-01-01

    textabstractConsider the portfolio problem of choosing the mix between stocks and bonds under a downside risk constraint. Typically stock returns exhibit fatter tails than bonds corresponding to their greater downside risk. Downside risk criteria like the safety first criterion therefore of ten

  6. Tails, Fears and Risk Premia

    DEFF Research Database (Denmark)

    Bollerslev, Tim; Todorov, Victor

    solely be explained by the level of the volatil- ity. Our empirical investigations are essentially model-free. We estimate the expected values of the tails under the statistical probability measure from "medium" size jumps in high-frequency intraday prices and an extreme value theory approximation...

  7. Capital regulation and tail risk

    NARCIS (Netherlands)

    Perotti, E.; Ratnovski, L.; Vlahu, R.

    2011-01-01

    The paper studies risk mitigation associated with capital regulation, in a context when banks may choose tail risk assets. We show that this undermines the traditional result that higher capital reduces excess risk-taking driven by limited liability. When capital raising is costly, poorly

  8. Capital regulation and tail risk

    NARCIS (Netherlands)

    Perotti, E.; Ratnovski, L.; Vlahu, R.

    2011-01-01

    The paper studies risk mitigation associated with capital regulation, in a context where banks may choose tail risk assets. We show that this undermines the traditional result that higher capital reduces excess risk taking driven by limited liability. Moreover, higher capital may have an unintended

  9. DLM for T-Tails

    CSIR Research Space (South Africa)

    Van Zyl, Lourens H

    2007-06-01

    Full Text Available This paper describes the extension of the DLM to account for effects that are critical to the modelling of T-tail flutter. The boundary condition is made more general to account for yaw/dihedral and sideslip/dihedral coupling and the calculation...

  10. UTAP, U Tailings Assessment Program

    International Nuclear Information System (INIS)

    Holmes, Ron

    1998-01-01

    1 - Description of program or function: UTAP carries out probabilistic analyses of the behaviour and environmental effects of uranium mill tailings, following close-out of milling operations. The models have been designed to allow predictions to be made for distances up to 50 kilometers in all directions from the tailings area. The models include features which include the ability to incorporate different receptors and site characteristics and to deal with input parameters which vary with time. 2 - Method of solution: UTAP is composed of a number of modules. These may be classified as either component or control modules. Component modules (or models) are the programs directly concerned with the simulation of a uranium tailings physical system; that is the computer implementation of the mathematical models representing the uranium tailings pile and surrounding environment. Control modules provide the infrastructure for probabilistic analysis using the component modules. These functions include probabilistic sampling of input parameters such as constant, normal, log-normal, uniform, log-uniform, triangular, Weibull, Beta, arbitrary and correlated. The sampling method used is straight Monte Carlo. The radionuclides modelled are: natural uranium, total thorium, radium-226, radon-222 and lead-210. The pH of the reference uranium tailings site and a chained river-lake system are also modelled. For the afore- mentioned radionuclides the following pathways of dose to the receptors modelled: water consumption, fish consumption, radon inhalation, dust inhalation, vegetable consumption, animal produce consumption and ground-shine. 3 - Restrictions on the complexity of the problem: The maximum number of steps through time allowed is 300

  11. Long-term stabilization of uranium mill tailings

    International Nuclear Information System (INIS)

    Voorhees, L.D.; Sale, M.J.; Webb, J.W.; Mulholland, P.J.

    1984-01-01

    The primary hazard associated with uranium mill tailings is exposure to a radioactive gas, radon-222, the concentration of which has been correlated with the occurrence of lung cancer. Previous studies on radon attenuation conclude that the placement of earthen cover materials over the tailings is the most effective technique for reducing radioactive emissions and dispersal of tailings. The success of such a plan, however, is dependent on ensuring the long-term integrity of these cover materials. Soil erosion from water and wind is the major natural cause of destabilizing earthen cover materials. Field data related to the control of soil loss are limited and only indirectly apply to the problem of isolation of uranium mill tailings over very long time periods (up to 80,000 a). However, sufficient information is available to determine benefits that will result from changes in specific design variables and to evaluate the need for different design strategies among potential disposal sites. The three major options available for stabilization of uranium mill tailings are (1) rock cover, (2) soil and revegetation, or (3) a combination of both on different portions of the tailings cover. The optimal choice among these alternatives depends on site-specific characteristics such as climate and local geomorphology and soils, and on design variables such as embankment heights and slopes, modification of upstream drainage, and revegetation practices. Generally, geomorphic evidence suggests that use of soil and vegetation alone will not be adequate to reduce erosion on slopes greater than about 5 to 9%. For these steeper slopes, the use of rock talus or riprap will be necessary to maximize the probability of long-term stability. The use of vegetation to control erosion on the flatter portions of the site may be practicable in regions of the USA with sufficient rainfall and suitable soil types, but revegetation practices must be carefully evaluated to ensure that long

  12. The Immediate Effect of Neuromuscular Joint Facilitation (NJF) Treatment on Electromechanical Reaction Times of Hip Flexion.

    Science.gov (United States)

    Huo, Ming; Wang, Hongzhao; Ge, Meng; Huang, Qiuchen; Li, Desheng; Maruyama, Hitoshi

    2013-11-01

    [Purpose] The aim of this study was to investigate the change in electromechanical reaction times (EMG-RT) of hip flexion of younger persons after neuromuscular joint facilitation (NJF) treatment. [Subjects] The subjects were 39 healthy young people, who were divided into two groups: a NJF group and a proprioceptive neuromuscular facilitation (PNF) group. The NJF group consisted of 16 subjects (7 males, 9 females), and the PNF group consisted of 23 subjects (10 males, 13 females). [Methods] Participants in the NJF group received NJF treatment. We measured the EMG-RT, the premotor time (PMT) and the motor time (MT) during hip flexion movement before and after the intervention in both groups. [Results] There were no significant differences among the results of the PNF group. For the NJF group, there were significant differences in PMT and EMG-RT after NJF treatment. [Conclusion] These results suggest that there is an immediate effect of NJF intervention on electromechanical reaction times of hip flexion.

  13. Flexion synergy overshadows flexor spasticity during reaching in chronic moderate to severe hemiparetic stroke.

    Science.gov (United States)

    Ellis, Michael D; Schut, Ingrid; Dewald, Julius P A

    2017-07-01

    Pharmaceutical intervention targets arm flexor spasticity with an often-unsuccessful goal of improving function. Flexion synergy is a related motor impairment that may be inadvertently neglected. Here, flexor spasticity and flexion synergy are disentangled to determine their contributions to reaching dysfunction. Twenty-six individuals participated. A robotic device systematically modulated shoulder abduction loading during ballistic reaching. Elbow muscle electromyography data were partitioned into windows delineated by elbow joint velocity allowing for the separation of synergy- and spasticity-related activation. Reaching velocity decreased with abduction loading (psynergy increased with abduction loading (psynergy is the predominant contributor to reaching dysfunction while flexor spasticity appears only relevant during unnaturally occurring passively supported movement. Interventions targeting flexion synergy should be leveraged in future stroke recovery trials. Copyright © 2017 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

  14. Modelling and Analysis on Biomechanical Dynamic Characteristics of Knee Flexion Movement under Squatting

    Directory of Open Access Journals (Sweden)

    Jianping Wang

    2014-01-01

    Full Text Available The model of three-dimensional (3D geometric knee was built, which included femoral-tibial, patellofemoral articulations and the bone and soft tissues. Dynamic finite element (FE model of knee was developed to simulate both the kinematics and the internal stresses during knee flexion. The biomechanical experimental system of knee was built to simulate knee squatting using cadaver knees. The flexion motion and dynamic contact characteristics of knee were analyzed, and verified by comparing with the data from in vitro experiment. The results showed that the established dynamic FE models of knee are capable of predicting kinematics and the contact stresses during flexion, and could be an efficient tool for the analysis of total knee replacement (TKR and knee prosthesis design.

  15. Unique gene expression profile of the proliferating Xenopus tadpole tail blastema cells deciphered by RNA-sequencing analysis.

    Directory of Open Access Journals (Sweden)

    Hiroshi Tsujioka

    Full Text Available Organ regenerative ability depends on the animal species and the developmental stage. The molecular bases for variable organ regenerative ability, however, remain unknown. Previous studies have identified genes preferentially expressed in the blastema tissues in various animals, but transcriptome analysis of the isolated proliferating blastema cells has not yet been reported. In the present study, we used RNA-sequencing analysis to analyze the gene expression profile of isolated proliferating blastema cells of regenerating Xenopus laevis tadpole tails. We used flow cytometry to isolate proliferating cells, and non-proliferating blastema cells, from regenerating tadpole tails as well as proliferating tail bud cells from tail bud embryos, the latter two of which were used as control cells, based on their DNA content. Among the 28 candidate genes identified by RNA-sequencing analysis, quantitative reverse transcription-polymerase chain reaction identified 10 genes whose expression was enriched in regenerating tadpole tails compared with non-regenerating tadpole tails or tails from the tail bud embryos. Among them, whole mount in situ hybridization revealed that chromosome segregation 1-like and interleukin 11 were expressed in the broad area of the tail blastema, while brevican, lysyl oxidase, and keratin 18 were mainly expressed in the notochord bud in regenerating tails. We further combined whole mount in situ hybridization with immunohistochemistry for the incorporated 5-bromo-2-deoxyuridine to confirm that keratin 18 and interleukin 11 were expressed in the proliferating tail blastema cells. Based on the proposed functions of their homologs in other animal species, these genes might have roles in the extracellular matrix formation in the notochord bud (brevican and lysyl oxidase, cell proliferation (chromosome segregation 1-like and keratin 18, and in the maintenance of the differentiation ability of proliferating blastema cells (interleukin 11

  16. Segregation and differential settling in flocculated tailings

    Energy Technology Data Exchange (ETDEWEB)

    Farinato, R.S.; Mahmoudkhani, A.; Fenderson, T.; Watson, P. [Kemira, Atlanta, GA (United States)

    2010-07-01

    Untreated oil sands tailings have a high solids content, have poor dewaterability, and contain no aggregates. This PowerPoint presentation investigated segregation and differential settling in flocculated tailings. Tailings were treated with gypsum and various polymers. Cylinder settling, dynamic rheometry, particle size analysis, and microscopy techniques were used to characterize the composite tailings. The particles sizes of the samples were evaluated in relation to shear rate, bed depth, and treatment. The study showed that the gypsum-treated tailings had small aggregates, size stratification, a high solids content, and poor dewaterability. The polymer N-treated tailings had the lowest solids content, good dewaterability, and weak aggregates. The polymer A-treated tailings had a low solids content, very good dewaterability, and strong aggregates. The addition of a coagulant to the polymer-A treated tailings provided weaker aggregates and a higher solids content. tabs., figs.

  17. Health risks from uranium mill tailings

    International Nuclear Information System (INIS)

    Russell, J.L.

    1992-01-01

    This paper reviews the risk to public health and the environment from uranium mill tailings. The steps taken by the Environmental Protection Agency (EPA) to reduce this risk from tailing are summarized

  18. Are magnetic resonance flexion views useful in evaluating the cervical spine of patients with rheumatoid arthritis?

    Energy Technology Data Exchange (ETDEWEB)

    Reijnierse, M.; Kroon, H.M.; Bloem, J.L. [Dept. of Radiology, Leiden University Medical Center (Netherlands); Breedveld, F.C. [Dept. of Rheumatology, Leiden University Medical Center, Leiden (Netherlands); Hansen, B. [Dept. of Medical Statistics, Leiden University Medical Center, Leiden (Netherlands); Pope, T.L. [Dept. of Diagnostic Radiology, Bowman Gray School of Medicine, Winston-Salem (United States)

    2000-02-01

    Objective. To determine whether MR imaging in flexion adds value relative to imaging in the neutral position with respect to displaying involvement of the subarachnoid space, brainstem and spinal cord. Design and patients. T1-weighted MR images of the cervical spine in 42 rheumatoid arthritis patients with cervical spine involvement were obtained and analyzed prospectively. We assessed changes between images obtained in the neutral position and following active flexion, especially horizontal atlantoaxial and subaxial motion, presence or absence of brainstem compression, subarachnoid space involvement at the atlantoaxial and subaxial level and the cervicomedullary angle. Vertical atlantoaxial subluxation and the amount of pannus were correlated with motion and change in subarachnoid space. Results. The flexion images showed horizontal atlantoaxial motion in 21 patients and subaxial motion in one patient. The flexion view displayed brainstem compression in only one patient. Involvement of the subarachnoid space increased at the atlantoaxial level in eight (19%) patients (P=0.004) and at the level below C2 in five (12%) patients (P=0.03). There were no patients with a normal subarachnoid space in neutral position and compression in the flexed position. The cervicomedullary angle changed significantly with flexion. Vertical atlantoaxial subluxation and the amount of pannus did not show a significant correlation with motion or subarachnoid space involvement. Conclusion. MR imaging in the flexed position shows a statistically significant narrowing of the subarachnoid space at the atlantoaxial level and below C2. Cord compression is only observed on flexion views if the subarachnoid space in neutral position is already decreased. MR imaging in the flexed position might be useful, since subarachnoid space involvement may be an indicator for the development of neurologic dysfunction. (orig.)

  19. A Textile-Based Wearable Sensing Device Designed for Monitoring the Flexion Angle of Elbow and Knee Movements

    Directory of Open Access Journals (Sweden)

    Tien-Wei Shyr

    2014-02-01

    Full Text Available In this work a wearable gesture sensing device consisting of a textile strain sensor, using elastic conductive webbing, was designed for monitoring the flexion angle of elbow and knee movements. The elastic conductive webbing shows a linear response of resistance to the flexion angle. The wearable gesture sensing device was calibrated and then the flexion angle-resistance equation was established using an assembled gesture sensing apparatus with a variable resistor and a protractor. The proposed device successfully monitored the flexion angle during elbow and knee movements.

  20. Risk assessment of tailings facility dam failure

    OpenAIRE

    Hadzi-Nikolova, Marija; Mirakovski, Dejan; Stefanova, Violeta

    2011-01-01

    This paper presents the consequences of tailings facility dam failure and therefore the needs for its risk assessment. Tailings are fine-grained wastes of the mining industry, output as slurries, due to mixing with water during mineral processing. Tailings dams vary a lot as it is affected by: tailings characteristics and mill output, site characteristics as: topography, hydrology, geology, groundwater, seismicity and available material and disposal methods. The talings which accumulat...

  1. Bilateral Distal Femoral Flexion Deformity After Total Knee Arthroplasty in a Patient with Rheumatoid Arthritis

    Directory of Open Access Journals (Sweden)

    Jimmy Chan Chun-Ming

    2013-12-01

    Full Text Available Rheumatoid arthritis is an autoimmune systemic disease with predominant peripheral polyarthritis, often leading to severe joint destruction. This is a case report of an 81-year-old woman with long-standing severe rheumatoid arthritis requiring multiple orthopaedic operations for joint destruction since 2000. These operated joints improved her functional mobility until recently, when she found that her knees were fixed at around 70° of flexion with limited motion. There was chronic progressive flexion deformity of bilateral distal femurs, which was an extremely rare complication of total knee arthroplasty.

  2. Cylinder Symmetric Measures with the Tail Property

    NARCIS (Netherlands)

    Balkema, A.A.

    2006-01-01

    Abstract: A Pareto distribution has the property that any tail of the distribution has the same shape as the original distribution. The exponential distribution and the uniform distribution have the tail property too. The tail property characterizes the univariate generalized Pareto distributions.

  3. Microbial communities in low permeability, high pH uranium mine tailings: characterization and potential effects.

    Science.gov (United States)

    Bondici, V F; Lawrence, J R; Khan, N H; Hill, J E; Yergeau, E; Wolfaardt, G M; Warner, J; Korber, D R

    2013-06-01

    To describe the diversity and metabolic potential of microbial communities in uranium mine tailings characterized by high pH, high metal concentration and low permeability. To assess microbial diversity and their potential to influence the geochemistry of uranium mine tailings using aerobic and anaerobic culture-based methods, in conjunction with next generation sequencing and clone library sequencing targeting two universal bacterial markers (the 16S rRNA and cpn60 genes). Growth assays revealed that 69% of the 59 distinct culturable isolates evaluated were multiple-metal resistant, with 15% exhibiting dual-metal hypertolerance. There was a moderately positive correlation coefficient (R = 0·43, P tailings depth was shown to influence bacterial community composition, with the difference in the microbial diversity of the upper (0-20 m) and middle (20-40 m) tailings zones being highly significant (P tailings zone being significant (P tailings environment, along with their demonstrated capacity for transforming metal elements, suggests that these organisms have the potential to influence the long-term geochemistry of the tailings. This study is the first investigation of the diversity and functional potential of micro-organisms present in low permeability, high pH uranium mine tailings. © 2013 The Society for Applied Microbiology.

  4. Numerical modelling for stability of tailings dams

    OpenAIRE

    Auchar, Muhammad; Mattsson, Hans; Knutsson, Sven

    2013-01-01

    A tailings dam is a large embankment structure that is constructed to store the waste from the mining industry. Stability problems may occur in a tailings dam due to factors such as quick rate of raising, internal erosion and liquefaction. The failure of a tailings dam may cause loss of human life and environmental degradation. Tailings Dams must not only be stable during the time the tailings storage facility is in operation, but also long time after the mine is closed. In Sweden, the licens...

  5. Knee extension and flexion: MR delineation of normal and torn anterior cruciate ligaments

    Energy Technology Data Exchange (ETDEWEB)

    Niitsu, Mamoru; Ikeda, Kotaroh; Fukubayashi, Tohru; Anno, Izumi; Itai, Yuji [Univ. of Tsukuba, Ibaraki (Japan)

    1996-03-01

    Our goal was to assess the effect of joint position of semiflexed and extended knees in MR delineation of the anterior cruciate ligament (ACL). With a mobile knee brace and a flexible surface coil, the knee joint was either fully extended or bent to a semiflexed position (average 45{degrees} of flexion) within the magnet bore. Sets of oblique sagittal MR images were obtained for both extended and flexed knee positions. Thirty-two knees with intact ACLs and 43 knees with arthroscopically proven ACL tears were evaluated. Two observers compared paired MR images of both extended and flexed positions and rated them by a relative three point scale. Anatomic correlation in MR images was obtained by a cadaveric knee with incremental flexion. The MR images of flexed knees were more useful than of extended knees in 53% of the case reviews of femoral attachments and 36% of reviews of midportions of normal ACLs. Compared with knee extensions, the MR images for knee flexion provided better clarity in 48% of reviews of disrupted sites and 52% of residual bundles of torn ACLs. Normal ACL appeared taut in the knee extension and lax in semiflexion. Compared with MR images of knees in extension, MR images of knees in flexion more clearly delineate the femoral side of the ligament with wider space under the intercondylar roof and with decreased volume-averaging artifacts, providing superior visualization of normal and torn ACLs. 13 refs., 7 figs., 1 tab.

  6. Flexion-relaxation ratio in computer workers with and without chronic neck pain.

    Science.gov (United States)

    Pinheiro, Carina Ferreira; dos Santos, Marina Foresti; Chaves, Thais Cristina

    2016-02-01

    This study evaluated the flexion-relaxation phenomenon (FRP) and flexion-relaxation ratios (FR-ratios) using surface electromyography (sEMG) of the cervical extensor muscles of computer workers with and without chronic neck pain, as well as of healthy subjects who were not computer users. This study comprised 60 subjects 20-45years of age, of which 20 were computer workers with chronic neck pain (CPG), 20 were computer workers without neck pain (NPG), and 20 were control individuals who do not use computers for work and use them less than 4h/day for other purposes (CG). FRP and FR-ratios were analyzed using sEMG of the cervical extensors. Analysis of FR-ratios showed smaller values in the semispinalis capitis muscles of the two groups of workers compared to the control group. The reference FR-ratio (flexion relaxation ratio [FRR], defined as the maximum activity in 1s of the re-extension/full flexion sEMG activity) was significantly higher in the computer workers with neck pain compared to the CG (CPG: 3.10, 95% confidence interval [CI95%] 2.50-3.70; NPG: 2.33, CI95% 1.93-2.74; CG: 1.99, CI95% 1.81-2.17; pneck pain, and such results suggested that each FR-ratio could have a different application. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. 49 CFR 572.145 - Upper and lower torso assemblies and torso flexion test procedure.

    Science.gov (United States)

    2010-10-01

    ...) ANTHROPOMORPHIC TEST DEVICES 3-year-Old Child Crash Test Dummy, Alpha Version § 572.145 Upper and lower torso... lumbar spine and abdomen of a fully assembled dummy (drawing 210-0000) to flexion articulation between... in paragraph (c) of this section, the lumbar spine-abdomen assembly shall flex by an amount that...

  8. Impact of esophageal flexion level on the surgical outcome in patients with sigmoid esophageal achalasia.

    Science.gov (United States)

    Tsuboi, Kazuto; Omura, Nobuo; Yano, Fumiaki; Hoshino, Masato; Yamamoto, Se-Ryung; Akimoto, Shunsuke; Masuda, Takahiro; Kashiwagi, Hideyuki; Yanaga, Katsuhiko

    2017-11-01

    Esophageal achalasia can be roughly divided into non-sigmoid and sigmoid types. Laparoscopic surgery has been reported to be less than optimally effective for sigmoid type. The aim of this study was to examine the impact of the esophageal flexion level on the clinical condition and surgical outcomes of patients with sigmoid esophageal achalasia. The subjects were 36 patients with sigmoid esophageal achalasia who had been observed for >1 year after surgery. The subjects were divided into sigmoid type (Sg) and advanced sigmoid type (aSg) groups based on the flexion level of the lower esophagus to compare their clinical parameters and surgical outcomes. The Sg and aSg groups included 26 (72%) and 10 subjects, respectively. There were no marked differences in the clinical parameters or surgical outcomes between the two groups. However, the clearance rate calculated using the timed barium esophagogram was lower in the aSg group than in the Sg group. No differences were found in the postoperative symptom scores between the two groups, and both reported a high level of satisfaction. Although laparoscopic surgery for symptoms of sigmoid esophageal achalasia was highly successful regardless of the flexion level, the improvement in esophageal clearance was lower when the flexion level was higher.

  9. Evaluation of movements of lower limbs in non-professional ballet dancers: hip abduction and flexion

    Directory of Open Access Journals (Sweden)

    Valenti Erica E

    2011-08-01

    Full Text Available Abstract Background The literature indicated that the majority of professional ballet dancers present static and active dynamic range of motion difference between left and right lower limbs, however, no previous study focused this difference in non-professional ballet dancers. In this study we aimed to evaluate active movements of the hip in non-professional classical dancers. Methods We evaluated 10 non professional ballet dancers (16-23 years old. We measured the active range of motion and flexibility through Well Banks. We compared active range of motion between left and right sides (hip flexion and abduction and performed correlation between active movements and flexibility. Results There was a small difference between the right and left sides of the hip in relation to the movements of flexion and abduction, which suggest the dominant side of the subjects, however, there was no statistical significance. Bank of Wells test revealed statistical difference only between the 1st and the 3rd measurement. There was no correlation between the movements of the hip (abduction and flexion, right and left sides with the three test measurements of the bank of Wells. Conclusion There is no imbalance between the sides of the hip with respect to active abduction and flexion movements in non-professional ballet dancers.

  10. Evaluation of movements of lower limbs in non-professional ballet dancers: hip abduction and flexion

    Science.gov (United States)

    2011-01-01

    Background The literature indicated that the majority of professional ballet dancers present static and active dynamic range of motion difference between left and right lower limbs, however, no previous study focused this difference in non-professional ballet dancers. In this study we aimed to evaluate active movements of the hip in non-professional classical dancers. Methods We evaluated 10 non professional ballet dancers (16-23 years old). We measured the active range of motion and flexibility through Well Banks. We compared active range of motion between left and right sides (hip flexion and abduction) and performed correlation between active movements and flexibility. Results There was a small difference between the right and left sides of the hip in relation to the movements of flexion and abduction, which suggest the dominant side of the subjects, however, there was no statistical significance. Bank of Wells test revealed statistical difference only between the 1st and the 3rd measurement. There was no correlation between the movements of the hip (abduction and flexion, right and left sides) with the three test measurements of the bank of Wells. Conclusion There is no imbalance between the sides of the hip with respect to active abduction and flexion movements in non-professional ballet dancers. PMID:21819566

  11. Prior Knowledge Improves Decoding of Finger Flexion from Electrocorticographic (ECoG Signals

    Directory of Open Access Journals (Sweden)

    Zuoguan eWang

    2011-11-01

    Full Text Available Brain-computer interfaces (BCIs use brain signals to convey a user's intent. Some BCI approaches begin by decoding kinematic parameters of movements from brain signals, and then proceed to using these signals, in absence of movements, to allow a user to control an output. Recent results have shown that electrocorticographic (ECoG recordings from the surface of the brain in humans can give information about kinematic parameters (eg{} hand velocity or finger flexion. The decoding approaches in these studies usually employed classical classification/regression algorithms that derive a linear mapping between brain signals and outputs. However, they typically only incorporate little prior information about the target movement parameter. In this paper, we incorporate prior knowledge using a Bayesian decoding method, and use it to decode finger flexion from ECoG signals. Specifically, we exploit the anatomic constraints and dynamic constraints that govern finger flexion and incorporate these constraints in the construction, structure, and the probabilistic functions of the prior model of a switched non-parametric dynamic system (SNDS. Given a measurement model resulting from a traditional linear regression method, we decoded finger flexion using posterior estimation that combined the prior and measurement models. Our results show that the application of the Bayesian decoding model, which incorporates prior knowledge, improves decoding performance compared to the application of a linear regression model, which does not incorporate prior knowledge. Thus, the results presented in this paper may ultimately lead to neurally controlled hand prostheses with full fine-grained finger articulation.

  12. Thermal stabilization of uranium mill tailings

    International Nuclear Information System (INIS)

    Dreesen, D.R.; Williams, J.M.; Cokal, E.J.

    1981-01-01

    The sintering of tailings at high temperatures (1200 0 C) has shown promise as a conditioning approach that greatly reduces the 222 Rn emanation of uranium mill tailings. The structure of thermally stabilized tailings has been appreciably altered producing a material that will have minimal management requirements and will be applicable to on-site processing and disposal. The mineralogy of untreated tailings is presented to define the structure of the original materials. Quartz predominates in most tailings samples; however, appreciable quantities of gypsum, clay, illite, or albites are found in some tailings. Samples from the Durango and Shiprock sites have plagioclase-type aluminosilicates and non-aluminum silicates as major components. The iron-rich vanadium tailings from the Salt Lake City site contain appreciable quantities of α-hematite and chloroapatite. The reduction in radon emanation power and changes in mineralogy as a function of sintering temperature are presented

  13. Ecotoxicity of Mine Tailings: Unrehabilitated Versus Rehabilitated.

    Science.gov (United States)

    Maboeta, M S; Oladipo, O G; Botha, S M

    2018-05-01

    Earthworms are bioindicators of soil pollution. The ecotoxicity of tailings from selected gold mines in South Africa was investigated utilizing Eisenia andrei bioassays and biomarkers. Samples were obtained from unrehabilitated, rehabilitated and naturally vegetated sites. Biomass, neutral red retention time (NRRT), survival and reproduction were assessed using standardized protocols. Earthworm biomass, NRRT and reproductive success in rehabilitated tailings (comparable to naturally vegetated site) were significantly higher (p tailings. In addition, significantly lower (p tailings compared to the unrehabilitated. Further, significantly lower (p tailings than the rehabilitated and naturally vegetated sites. Overall, reduced ecotoxicity effects were confirmed in rehabilitated compared to unrehabilitated tailings. This suggests that rehabilitation as a post-mining restorative strategy has strong positive influence on mine tailings.

  14. Mineralogy and geochemistry of uranium mill tailings

    International Nuclear Information System (INIS)

    Pagel, M.; Somot, S.

    2002-01-01

    We have investigated three main types of uranium mill tailings: (1) acid mill tailings (Mounana, Gabon), (2) neutralized acid mill tailings (Ecarpiere and Jouac, France) and (3) alkaline mill tailings (Lodeve, France). We have focused especially on radium behaviour which is of major environmental concern in these tailings, but other metals were also studied. It is shown that in type 1 , trapping of 226 Ra by anglesite and barite is dominant whereas in types 2 and 3, 226 Ra is mainly or significantly scavenged by Fe- Mn oxyhydroxides. This study points out the importance of keeping conditions in which these oxyhydroxides will be stable for the long-term. Uranium would be also released during acidification of the tailings. This shows the importance to know more about the behavior of Ra during the crystallization of oxyhydroxides and during tailings diagenesis. Therefore, it is very important to study the sorption of Ra by clay minerals or late authigeneous minerals such as barite. (author)

  15. Intrathecal volume changes in lumbar spinal canal stenosis following extension and flexion: An experimental cadaver study.

    Science.gov (United States)

    Teske, Wolfram; Schwert, Martin; Zirke, Sonja; von Schulze Pellengahr, Christoph; Wiese, Matthias; Lahner, Matthias

    2015-01-01

    The spinal canal stenosis is a common disease in elderly. The thecal sac narrowing is considered as the anatomical cause for the disease. There is evidence that the anatomical proportions of the lumbar spinal canal are influenced by postural changes. The liquor volume shift during these postural changes is a valuable parameter to estimate the dynamic qualities of this disease. The aim of this human cadaver study was the determination of intrathecal fluid volume changes during the lumbar flexion and the extension. A special measuring device was designed and built for the study to investigate this issue under controlled conditions. The measuring apparatus fixed the lumbar spine firmly and allowed only flexion and extension. The dural sac was closed water tight. The in vitro changes of the intrathecal volumes during the motion cycle were determined according to the principle of communicating vessels. Thirteen human cadaver spines from the Institute of Anatomy were examined in a test setting with a continuous adjustment of motion. The diagnosis of the lumbar spinal stenosis was confirmed by a positive computer tomography prior testing. The volume changes during flexion and extension cycles were measured stepwise in a 2 degree distance between 18° flexion and 18° extension. Three complete series of measurements were performed for each cadaver. Two specimens were excluded because of fluid leaks from further investigation. The flexion of the lumbar spine resulted in an intrathecal volume increase. The maximum volume effects were seen in the early flexion positions of 2° and 4°. The spine reclination resulted in a volume reduction. The maximum extension effect was seen between 14° and 16°. According to our results, remarkable volume effects were seen in the early movements of the lumbar spine especially for the flexion. The results support the concept of the spinal stenosis as a dynamic disease and allow a better understanding of the pathophysiology of this

  16. Decoding subtle forearm flexions using fractal features of surface electromyogram from single and multiple sensors.

    Science.gov (United States)

    Arjunan, Sridhar Poosapadi; Kumar, Dinesh Kant

    2010-10-21

    Identifying finger and wrist flexion based actions using a single channel surface electromyogram (sEMG) can lead to a number of applications such as sEMG based controllers for near elbow amputees, human computer interface (HCI) devices for elderly and for defence personnel. These are currently infeasible because classification of sEMG is unreliable when the level of muscle contraction is low and there are multiple active muscles. The presence of noise and cross-talk from closely located and simultaneously active muscles is exaggerated when muscles are weakly active such as during sustained wrist and finger flexion. This paper reports the use of fractal properties of sEMG to reliably identify individual wrist and finger flexion, overcoming the earlier shortcomings. SEMG signal was recorded when the participant maintained pre-specified wrist and finger flexion movements for a period of time. Various established sEMG signal parameters such as root mean square (RMS), Mean absolute value (MAV), Variance (VAR) and Waveform length (WL) and the proposed fractal features: fractal dimension (FD) and maximum fractal length (MFL) were computed. Multi-variant analysis of variance (MANOVA) was conducted to determine the p value, indicative of the significance of the relationships between each of these parameters with the wrist and finger flexions. Classification accuracy was also computed using the trained artificial neural network (ANN) classifier to decode the desired subtle movements. The results indicate that the p value for the proposed feature set consisting of FD and MFL of single channel sEMG was 0.0001 while that of various combinations of the five established features ranged between 0.009 - 0.0172. From the accuracy of classification by the ANN, the average accuracy in identifying the wrist and finger flexions using the proposed feature set of single channel sEMG was 90%, while the average accuracy when using a combination of other features ranged between 58% and 73

  17. Decoding subtle forearm flexions using fractal features of surface electromyogram from single and multiple sensors

    Directory of Open Access Journals (Sweden)

    Kumar Dinesh

    2010-10-01

    Full Text Available Abstract Background Identifying finger and wrist flexion based actions using a single channel surface electromyogram (sEMG can lead to a number of applications such as sEMG based controllers for near elbow amputees, human computer interface (HCI devices for elderly and for defence personnel. These are currently infeasible because classification of sEMG is unreliable when the level of muscle contraction is low and there are multiple active muscles. The presence of noise and cross-talk from closely located and simultaneously active muscles is exaggerated when muscles are weakly active such as during sustained wrist and finger flexion. This paper reports the use of fractal properties of sEMG to reliably identify individual wrist and finger flexion, overcoming the earlier shortcomings. Methods SEMG signal was recorded when the participant maintained pre-specified wrist and finger flexion movements for a period of time. Various established sEMG signal parameters such as root mean square (RMS, Mean absolute value (MAV, Variance (VAR and Waveform length (WL and the proposed fractal features: fractal dimension (FD and maximum fractal length (MFL were computed. Multi-variant analysis of variance (MANOVA was conducted to determine the p value, indicative of the significance of the relationships between each of these parameters with the wrist and finger flexions. Classification accuracy was also computed using the trained artificial neural network (ANN classifier to decode the desired subtle movements. Results The results indicate that the p value for the proposed feature set consisting of FD and MFL of single channel sEMG was 0.0001 while that of various combinations of the five established features ranged between 0.009 - 0.0172. From the accuracy of classification by the ANN, the average accuracy in identifying the wrist and finger flexions using the proposed feature set of single channel sEMG was 90%, while the average accuracy when using a combination

  18. Potential virulence factors of bacteria associated with tail fan necrosis in the spiny lobster, Jasus edwardsii.

    Science.gov (United States)

    Zha, H; Jeffs, A; Dong, Y; Lewis, G

    2018-05-01

    Tail fan necrosis (TFN) is a common condition found in commercially exploited spiny lobsters that greatly diminishes their commercial value. Bacteria possessing proteolytic, chitinolytic and lipolytic capabilities were associated with TFN in spiny lobsters, Jasus edwardsii. In this study, 69 bacterial isolates exhibiting all the three enzymatic capabilities from the haemolymph and tail fans of J. edwardsii with and without TFN were further characterized and compared, including morphology, biofilm formation, antimicrobial activity, antimicrobial resistance, and production of siderophores, melanin and ammonia. The genomic patterns of the most common Vibrio crassostreae isolates were also compared between TFN-affected and unaffected lobsters. Biofilm formation was stronger in bacterial isolates from both haemolymph and tail fans of TFN-affected lobsters compared to those from the unaffected lobsters, while melanin production and siderophore production were stronger in the isolates from tail fans of lobsters with TFN. By contrast, the other characteristics of isolates were similar in lobsters with and without TFN. The Vib. crassostreae isolates from the affected lobsters had similar genomic patterns. Overall, the results indicate that in addition to proteolytic, chitinolytic and lipolytic activities, the bacteria associated with TFN commonly have enhanced activity of important virulence factors, including biofilm formation, melanin production and siderophore production. © 2018 John Wiley & Sons Ltd.

  19. Femoral loosening of high-flexion total knee arthroplasty: The effect of posterior cruciate ligament retention and bone quality reduction

    NARCIS (Netherlands)

    Zelle, J.; van de Groes, S.A.W.; De Waal Malefijt, M.C.; Verdonschot, Nicolaas Jacobus Joseph

    2014-01-01

    High-flexion total knee arthroplasty (TKA) may be more sensitive to femoral loosening than conventional TKA as the knee joint force increases during deep flexion. The objective of this study was to evaluate whether the probability of femoral loosening is equal in posterior cruciate ligament (PCL)

  20. Neck muscle fatigue alters the cervical flexion relaxation ratio in sub-clinical neck pain patients.

    Science.gov (United States)

    Zabihhosseinian, Mahboobeh; Holmes, Michael W R; Ferguson, Brad; Murphy, Bernadette

    2015-06-01

    The cervical flexion relaxation ratio is lower in neck pain patients compared to healthy controls. Fatigue modulates the onset and offset angles of the silent period in both the lumbar and cervical spine in healthy individuals; however, this response has not been studied with neck pain patients. The purpose of this study was to determine if cervical extensor fatigue would alter the parameters of the cervical flexion relaxation more in a neck pain group than a healthy control group. Thirteen healthy and twelve neck pain patients participated. Cervical extensor activity was examined bilaterally and kinematics of the neck and head were collected. An isometric, repetitive neck extension task at 70% of maximum elicited fatigue. Participants performed 3 trials of maximal cervical flexion both pre and post fatigue. The healthy controls and neck pain groups fatigued after 56 (41) and 39 (31) repetitions, respectively. There was a significant interaction effect for the flexion relaxation ratio between the control and neck pain groups from pre to post fatigue trials (F1,96=22.67, P=0.0001), but not for onset and offset angles (F1, 96=0.017, P=0.897), although the onset and offset angles did decrease significantly for both groups following fatigue (F1,96=9.26, P=0.002). Individuals with mild to moderate neck pain have significant differences in their neuromuscular control relative to controls, experienced myoelectric fatigue with fewer repetitions in a shorter time, had a lower cervical flexion relaxation ratio at baseline and had an inability to decrease this ratio further in response to fatigue. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Which is the most preventive measure against tail damage in finisher pigs: tail docking, straw provision or lowered stocking density?

    DEFF Research Database (Denmark)

    Larsen, Mona Lilian Vestbjerg; Andersen, Heidi Mai-Lis; Pedersen, Lene Juul

    2018-01-01

    One challenge of intensive pig production is tail damage caused by tail biting, and farmers often decrease the prevalence of tail damage through tail docking. However, tail docking is not an optimal preventive measure against tail damage and thus, it would be preferable to replace it. The aim of ...

  2. Scar-free wound healing and regeneration following tail loss in the leopard gecko, Eublepharis macularius.

    Science.gov (United States)

    Delorme, Stephanie Lynn; Lungu, Ilinca Mihaela; Vickaryous, Matthew Kenneth

    2012-10-01

    Many lizards are able to undergo scar-free wound healing and regeneration following loss of the tail. In most instances, lizard tail loss is facilitated by autotomy, an evolved mechanism that permits the tail to be self-detached at pre-existing fracture planes. However, it has also been reported that the tail can regenerate following surgical amputation outside the fracture plane. In this study, we used the leopard gecko, Eublepharis macularius, to investigate and compare wound healing and regeneration following autotomy at a fracture plane and amputation outside the fracture plane. Both forms of tail loss undergo a nearly identical sequence of events leading to scar-free wound healing and regeneration. Early wound healing is characterized by transient myofibroblasts and the formation of a highly proliferative wound epithelium immunoreactive for the wound keratin marker WE6. The new tail forms from what is commonly referred to as a blastema, a mass of proliferating mesenchymal-like cells. Blastema cells express the protease matrix metalloproteinase-9. Apoptosis (demonstrated by activated caspase 3 immunostaining) is largely restricted to isolated cells of the original and regenerating tail tissues, although cell death also occurs within dermal structures at the original-regenerated tissue interface and among clusters of newly formed myocytes. Furthermore, the autotomized tail is unique in demonstrating apoptosis among cells adjacent to the fracture planes. Unlike mammals, transforming growth factor-β3 is not involved in wound healing. We demonstrate that scar-free wound healing and regeneration are intrinsic properties of the tail, unrelated to the location or mode of tail detachment. Copyright © 2012 Wiley Periodicals, Inc.

  3. Characterization of oils sands thickened tailings

    Energy Technology Data Exchange (ETDEWEB)

    Scott, J.D.; Jeeravipoolvarn, S.; Donahue, R.; Ozum, B. [Alberta Univ., Edmonton, AB (Canada). Dept. of Civil and Environmental Engineering

    2008-07-01

    This presentation discussed the characterization of oils sands thickened tailings. The problem statement was defined as the fact that many laboratory procedures to characterize fine tailings do not take into account the extraction process, and instead use standardized laboratory tests. The purpose of this presentation was to demonstrate how different extraction processes affect the fine tailings geotechnical properties and water chemistry. Properties that were characterized included particle size analysis from hydrometer-sieve tests; per cent clay from methylene blue tests; per cent clay from mineralogy tests; Atterberg limits; water chemistry; and morphology by scanning electron microscopy. The presentation discussed the origin of fines (silt and clay) in tailings; where fine particles come from; tailings materials; mineralogy of tailings; the hydrometer-sieve test on fine tailings and thickened tailings; and the methylene blue test. It was concluded that the great majority of clay minerals in the tailings come from the clay-shale discontinuous seams and layers. For thickened tailings, the dispersed and non-dispersed hydrometer tests show considerable difference in the amount of clay size material. tabs., figs.

  4. Uranium mill tailings neutralization: contaminant complexation and tailings leaching studies

    International Nuclear Information System (INIS)

    Opitz, B.E.; Dodson, M.E.; Serne, R.J.

    1985-05-01

    Laboratory experiments were performed to compare the effectiveness of limestone (CaCO 3 ) and hydrated lime [Ca(OH) 2 ] for improving waste water quality through the neutralization of acidic uranium mill tailings liquor. The experiments were designed to also assess the effects of three proposed mechanisms - carbonate complexation, elevated pH, and colloidal particle adsorption - on the solubility of toxic contaminants found in a typical uranium mill waste solution. Of special interest were the effects each of these possible mechanisms had on the solution concentrations of trace metals such as Cd, Co, Mo, Zn, and U after neutralization. Results indicated that the neutralization of acidic tailings to a pH of 7.3 using hydrated lime provided the highest overall waste water quality. Both the presence of a carbonate source or elevating solution pH beyond pH = 7.3 resulted in a lowering of previously achieved water quality, while adsorption of contaminants onto colloidal particles was not found to affect the solution concentration of any constituent investigated. 24 refs., 8 figs., 19 tabs

  5. Controlled chaos: three-dimensional kinematics, fiber histochemistry, and muscle contractile dynamics of autotomized lizard tails.

    Science.gov (United States)

    Higham, Timothy E; Lipsett, Kathryn R; Syme, Douglas A; Russell, Anthony P

    2013-01-01

    The ability to shed an appendage occurs in both vertebrates and invertebrates, often as a tactic to avoid predation. The tails of lizards, unlike most autotomized body parts of animals, exhibit complex and vigorous movements once disconnected from the body. Despite the near ubiquity of autotomy across groups of lizards and the fact that this is an extraordinary event involving the self-severing of the spinal cord, our understanding of why and how tails move as they do following autotomy is sparse. We herein explore the histochemistry and physiology of the tail muscles of the leopard gecko (Eublepharis macularius), a species that exhibits vigorous and variable tail movements following autotomy. To confirm that the previously studied tail movements of this species are generally representative of geckos and therefore suitable for in-depth muscle studies, we quantified the three-dimensional kinematics of autotomized tails in three additional species. The movements of the tails of all species were generally similar and included jumps, flips, and swings. Our preliminary analyses suggest that some species of gecko exhibit short but high-frequency movements, whereas others exhibit larger-amplitude but lower-frequency movements. We then compared the ATPase and oxidative capacity of muscle fibers and contractile dynamics of isolated muscle bundles from original tails, muscle from regenerate tails, and fast fibers from an upper limb muscle (iliofibularis) of the leopard gecko. Histochemical analysis revealed that more than 90% of the fibers in original and regenerate caudal muscles had high ATPase but possessed a superficial layer of fibers with low ATPase and high oxidative capacity. We found that contraction kinetics, isometric force, work, power output, and the oscillation frequency at which maximum power was generated were lowest in the original tail, followed by the regenerate tail and then the fast fibers of the iliofibularis. Muscle from the original tail exhibited

  6. Finger island flaps for treatment of dermato-desmogenic flexion contractures of proximal interphalangeal joints

    Directory of Open Access Journals (Sweden)

    T. S. Antonova

    2016-12-01

    Full Text Available Soft tissue defect will form after operative treatment of the dermato-desmogenic flexion contractures of fingers interphalangeal joints of the 2–3 grades after excision of the scar. Using the island flaps (Littler at the central vascular pedicle is one of the classical methods of plastic closure of such defects. Goal. To study the effectiveness of the surgical treatment of dermato-desmogenic flexion contractures of proximal interphalangeal joints of the fingers by using finger island flaps at the central vascular or neuro-vascular pedicle. Materials and methods. 14 operations were carried out on 13 patients for removing dermato-desmogenic flexion contractures of proximal interphalangeal (PIP joints of triphalangeal fingers over a 2-year period (2013–2015. The group included patients with a flexion contracture of the 2–3 grades PIP joints of triphalangeal fingers. Operations were performed on average 5 months after the injury (from 1.5 up to 16 months. Finger island flap in all cases was taken from adjacent finger by using the blood supply of their common finger artery. In all cases the island flap on the central pedicel was used, in 9 cases digital nerve was included in the pedicle (Littler. Closure of donor wound was made with free-skin grafts. Permanent splinting of the hand with extension of the interphalangeal joints and moderate flexion of the metacarpophalangeal joints were performed during 7–8 days after surgery, then exercise therapy was prescribed. Results. The results were estimated 6 and 12 months after surgery. All the results were regarded as excellent. In 5 cases of using the flap on a vascular pedicle flap hypoesthesia was detected, that has not led to dysfunction of the hand. Contracture recurrence during follow-up was not observed. Conclusions. Using the surgery for treatment of dermato-desmogenic flexion contractures of proximal interphalangeal joints of the fingers with the island flaps at the central vascular or neuro

  7. Blood pressure and calf muscle oxygen extraction during plantar flexion exercise in peripheral artery disease.

    Science.gov (United States)

    Luck, J Carter; Miller, Amanda J; Aziz, Faisal; Radtka, John F; Proctor, David N; Leuenberger, Urs A; Sinoway, Lawrence I; Muller, Matthew D

    2017-07-01

    Peripheral artery disease (PAD) is an atherosclerotic vascular disease that affects 200 million people worldwide. Although PAD primarily affects large arteries, it is also associated with microvascular dysfunction, an exaggerated blood pressure (BP) response to exercise, and high cardiovascular mortality. We hypothesized that fatiguing plantar flexion exercise that evokes claudication elicits a greater reduction in skeletal muscle oxygenation (SmO 2 ) and a higher rise in BP in PAD compared with age-matched healthy subjects, but low-intensity steady-state plantar flexion elicits similar responses between groups. In the first experiment, eight patients with PAD and eight healthy controls performed fatiguing plantar flexion exercise (from 0.5 to 7 kg for up to 14 min). In the second experiment, seven patients with PAD and seven healthy controls performed low-intensity plantar flexion exercise (2.0 kg for 14 min). BP, heart rate (HR), and SmO 2 were measured continuously using near-infrared spectroscopy (NIRS). SmO 2 is the ratio of oxygenated hemoglobin to total hemoglobin, expressed as a percent. At fatigue, patients with PAD had a greater increase in mean arterial BP (18 ± 2 vs. vs. 10 ± 2 mmHg, P = 0.029) and HR (14 ± 2 vs. 6 ± 2 beats/min, P = 0.033) and a greater reduction in SmO 2 (-54 ± 10 vs. -12 ± 4%, P = 0.001). However, both groups had similar physiological responses to low-intensity, nonpainful plantar flexion exercise. These data suggest that patients with PAD have altered oxygen uptake and/or utilization during fatiguing exercise coincident with an augmented BP response. NEW & NOTEWORTHY In this laboratory study, patients with peripheral artery disease performed plantar flexion exercise in the supine posture until symptoms of claudication occurred. Relative to age- and sex-matched healthy subjects we found that patients had a higher blood pressure response, a higher heart rate response, and a greater reduction in skeletal muscle oxygenation as

  8. Radon emanation characteristics of uranium mill tailings

    International Nuclear Information System (INIS)

    Nielson, K.K.; Freeman, H.D.; Hartley, J.N.; Mauch, M.L.; Rogers, V.C.

    1982-01-01

    Radon emanation from uranium mill tailings was examined with respect to the mechanisms of emanation and the physical properties of the tailings which affect emanation. Radon emanation coefficients were measured at ambient moisture on 135 samples from the 1981 field test site at the Grand Junction tailings pile. These coefficients showed a similar trend with moisture to those observed previously with uranium ores, and averaged 0.10 + or - 0.02 at dryness and 0.38 + or - 0.04 for all samples having greater than five weight-percent moisture. Small differences were noted between the maximum values of the coefficients for the sand and slime fractions of the tailings. Separate measurements on tailings from the Vitro tailings pile exhibited much lower emanation coefficients for moist samples, and similar coefficients for dry samples. Alternative emanation measurement techniques were examined and procedures are recommended for use in future work

  9. Molecular ions in comet tails

    International Nuclear Information System (INIS)

    Wyckoff, S.; Wehinger, P.A.

    1976-01-01

    Band intensities of the molecular ions CH + , CO + , N 2 + , and H 2 O + have been determined on an absolute scale from tail spectra of comet Kohoutek (1973f) and comet Bradfield (1974b). Photoionization and photodissociation rates have been computed for CH, CO, and N 2 . Also emission rate excitation g-factors for (1) photoionization plus excitation and (2) resonance fluorescence have been computed for the observed ions. It is shown that resonance fluorescence is the dominant excitation mechanism for observed comet tail ions at rapprox. =1 AU. Band system luminosities and molecular ion abundances within a projected nuclear distance rho 4 km have been determined for CH + , CO + , N 2 + , and H 2 O + in comet Kohoutek, and for H 2 O + in comet Bradfield. Estimates are also given for column densities of all observed ions at rhoapprox. =10 4 km on the tailward side of the coma. The observed H 2 O + column densities were found to be roughly the same in comet Kohoutek and comet Bradfield et equal heliocentric distances, while CO + was found to be approximately 100 times more abundant than H 2 O + , N 2 + , and CH + at rhoapprox. =10 4 km in comet Kohoutek. Finally, the relative abundances of the observed ions and of the presumed parent neutral species are briefly discussed

  10. Oil sands tailings management project

    Energy Technology Data Exchange (ETDEWEB)

    Godwalt, C. [Alberta WaterSMART, Calgary, AB (Canada); Kotecha, P. [Suncor Energy Inc, Calgary, AB (Canada); Aumann, C. [Alberta Innovates - Technology Futures, Alberta Governement, AB (Canada)

    2010-11-15

    The Oil sands leadership initiative (OSLI) works with the Government of Alberta on the development of the oil sands industry, considering environmental, economical and social aspects. Water management was identified as one of most important areas to focus on. Alberta WaterSMART was requested to support the development and the management of projects resulting from the work done or underway in this field. The development of a regional water management solution stood out as the most interesting solution to obtain significant results. In the Athabasca Region, oil sands producers work independently on their water sourcing and disposal with particular attention to fresh water conservation and economics. The Athabasca River represents a source for mines and distant saline aquifers are the target of steam assisted gravity drainage (SAGD) operators. As part of a four-phase project aiming to study the environmental and economic footprint (EEF) benefit of alternatives for Athabasca oil sands production water supply and disposal, the purpose of the tailings water management project was to identify tailings treatment technologies that are ready to be implemented, and to design and evaluate solutions in order to improve regional oil sands production water sourcing and disposal. Alternatives were evaluated based on their total EEF, applying a lifecycle assessment methodology with a particular attention on the quantification of important performance indicators. 25 refs., 8 tabs., 40 figs.

  11. Oil sands tailings management project

    International Nuclear Information System (INIS)

    Godwalt, C.; Kotecha, P.; Aumann, C.

    2010-11-01

    The Oil sands leadership initiative (OSLI) works with the Government of Alberta on the development of the oil sands industry, considering environmental, economical and social aspects. Water management was identified as one of most important areas to focus on. Alberta WaterSMART was requested to support the development and the management of projects resulting from the work done or underway in this field. The development of a regional water management solution stood out as the most interesting solution to obtain significant results. In the Athabasca Region, oil sands producers work independently on their water sourcing and disposal with particular attention to fresh water conservation and economics. The Athabasca River represents a source for mines and distant saline aquifers are the target of steam assisted gravity drainage (SAGD) operators. As part of a four-phase project aiming to study the environmental and economic footprint (EEF) benefit of alternatives for Athabasca oil sands production water supply and disposal, the purpose of the tailings water management project was to identify tailings treatment technologies that are ready to be implemented, and to design and evaluate solutions in order to improve regional oil sands production water sourcing and disposal. Alternatives were evaluated based on their total EEF, applying a lifecycle assessment methodology with a particular attention on the quantification of important performance indicators. 25 refs., 8 tabs., 40 figs.

  12. Assessing Risks of Mine Tailing Dam Failures

    Science.gov (United States)

    Concha Larrauri, P.; Lall, U.

    2017-12-01

    The consequences of tailings dam failures can be catastrophic for communities and ecosystems in the vicinity of the dams. The failure of the Fundão tailings dam at the Samarco mine in 2015 killed 19 people with severe consequences for the environment. The financial and legal consequences of a tailings dam failure can also be significant for the mining companies. For the Fundão tailings dam, the company had to pay 6 billion dollars in fines and twenty-one executives were charged with qualified murder. There are tenths of thousands of active, inactive, and abandoned tailings dams in the world and there is a need to better understand the hazards posed by these structures to downstream populations and ecosystems. A challenge to assess the risks of tailings dams in a large scale is that many of them are not registered in publicly available databases and there is little information about their current physical state. Additionally, hazard classifications of tailings dams - common in many countries- tend to be subjective, include vague parameter definitions, and are not always updated over time. Here we present a simple methodology to assess and rank the exposure to tailings dams using ArcGIS that removes subjective interpretations. The method uses basic information such as current dam height, storage volume, topography, population, land use, and hydrological data. A hazard rating risk was developed to compare the potential extent of the damage across dams. This assessment provides a general overview of what in the vicinity of the tailings dams could be affected in case of a failure and a way to rank tailings dams that is directly linked to the exposure at any given time. One hundred tailings dams in Minas Gerais, Brazil were used for the test case. This ranking approach could inform the risk management strategy of the tailings dams within a company, and when disclosed, it could enable shareholders and the communities to make decisions on the risks they are taking.

  13. Comparison of the Hamstring Muscle Activity and Flexion-Relaxation Ratio between Asymptomatic Persons and Computer Work-related Low Back Pain Sufferers.

    Science.gov (United States)

    Kim, Min-Hee; Yoo, Won-Gyu

    2013-05-01

    [Purpose] The purpose of this study was to compare the hamstring muscle (HAM) activities and flexion-relaxation ratios of an asymptomatic group and a computer work-related low back pain (LBP) group. [Subjects] For this study, we recruited 10 asymptomatic computer workers and 10 computer workers with work-related LBP. [Methods] We measured the RMS activity of each phase (flexion, full-flexion, and re-extension phase) of trunk flexion and calculated the flexion-relaxation (FR) ratio of the muscle activities of the flexion and full-flexion phases. [Results] In the computer work-related LBP group, the HAM muscle activity increased during the full-flexion phase compared to the asymptomatic group, and the FR ration was also significantly higher. [Conclusion] We thought that prolonged sitting of computer workers might cause the change in their HAM muscle activity pattern.

  14. Average configuration of the geomagnetic tail

    International Nuclear Information System (INIS)

    Fairfield, D.H.

    1979-01-01

    Over 3000 hours of Imp 6 magnetic field data obtained between 20 and 33 R/sub E/ in the geomagnetic tail have been used in a statistical study of the tail configuration. A distribution of 2.5-min averages of B/sub z/ as a function of position across the tail reveals that more flux crosses the equatorial plane near the dawn and dusk flanks (B-bar/sub z/=3.γ) than near midnight (B-bar/sub z/=1.8γ). The tail field projected in the solar magnetospheric equatorial plane deviates from the x axis due to flaring and solar wind aberration by an angle α=-0.9 Y/sub SM/-2.7, where Y/sub SM/ is in earth radii and α is in degrees. After removing these effects, the B/sub y/ component of the tail field is found to depend on interplanetary sector structure. During an 'away' sector the B/sub y/ component of the tail field is on average 0.5γ greater than that during a 'toward' sector, a result that is true in both tail lobes and is independent of location across the tail. This effect means the average field reversal between northern and southern lobes of the tail is more often 178 0 rather than the 180 0 that is generally supposed

  15. Unique structural features facilitate lizard tail autotomy.

    Science.gov (United States)

    Sanggaard, Kristian W; Danielsen, Carl Chr; Wogensen, Lise; Vinding, Mads S; Rydtoft, Louise M; Mortensen, Martin B; Karring, Henrik; Nielsen, Niels Chr; Wang, Tobias; Thøgersen, Ida B; Enghild, Jan J

    2012-01-01

    Autotomy refers to the voluntary shedding of a body part; a renowned example is tail loss among lizards as a response to attempted predation. Although many aspects of lizard tail autotomy have been studied, the detailed morphology and mechanism remains unclear. In the present study, we showed that tail shedding by the Tokay gecko (Gekko gecko) and the associated extracellular matrix (ECM) rupture were independent of proteolysis. Instead, lizard caudal autotomy relied on biological adhesion facilitated by surface microstructures. Results based on bio-imaging techniques demonstrated that the tail of Gekko gecko was pre-severed at distinct sites and that its structural integrity depended on the adhesion between these segments.

  16. Unique structural features facilitate lizard tail autotomy

    DEFF Research Database (Denmark)

    Sanggaard, Kristian W; Danielsen, Carl Chr; Wogensen, Lise

    2012-01-01

    Autotomy refers to the voluntary shedding of a body part; a renowned example is tail loss among lizards as a response to attempted predation. Although many aspects of lizard tail autotomy have been studied, the detailed morphology and mechanism remains unclear. In the present study, we showed...... that tail shedding by the Tokay gecko (Gekko gecko) and the associated extracellular matrix (ECM) rupture were independent of proteolysis. Instead, lizard caudal autotomy relied on biological adhesion facilitated by surface microstructures. Results based on bio-imaging techniques demonstrated that the tail...

  17. Global analysis of sagittal spinal alignment in major deformities: correlation between lack of lumbar lordosis and flexion of the knee.

    Science.gov (United States)

    Obeid, Ibrahim; Hauger, Olivier; Aunoble, Stéphane; Bourghli, Anouar; Pellet, Nicolas; Vital, Jean-Marc

    2011-09-01

    It has become well recognised that sagittal balance of the spine is the result of an interaction between the spine and the pelvis. Knee flexion is considered to be the last compensatory mechanism in case of sagittal imbalance, but only few studies have insisted on the relationship between spino-pelvic parameters and lower extremity parameters. Correlation between the lack of lumbar lordosis and knee flexion has not yet been established. A retrospective study was carried out on 28 patients with major spinal deformities. The EOS system was used to measure spinal and pelvic parameters and the knee flexion angle; the lack of lumbar lordosis was calculated after prediction of lumbar lordosis with two different formulas. Correlation analysis between the different measured parameters was performed. Lumbar lordosis correlated with sacral slope (r = -0.71) and moderately with knee flexion angle (r = 0.42). Pelvic tilt correlated moderately with knee flexion angle (r = 0.55). Lack of lumbar lordosis correlated best with knee flexion angle (r = 0.72 and r = 0.63 using the two formulas, respectively). Knee flexion as a compensatory mechanism to sagittal imbalance was well correlated to the lack of lordosis and, depending on the importance of the former parameter, the best procedure to correct sagittal imbalance could be chosen.

  18. Pneumatic-type dynamic traction and flexion splint for treating patients with extension contracture of the metacarpophalangeal joint.

    Science.gov (United States)

    Nakayama, Jun; Horiki, Mituru; Denno, Kakurou; Ogawa, Kazunori; Oka, Hisao; Domen, Kazuhisa

    2016-02-01

    Collateral ligament shortening causes extension contractures of the metacarpophalangeal joint, and dynamic flexion splinting has been widely used to treat these contractures; however, there are various problems with these approaches. We developed a novel, pneumatic-type dynamic traction and flexion splint to solve these problems. A total of 25 fingers were treated with the dynamic traction and flexion splint for 8 weeks. Every 2 weeks, the average metacarpophalangeal joint flexion angle, total active motion, grasp strength, and pain scores were assessed. The finger flexion angle was significantly greater at the final evaluation, starting after 6 weeks of treatment (p < 0.05), than prior to treatment. Similarly, the total active motion results improved significantly over 8 weeks. Our results show that use of the dynamic traction and flexion splint improves patient finger functioning and flexural angle. The dynamic traction and flexion (DTF) splint appears to be effective for treating patients. © The International Society for Prosthetics and Orthotics 2015.

  19. Design of a wearable hand exoskeleton for exercising flexion/extension of the fingers.

    Science.gov (United States)

    Jo, Inseong; Lee, Jeongsoo; Park, Yeongyu; Bae, Joonbum

    2017-07-01

    In this paper, design of a wearable hand exoskeleton system for exercising flexion/extension of the fingers, is proposed. The exoskeleton was designed with a simple and wearable structure to aid finger motions in 1 degree of freedom (DOF). A hand grasping experiment by fully-abled people was performed to investigate general hand flexion/extension motions and the polynomial curve of general hand motions was obtained. To customize the hand exoskeleton for the user, the polynomial curve was adjusted to the joint range of motion (ROM) of the user and the optimal design of the exoskeleton structure was obtained using the optimization algorithm. A prototype divided into two parts (one part for the thumb, the other for rest fingers) was actuated by only two linear motors for compact size and light weight.

  20. Malposition of the tibial tubercle during flexion in knees with patellofemoral arthritis

    International Nuclear Information System (INIS)

    Nagamine, R.; Miura, H.; Tanaka, K.; Urabe, K.; Iwamoto, Y.; Inoue, Y.; Okamoto, Y.; Nishizawa, M.

    1997-01-01

    Objective. To assess the mechanisms contributing to the induction of patellofemoral arthritis (PF-OA). Design and patients. A computed tomography scan was taken at three levels of the lower extremity in full extension and at 30 of flexion. The cuts were superimposed and 12 parameters were compared in 17 PF-OA knees and 27 normal knees to assess the rotation angle of the tibial tubercle. Results. Although the tibial tubercle was in almost the same position in full extensioin in the normal and PF-OA knees, it was positioned significantly laterally at 30 of flexion in PF-OA knees. Also the articular surface of the lateral femoral condyle was significantly narrower or steeper in PF-OA knees. Conclusion. Anatomic variations and mechanical abnormalities were identified in the PF-OA knees. (orig.)

  1. Malposition of the tibial tubercle during flexion in knees with patellofemoral arthritis

    Energy Technology Data Exchange (ETDEWEB)

    Nagamine, R.; Miura, H.; Tanaka, K.; Urabe, K.; Iwamoto, Y. [Department of Orthopaedic Surgery, Kyushu Univ. (Japan); Inoue, Y.; Okamoto, Y.; Nishizawa, M. [Department of Orthopaedic Surgery, JR Kyushu Hospital, Kitakyushu City (Japan)

    1997-10-01

    Objective. To assess the mechanisms contributing to the induction of patellofemoral arthritis (PF-OA). Design and patients. A computed tomography scan was taken at three levels of the lower extremity in full extension and at 30 of flexion. The cuts were superimposed and 12 parameters were compared in 17 PF-OA knees and 27 normal knees to assess the rotation angle of the tibial tubercle. Results. Although the tibial tubercle was in almost the same position in full extensioin in the normal and PF-OA knees, it was positioned significantly laterally at 30 of flexion in PF-OA knees. Also the articular surface of the lateral femoral condyle was significantly narrower or steeper in PF-OA knees. Conclusion. Anatomic variations and mechanical abnormalities were identified in the PF-OA knees. (orig.) With 8 figs., 1 tab., 11 refs.

  2. MRI-based analysis of patellofemoral cartilage contact, thickness, and alignment in extension, and during moderate and deep flexion.

    Science.gov (United States)

    Freedman, Benjamin R; Sheehan, Frances T; Lerner, Amy L

    2015-10-01

    Several factors are believed to contribute to patellofemoral joint function throughout knee flexion including patellofemoral (PF) kinematics, contact, and bone morphology. However, data evaluating the PF joint in this highly flexed state have been limited. Therefore, the purpose of this study was to evaluate patellofemoral contact and alignment in low (0°), moderate (60°), and deep (140°) knee flexion, and then correlate these parameters to each other, as well as to femoral morphology. Sagittal magnetic resonance images were acquired on 14 healthy female adult knees (RSRB approved) using a 1.5 T scanner with the knee in full extension, mid-flexion, and deep flexion. The patellofemoral cartilage contact area, lateral contact displacement (LCD), cartilage thickness, and lateral patellar displacement (LPD) throughout flexion were defined. Intra- and inter-rater repeatability measures were determined. Correlations between patellofemoral contact parameters, alignment, and sulcus morphology were calculated. Measurement repeatability ICCs ranged from 0.94 to 0.99. Patellofemoral cartilage contact area and thickness, LCD, and LPD were statistically different throughout all levels of flexion (ppatellofemoral joint throughout its range of motion. This study agrees with past studies that investigated patellofemoral measures at a single flexion angle, and provides new insights into the relationship between patellofemoral contact and alignment at multiple flexion angles. The study provides a detailed analysis of the patellofemoral joint in vivo, and demonstrates the feasibility of using standard clinical magnetic resonance imaging scanners to image the knee joint in deep flexion. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Isolated posterior dislocation of the radial head in an adult.

    Directory of Open Access Journals (Sweden)

    Negi A

    1992-07-01

    Full Text Available Isolated posterior dislocation of the radial head was detected on X-ray in a patient following a vehicular accident. Such a dislocation without an associated fracture is extremely rare in adults. Immobilization of the elbow in full pronation and 90 degrees flexion for 4 weeks normalized the position of the head of the radius.

  4. Lateral movements of a massive tail influence gecko locomotion: an integrative study comparing tail restriction and autotomy

    OpenAIRE

    Jagnandan, Kevin; Higham, Timothy E.

    2017-01-01

    Tails are an intricate component of the locomotor system for many vertebrates. Leopard geckos (Eublepharis macularius) possess a large tail that is laterally undulated during steady locomotion. However, the tail is readily shed via autotomy, resulting in the loss of tail function, loss in body mass, and a cranial shift in the center of mass. To elucidate the function of tail undulations, we investigated changes in limb kinematics after manipulating the tail artificially by restricting tail un...

  5. Modification of Knee Flexion Angle Has Patient-Specific Effects on Anterior Cruciate Ligament Injury Risk Factors During Jump Landing.

    Science.gov (United States)

    Favre, Julien; Clancy, Caitlin; Dowling, Ariel V; Andriacchi, Thomas P

    2016-06-01

    The incidence of anterior cruciate ligament (ACL) injuries may be decreased through the use of intervention programs that focus on increasing the knee flexion angle during jump landing, which decreases strain on the ACL. To investigate whether intervention training designed to change the knee flexion angle during landing causes secondary changes in other known measures associated with the risk of ACL injuries and to examine the time points when these secondary measures change. Controlled laboratory study. A total of 39 healthy recreational athletes performed a volleyball block jump task in an instrumented gait laboratory. The participants first completed the jumps without any modification to their normal landing technique. They were then given oral instruction to land softly and to increase their knee flexion angle during landing. Lower body kinematics and kinetics were measured before and after the modification using an optoelectronic motion capture system. The knee flexion angle after the modification significantly increased from 11.2° to 15.2° at initial contact and from 67.8° to 100.7° at maximum flexion, and the time between initial contact and maximum flexion increased from 177.4 to 399.4 milliseconds. The flexion modification produced a substantial reduction in vertical ground-reaction force (243.1 to 187.8 %BW) with a concomitant reduction in the maximum flexion moment. Interestingly, the flexion modification only affected the abduction angle and abduction moment for the group of participants that landed in an initial adducted position before the modification and had no significant effect on the group that landed in an abducted position. Increasing the knee flexion angle during jump landing may be an effective intervention to improve knee biomechanical risk factors associated with an ACL injury. However, the fact that the flexion modification only influenced critical risk factors (the abduction angle and abduction moment) in participants who initially

  6. Normal postural responses preceding shoulder flexion: co-activation or asymmetric activation of transverse abdominis?

    Science.gov (United States)

    Davarian, Sanaz; Maroufi, Nader; Ebrahimi, Esmaeil; Parnianpour, Mohammad; Farahmand, Farzam

    2014-01-01

    It is suggested that activation of the transverse abdominis muscle has a stabilizing effect on the lumbar spine by raising intra-abdominal pressure without added disc compression. However, its feedforward activity has remained a controversial issue. In addition, research regarding bilateral activation of trunk muscles during a unilateral arm movement is limited. The aim of this study was to evaluate bilateral anticipatory activity of trunk muscles during unilateral arm flexion. Eighteen healthy subjects (aged 25 ± 3.96 years) participated in this study and performed 10 trials of rapid arm flexion in response to a visual stimulus. The electromyographic activity of the right anterior deltoid (AD) and bilateral trunk muscles including the transverse abdominis/internal oblique (TA/IO), superficial lumbar multifidus (SLM) and lumbar erector spine (LES) was recorded. The onset latency and anticipatory activity of the recorded trunk muscles were calculated. The first muscle activated in anticipation of the right arm flexion was the left TA/IO. The right TA/IO activated significantly later than all other trunk muscles (P 0.05). Healthy subjects showed no bilateral anticipatory co-activation of TA/IO in unilateral arm elevation. Further investigations are required to delineate normal muscle activation pattern in healthy subjects prior to prescribing bilateral activation training of transverse abdominis for subjects with chronic low back pain.

  7. Muscle changes in brachial plexus birth injury with elbow flexion contracture: an MRI study

    Energy Technology Data Exchange (ETDEWEB)

    Poeyhiae, Tiina H; Koivikko, Mika P; Lamminen, Antti E [University of Helsinki, Helsinki Medical Imaging Center, Helsinki (Finland); Peltonen, Jari I; Nietosvaara, A Y [Helsinki University Central Hospital, Hospital for Children and Adolescents, Helsinki (Finland); Kirjavainen, Mikko O [Helsinki University Central Hospital, Department of Orthopaedics and Traumatology, Helsinki (Finland)

    2007-02-15

    Muscle pathology of the arm and forearm in brachial plexus birth injury (BPBI) with elbow flexion contracture has not been evaluated with MRI. To determine whether limited range of motion of the elbow in BPBI is correlated with specific patterns of muscular pathology. For 15 BPBI patients, total active motion (TAM) of the elbow (extension-flexion) and the forearm (pronation-supination) were measured. MRI of the elbow joints and musculature allowed assessment of elbow congruency. Fatty infiltration and size reduction of the muscles were graded semiquantitatively. Mean TAM of the elbow was 113 (50 -140 ) and that of the forearm 91 (10 -165 ). The greater the size reduction of the brachioradialis muscle, the more diminished was elbow TAM. The more extensive the BPBI and muscle pathology of the pronator teres muscle, the more limited was the TAM of the forearm. Pathology of the supinator and brachialis muscles was evident in every patient. Extensive BPBI may result in marked limitation of TAM. Elbow flexion contracture seems to be caused mainly by brachialis muscle pathology. Prosupination of the forearm is better preserved when the pronator teres is not severely affected. MRI can reliably show the extent of muscle pathology in BPBI. (orig.)

  8. Detection method of flexion relaxation phenomenon based on wavelets for patients with low back pain

    Science.gov (United States)

    Nougarou, François; Massicotte, Daniel; Descarreaux, Martin

    2012-12-01

    The flexion relaxation phenomenon (FRP) can be defined as a reduction or silence of myoelectric activity of the lumbar erector spinae muscle during full trunk flexion. It is typically absent in patients with chronic low back pain (LBP). Before any broad clinical utilization of this neuromuscular response can be made, effective, standardized, and accurate methods of identifying FRP limits are needed. However, this phenomenon is clearly more difficult to detect for LBP patients than for healthy patients. The main goal of this study is to develop an automated method based on wavelet transformation that would improve time point limits detection of surface electromyography signals of the FRP in case of LBP patients. Conventional visual identification and proposed automated methods of time point limits detection of relaxation phase were compared on experimental data using criteria of accuracy and repeatability based on physiological properties. The evaluation demonstrates that the use of wavelet transform (WT) yields better results than methods without wavelet decomposition. Furthermore, methods based on wavelet per packet transform are more effective than algorithms employing discrete WT. Compared to visual detection, in addition to demonstrating an obvious saving of time, the use of wavelet per packet transform improves the accuracy and repeatability in the detection of the FRP limits. These results clearly highlight the value of the proposed technique in identifying onset and offset of the flexion relaxation response in LBP subjects.

  9. Segmental lumbar spine instability at flexion-extension radiography can be predicted by conventional radiography

    Energy Technology Data Exchange (ETDEWEB)

    Pitkaenen, M.T.; Manninen, H.I.; Lindgren, K.-A.J.; Sihvonen, T.A.; Airaksinen, O.; Soimakallio, S

    2002-07-01

    AIM: To identify plain radiographic findings that predict segmental lumbar spine instability as shown by functional flexion-extension radiography. MATERIALS AND METHODS: Plain radiographs and flexion-extension radiographs of 215 patients with clinically suspected lumbar spine instability were analysed. Instability was classified into anterior or posterior sliding instability. The registered plain radiographic findings were traction spur, spondylarthrosis, arthrosis of facet joints, disc degeneration, retrolisthesis, degenerative spondylolisthesis, spondylolytic spondylolisthesis and vacuum phenomena. Factors reaching statistical significance in univariate analyses (P < 0.05) were included in stepwise multiple logistic regression analysis. RESULTS: Degenerative spondylolisthesis (P = 0.004 at L3-4 level and P = 0.017 at L4-5 level in univariate analysis and odds ratio 16.92 at L4-5 level in multiple logistic regression analyses) and spondylolytic spondylolisthesis (P = 0.003 at L5-S1 level in univariate analyses) were the strongest independent determinants of anterior sliding instability. Retrolisthesis (odds ratio 10.97), traction spur (odds ratio 4.45) and spondylarthrosis (odds ratio 3.20) at L3-4 level were statistically significant determinants of posterior sliding instability in multivariate analysis. CONCLUSION: Sliding instability is strongly associated with various plain radiographic findings. In mechanical back pain, functional flexion-extension radiographs should be limited to situations when symptoms are not explained by findings of plain radiographs and/or when they are likely to alter therapy. Pitkaenen, M.T. et al. (2002)

  10. Segmental lumbar spine instability at flexion-extension radiography can be predicted by conventional radiography

    International Nuclear Information System (INIS)

    Pitkaenen, M.T.; Manninen, H.I.; Lindgren, K.-A.J.; Sihvonen, T.A.; Airaksinen, O.; Soimakallio, S.

    2002-01-01

    AIM: To identify plain radiographic findings that predict segmental lumbar spine instability as shown by functional flexion-extension radiography. MATERIALS AND METHODS: Plain radiographs and flexion-extension radiographs of 215 patients with clinically suspected lumbar spine instability were analysed. Instability was classified into anterior or posterior sliding instability. The registered plain radiographic findings were traction spur, spondylarthrosis, arthrosis of facet joints, disc degeneration, retrolisthesis, degenerative spondylolisthesis, spondylolytic spondylolisthesis and vacuum phenomena. Factors reaching statistical significance in univariate analyses (P < 0.05) were included in stepwise multiple logistic regression analysis. RESULTS: Degenerative spondylolisthesis (P = 0.004 at L3-4 level and P = 0.017 at L4-5 level in univariate analysis and odds ratio 16.92 at L4-5 level in multiple logistic regression analyses) and spondylolytic spondylolisthesis (P = 0.003 at L5-S1 level in univariate analyses) were the strongest independent determinants of anterior sliding instability. Retrolisthesis (odds ratio 10.97), traction spur (odds ratio 4.45) and spondylarthrosis (odds ratio 3.20) at L3-4 level were statistically significant determinants of posterior sliding instability in multivariate analysis. CONCLUSION: Sliding instability is strongly associated with various plain radiographic findings. In mechanical back pain, functional flexion-extension radiographs should be limited to situations when symptoms are not explained by findings of plain radiographs and/or when they are likely to alter therapy. Pitkaenen, M.T. et al. (2002)

  11. Muscle changes in brachial plexus birth injury with elbow flexion contracture: an MRI study

    International Nuclear Information System (INIS)

    Poeyhiae, Tiina H.; Koivikko, Mika P.; Lamminen, Antti E.; Peltonen, Jari I.; Nietosvaara, A.Y.; Kirjavainen, Mikko O.

    2007-01-01

    Muscle pathology of the arm and forearm in brachial plexus birth injury (BPBI) with elbow flexion contracture has not been evaluated with MRI. To determine whether limited range of motion of the elbow in BPBI is correlated with specific patterns of muscular pathology. For 15 BPBI patients, total active motion (TAM) of the elbow (extension-flexion) and the forearm (pronation-supination) were measured. MRI of the elbow joints and musculature allowed assessment of elbow congruency. Fatty infiltration and size reduction of the muscles were graded semiquantitatively. Mean TAM of the elbow was 113 (50 -140 ) and that of the forearm 91 (10 -165 ). The greater the size reduction of the brachioradialis muscle, the more diminished was elbow TAM. The more extensive the BPBI and muscle pathology of the pronator teres muscle, the more limited was the TAM of the forearm. Pathology of the supinator and brachialis muscles was evident in every patient. Extensive BPBI may result in marked limitation of TAM. Elbow flexion contracture seems to be caused mainly by brachialis muscle pathology. Prosupination of the forearm is better preserved when the pronator teres is not severely affected. MRI can reliably show the extent of muscle pathology in BPBI. (orig.)

  12. Knee flexion with quadriceps cocontraction: A new therapeutic exercise for the early stage of ACL rehabilitation.

    Science.gov (United States)

    Biscarini, Andrea; Contemori, Samuele; Busti, Daniele; Botti, Fabio M; Pettorossi, Vito E

    2016-12-08

    Quadriceps strengthening exercises designed for the early phase of anterior cruciate ligament (ACL) rehabilitation should limit the anterior tibial translation developed by quadriceps contraction near full knee extension, in order to avoid excessive strain on the healing tissue. We hypothesize that knee-flexion exercises with simultaneous voluntary contraction of quadriceps (voluntary quadriceps cocontraction) can yield considerable levels of quadriceps activation while preventing the tibia from translating forward relative to the femur. Electromyographic activity in quadriceps and hamstring muscles was measured in 20 healthy males during isometric knee-flexion exercises executed near full knee extension with maximal voluntary effort of quadriceps cocontraction and external resistance (R) ranging from 0% to 60% of the 1-repetition maximum (1RM). Biomechanical modeling was applied to derive the shear (anterior/posterior) tibiofemoral force developed in each exercise condition. Isometric knee-flexion exercises with small external resistance (R=10% 1RM) and maximal voluntary effort of quadriceps cocontraction yielded a net posterior (ACL-unloading) tibial pull (P=0.005) and levels of activation of 32%, 50%, and 45% of maximum voluntary isometric contraction, for the rectus femoris, vastus medialis, and vastus lateralis, respectively. This exercise might potentially rank as one of the most appropriate quadriceps strengthening interventions in the early phase of ACL rehabilitation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Decoding Finger Flexion From Band-specific ECoG Signals in Humans

    Directory of Open Access Journals (Sweden)

    Nanying eLiang

    2012-06-01

    Full Text Available This article presents the method that won the BCI competition IV addressed to the pre- diction of the finger flexion from ECoG signals. ECoG-based BCIs have recently drawn the attention from the community. Indeed, ECoG can provide a higher spatial resolution, a higher signal quality and is more suitable for long-term use than classical EEG recordings. These characteristics allow to decode precise brain activities and to realize efficient ECoG-based neu- roprostheses. Signal processing is a very important task in BCIs research for translating brain signals into commands. Here, we present a linear regression method based on the amplitude modulation of band-specific ECoG including a short term memory for individual finger flexion prediction. The effectiveness of the method was proven by achieving the highest value of corre- lation coefficient between the predicted and recorded finger flexion values on data set 4 during the BCI competition IV.

  14. Motor unit activation patterns during concentric wrist flexion in humans with different muscle fibre composition.

    Science.gov (United States)

    Søgaard, K; Christensen, H; Fallentin, N; Mizuno, M; Quistorff, B; Sjøgaard, G

    1998-10-01

    Muscle activity was recorded from the flexor carpi radialis muscle during static and dynamic-concentric wrist flexion in six subjects, who had exhibited large differences in histochemically identified muscle fibre composition. Motor unit recruitment patterns were identified by sampling 310 motor units and counting firing rates in pulses per second (pps). During concentric wrist flexion at 30% of maximal exercise intensity the mean firing rate was 27 (SD 13) pps. This was around twice the value of 12 (SD 5) pps recorded during sustained static contraction at 30% of maximal voluntary contraction, despite a larger absolute force level during the static contraction. A similar pattern of higher firing rates during dynamic exercise was seen when concentric wrist flexion at 60% of maximal exercise intensity [30 (SD 14) pps] was compared with sustained static contraction at 60% of maximal voluntary contraction [19 (SD 8) pps]. The increase in dynamic exercise intensity was accomplished by recruitment of additional motor units rather than by increasing the firing rate as during static contractions. No difference in mean firing rates was found among subjects with different muscle fibre composition, who had previously exhibited marked differences in metabolic response during corresponding dynamic contractions. It was concluded that during submaximal dynamic contractions motor unit firing rate cannot be deduced from observations during static contractions and that muscle fibre composition may play a minor role.

  15. Fixed-flexion radiography of the knee provides reproducible joint space width measurements in osteoarthritis

    International Nuclear Information System (INIS)

    Kothari, Manish; Sieffert, Martine; Block, Jon E.; Peterfy, Charles G.; Guermazi, Ali; Ingersleben, Gabriele von; Miaux, Yves; Stevens, Randall

    2004-01-01

    The validity of a non-fluoroscopic fixed-flexion radiographic acquisition and analysis protocol for measurement of joint space width (JSW) in knee osteoarthritis is determined. A cross-sectional study of 165 patients with documented knee osteoarthritis participating in a multicenter, prospective study of chondroprotective agents was performed. All patients had posteroanterior, weight-bearing, fixed-flexion radiography with 10 caudal beam angulation. A specially designed frame (SynaFlexer) was used to standardize the positioning. Minimum medial and lateral JSW were measured manually and twice by an automated analysis system to determine inter-technique and intra-reader concordance and reliability. A random subsample of 30 patients had repeat knee radiographs 2 weeks apart to estimate short-term reproducibility using automated analysis. Concordance between manual and automated medial JSW measurements was high (ICC=0.90); lateral compartment measurements showed somewhat less concordance (ICC=0.72). There was excellent concordance between repeated automated JSW measurements performed 6 months apart for the medial (ICC=0.94) and lateral (ICC=0.86) compartments. Short-term reproducibility for the subsample of 30 cases with repeat acquisitions demonstrated an average SD of 0.14 mm for medial JSW (CV=4.3%) and 0.23 mm for lateral JSW (CV=4.0%). Fixed-flexion radiography of the knee using a positioning device provides consistent, reliable and reproducible measurement of minimum JSW in knee osteoarthritis without the need for concurrent fluoroscopic guidance. (orig.)

  16. Performance Comparison between Neutralization Tailings and Flotation Tailings Used for Backfill Mix and Mechanism Analysis

    Directory of Open Access Journals (Sweden)

    Bin Han

    2016-01-01

    Full Text Available A comparison test of different tailings used for underground backfill was conducted, using neutralized tailings from BIOX and flotation tailings of Jinfeng Mine. Laboratory comparison test results show that, with neutralized tailings, when the cement dosage is at 19%, backfill UCS after 7 days, 14 days, and 28 days are 105%–163%, 80%–102%, and 33%–43%, respectively, which are higher than those of flotation tailings. When the cement dosage is at 12%, backfill UCS after 7 days, 14 days, and 28 days are 58%–77%, 50%–60%, and 28%–51%, respectively, which are higher than those of flotation tailings. Slurry fluidity of neutralized tailings is lower than that of flotation tailings, while, in these two tailings, the difference of slump and diffusivity values is less than 6%, which is not a significant difference in slurry fluidity. The reason for neutralized tailings showing higher UCS is as follows: during backfill curing, neutralization tailings produce abundant crystals of CaSO4·2H2O in interlaced structure which helps in combining aggregates closely; CaSO4·2H2O hydrates with C3A C4AF contained in the cement and forms clavate cement bacillus which works as a micro reinforcing steel bar. The test proved that neutralized tailings are more optimal for backfilling.

  17. Characterization and dewatering of flotation technological tailings

    Directory of Open Access Journals (Sweden)

    Grigorova I.

    2014-01-01

    Full Text Available The treatment of flotation tailings is today a subject of interest in mineral processing because of the potential of wasted materials as an actual mineral resource and because of environmental reasons. Decantation ponds are found at almost every mine in the world. They are large earth fill dams containing the residue of the milling process to extract metals from mined ores. Traditional wet tailings disposal has been problematic due to the risk of ground water contamination and the difficulty in rehabilitating storage sites. Tailings dams are at risk of failure due to leakage, instability, liquefaction, and poor design. In the last few years the use of paste technology in the disposal of mine tailings is increasingly studied as an option to conventional tailings dams. The Lucky Invest Concentrator is located in the Eastern Rhodopes Mountain of Bulgaria. Since 1959 lead-zinc ores are dressed. Finally, during the flotation cycle lead and zinc concentrates are produced. The final technological processing waste precipitates in tailing pond. Research and development program has started to established opportunities to obtain dry deposit of the ore processing residue and analyses the feature of new tailing disposal method. The tailings particle size distributions and chemical compositions were determined. The data from laboratory and pilot scale tests clearly illustrate that there are the possibilities to obtaine lead-zinc dewatered tailings. The experimental results show that new cyclone modifications have a potential in dewatering technology of flotation tailings. It appears that dewatering cyclones can be an approach on new tailings pond elimination technology.

  18. Making the long tail work

    DEFF Research Database (Denmark)

    Thuesen, Christian Langhoff; Jensen, Jens Stissing; Gottlieb, Stefan Christoffer

    2009-01-01

    The paper discusses the development and impact of construction research the past 25 years. Theoretically, the paper builds on two fundamental insights: The Pareto principle (the 80-20 rule) and the Thomas theorem: "If men define situations as real, they are real in their consequences" (Thomas......’s predominant view of buildings – as unique – implies that: 1) the nature of the construction processes is chaotic, 2) the buildings are realised through onsite project work rather than through offsite production; and 3) project management is the fundamental management principle. The paper further identifies...... how attempts to develop new construction practices like partnering and lean implicitly reproduce this myth. The result is that construction research the past 25 years has been constructing the long tail in a way that hinders radical development of the construction industry. The paper concludes...

  19. Profitable tail-end production

    Energy Technology Data Exchange (ETDEWEB)

    Pinchbeck, R.H.

    1997-12-31

    This presentation discusses the origins of the present challenge faced in making mature oil fields profitable in the North Sea. It briefly examines the origins of these challenges, which are rooted in the industrial psychology of the North Sea. It develops a methodological formula for the successful re-engineering of inefficiently-run assets, focusing in particular on the personnel management aspects. It identifies some key areas to seek sustainable cost reductions and recognises the importance of renewing the context for investment in tail-end fields. Finally, it speculates about the way in which the learnings developed in the experiences of the last few years will influence the future of the North Sea. 2 refs.

  20. Disease limits populations: plague and black-tailed prairie dogs

    Science.gov (United States)

    Cully, Jack F.; Johnson, T.; Collinge, S.K.; Ray, C.

    2010-01-01

    Plague is an exotic vector-borne disease caused by the bacterium Yersinia pestis that causes mortality rates approaching 100% in black-tailed prairie dogs (Cynomys ludovicianus). We mapped the perimeter of the active portions of black-tailed prairie dog colonies annually between 1999 and 2005 at four prairie dog colony complexes in areas with a history of plague, as well as at two complexes that were located outside the distribution of plague at the time of mapping and had therefore never been affected by the disease. We hypothesized that the presence of plague would significantly reduce overall black-tailed prairie dog colony area, reduce the sizes of colonies on these landscapes, and increase nearest-neighbor distances between colonies. Within the region historically affected by plague, individual colonies were smaller, nearest-neighbor distances were greater, and the proportion of potential habitat occupied by active prairie dog colonies was smaller than at plague-free sites. Populations that endured plague were composed of fewer large colonies (>100 ha) than populations that were historically plague free. We suggest that these differences among sites in colony size and isolation may slow recolonization after extirpation. At the same time, greater intercolony distances may also reduce intercolony transmission of pathogens. Reduced transmission among smaller and more distant colonies may ultimately enhance long-term prairie dog population persistence in areas where plague is present.

  1. Research on uranium tailings disposal technology at CANMET, Ottawa

    International Nuclear Information System (INIS)

    Skeaff, J.M.; Ritcey, G.M.; Jongejan, A.; Silver, M.

    1982-01-01

    In this paper, results from three continuing investigations at CANMET on uranium tailings management are presented. These investigations are: cleaning of tailings by flotation, conversion of municipal wastes into compost for use as topsoil on uranium tailings, methods for the chemical fixation of uranium tailings and a laboratory determination of the rate of release of environmental contaminants from uranium tailings

  2. Heavy mineral concentration from oil sand tailings

    Energy Technology Data Exchange (ETDEWEB)

    Chachula, F.; Erasmus, N. [Titanium Corp. Inc., Regina, SK (Canada)

    2008-07-01

    This presentation described a unique technique to recover heavy minerals contained in the froth treatment tailings produced by oil sand mining extraction operations in Fort McMurray, Alberta. In an effort to process waste material into valuable products, Titanium Corporation is developing technology to recover heavy minerals, primarily zircon, and a portion of bitumen contained in the final stage of bitumen processing. The process technology is being developed to apply to all mined oil sands operations in the Fort McMurray region. In 2004, Titanium Corporation commissioned a pilot research facility at the Saskatchewan Research Council to test dry oil sands tailings. In 2005, a bulk sampling pilot plant was connected to the fresh oil sands tailings pipeline on-site in Fort McMurray, where washed sands containing heavy minerals were processed at a pilot facility. The mineral content in both deposited tailings and fresh pipeline tailings was assessed. Analysis of fresh tailings on a daily basis identified a constant proportion of zircon and higher levels of associated bitumen compared with the material in the deposited tailings. The process flow sheet design was then modified to remove bitumen from the heavy minerals and concentrate the minerals. A newly modified flotation process was shown to be a viable processing route to recover the heavy minerals from froth treatment tailings. 8 refs., 9 tabs., 12 figs.

  3. Electrodialytic remediation of copper mine tailings

    DEFF Research Database (Denmark)

    Hansen, Henrik K.; Rojo, A.; Ottpsen, Lisbeth M.

    2005-01-01

    electrodialytic remediation experiments on copper mine tailings. The results show that electric current could remove copper from watery tailing if the potential gradient was higher than 2V/cm during 21 days. With addition of sulphuric acid, the process was enhanced because the pH decreased to around 4...

  4. The Netherlands strain of BTV serotype 8 in white-tailed deer

    Science.gov (United States)

    To determine the susceptibility of U.S. white-tailed deer to the European strain of BTV-8 (EU-BTV-8) isolated in The Netherlands, eight seronegative deer were injected subcutaneously in the neck and intradermally in the inner left leg. Two deer were sham inoculated to serve as uninfected controls an...

  5. Performance Comparison between Neutralization Tailings and Flotation Tailings Used for Backfill Mix and Mechanism Analysis

    OpenAIRE

    Han, Bin; Sun, Wei; Yu, Shaofeng; Liu, Chao; Yao, Song; Wu, Jianxun

    2016-01-01

    A comparison test of different tailings used for underground backfill was conducted, using neutralized tailings from BIOX and flotation tailings of Jinfeng Mine. Laboratory comparison test results show that, with neutralized tailings, when the cement dosage is at 19%, backfill UCS after 7 days, 14 days, and 28 days are 105%–163%, 80%–102%, and 33%–43%, respectively, which are higher than those of flotation tailings. When the cement dosage is at 12%, backfill UCS after 7 days, 14 days, and 28 ...

  6. Monte Carlo-based tail exponent estimator

    Science.gov (United States)

    Barunik, Jozef; Vacha, Lukas

    2010-11-01

    In this paper we propose a new approach to estimation of the tail exponent in financial stock markets. We begin the study with the finite sample behavior of the Hill estimator under α-stable distributions. Using large Monte Carlo simulations, we show that the Hill estimator overestimates the true tail exponent and can hardly be used on samples with small length. Utilizing our results, we introduce a Monte Carlo-based method of estimation for the tail exponent. Our proposed method is not sensitive to the choice of tail size and works well also on small data samples. The new estimator also gives unbiased results with symmetrical confidence intervals. Finally, we demonstrate the power of our estimator on the international world stock market indices. On the two separate periods of 2002-2005 and 2006-2009, we estimate the tail exponent.

  7. Analysis of Heavy-Tailed Time Series

    DEFF Research Database (Denmark)

    Xie, Xiaolei

    This thesis is about analysis of heavy-tailed time series. We discuss tail properties of real-world equity return series and investigate the possibility that a single tail index is shared by all return series of actively traded equities in a market. Conditions for this hypothesis to be true...... are identified. We study the eigenvalues and eigenvectors of sample covariance and sample auto-covariance matrices of multivariate heavy-tailed time series, and particularly for time series with very high dimensions. Asymptotic approximations of the eigenvalues and eigenvectors of such matrices are found...... and expressed in terms of the parameters of the dependence structure, among others. Furthermore, we study an importance sampling method for estimating rare-event probabilities of multivariate heavy-tailed time series generated by matrix recursion. We show that the proposed algorithm is efficient in the sense...

  8. Why are most EU pigs tail docked?

    DEFF Research Database (Denmark)

    D'eath, R.B.; Niemi, J.K.; Vosough Ahmadi, B.

    2016-01-01

    To limit tail biting incidence, most pig producers in Europe tail dock their piglets. This is despite EU Council Directive 2008/120/EC banning routine tail docking and allowing it only as a last resort. The paper aims to understand what it takes to fulfil the intentions of the Directive...... by examining economic results of four management and housing scenarios, and by discussing their consequences for animal welfare in the light of legal and ethical considerations. The four scenarios compared are: ‘Standard Docked’, a conventional housing scenario with tail docking meeting the recommendations...... for Danish production (0.7 m2/pig); ‘Standard Undocked’, which is the same as ‘Standard Docked’ but with no tail docking, ‘Efficient Undocked’ and ‘Enhanced Undocked’, which have increased solid floor area (0.9 and 1.0 m2/pig, respectively) provision of loose manipulable materials (100 and 200 g/straw per...

  9. Uranium mill tailings remedial action technology

    International Nuclear Information System (INIS)

    Hartley, J.N.; Gee, G.W.

    1984-01-01

    The uranium milling process involves the hydrometallurgical extraction of uranium from ores and the resultant generation of large quantities of waste referred to as tailings. Uranium mill tailings have been identified as requiring remediation because they contain residual radioactive material that is not removed in the milling process. Potential radiation exposure can result from direct contact with the tailings, from radon gas emitted by the tailings, and from radioactive contamination of groundwater. As a result, the technology developed under the US Department of Energy (DOE) Uranium Mill Tailings Remedial Action Project (UMTRAP) and the US Nuclear Regulatory Commission (NRC) Uranium Recovery Program have focused on radon control, groundwater contamination and the long-term protection of the containment system. This paper briefly summarizes the UMTRAP and NRC remedial action technology development. 33 references, 9 figures, 5 tables

  10. The effect of prior lumbar surgeries on the flexion relaxation phenomenon and its responsiveness to rehabilitative treatment.

    Science.gov (United States)

    Neblett, Randy; Mayer, Tom G; Brede, Emily; Gatchel, Robert J

    2014-06-01

    Abnormal pretreatment flexion-relaxation in chronic disabling occupational lumbar spinal disorder patients has been shown to improve with functional restoration rehabilitation. Little is known about the effects of prior lumbar surgeries on flexion-relaxation and its responsiveness to treatment. To quantify the effect of prior lumbar surgeries on the flexion-relaxation phenomenon and its responsiveness to rehabilitative treatment. A prospective cohort study of chronic disabling occupational lumbar spinal disorder patients, including those with and without prior lumbar spinal surgeries. A sample of 126 chronic disabling occupational lumbar spinal disorder patients with prior work-related injuries entered an interdisciplinary functional restoration program and agreed to enroll in this study. Fifty-seven patients had undergone surgical decompression or discectomy (n=32) or lumbar fusion (n=25), and the rest had no history of prior injury-related spine surgery (n=69). At post-treatment, 116 patients were reevaluated, including those with prior decompressions or discectomies (n=30), lumbar fusions (n=21), and no surgery (n=65). A comparison group of 30 pain-free control subjects was tested with an identical assessment protocol, and compared with post-rehabilitation outcomes. Mean surface electromyography (SEMG) at maximum voluntary flexion; subject achievement of flexion-relaxation (SEMG≤3.5 μV); gross lumbar, true lumbar, and pelvic flexion ROM; and a pain visual analog scale self-report during forward bending task. Identical measures were obtained at pretreatment and post-treatment. Patients entered an interdisciplinary functional restoration program, including a quantitatively directed, medically supervised exercise process and a multimodal psychosocial disability management component. The functional restoration program was accompanied by a SEMG-assisted stretching training program, designed to teach relaxation of the lumbar musculature during end-range flexion

  11. Molecular analysis of the bacterial diversity in uranium mill tailings

    International Nuclear Information System (INIS)

    Geissler, A.

    2003-04-01

    A culture-independent molecular approach has been applied to investigate the bacterial diversity in three uranium contaminated sites. The three analysed soil samples have been collected from the uranium waste pile Haberland near Johanngeorgenstadt (Germany), from the uranium mill tailings in Gunnison, Colorado (USA) and from the uranium mill tailings in Shiprock, New Mexico (USA). The 16S rDNA fragments which has been isolated through direct lysis of the whole-DNA were amplified by the use of the universal primers 16S 43f and 16S 1404r and cloned. With restriction fragment length polymorphismus (RFLP) were the clones screened and one representative of all RFLP types that occurred more than once in the clone library was sequenced and analysed. In spite of the contamination a considerable diversity and significant differences in the composition of the natural bacterial communities in these three sites have been found. In the sample collected from the waste pile Haberland near Johanngeorgenstadt α-Proteobacteria and representatives of the Holophaga/Acidobacterium were numerically predominant. The distribution of bacteria in the sample collected from uranium mill tailings Gunnison was very similar to those found in the Haberland waste pile, but there were found besides α-Proteobacteria and representatives of Holophaga/Acidobacterium a lot of γ-Proteobacteria. The structure of the bacterial community in the sample collected from the uranium mill tailings Shiprock was significantly different. Only some representatives of the Holophaga/Acidobacterium and α-Proteobacteria were represented. Large populations of Bacilli, γ-Proteobacteria and green non sulfur bacteria were dominant in this sample. (orig.)

  12. Tail posture predicts tail biting outbreaks at pen level in weaner pigs

    DEFF Research Database (Denmark)

    Lahrmann, Helle Pelant; Hansen, Christian Fink; D'Eath, Rick

    2018-01-01

    posture and behaviour could be detected at pen level between upcoming tail biting pens (T-pens) and control pens (C-pens). The study included 2301 undocked weaner pigs in 74 pens (mean 31.1 pigs/pen; SD 1.5). Tails were scored three times weekly (wound freshness, wound severity and tail length) between 07......Detecting a tail biting outbreak early is essential to reduce the risk of pigs getting severe tail damage. A few previous studies suggest that tail posture and behavioural differences can predict an upcoming outbreak. The aim of the present study was therefore to investigate if differences in tail......:00 h-14:00 h from weaning until a tail biting outbreak. An outbreak (day 0) occurred when at least four pigs had a tail damage, regardless of wound freshness. On average 7.6 (SD 4.3) pigs had a damaged tail (scratches + wound) in T-pens on day 0. Tail posture and behaviour (activity, eating...

  13. Effects of various tailings covers on radon gas emanation from pyritic uranium tailings

    International Nuclear Information System (INIS)

    Dave, N.K.; Lim, T.P.

    1987-01-01

    Radon emanation studies were carried out at an inactive pyritic uranium tailings site in Elliot Lake, Ontario, Canada, to evaluate the effects of various existing dry and wet covers on radon flux rates. Measurements were taken using activated charcoal cartridges for various surface covers consisting of bare, vegetated, acidophilic moss with high degree of water saturation, compacted crushed rock and gravel, and winter snow. The results showed that at a given site, there was no significant difference in radon emanation rates between various tailings covers and bare tailings. In particular, no increase In radon emanation rates from vegetated areas compared to bare tailings was observed. Radon emanation rates varied spatially depending on tailings grain size, porosity, moisture content and on pressure and water table variations. The emanation rates were higher for tailings with low water contents compared to those for wet and moss covered tailings

  14. Knee Flexion and Daily Activities in Patients following Total Knee Replacement: A Comparison with ISO Standard 14243

    Directory of Open Access Journals (Sweden)

    Markus A. Wimmer

    2015-01-01

    Full Text Available Walking is only one of many daily activities performed by patients following total knee replacement (TKR. The purpose of this study was to examine the hypotheses (a that subject activity characteristics are correlated with knee flexion range of motion (ROM and (b that there is a significant difference between the subject’s flexion/extension excursion throughout the day and the ISO specified input for knee wear testing. In order to characterize activity, the number of walking and stair stepping cycles, the time spent with dynamic and stationary activities, the number of activity sequences, and the knee flexion/extension excursion of 32 TKR subjects were collected during daily activity. Flexion/extension profiles were compared with the ISO 14243 simulator input profile using a level crossing classification algorithm. Subjects took an average of 3102 (range: 343–5857 walking cycles including 65 (range: 0–319 stair stepping cycles. Active and passive ROMs were positively correlated with stair walking time, stair step counts, and stair walking sequences. Simulated knee motion according to ISO showed significantly fewer level crossings at the flexion angles 20–40° and beyond 50° than those measured with the monitor. This suggests that implant wear testing protocols should contain more cycles and a variety of activities requiring higher knee flexion angles with incorporated resting/transition periods to account for the many activity sequences.

  15. The importance of bony impingement in restricting flexion after total knee arthroplasty: computer simulation model with clinical correlation.

    Science.gov (United States)

    Mizu-Uchi, Hideki; Colwell, Clifford W; Fukagawa, Shingo; Matsuda, Shuichi; Iwamoto, Yukihide; D'Lima, Darryl D

    2012-10-01

    We constructed patient-specific models from computed tomography data after total knee arthroplasty to predict knee flexion based on implant-bone impingement. The maximum flexion before impingement between the femur and the tibial insert was computed using a musculoskeletal modeling program (KneeSIM; LifeModeler, Inc, San Clemente, California) during a weight-bearing deep knee bend. Postoperative flexion was measured in a clinical cohort of 21 knees (low-flex group: 6 knees with 125° of flexion at 2 years). Average predicted flexion angles were within 2° of clinical measurements for the high-flex group. In the low-flex group, 4 cases had impingement involving the bone cut at the posterior condyle, and the average predicted knee flexion was 102° compared with 93° measured clinically. These results indicate that the level of the distal femoral resection should be carefully planned and that exposed bone proximal to the tips of the posterior condyles of the femoral component should be removed if there is risk of impingement. Copyright © 2012 Elsevier Inc. All rights reserved.

  16. Asymmetric Extreme Tails and Prospective Utility of Momentum Returns

    NARCIS (Netherlands)

    Stork, P.A.; Gregory-Allen, R.; Lu, H.

    2012-01-01

    We use extreme value theory to analyse the tails of a momentum strategy's return distribution. The asymmetry between the fat left tail and thin right tail strongly reduces a momentum strategy's prospective utility levels. © 2012 Elsevier B.V.

  17. Engineering assessment of inactive uranium mill tailings, Shiprock site, Shiprock, New Mexico. Phase II, Title I

    International Nuclear Information System (INIS)

    1977-01-01

    Ford, Bacon and Davis Utah Inc. has performed an engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Shiprock, New Mexico. The Phase II, Title I services include the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and other radium-contaminated materials, the evaluation of resulting radiation exposures of individuals and nearby populations, the investigation of site hydrology and meteorology and the evaluation and costing of alternative corrective actions. Radon gas release from the 1.7 million tons of tailings at the Shiprock site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation are also factors. The 11 alternative actions presented range from completion of the present ongoing EPA site decontamination plan (Option I), to stabilizing in-place with varying depths of cover material (Options II-IV), to removal to an isolated long-term disposal site (Options V-XI). All options include remedial action costs for off-site locations where tailings have been placed. Costs estimates for the 11 options range from $540,000 to $12,500,000. Reprocessing the tailings for uranium is not economically feasible

  18. Engineering assessment of inactive uranium mill tailings, Shiprock site, Shiprock, New Mexico. Phase II, Title I

    Energy Technology Data Exchange (ETDEWEB)

    1977-03-31

    Ford, Bacon and Davis Utah Inc. has performed an engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Shiprock, New Mexico. The Phase II, Title I services include the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and other radium-contaminated materials, the evaluation of resulting radiation exposures of individuals and nearby populations, the investigation of site hydrology and meteorology and the evaluation and costing of alternative corrective actions. Radon gas release from the 1.7 million tons of tailings at the Shiprock site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation are also factors. The 11 alternative actions presented range from completion of the present ongoing EPA site decontamination plan (Option I), to stabilizing in-place with varying depths of cover material (Options II-IV), to removal to an isolated long-term disposal site (Options V-XI). All options include remedial action costs for off-site locations where tailings have been placed. Costs estimates for the 11 options range from $540,000 to $12,500,000. Reprocessing the tailings for uranium is not economically feasible.

  19. Engineering assessment of inactive uranium mill tailings, Durango site, Durango, Colorado. Phase II, Title I

    International Nuclear Information System (INIS)

    1977-11-01

    Ford, Bacon and Davis Utah Inc. has performed an engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Durango, Colorado. The Phase II, Title I services include the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and other radium-contaminated materials, the evaluation of resulting radiation exposures of individuals and nearby populations, the investigation of site hydrology and meteorology and the evaluation and costing of alternative corrective actions. Radon gas release from the 1.555 million tons of tailings at the Durango site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation are also factors. The eight alternative actions presented range from vegetative stabilization (Option I), to contouring and stabilizing in-place with varying depths of cover material (Options II and III), to removal to an isolated long-term disposal site (Options V to VIII). All options include remedial action costs for offsite locations where tailings have been placed. Costs estimated for the eight options range from $4,340,000 to $13,590,000. Reprocessing the tailings for uranium is sufficiently economically attractive to justify reprocessing in conjunction with each of the options

  20. Phytoremediation of Alberta oil sand tailings using native plants and fungal endophytes

    Science.gov (United States)

    Repas, T.; Germida, J.; Kaminskyj, S.

    2012-04-01

    Fungal endophytes colonize host plants without causing disease. Some endophytes confer plant tolerance to harsh environments. One such endophyte, Trichoderma harzianum strain TSTh20-1, was isolated from a plant growing on Athabasca oil sand tailings. Tailing sands are a high volume waste product from oil sand extraction that the industry is required to remediate. Tailing sands are low in organic carbon and mineral nutrients, and are hydrophobic due to residual polyaromatic hydrocarbons. Typically, tailing sands are remediated by planting young trees in large quantities of mulch plus mineral fertilizer, which is costly and labour intensive. In greenhouse trials, TSTh20-1 supports growth of tomato seedlings on tailing sands without fertilizer. The potential use of TSTh20-1 in combination with native grasses and forbs to remediate under field conditions is being assessed. Twenty-three commercially available plant species are being screened for seed germination and growth on tailing sands in the presence of TSTh20-1. The best candidates from this group will be used in greenhouse and small scale field trials. Potential mechanisms that contribute to endophyte-induced plant growth promotion, such as plant hormone production, stress tolerance, mineral solubilization, and uptake are also being assessed. As well, TSTh20-1 appears to be remarkably frugal in its nutrient requirements and the possibility that this attribute is characteristic of other plant-fungal endophytes from harsh environments is under study.

  1. Gecko CD59 Is Implicated in Proximodistal Identity during Tail Regeneration

    Science.gov (United States)

    Jiang, Shengjuan; Zhou, Weijuan; Liu, Yan; Wang, Yingjie; Gu, Qing; Gu, Yun; Dong, Yingying; Liu, Mei; Gu, Xingxing; Ding, Fei; Gu, Xiaosong

    2011-01-01

    Several adult reptiles, such as Gekko japonicus, have the ability to precisely re-create a missing tail after amputation. To ascertain the associated acquisition of positional information from blastemal cells and the underlying molecular mechanism of tail regeneration, a candidate molecule CD59 was isolated from gecko. CD59 transcripts displayed a graded expression in the adult gecko spinal cord with the highest level in the anterior segment, with a stable expression along the normal tail. After tail amputation, CD59 transcripts in the spinal cord proximal to the injury sites increased markedly at 1 day and 2 weeks; whereas in the regenerating blastema, strong CD59 positive signals were detected in the blastemal cells anterior to the blastema, with a gradual decrease along the proximodistal (PD) axis. When treated with RA following amputation, CD59 transcripts in the blastema were up-regulated. PD confrontation assays revealed that the proximal blastema engulfed the distal one after in vitro culture, and rabbit-anti human CD59 antibody was able to block this PD engulfment. Overexpression of the CD59 during tail regeneration causes distal blastemal cells to translocate to a more proximal location. Our results suggest that position identity is not restricted to amphibian limb regeneration, but has already been established in tail blastema of reptiles. The CD59, a cell surface molecule, acted as a determinant of proximal–distal cell identity. PMID:21464923

  2. Design, permitting, and construction issues associated with closure of the Panna Maria uranium tailings impoundment

    International Nuclear Information System (INIS)

    Strachan, C.L.; Raabe, K.L.

    1997-01-01

    In 1992, Panna Maria Uranium Operations (PMUO) initiated licensing and engineering activities for closure of the Panna Maria mill and 150-acre tailings impoundment located in southeast Texas. Closure of the tailings impoundment is permitted by license amendment through the Texas Natural Resources Conservation Commission (TNRCC), and based on closure criteria outlined in Texas regulations. The closure plan for the Panna Maria tailings impoundment was submitted for Texas regulatory agency review in April 1993, with details of the closure plan modified in 1994, 1995, and 1996. The closure plan included a multi-layered cover over the regraded tailings surface which was designed for long-term isolation of tailings, reduction of radon emanation to regulated levels, and reduction of infiltration to TNRCC-accepted levels. The cover and embankment slope surfaces and surrounding areas were designed to provide acceptable erosional stability as compared to runoff velocities from the Probable Maximum Precipitation event. Cover materials were selected from on-site materials and evaluated for suitability based on permeability, radon attenuation, and soil dispersivity characteristics. Off-site materials were used when necessary. The cover over the tailings has a maximum slope of 0.5 percent, and the regraded embankment slopes outside the perimeter of the impoundment have a maximum slope of 20 percent. All reclaimed slopes are covered with topsoil and revegetated. A riprap-lined channel is to be used to convey runoff from within the perimeter of the reclaimed impoundment to the north of the impoundment

  3. Intrusion of soil covered uranium mill tailings by whitetail prairie dogs and Richardson's ground squirrels

    International Nuclear Information System (INIS)

    Shuman, R.

    1984-01-01

    The primary objective of the reclamation of uranium mill tailings is the long-term isolation of the matrial from the biosphere. Fossorial and semi-fossorial species represent a potentially disruptive influence as a result of their burrowing habits. The potential for intrusion was investigated with respect to two sciurids, the whitetail prairie dog (Cynomys leucurus) and Richardson's ground squirrel (Spermophilus richardsonii). Populations of prairie dogs were established on a control area, lacking a tailings layer, and two experimental areas, underlain by a waste layer, in southeastern Wyoming. Weekly measurements of prairie dog mound surface activities were conducted to demonstrate penetration, or lack thereof, of the tailings layer. Additionally, the impact of burrowing upon radon flux was determined. Limited penetration of the waste layer was noted after which frequency of inhabitance of the intruding burrow system declined. No significant changes in radon flux were detected. In another experiment, it was found that Richardson's ground squirrels burrowed to less extreme depths when confronted by mill tailings. Additional work at an inactive tailings pile in western Colorado revealed repeated intrusion through a shallow cover, and subsequent transport of radioactive material to the ground surface by prairie dogs. Radon flux from burrow entrances was significantly greater than that from undisturbed ground. Data suggested that textural and pH properties of tailings material may act to discourage repeated intrusion at some sites. 58 references

  4. Phylogenetic and pathogenic characterization of novel adenoviruses from long-tailed ducks (Clangula hyemalis)

    Science.gov (United States)

    Counihan, Katrina; Skerratt, Lee; Franson, J. Christian; Hollmen, Tuula E.

    2015-01-01

    Novel adenoviruses were isolated from a long-tailed duck (Clangula hyemalis) mortality event near Prudhoe Bay, Alaska in 2000. The long-tailed duck adenovirus genome was approximately 27 kb. A 907 bp hexon gene segment was used to design primers specific for the long-tailed duck adenovirus. Nineteen isolates were phylogenetically characterized based on portions of their hexon gene and 12 were most closely related to Goose adenovirus A. The remaining 7 shared no hexon sequences with any known adenoviruses. Experimental infections of mallards with a long-tailed duck reference adenovirus caused mild lymphoid infiltration of the intestine and paint brush hemorrhages of the mucosa and dilation of the intestine. This study shows novel adenoviruses from long-tailed ducks are diverse and provides further evidence that they should be considered in cases of morbidity and mortality in sea ducks. Conserved and specific primers have been developed that will help screen sea ducks for adenoviral infections.

  5. Basic description of tailings from Aitik focusing on mechanical behavior

    OpenAIRE

    Bhanbhro, Riaz; Knutsson, Roger; Rodriguez, Juan; Edeskär, Tommy; Knutsson, Sven

    2013-01-01

    Tailings are artificial granular materials that behave different as compared to natural soil of equal grain sizes. Tailings particle sizes, shapes, gradation and mechanical behavior may influence the performance of tailings dams. Hence it is essential to understand the tailings materials in depth. This article describes present studies being carried out on Aitik tailings. Basic tailings characteristics including specific gravity, phase relationships, particle sizes, particle shapes and direct...

  6. Ilmenite Mineral's Recovery from Beach Sand Tailings

    International Nuclear Information System (INIS)

    Mulaba-Bafubiandi, Antoine F.; Mukendi-Ngalula, David; Waanders, Frans B.

    2002-01-01

    The mineral ilmenite is the major source of rutile for industrial use and is of interest to paint and fertiliser industries. Enormous unutilised tailing dams lie on the eastern coast of the South Africa. Although covered by a simulation of the original indigenous vegetation, these tailings are still ilmenite bearing and of economic value. Tailings emanating from beach sand mineral slimes dams of the Kwazulu-Natal area (South Africa) have been processed. Screening, flotation, spiral concentration and magnetic separation methods were used either separately or successively. The present work sheds light on alternative routes for the extraction of the ilmenite, from these tailings. It moreover points out the usefulness of the Moessbauer spectroscopy in the mineral processing product monitoring. Tailings from the beach sands were used in the present study after the economic industrial minerals zirconia, ilmenite and rutile had been extracted in previous mining operations. About 61% natural ilmenite recovery was observed in the flotation concentrate of a Humphrey Spiral concentrate while a 62% recovery of hematite was found in the flotation tailings. The combination of screening, spiral concentration and magnetic separation, and flotation yielded a product with the highest ilmenite and hematite concentration being 71% and 19%, respectively. A natural ilmenite mineral, containing 87% ilmenite and 13% hematite, could be produced and extracted from the tailings of the flotation process, collected subsequently to the spiral concentration and the initial screening.

  7. The evolution of tail weaponization in amniotes.

    Science.gov (United States)

    Arbour, Victoria M; Zanno, Lindsay E

    2018-01-31

    Weaponry, for the purpose of intraspecific combat or predator defence, is one of the most widespread animal adaptations, yet the selective pressures and constraints governing its phenotypic diversity and skeletal regionalization are not well understood. Here, we investigate the evolution of tail weaponry in amniotes, a rare form of weaponry that nonetheless evolved independently among a broad spectrum of life including mammals, turtles and dinosaurs. Using phylogenetic comparative methods, we test for links between morphology, ecology and behaviour in extant amniotes known to use the tail as a weapon, and in extinct taxa bearing osseous tail armaments. We find robust ecological and morphological correlates of both tail lashing behaviour and bony tail weaponry, including large body size, body armour and herbivory, suggesting these life-history parameters factor into the evolution of antipredator behaviours and tail armaments. We suggest that the evolution of tail weaponry is rare because large, armoured herbivores are uncommon in extant terrestrial faunas, as they have been throughout evolutionary history. © 2018 The Author(s).

  8. APPLICATION OF POSTFLOTATION TAILINGS IN HYDROENGINEERING STRUCTURES

    Directory of Open Access Journals (Sweden)

    Katarzyna Stefaniak

    2017-01-01

    Full Text Available Economic development stimulated by the increased demand for production of consumer goods and the growing human population result in increasing amounts of various wastes, including tailings. The mining industry in Poland, comprising also mining of non-ferrous metal ores, is a strategic branch of the national economy and at the same time a leading waste producer. Tailings management is a significant problem both in Poland and worldwide. Frequently considerable amounts of wastes are accumulated in mine spoil tips, in areas not always suitable for their deposition, thus leading to the degradation of the surrounding environment. At the huge volume of produced wastes their rational and economically viable management is becoming crucial. On the other hand, depletion of natural aggregate deposits is an important incentive to search for substitutes, which would be suitable for the development of road infrastructure or which could be used in earth structure engineering to construct hydroengineering objects. Since no profitable recovery technologies are available at present, tailings generated by copper mining are deposited in tailings storage facilities. The largest and at the same time the only currently operating facility in Poland is the Żelazny Most Mining Tailings Storage Facility, belonging to KGHM Polska Miedź S.A. The paper presents criteria for material quality and density imposed on the material embedded in the static core of the tailings pond dam. For this purpose studies were conducted to confirm applicability of sorted tailings as a material for the construction of earth structures.

  9. Engineering assessment of inactive uranium mill tailings

    International Nuclear Information System (INIS)

    1981-07-01

    The Grand Junction site has been reevaluated in order to revise the October 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Grand Junction, Colorado. This engineering assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposures of individuals and nearby populations, the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the 1.9 million tons of tailings at the Grand Junction site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation are also factors. The eight alternative actions presented herein range from millsite and off-site decontamination with the addition of 3 m of stabilization cover material (Option I), to removal of the tailings to remote disposal sites and decontamination of the tailings site (Options II through VIII). Cost estimates for the eight options range from about $10,200,000 for stabilization in-place to about $39,500,000 for disposal in the DeBeque area, at a distance of about 35 mi, using transportation by rail. If transportation to DeBeque were by truck, the cost estimated to be about $41,900,000. Three principal alternatives for the reprocessing of the Grand Junction tailings were examined: (a) heap leaching; (b) treatment at an existing mill; and (c) reprocessing at a new conventional mill constructed for tailings reprocessing. The cost of the uranium recovered would be about $200/lb by heap leach and $150/lb by conventional plant processes. The spot market price for uranium was $25/lb early in 1981. Therefore, reprocessing the tailings for uranium recovery appears not to be economically attractive

  10. Engineering assessment of inactive uranium mill tailings

    Energy Technology Data Exchange (ETDEWEB)

    1981-07-01

    The Grand Junction site has been reevaluated in order to revise the October 1977 engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Grand Junction, Colorado. This engineering assessment has included the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and radiation exposures of individuals and nearby populations, the investigations of site hydrology and meteorology, and the evaluation and costing of alternative corrective actions. Radon gas released from the 1.9 million tons of tailings at the Grand Junction site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation are also factors. The eight alternative actions presented herein range from millsite and off-site decontamination with the addition of 3 m of stabilization cover material (Option I), to removal of the tailings to remote disposal sites and decontamination of the tailings site (Options II through VIII). Cost estimates for the eight options range from about $10,200,000 for stabilization in-place to about $39,500,000 for disposal in the DeBeque area, at a distance of about 35 mi, using transportation by rail. If transportation to DeBeque were by truck, the cost estimated to be about $41,900,000. Three principal alternatives for the reprocessing of the Grand Junction tailings were examined: (a) heap leaching; (b) treatment at an existing mill; and (c) reprocessing at a new conventional mill constructed for tailings reprocessing. The cost of the uranium recovered would be about $200/lb by heap leach and $150/lb by conventional plant processes. The spot market price for uranium was $25/lb early in 1981. Therefore, reprocessing the tailings for uranium recovery appears not to be economically attractive.

  11. ANALYSIS OF ISOKINETIC KNEE EXTENSION / FLEXION IN MALE ELITE ADOLESCENT WRESTLERS

    Directory of Open Access Journals (Sweden)

    Sanli Sadi Kurdak

    2005-12-01

    Full Text Available Wrestling requires strength of the upper and lower body musculature which is critical for the athletic performance. Evaluation of the adolescent's skeletal muscle is important to understand body movement, especially including those involved in sports. Strength, power and endurance capacity are defined as parameters of skeletal muscle biomechanical properties. The isokinetic dynamometer is an important toll for making this type of evaluation. However, load range phase of range of motion has to be considered to interpret the data correctly. With this in mind we aimed to investigate the lover body musculature contractile characteristics of adolescent wrestlers together with detailed analyses of load range phase of motion. Thirteen boys aged 12 - 14 years participated to this study. Concentric load range torque, work and power of knee extension and flexion were measured by a Cybex Norm dynamometer at angular velocities from 450°/sec to 30°/sec with 30°/sec decrements for each set. None of the wrestlers were able to attain load range for angular velocities above 390°/sec and 420°/sec for extension and flexion respectively. Detailed analyses of the load range resulted in statistically significant differences in the normalized load range peak torque for extension at 270°/sec (1.44 ± 0.28 Nm·kg-1 and 1.14 ± 0.28 Nm·kg-1 for total and load range peak torque respectively, p < 0.05, and for flexion at 300°/sec (1.26 ± 0.28 Nm·kg-1 and 1.03 ± 0.23 Nm·kg-1 for total and load range peak torque respectively, p < 0.05, compared to total peak torque data. Similarly, the significant difference was found for the work values at 90°/sec (1.91 ± 0.23 Nm·kg-1 and 1.59 ± 0.24 Nm·kg-1 for total and load range work respectively for extension and 1.73 ± 0.21 Nm·kg-1 and 1.49 ± 0.19 Nm·kg-1 for total and load range work respectively for flexion, p < 0.05, and was evident at higher angular velocities (p < 0.001 for both extension and flexion. At

  12. Cameco engineered tailings program: linking research with industrial processes for improved tailings performance

    International Nuclear Information System (INIS)

    Kotzer, T.; Hendry, M.J.

    2011-01-01

    The waste product from uranium mining and milling that generates the greatest public and regulatory concern is tailings. The tailings contain all of the mined material except uranium plus a host of processing reagents. These minerals and compounds have the potential to harm the local environment if not deposited in a fashion that is both geochemically and geotechnically stable. Environmental leadership impels Cameco Corporation to ensure that the methods used to dispose of tailings are at the forefront of best available technologies whereby tailings production results in a product with geotechnical and geochemical characteristics that minimize the environmental impact associated with long-term storage of this product. Cameco has developed an Engineered Tailings (ET) program to ensure optimization of long-term tailings performance and minimal impacts of elements of concern (EOCs) to the receiving environment, regardless of the ore being milled. Within this program chemical and physical performance of tailings from geochemical and geotechnical investigations and baseline environmental data, integrated with regulatory requirements and corporate commitments, will be used to evaluate and set criteria for mill- and tailings management facilities-based chemical and physical tailings characteristics, identify key knowledge gaps, prioritize areas of concern and implement appropriate responses. This paper provides an overview of the Engineered Tailings program, the research being conducted as part of the ET program, and how it links with present and future Cameco operations. (author)

  13. A successful backward step correlates with hip flexion moment of supporting limb in elderly people.

    Science.gov (United States)

    Takeuchi, Yahiko

    2018-01-01

    The objective of this study was to determine the positional relationship between the center of mass (COM) and the center of pressure (COP) at the time of step landing, and to examine their relationship with the joint moments exerted by the supporting limb, with regard to factors of the successful backward step response. The study population comprised 8 community-dwelling elderly people that were observed to take successive multi steps after the landing of a backward stepping. Using a motion capture system and force plate, we measured the COM, COP and COM-COP deviation distance on landing during backward stepping. In addition, we measured the moment of the supporting limb joint during backward stepping. The multi-step data were compared with data from instances when only one step was taken (single-step). Variables that differed significantly between the single- and multi-step data were used as objective variables and the joint moments of the supporting limb were used as explanatory variables in single regression analyses. The COM-COP deviation in the anteroposterior was significantly larger in the single-step. A regression analysis with COM-COP deviation as the objective variable obtained a significant regression equation in the hip flexion moment (R2 = 0.74). The hip flexion moment of supporting limb was shown to be a significant explanatory variable in both the PS and SS phases for the relationship with COM-COP distance. This study found that to create an appropriate backward step response after an external disturbance (i.e. the ability to stop after 1 step), posterior braking of the COM by a hip flexion moment are important during the single-limbed standing phase.

  14. Trunk Muscle Activation at the Initiation and Braking of Bilateral Shoulder Flexion Movements of Different Amplitudes.

    Directory of Open Access Journals (Sweden)

    M Eriksson Crommert

    Full Text Available The aim of this study was to investigate if trunk muscle activation patterns during rapid bilateral shoulder flexions are affected by movement amplitude. Eleven healthy males performed shoulder flexion movements starting from a position with arms along sides (0° to either 45°, 90° or 180°. EMG was measured bilaterally from transversus abdominis (TrA, obliquus internus (OI with intra-muscular electrodes, and from rectus abdominis (RA, erector spinae (ES and deltoideus with surface electrodes. 3D kinematics was recorded and inverse dynamics was used to calculate the reactive linear forces and torque about the shoulders and the linear and angular impulses. The sequencing of trunk muscle onsets at the initiation of arm movements was the same across movement amplitudes with ES as the first muscle activated, followed by TrA, RA and OI. All arm movements induced a flexion angular impulse about the shoulders during acceleration that was reversed during deceleration. Increased movement amplitude led to shortened onset latencies of the abdominal muscles and increased level of activation in TrA and ES. The activation magnitude of TrA was similar in acceleration and deceleration where the other muscles were specific to acceleration or deceleration. The findings show that arm movements need to be standardized when used as a method to evaluate trunk muscle activation patterns and that inclusion of the deceleration of the arms in the analysis allow the study of the relationship between trunk muscle activation and direction of perturbing torque during one and the same arm movement.

  15. Pneumatic Multi-Pocket Elastomer Actuators for Metacarpophalangeal Joint Flexion and Abduction-Adduction

    Directory of Open Access Journals (Sweden)

    Tapio Veli Juhani Tarvainen

    2017-09-01

    Full Text Available During recent years, interest has been rising towards developing fluidic fiber-reinforced elastomer actuators for wearable soft robotics used in hand rehabilitation and power-assist. However, they do not enable finger abduction-adduction, which plays an important role in activities of daily living, when grasping larger objects. Furthermore, the developed gloves often do not have separate control of joints, which is important for doing various common rehabilitation motions. The main obstacle for the development of a fully-assisting glove is moving a joint with multiple degrees of freedom. If the functions are built into the same structure, they are naturally coupled and affect each other, which makes them more difficult to design and complex to control than a simple flexion-extension actuator. In this study, we explored the key design elements and fabrication of pneumatic multi-pocket elastomer actuators for a soft rehabilitation glove. The goal was to gain more control over the metacarpophalangeal joint’s response by increasing the degree of actuation. Three main functional designs were tested for achieving both flexion and abduction-adduction. Five prototypes, with four different actuator geometries and four different reinforcement types, were designed and fabricated. They were evaluated by recording their free motion with motion capture and measuring their torque output using a dummy finger. Results showed the strengths and weaknesses of each design in separating the control of the two functions. We discuss the different improvements that are needed in order to make each design plausible for developing an actuator that meets the requirements for full assist of the hand’s motions. In conclusion, we show that it is possible to produce multi-pocket actuators for assisting MCP joint motion in both flexion and abduction-adduction, although coupling between the separate functions is still problematic and should be considered further.

  16. Effects of a 16-week Pilates exercises training program for isometric trunk extension and flexion strength.

    Science.gov (United States)

    Kliziene, Irina; Sipaviciene, Saule; Vilkiene, Jovita; Astrauskiene, Audrone; Cibulskas, Gintautas; Klizas, Sarunas; Cizauskas, Ginas

    2017-01-01

    To evaluate the effects of Pilates exercises designed to improve isometric trunk extension and flexion strength of muscles in women with chronic low back pain (cLBP). Female volunteers with cLBP were divided into an experimental group (EG; n = 27) and a control group (CG; n = 27). Pilates exercises were performed twice per week by the EG; the duration of each session was 60 min. The program lasted for 16 weeks; thus patients underwent a total of 32 exercise sessions. The maximum isometric waist bending strength of the EG had improved significantly (p = 0.001) after 16 weeks of the Pilates program. The results of trunk flexion muscle endurance tests significantly depended on the trunk extension muscle endurance before the intervention, and at 1 month (r = 0.723, p Pilates exercise program. At the end of the 16-week exercise program, cLBP intensity decreased by 2.01 ± 0.8 (p Pilates exercise program the pain intensified and the functional state deteriorated much faster than the maximum trunk muscle strength. Therefore, it can be concluded that, to decrease pain and improve functional condition, regular exercise (and not only improved strength and endurance) is required. We established that, although the 16-week lumbar stabilization exercise program increased isometric trunk extension and flexion strength and this increase in strength persisted for 2 months, decreased LBP and improved functional condition endured for only 1 month. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Measurement properties of the craniocervical flexion test: a systematic review protocol.

    Science.gov (United States)

    Araujo, Francisco Xavier de; Ferreira, Giovanni Esteves; Scholl Schell, Maurício; Castro, Marcelo Peduzzi de; Silva, Marcelo Faria; Ribeiro, Daniel Cury

    2018-02-22

    Neck pain is the leading cause of years lived with disability worldwide and it accounts for high economic and societal burden. Altered activation of the neck muscles is a common musculoskeletal impairment presented by patients with neck pain. The craniocervical flexion test with pressure biofeedback unit has been widely used in clinical practice to assess function of deep neck flexor muscles. This systematic review will assess the measurement properties of the craniocervical flexion test for assessing deep cervical flexor muscles. This is a protocol for a systematic review that will follow the Preferred Reporting Items for Systematic Review and Meta-Analysis statement. MEDLINE (via PubMed), EMBASE, PEDro, Cochrane Central Register of Controlled Trials (CENTRAL), Scopus and Science Direct will be systematically searched from inception. Studies of any design that have investigated and reported at least one measurement property of the craniocervical flexion test for assessing the deep cervical flexor muscles will be included. All measurement properties will be considered as outcomes. Two reviewers will independently rate the risk of bias of individual studies using the updated COnsensus-based Standards for the selection of health Measurement Instruments risk of bias checklist. A structured narrative synthesis will be used for data analysis. Quantitative findings for each measurement property will be summarised. The overall rating for a measurement property will be classified as 'positive', 'indeterminate' or 'negative'. The overall rating will be accompanied with a level of evidence. Ethical approval and patient consent are not required since this is a systematic review based on published studies. Findings will be submitted to a peer-reviewed journal for publication. CRD42017062175. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  18. Increasing trunk flexion transforms human leg function into that of birds despite different leg morphology.

    Science.gov (United States)

    Aminiaghdam, Soran; Rode, Christian; Müller, Roy; Blickhan, Reinhard

    2017-02-01

    Pronograde trunk orientation in small birds causes prominent intra-limb asymmetries in the leg function. As yet, it is not clear whether these asymmetries induced by the trunk reflect general constraints on the leg function regardless of the specific leg architecture or size of the species. To address this, we instructed 12 human volunteers to walk at a self-selected velocity with four postures: regular erect, or with 30 deg, 50 deg and maximal trunk flexion. In addition, we simulated the axial leg force (along the line connecting hip and centre of pressure) using two simple models: spring and damper in series, and parallel spring and damper. As trunk flexion increases, lower limb joints become more flexed during stance. Similar to birds, the associated posterior shift of the hip relative to the centre of mass leads to a shorter leg at toe-off than at touchdown, and to a flatter angle of attack and a steeper leg angle at toe-off. Furthermore, walking with maximal trunk flexion induces right-skewed vertical and horizontal ground reaction force profiles comparable to those in birds. Interestingly, the spring and damper in series model provides a superior prediction of the axial leg force across trunk-flexed gaits compared with the parallel spring and damper model; in regular erect gait, the damper does not substantially improve the reproduction of the human axial leg force. In conclusion, mimicking the pronograde locomotion of birds by bending the trunk forward in humans causes a leg function similar to that of birds despite the different morphology of the segmented legs. © 2017. Published by The Company of Biologists Ltd.

  19. Collisional relaxation of electron tail distribution

    International Nuclear Information System (INIS)

    Yamagiwa, Mitsuru; Okamoto, Masao.

    1985-05-01

    Relaxation due to the Coulomb collisions of the electron velocity distribution function with a high energy tail is investigated in detail. In the course of the relaxation, a 'saddle' point can be created in velocity space owing to upsilon -3 dependence of the deflection rate and a positive slope or a 'dip' appears in the tail direction. The time evolution of the electron tail is studied analytically. A comparison is made with numerical results by using a Fokker-Planck code. Also discussed is the kinetic instability concerned with the positive slope during the relaxation. (author)

  20. Human genes for complement components C1r and C1s in a close tail-to-tail arrangement

    International Nuclear Information System (INIS)

    Kusumoto, H.; Hirosawa, S.; Salier, J.P.; Hagen, F.S.; Kurachi, K.

    1988-01-01

    Complementary DNA clones for human C1s were isolated from cDNA libraries that were prepared with poly(A) + RNAs of human liver and HepG2 cells. A clone with the largest cDNA insert of 2,664 base pairs (bp) was analyzed for its complete nucleotide sequence. It contained 202 bp of a 5' untranslated region, 45 bp of coding for a signal peptide (15 amino acid residues), 2,019 bp for complement component C1s zymogen (673 amino acid residues), 378 bp for a 3' untranslated region, a stop codon, and 17 bp of a poly(A) tail. The amino acid sequence of C1s was 40.5% identical to that of C1r, with excellent matches of tentative disulfide bond locations conserving the overall domain structure of C1r. DNA blotting and sequencing analyses of genomic DNA and of an isolated genomic DNA clone clearly showed that the human genes for C1r and C1s are closely located in a tail-to-tail arrangement at a distance of about 9.5 kilobases. Furthermore, RNA blot analyses showed that both C1r and C1s genes are primarily expressed in liver, whereas most other tissues expressed both C1r and C1s genes at much lower levels (less than 10% of that in liver). Multiple molecular sizes of specific mRNAs were observed in the RNA blot analyses for both C1r and C1s, indicating that alternative RNA processing(s), likely an alternative polyadenylylation, might take place for both genes

  1. Calcium-sensitivity of smooth muscle contraction in the isolated ...

    African Journals Online (AJOL)

    sensitivity of smooth muscle contraction were studied in the isolated perfused rat tail artery, employing the activators noradrenaline (NA) (3ìM) sand potassium chloride (KC1) (100mM). Experiments were conduced in Ca2+ - buffered saline.

  2. Variability of ischiofemoral space dimensions with changes in hip flexion: an MRI study

    International Nuclear Information System (INIS)

    Johnson, Adam C.; Howe, Benjamin M.; Hollman, John H.; Finnoff, Jonathan T.

    2017-01-01

    The primary aim of this study was to determine if ischiofemoral space (IFS) dimensions vary with changes in hip flexion as a result of placing a bolster behind the knees during magnetic resonance imaging (MRI). A secondary aim was to determine if IFS dimensions vary between supine and prone hip neutral positions. The study employed a prospective design. Sports medicine center within a tertiary care institution. Five male and five female adult subjects (age mean = 29.2, range = 23-35; body mass index [BMI] mean = 23.5, range = 19.5-26.6) were recruited to participate in the study. An axial, T1-weighted MRI sequence of the pelvis was obtained of each subject in a supine position with their hips in neutral and flexed positions, and in a prone position with their hips in neutral position. Supine hip flexion was induced by placing a standard, 9-cm-diameter MRI knee bolster under the subject's knees. The order of image acquisition (supine hip neutral, supine hip flexed, prone hip neutral) was randomized. The IFS dimensions were then measured on a separate workstation. The investigator performing the IFS measurements was blinded to the subject position for each image. The main outcome measurements were the IFS dimensions acquired with MRI. The mean IFS dimensions in the prone position were 28.25 mm (SD 5.91 mm, standard error mean 1.32 mm). In the supine hip neutral position, the IFS dimensions were 25.1 (SD 5.6) mm. The mean difference between the two positions of 3.15 (3.6) mm was statistically significant (95 % CI of the difference = 1.4 to 4.8 mm, t_1_9 = 3.911, p =.001). The mean IFS dimensions in the hip flexed position were 36.9 (SD 5.7) mm. The mean difference between the two supine positions of 11.8 (4.1) mm was statistically significant (95 % CI of the difference = 9.9 to 13.7 mm, t_1_9 = 12.716, p <.001). Our findings demonstrate that the IFS measurements obtained with MRI are dependent upon patient positioning with respect to hip flexion and supine versus

  3. Variability of ischiofemoral space dimensions with changes in hip flexion: an MRI study

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Adam C.; Howe, Benjamin M. [Mayo Clinic College of Medicine, Department of Radiology, Rochester, MN (United States); Hollman, John H.; Finnoff, Jonathan T. [Mayo Clinic College of Medicine, Department of Physical Medicine and Rehabilitation, Rochester, MN (United States)

    2017-01-15

    The primary aim of this study was to determine if ischiofemoral space (IFS) dimensions vary with changes in hip flexion as a result of placing a bolster behind the knees during magnetic resonance imaging (MRI). A secondary aim was to determine if IFS dimensions vary between supine and prone hip neutral positions. The study employed a prospective design. Sports medicine center within a tertiary care institution. Five male and five female adult subjects (age mean = 29.2, range = 23-35; body mass index [BMI] mean = 23.5, range = 19.5-26.6) were recruited to participate in the study. An axial, T1-weighted MRI sequence of the pelvis was obtained of each subject in a supine position with their hips in neutral and flexed positions, and in a prone position with their hips in neutral position. Supine hip flexion was induced by placing a standard, 9-cm-diameter MRI knee bolster under the subject's knees. The order of image acquisition (supine hip neutral, supine hip flexed, prone hip neutral) was randomized. The IFS dimensions were then measured on a separate workstation. The investigator performing the IFS measurements was blinded to the subject position for each image. The main outcome measurements were the IFS dimensions acquired with MRI. The mean IFS dimensions in the prone position were 28.25 mm (SD 5.91 mm, standard error mean 1.32 mm). In the supine hip neutral position, the IFS dimensions were 25.1 (SD 5.6) mm. The mean difference between the two positions of 3.15 (3.6) mm was statistically significant (95 % CI of the difference = 1.4 to 4.8 mm, t{sub 19} = 3.911, p =.001). The mean IFS dimensions in the hip flexed position were 36.9 (SD 5.7) mm. The mean difference between the two supine positions of 11.8 (4.1) mm was statistically significant (95 % CI of the difference = 9.9 to 13.7 mm, t{sub 19} = 12.716, p <.001). Our findings demonstrate that the IFS measurements obtained with MRI are dependent upon patient positioning with respect to hip flexion and

  4. Age-related decreases in motor unit discharge rate and force control during isometric plantar flexion

    DEFF Research Database (Denmark)

    Kallio, J; Søgaard, Karen; Avela, J

    2012-01-01

    Aging is related to multiple changes in muscle physiology and function. Previous findings concerning the effects of aging on motor unit discharge rate (DR) and fluctuations in DR and force are somewhat contradictory. Eight YOUNG and nine OLD physically active males performed isometric ramp (RECR......) and isotonic (ISO) plantar flexions at 10 and 20% of surface EMG at MVC. Motor unit (MU) action potentials were recorded with intramuscular fine-wire electrodes and decomposed with custom build software "Daisy". DR was lower in OLD in RECR-10% (17.9%, p...

  5. Knee joint moments during high flexion movements: Timing of peak moments and the effect of safety footwear.

    Science.gov (United States)

    Chong, Helen C; Tennant, Liana M; Kingston, David C; Acker, Stacey M

    2017-03-01

    (1) Characterize knee joint moments and peak knee flexion moment timing during kneeling transitions, with the intent of identifying high-risk postures. (2) Determine whether safety footwear worn by kneeling workers (construction workers, tile setters, masons, roofers) alters high flexion kneeling mechanics. Fifteen males performed high flexion kneeling transitions. Kinetics and kinematics were analyzed for differences in ascent and descent in the lead and trail legs. Mean±standard deviation peak external knee adduction and flexion moments during transitions ranged from 1.01±0.31 to 2.04±0.66% body weight times height (BW∗Ht) and from 3.33 to 12.6% BW∗Ht respectively. The lead leg experienced significantly higher adduction moments compared to the trail leg during descent, when work boots were worn (interaction, p=0.005). There was a main effect of leg (higher lead vs. trail) on the internal rotation moment in both descent (p=0.0119) and ascent (p=0.0129) phases. Peak external knee adduction moments during transitions did not exceed those exhibited during level walking, thus increased knee adduction moment magnitude is likely not a main factor in the development of knee OA in occupational kneelers. Additionally, work boots only significantly increased the adduction moment in the lead leg during descent. In cases where one knee is painful, diseased, or injured, the unaffected knee should be used as the lead leg during asymmetric bilateral kneeling. Peak flexion moments occurred at flexion angles above the maximum flexion angle exhibited during walking (approximately 60°), supporting the theory that the loading of atypical surfaces may aid disease development or progression. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Cameco engineered tailings program: linking applied research with industrial processes for improved tailings performance

    International Nuclear Information System (INIS)

    Kotzer, T.G.

    2010-01-01

    'Full text:' Mine tailings at Cameco's operations are by-products of milling uranium ore having variable concentrations of uranium, metals, oxyanions and trace elements or elements of concern (EOC). Cameco has undertaken an Engineered Tailings (ET) program to optimize tailings performance and minimize environmental EOC impacts, regardless of the milled ore source. Applied geochemical and geotechnical tailings research is key within the ET program. In-situ drilling and experimental programs are used to understand long-term tailings behaviour and help validate source term predictions. Within this, the ET program proactively aids in the development of mill-based processes for production of tailings having improved long-term stability. (author)

  7. Characterization and monitoring of transverse beam tails

    International Nuclear Information System (INIS)

    Seeman, J.T.; Decker, F.J.; Hsu, I.; Young, C.

    1991-05-01

    Low emittance electron beams accelerated to high energy in a linac experience transverse effects (wakefield, filamentation, optics) which produce non-Gaussian projected transverse beam distributions. Characterizations of the beam shapes are difficult because the shapes are asymmetric and change with betatron phase. In this note several methods to describe beam distributions are discussed including an accelerator physics model of these tails. The uses of these characterizations in monitoring the beam emittances in the SLC are described in this paper. First, two dimensional distributions from profile monitor screens are reviewed showing correlated tails. Second, a fitting technique for non-Gaussian one dimensional distributions is used to extract the core from the tail areas. Finally, a model for tail propagation in the linac is given. 3 refs., 6 figs

  8. Some properties of Suncor oil sands tailings

    Energy Technology Data Exchange (ETDEWEB)

    Guo, C.; Wells, P.S. [Suncor Energy, Fort McMurray, AB (Canada)

    2010-07-01

    This PowerPoint presentation discussed a pond assessment program conducted by Suncor to determine the properties of mature fine tailings (MFT) and composite tailings (CT) at reclaimed and unreclaimed sites. Mudline and sonar depth sounding techniques were used to determine solids contents. A wire line sampler provided point depth samples used for laboratory analyses. Continuous drill samples were obtained in order to characterize bottom fines and clay content. A flow penetration tests was used to determine the undrained shear strength of the soft tailings. A 3-D block model was then used to estimate soft material properties and to generate material distribution volumes and tonnages for different property ranges. The study showed that the block modelling techniques provide a more accurate tailings pond assessment than traditional approaches. While slow, ongoing static consolidation was observed, surface capping and artificial dewatering are required to provide trafficable ground for the final reclamation of the sites. tabs., figs.

  9. Unique structural features facilitate lizard tail autotomy.

    Directory of Open Access Journals (Sweden)

    Kristian W Sanggaard

    Full Text Available Autotomy refers to the voluntary shedding of a body part; a renowned example is tail loss among lizards as a response to attempted predation. Although many aspects of lizard tail autotomy have been studied, the detailed morphology and mechanism remains unclear. In the present study, we showed that tail shedding by the Tokay gecko (Gekko gecko and the associated extracellular matrix (ECM rupture were independent of proteolysis. Instead, lizard caudal autotomy relied on biological adhesion facilitated by surface microstructures. Results based on bio-imaging techniques demonstrated that the tail of Gekko gecko was pre-severed at distinct sites and that its structural integrity depended on the adhesion between these segments.

  10. BIOMECHANICS. Why the seahorse tail is square.

    Science.gov (United States)

    Porter, Michael M; Adriaens, Dominique; Hatton, Ross L; Meyers, Marc A; McKittrick, Joanna

    2015-07-03

    Whereas the predominant shapes of most animal tails are cylindrical, seahorse tails are square prisms. Seahorses use their tails as flexible grasping appendages, in spite of a rigid bony armor that fully encases their bodies. We explore the mechanics of two three-dimensional-printed models that mimic either the natural (square prism) or hypothetical (cylindrical) architecture of a seahorse tail to uncover whether or not the square geometry provides any functional advantages. Our results show that the square prism is more resilient when crushed and provides a mechanism for preserving articulatory organization upon extensive bending and twisting, as compared with its cylindrical counterpart. Thus, the square architecture is better than the circular one in the context of two integrated functions: grasping ability and crushing resistance. Copyright © 2015, American Association for the Advancement of Science.

  11. Elemental characterization of Tummalapalle uranium mill tailing

    International Nuclear Information System (INIS)

    Patra, A.C.; Sahoo, S.K.; Thakur, V.K.; Dubey, J.S.; Jha, S.K.; Tripathi, R.M.; Sharma, D.B.

    2018-01-01

    Elements are present in environmental matrices at varying concentrations. Their levels may increase due to anthropogenic activities like transportation, industrial activities, agriculture, urbanization and human activities. Trace elements can be classified as potentially toxic (eg. cadmium, arsenic, mercury, lead, nickel), probably essential (eg. cobalt, vanadium) and essential (eg. iron, zinc, copper, selenium, manganese). Due to the expansion of the Indian Nuclear Power Programme, new uranium mining sites are coming up. Mining and milling produce large quantities of low active mill tailings contained in engineered Tailings Ponds. The tailings are amenable for interaction with the geochemical forces and can act as potential sources of contamination. Thus it is necessary to ascertain the concentrations of elements that are present therein. In this paper we aim to characterize the uranium tailings generated from Tummalapalle uranium mining facility in Kadappa district, Andhra Pradesh, India

  12. On Estimation and Testing for Pareto Tails

    Czech Academy of Sciences Publication Activity Database

    Jordanova, P.; Stehlík, M.; Fabián, Zdeněk; Střelec, L.

    2013-01-01

    Roč. 22, č. 1 (2013), s. 89-108 ISSN 0204-9805 Institutional support: RVO:67985807 Keywords : testing against heavy tails * asymptotic properties of estimators * point estimation Subject RIV: BB - Applied Statistics, Operational Research

  13. Electrodialytic remediation of suspended mine tailings

    DEFF Research Database (Denmark)

    Hansen, Henrik K.; Rojo, Adrian; Pino, Denisse

    2008-01-01

    This work shows the laboratory results of nine electrodialytic remediation experiments on copper mine tailings. A newly designed remediation cell, where the solids were kept in suspension by airflow, was tested. The results show that electric current could remove copper from suspended tailings...... efficiency from 1% to 80% compared to experiments with no stirring but with the same operational conditions. This showed the crucial importance of having the solids in suspension and not settled during the remediation....

  14. Electrodialytic Remediation of Copper Mine Tailings

    DEFF Research Database (Denmark)

    Hansen, H.K.; Rojo, A.; Ottosen, L.M.

    2012-01-01

    This work compares and evaluates sixteen electrodialytic laboratory remediation experiments on copper mine tailings. Different parameters were analysed, such as remediation time, addition of desorbing agents, and the use of pulsed electrical fields.......This work compares and evaluates sixteen electrodialytic laboratory remediation experiments on copper mine tailings. Different parameters were analysed, such as remediation time, addition of desorbing agents, and the use of pulsed electrical fields....

  15. TIDAL TAILS OF MINOR MERGERS. II. COMPARING STAR FORMATION IN THE TIDAL TAILS OF NGC 2782

    Energy Technology Data Exchange (ETDEWEB)

    Knierman, Karen A.; Scowen, Paul; Veach, Todd; Groppi, Christopher [School of Earth and Space Exploration, Arizona State University, 550 E. Tyler Mall, Room PSF-686 (P.O. Box 871404), Tempe, AZ 85287-1404 (United States); Mullan, Brendan; Charlton, Jane [Department of Astronomy and Astrophysics, Penn State University, 525 Davey Lab, University Park, PA (United States); Konstantopoulos, Iraklis [Australian Astronomical Observatory, P.O. Box 915, North Ryde NSW 1670 (Australia); Knezek, Patricia M., E-mail: karen.knierman@asu.edu, E-mail: paul.scowen@asu.edu, E-mail: tveach@asu.edu, E-mail: cgroppi@asu.edu, E-mail: mullan@astro.psu.edu, E-mail: iraklis@aao.gov.au, E-mail: pknezek@noao.edu [WIYN Consortium, Inc., 950 N. Cherry Avenue, Tucson, AZ 85719 (United States)

    2013-09-10

    The peculiar spiral NGC 2782 is the result of a minor merger with a mass ratio {approx}4: 1 occurring {approx}200 Myr ago. This merger produced a molecular and H I-rich, optically bright eastern tail and an H I-rich, optically faint western tail. Non-detection of CO in the western tail by Braine et al. suggested that star formation had not yet begun. However, deep UBVR and H{alpha} narrowband images show evidence of recent star formation in the western tail, though it lacks massive star clusters and cluster complexes. Using Herschel PACS spectroscopy, we discover 158 {mu}m [C II] emission at the location of the three most luminous H{alpha} sources in the eastern tail, but not at the location of the even brighter H{alpha} source in the western tail. The western tail is found to have a normal star formation efficiency (SFE), but the eastern tail has a low SFE. The lack of CO and [C II] emission suggests that the western tail H II region may have a low carbon abundance and be undergoing its first star formation. The western tail is more efficient at forming stars, but lacks massive clusters. We propose that the low SFE in the eastern tail may be due to its formation as a splash region where gas heating is important even though it has sufficient molecular and neutral gas to make massive star clusters. The western tail, which has lower gas surface density and does not form high-mass star clusters, is a tidally formed region where gravitational compression likely enhances star formation.

  16. TIDAL TAILS OF MINOR MERGERS. II. COMPARING STAR FORMATION IN THE TIDAL TAILS OF NGC 2782

    International Nuclear Information System (INIS)

    Knierman, Karen A.; Scowen, Paul; Veach, Todd; Groppi, Christopher; Mullan, Brendan; Charlton, Jane; Konstantopoulos, Iraklis; Knezek, Patricia M.

    2013-01-01

    The peculiar spiral NGC 2782 is the result of a minor merger with a mass ratio ∼4: 1 occurring ∼200 Myr ago. This merger produced a molecular and H I-rich, optically bright eastern tail and an H I-rich, optically faint western tail. Non-detection of CO in the western tail by Braine et al. suggested that star formation had not yet begun. However, deep UBVR and Hα narrowband images show evidence of recent star formation in the western tail, though it lacks massive star clusters and cluster complexes. Using Herschel PACS spectroscopy, we discover 158 μm [C II] emission at the location of the three most luminous Hα sources in the eastern tail, but not at the location of the even brighter Hα source in the western tail. The western tail is found to have a normal star formation efficiency (SFE), but the eastern tail has a low SFE. The lack of CO and [C II] emission suggests that the western tail H II region may have a low carbon abundance and be undergoing its first star formation. The western tail is more efficient at forming stars, but lacks massive clusters. We propose that the low SFE in the eastern tail may be due to its formation as a splash region where gas heating is important even though it has sufficient molecular and neutral gas to make massive star clusters. The western tail, which has lower gas surface density and does not form high-mass star clusters, is a tidally formed region where gravitational compression likely enhances star formation

  17. Effect of Ankle Positioning During Hamstring Stretches for Improving Straight Leg Hip Flexion Motion.

    Science.gov (United States)

    Laudner, Kevin G; Benjamin, Peter J; Selkow, Noelle M

    2016-03-01

    To compare the effects of stretching the hamstrings with the ankle in either a plantar-flexed (PF) or dorsiflexed (DF) position for improving straight leg hip flexion range of motion (ROM) over a 4-week period. Randomized, single-blinded, pretest, posttest design. Athletic training facility. Each limb of 34 asymptomatic individuals (15 males, 19 females) was randomly assigned to one of the 3 groups. Twenty-four limbs received hamstring stretches with the ankle in DF, 24 limbs received hamstring stretches with the ankle in PF, and 20 limbs received no stretch (control). Ankle position (PF, DF) during hamstring stretching. We measured pretest and posttest passive straight leg hip flexion ROM with the test ankle in a neutral position. For the intervention groups, the test limb was passively stretched with the ankle held in end range DF or PF for their respective group. Each stretch was held for 30 seconds for a total of 3 applications. Two treatment sessions were completed per week for a total of 4 weeks. The control limbs received no stretching during the 4-week period. We conducted 1-way analyses of covariance to determine significant changes in ROM between groups (P hamstrings in either PF or DF improve straight leg hip ROM compared with a control group. The results of this study should be considered by clinicians when determining the optimal stretching techniques aimed at increasing hamstring length.

  18. Rites thérapeutiques : réflexion sur le terrain et les archives

    Directory of Open Access Journals (Sweden)

    Chantal Radimilahy

    2008-08-01

    Full Text Available Rites thérapeutiques : réflexion sur le terrain et les archives. En comparant la façon dont l’écrit sert à noter et à fixer des pratiques de guérissage, d’une part dans les archives de L. Vig et d’autre part dans les carnets d’un guérisseur malgache contemporain, l’auteur esquisse une réflexion sur la stabilité apparente des formes du langage et des pratiques rituelles dans un contexte social transformé.Therapeutic rituals: consideration on fieldwork and archives. By comparing the way in which writing is used to record and establish traditional healing practices, on the one hand in the archives of L. Vig and on the other, in the notes of a contemporary Madagascan traditional healer, the author outlines her reflections on the apparent stability of language forms and ritual practices in a transformed social context.

  19. Knee flexion contracture treated with botulinum toxin type A in patients with haemophilia (PWH).

    Science.gov (United States)

    Daffunchio, C; Caviglia, H; Nassif, J; Morettil, N; Galatro, G

    2016-01-01

    Knee flexion contracture (KFC) remains a common complication of haemoarthrosis in children and young adults with haemophilia. If the KFC is not treated properly it produces disability, postural and gait abnormalities. Evaluate the effectiveness of conservative treatment of KFC with Botulinum toxin type A (BTX-A) in PWH. Seventeen patients were treated, with 21 affected knees. Mean age was 26 years. The mean follow up was 12 months. We evaluated flexion and KFC pretreatment BTX-A and up to 12 months posttreatment. BTX-A application was in hamstring and calf muscles. To evaluate the function, a questionnaire about different activities was made, and it was checked 3, 6 and 12 months after BTX-A. According to the degree of KFC, knees were divided into 3 groups: Group 1: -10° to -30° (n = 10), Group 2: -31° to -45° (n = 6) Group 3: -46° or more (n = 5). The average KFC improved from -38° to -24°. The improvement was 14° (P KFC improvement was 9° in group 1, 17° in group 2, and 23° in group 3. There was a high correlation between the improvement in KFC and the total score of the questionnaire R = 0.77. Treatment of KFC with BTX-A improves knee-related functional activities, with the advantage of being a low-cost procedure and easy to apply. © 2015 John Wiley & Sons Ltd.

  20. Comportement en flexion des bétons fibrés sous chargement cyclique

    Directory of Open Access Journals (Sweden)

    Boulekbache Bensaid

    2014-04-01

    Full Text Available Ce papier présente les résultats d’une étude expérimentale sur le comportement en flexion des bétons de fibres métalliques. On étudie l’effet de la rhéologie du béton sur l’orientation des fibres et l’influence de l’orientation sur les propriétés mécaniques. La rigidité de l’ancrage des fibres étudiée par les essais cycliques est liée aux caractéristiques rhéologiques et mécaniques de la matrice. Les résultats montrent que la fluidité des bétons est un paramètre essentiel de l’orientation des fibres. Dès lors que l’on obtient une orientation dans le sens de l’efficacité mécanique, la résistance à la flexion est nettement améliorée.

  1. Canadian experience with uranium tailings disposal

    International Nuclear Information System (INIS)

    Culver, K.B.

    1982-06-01

    During the first years of uranium production in Canada uranium tailings were discharged directly into valleys or lakes near the mill. Treatment with barium chloride to precipitate radium began in 1965 at the Nordic Mine at Elliot Lake, Ontario. In the mid-60s and early 70s water quality studies indicated that discharges from uranium tailings areas were causing degradation to the upper part of the Serpent River water system. Studies into acid generation, revegetation, and leaching of radium were initiated by the mining companies and resulted in the construction of treatment plants at a number of sites. Abandoned tailings sites were revegetated. At hearings into the expansion of the Elliot Lake operations the issue of tailings management was a major item for discussion. As a result federal and provincial agencies developed guidelines for the siting and development of urnaium tailings areas prior to issuing operating licences. Western Canadian uranium producers do not have the acid generation problem of the Elliot Lake operations. The Rabbit Lake mill uses settling ponds followed by filtration. High-grade tailings from Cluff Lake are sealed in concrete and buried. Uranium producers feel that the interim criteria developed by the Atomic Energy Control Board, if adopted, would have a harmful effect on the viability of the Canadian uranium industry

  2. Four tails problems for dynamical collapse theories

    Science.gov (United States)

    McQueen, Kelvin J.

    2015-02-01

    The primary quantum mechanical equation of motion entails that measurements typically do not have determinate outcomes, but result in superpositions of all possible outcomes. Dynamical collapse theories (e.g. GRW) supplement this equation with a stochastic Gaussian collapse function, intended to collapse the superposition of outcomes into one outcome. But the Gaussian collapses are imperfect in a way that leaves the superpositions intact. This is the tails problem. There are several ways of making this problem more precise. But many authors dismiss the problem without considering the more severe formulations. Here I distinguish four distinct tails problems. The first (bare tails problem) and second (structured tails problem) exist in the literature. I argue that while the first is a pseudo-problem, the second has not been adequately addressed. The third (multiverse tails problem) reformulates the second to account for recently discovered dynamical consequences of collapse. Finally the fourth (tails problem dilemma) shows that solving the third by replacing the Gaussian with a non-Gaussian collapse function introduces new conflict with relativity theory.

  3. Consistency based correlations for tailings consolidation

    Energy Technology Data Exchange (ETDEWEB)

    Azam, S.; Paul, A.C. [Regina Univ., Regina, SK (Canada). Environmental Systems Engineering

    2010-07-01

    The extraction of oil, uranium, metals and mineral resources from the earth generates significant amounts of tailings slurry. The tailings are contained in a disposal area with perimeter dykes constructed from the coarser fraction of the slurry. There are many unique challenges pertaining to the management of the containment facilities for several decades beyond mine closure that are a result of the slow settling rates of the fines and the high standing toxic waters. Many tailings dam failures in different parts of the world have been reported to result in significant contaminant releases causing public concern over the conventional practice of tailings disposal. Therefore, in order to reduce and minimize the environmental footprint, the fluid tailings need to undergo efficient consolidation. This paper presented an investigation into the consolidation behaviour of tailings in conjunction with soil consistency that captured physicochemical interactions. The paper discussed the large strain consolidation behaviour (volume compressibility and hydraulic conductivity) of six fine-grained soil slurries based on published data. The paper provided background information on the study and presented the research methodology. The geotechnical index properties of the selected materials were also presented. The large strain consolidation, volume compressibility correlations, and hydraulic conductivity correlations were provided. It was concluded that the normalized void ratio best described volume compressibility whereas liquidity index best explained the hydraulic conductivity. 17 refs., 3 tabs., 4 figs.

  4. The Sodium Tail of the Moon

    Science.gov (United States)

    Matta, M.; Smith, S.; Baumgardner, J.; Wilson, J.; Martinis, C.; Mendillo, M.

    2009-01-01

    During the few days centered about new Moon, the lunar surface is optically hidden from Earth-based observers. However, the Moon still offers an observable: an extended sodium tail. The lunar sodium tail is the escaping "hot" component of a coma-like exosphere of sodium generated by photon-stimulated desorption, solar wind sputtering and meteoroid impact. Neutral sodium atoms escaping lunar gravity experience solar radiation pressure that drives them into the anti-solar direction forming a comet-like tail. During new Moon time, the geometry of the Sun, Moon and Earth is such that the anti-sunward sodium flux is perturbed by the terrestrial gravitational field resulting in its focusing into a dense core that extends beyond the Earth. An all-sky camera situated at the El Leoncito Observatory (CASLEO) in Argentina has been successfully imaging this tail through a sodium filter at each lunation since April 2006. This paper reports on the results of the brightness of the lunar sodium tail spanning 31 lunations between April 2006 and September 2008. Brightness variability trends are compared with both sporadic and shower meteor activity, solar wind proton energy flux and solar near ultra violet (NUV) patterns for possible correlations. Results suggest minimal variability in the brightness of the observed lunar sodium tail, generally uncorrelated with any single source, yet consistent with a multi-year period of minimal solar activity and non-intense meteoric fluxes.

  5. Attitudes of Dutch Pig Farmers Towards Tail Biting and Tail Docking

    OpenAIRE

    Bracke, M.B.M.; Lauwere, de, C.C.; Wind, S.M.M.; Zonderland, J.J.

    2013-01-01

    The Dutch policy objective of a fully sustainable livestock sector without mutilations by 2023 is not compatible with the routine practice of tail docking to minimize the risk of tail biting. To examine farmer attitudes towards docking, a telephone survey was conducted among 487 conventional and 33 organic Dutch pig farmers. “Biting” (of tails, ears, or limbs) was identified by the farmers as a main welfare problem in pig farming. About half of the farmers reported to have no tail biting prob...

  6. Quantifying the lumbar flexion-relaxation phenomenon: theory, normative data, and clinical applications.

    Science.gov (United States)

    Neblett, Randy; Mayer, Tom G; Gatchel, Robert J; Keeley, Janice; Proctor, Tim; Anagnostis, Christopher

    2003-07-01

    A two-part investigation was conducted: 1) a prospective study of asymptomatic subjects quantitatively comparing trunk mobility to surface electromyographic (sEMG) signals from the erector spinae during trunk flexion; and 2) a prospective repeated-measures cohort study of patients with chronic disabled work-related spinal disorder tested for the flexion-relaxation (FR) phenomenon while measured simultaneously for lumbar spine inclinometric range of motion (ROM). To describe a theoretical model for the potential use of FR unloaded in assessing patients with chronic low back pain patients before and after rehabilitation, and to establish a normative database (Part 1) for subsequent use in comparison to patients with chronic low back pain (Part 2). The second part of the study assessed the clinical utility of combined sEMG and ROM measurements for assessing the FR phenomenon as a test to assist potentially in planning rehabilitation programs, guiding patients' individual rehabilitation progress, and identifying early posttreatment outcome failures. The FR phenomenon has been recognized since 1951, and it can be reproducibly assessed in normal subjects with FR unloaded. It can be found intermittently in patients with chronic low back pain. Recent studies have moved toward deriving formulas to identify FR, but only a few have examined a potential relation between inclinometric lumbar motion measures and the sEMG signal. No previous studies have developed normative data potentially useful for objectively assessing nonoperative treatment progress, effort, or the validity of permanent impairment rating measures. In Part 1, 12 asymptomatic subjects were evaluated in an intra- and interrater repeated-measures protocol to examine reliability of sEMG signal readings in FR, as well as ROM measures at FR and maximum voluntary flexion. The mean sEMG signal averaging right-left electrode recordings, as well as the gross, true, and sacral lumbar ROM measurements, were recorded as

  7. Sonographic measurements of the ulnar nerve at the elbow with different degrees of elbow flexion.

    Science.gov (United States)

    Patel, Prutha; Norbury, John W; Fang, Xiangming

    2014-05-01

    To determine whether there were differences in the cross-sectional area (CSA) and the flattening ratio of the normative ulnar nerve as it passes between the medial epicondyle and the olecranon at 30° of elbow flexion versus 90° of elbow flexion. Bilateral upper extremities of normal healthy adult volunteers were evaluated with ultrasound. The CSA and the flattening ratio of the ulnar nerve at the elbow as it passes between the medial epicondyle and the olecranon were measured, with the elbow flexed at 30° and at 90°, by 2 operators with varying ultrasound scanning experience by using ellipse and direct tracing methods. The results from the 2 different angles of elbow flexion were compared for each individual operator. Finally, intraclass correlations for absolute agreement and consistency between the 2 raters were calculated. An outpatient clinic room at a regional rehabilitation center. Twenty-five normal healthy adult volunteers. The mean CSA and the mean flattening ratio of the ulnar nerve at 30° of elbow flexion and at 90° of elbow flexion. First, for the ellipse method, the mean CSA of the ulnar nerve at 90° (9.93 mm(2)) was slightly larger than at 30° (9.77 mm(2)) for rater 1. However, for rater 2, the mean CSA of the ulnar nerve at 90° (6.80 mm(2)) was slightly smaller than at 30° (7.08 mm(2)). This was found to be statistically insignificant when using a matched pairs t test and the Wilcoxon signed-rank test, with a significance level of .05. Similarly, the difference between the right side and the left side was not statistically significant. The intraclass correlations for absolute agreement between the 2 raters were not very high due to different measurement locations, but the intraclass correlations for consistency were high. Second, for the direct tracing method, the mean CSA at 90° (7.26 mm(2)) was slightly lower than at 30° (7.48 mm(2)). This was found to be statistically nonsignificant when using the matched pairs t test and the

  8. Déficit bilateral nos movimentos de flexão e extensão de perna e flexão do cotovelo Déficit bilateral en los movimientos de flexion y extension de la pierna y flexion del codo Bilateral deficit in leg flexion and extension and elbow flexion movements

    Directory of Open Access Journals (Sweden)

    Christianne Pereira Giesbrecht Chaves

    2004-12-01

    áxima (CM en la flexión y extensión de pierna e flexión del de codo aisladamente y entre la suma de esos dos resultados con aquel desarrollado simultaneamente por las dos piernas y los dos brazos, respectivamente. Sometemos a 60 indivíduos al ejercicio de flexión y extensión de pierna y a flexión de codo a un test de 1RM. Los resultados para los movimientos de flexión y extensión de pierna y flexión de codo izquierdos y derechos en la CM fueron de 31,6 (± 7,9, 32,0 (± 8,0, 20,2 (± 9,2, 20,2 (± 9,8, 29,3 (± 13,9 e 29,8 (± 14,1 kg respectivamente, y se mostraron similares (p > 0,05 y fuertemente asociados (r = 0,96, 0,96 e 0,98. Comparando la suma de los valores unilaterales con los de ejecución bilateral, la CM presentó una diferencia significativa para los movimientos de extensión de pierna (p = 0,04 y flexión de codo (p = 0,03, el mismo no fué observado en el movimiento de flexión de pierna (p = 0,75. Este resultado puede ser explicado por el menor incremento de carga - dos kilos y medio en este último movimiento en relación a los dos movimientos anteriores - cinco kilos. A pesar de la mayoría de los sujetos sean diestros, no hubo diferencias unilaterales en la CM a pesar de no todos estar entrenados. La suma de los resultados unilaterales fué mayor en 9,8% y 4,0% para los movimientos de extensión de la pierna y flexión del codo, respectivamente, de aquel obtenido bilateralmente, mostrando, probablemente una limitación central en la coordenación motora de un movimiento complejo hecho en máxima velocidad y con carga elevada. Por otro lado, en el movimiento de flexión de pierna, la suma de los resultados unilaterales fué inferior a la bilateral (-0,6%, presentando un posible aprendizage del movimiento y adaptación al entrenamiento con pesos a partir de las doce semanas.Endurance exercises (EE may be performed unilaterally and bilaterally. The objective was to compare the maximum load (ML in leg flexion and extension and elbow flexion alone

  9. Biceps Tendon Lengthening Surgery for Failed Serial Casting Patients With Elbow Flexion Contractures Following Brachial Plexus Birth Injury.

    Science.gov (United States)

    Nath, Rahul K; Somasundaram, Chandra

    2016-01-01

    Assessment of surgical outcomes of biceps tendon lengthening (BTL) surgery in obstetric brachial plexus injury (OBPI) patients with elbow flexion contractures, who had unsuccessful serial casting. Serial casting and splinting have been shown to be effective in correcting elbow flexion contractures in OBPI. However, the possibilities of radial head dislocations and other complications have been reported in serial casting and splinting. Literature indicates surgical intervention when such nonoperative techniques and range-of-motion exercises fail. Here, we demonstrated a significant reduction of the contractures of the affected elbow and improvement in arm length to more normal after BTL in these patients, who had unsuccessful serial casting. Ten OBPI patients (6 girls and 4 boys) with an average age of 11.2 years (4-17.7 years) had BTL surgery after unsuccessful serial casting. Mean elbow flexion contracture was 40° before and 37° (average) after serial casting. Mean elbow flexion contracture was reduced to 8° (0°-20°) post-BTL surgical procedure with an average follow-up of 11 months. This was 75% improvement and statistically significant (P casting. These OBPI patients in our study had 75% significant reduction in elbow flexion contractures and achieved an improved and more normal length of the affected arm after the BTL surgery when compared to only 7% insignificant reduction and no improvement in arm length after serial casting.

  10. Dewatering Behaviour of Fine Oil Sands Tailings : An Experimental Study

    NARCIS (Netherlands)

    Yao, Y.

    2016-01-01

    Oil sands tailings are a warm aqueous suspension of sand, silt, clay, residual bitumen and naphtha. The tailings are hydraulically transported and stored in tailing ponds where they segregate, with the sand settling from suspension forming beaches and the remaining tailings flowing to the middle of

  11. Activity, tail loss, growth and survivorship of male Psammodromus algirus

    OpenAIRE

    Salvador Milla, Alfredo; Veiga, José Pablo

    2005-01-01

    Males with autotomized tail were sighted more often and moved longer distances than males with complete tail. There were no significant differences in survival between the two groups. The increase of snout-vent lenght at emergence the following year was significantly lower for males with autotomized tail than for males with complete tail.

  12. Limits theorems for tail processes with applications tointermediate quantile estimation

    NARCIS (Netherlands)

    Einmahl, J.H.J.

    1992-01-01

    A description of the weak and strong limiting behaviour of weighted uniform tail empirical and tail quantile processes is given. The results for the tail quantile process are applied to obtain weak and strong functional limit theorems for a weighted non-uniform tail-quantile-type process based on a

  13. Diagnostic analysis of electrodialysis in mine tailing materials

    DEFF Research Database (Denmark)

    Hansen, Henrik K.; Ribeiro, Alexandra B.; Mateus, Eduardo

    2007-01-01

    Removal of heavy metals from mine tailings and soil contaminated by copper mining activities was studied under batch electrodialytic conditions. Two types of mine tailings were treated: (i) freshly produced tailings coming directly from the flotation process, and (ii) tailings deposited...... in a tailings pond, for approximately 20 years. The main contaminant was copper-found in concentration around 800-1800 ppm. The fractionation of copper and other characteristics of the tailings differ for the two tailings, indicating natural oxidation reactions in the old deposited ones. Electrodialytical...

  14. Pengaruh Fungi Indigenous Toleran Zn terhadap Pertumbuhan Bibit Jagung di Media Tailing Steril

    Directory of Open Access Journals (Sweden)

    Ratna Santi

    2015-07-01

    Full Text Available Keberadaan logam Zn dalam jumlah tertentu di tailing pasca tambang akan berdampak pada rendahnya populasi mikroba tanah dan menghambat pertumbuhan tanaman. Aplikasi pemanfaatan fungi indigenus dari lahan tercemar merupakan salah satu usaha dalam memperbaiki sifat tanah untuk pertumbuhan tanaman. Penelitian ini bertujuan untuk mengetahui pengaruh inokulasi fungi dan toksisitas Zn terhadap pertumbuhan jagung pada fase VE-V9 di media tailing steril.  Fungi diisolasi dari tailing lahan pasca penambangan timah di Sungailiat  Bangka. Tiga isolat dari 15 isolat dipilih untuk pengujian pengaruh inokulasi fungi terhadap pertumbuhan jagung. Percobaan menggunakan Rancangan Acak Kelompok(RAK dua faktor dengan perlakuan jenis fungi dan konsentrasi Zn. Isolat yang digunakan toleran terhadap Zn pada konsentrasi 0-25 ppm dan mampu menghasilkan fitohormon. Hasil percobaan di rumah kaca menunjukkan bahwa inokulasi fungi nyata memperbaiki pertumbuhan jagung, dibandingkan tanpa inokulan. Serapan tertinggi ditunjukkan oleh isolat R 7J1, namun pertumbuhan jagung terbaik didapatkan dari inokulasi isolat B 2J1. The existence of Zn metal in a certain amount in the post tin mine tailings will result in low soil microbial populations and inhibit plant growth. Application of indigenous fungi utilization on contaminated land is one effort to improve soil properties for plant growth.This study aimed to determine the effect of inoculation of fungi and toxicity of zinc on the growth of corn in the phase of VE-V9 in sterile tailings medium. Fungi were isolated from post tin mining tailings tin lands in Bangka Sungailiat. Three isolates from 15 isolates were selected to test the effect of fungal inoculation on the growth of corn. Experiment used a Randomized Complete Block Design (RCBD two factors with fungi and Zn concentration treatments.Tolerant isolates used were at a concentration of 0-25 ppm Zn and capable to produce phytohormones. Result of experiment in greenhouse

  15. Atividade eletromiográfica no agachamento nas posições de 40º, 60º e 90º de flexão do joelho Electromyograhic activity in squatting at 40°, 60° and 90° knee flexion positions

    Directory of Open Access Journals (Sweden)

    Catarina de Oliveira Sousa

    2007-10-01

    biceps muscles with knee at 40° and 60° of flexion, with the trunk erect and in flexion and between the tibialis anterior and soleus muscles in the other positions (p < 0.05. Concerning isolated muscular activation, higher knee flexion in squatting was an important factor to greater muscles activation, except for the soleus. Trunk position and the additional load of 10 kg have influenced in the muscular activation of the femoris rectus at 60° of knee flexion, in which the erect trunk provided more activation. The femoris biceps presented greater activation when the knee was in 40° of flexion and the trunk flexioned. The co-activation between the femoris rectus and biceps with the trunk in flexion, and between the femoris rectus and soleus in the other positions, lead to new possibilities of exercises in rehabilitation.

  16. Electro-remediation of copper mine tailings. Comparing copper removal efficiencies for two tailings of different age

    DEFF Research Database (Denmark)

    Hansen, Henrik K.; Lamas, Victor; Gutierrez, Claudia

    2013-01-01

    This work compares and evaluates the copper removal efficiency when applying electric fields to two mine tailings originating from the same mine but of different age. Eight experiments were carried out - four on tailings deposited more than 20 years ago (old tailings) and four on tailings deposit...

  17. A new procedure for deep sea mining tailings disposal

    OpenAIRE

    Ma, W.; Schott, D.L.; Lodewijks, G.

    2017-01-01

    Deep sea mining tailings disposal is a new environmental challenge related to water pollution, mineral crust waste handling, and ocean biology. The objective of this paper is to propose a new tailings disposal procedure for the deep sea mining industry. Through comparisons of the tailings disposal methods which exist in on-land mining and the coastal mining fields, a new tailings disposal procedure, i.e., the submarine–backfill–dam–reuse (SBDR) tailings disposal procedure, is proposed. It com...

  18. CT of the canine lumbosacral spine in extension - flexion rotation; part I: bony window

    International Nuclear Information System (INIS)

    Henninger, W.; Werner, G.

    2002-01-01

    The canine lumbosacral spine is examined radiographically in extended and flexed lateral position as well as ventrodorsally. Superimposition of bones hinders exact evaluation of the lumbosacral intervertebral foramen in case of cauda equina syndrome, especially when degenerative changes overlap. CT or MRI are more and more indicated to get reliable findings because myelography is not always of diagnostic value. For this study twelve dogs (7 German Shepherd dogs, 4 Cross-breds, and 1 Rottweiler) of different age and sex were taken which had been referred for CT examination of the lumbosacral area. Plain radiographs did not show abnormalities. The anaesthetized dogs were positioned in dorsal recumbency with the legs firstly extended and secondly flexed according to flexion-extension radiography. Slice thickness was 2 mm, the CT images were evaluated in both bony and soft tissue windows. Bony window easily showed vertebral bodies, vertebral canal, pedicles, vertebral laminae, and articular processes of L7 and S1. Median height of the vertebral canal did not change during extension or flexion at the level of L7 and the sacrum. Height and width of the intervertebral foramen and width of the interarcual foramen changed markedly from extension to flexion. Lateral recessus of the vertebral canal always could be observed as ventrolateral widening. In sagittal CT scans of the lumbosacral specimen of a normal German Shepherd dog cranial articular processes of the sacrum were detected to be responsible for maximum height or width of the intervertebral foramen. Evolving from the lateral recessus the intervertebral foramen was initially oval-shaped and got rounded and narrowed by the cranial articular process of the sacrum. Position and shape of the cranial articular processes of the sacrum were evaluated. Surface of the cranial articular processes of S1 were found even with articular spaces congruent, but some also appeared slightly concave or convex where incongruity of the

  19. Effects of tail docking and docking length on neuroanatomical changes in healed tail tips of pigs

    DEFF Research Database (Denmark)

    Herskin, M S; Thodberg, K; Jensen, Henrik Elvang

    2015-01-01

    % (n=19); or leaving 25% (n=11) of the tail length on the pigs. The piglets were docked between day 2 and 4 after birth using a gas-heated apparatus, and were kept under conventional conditions until slaughter at 22 weeks of age, where tails were removed and examined macroscopically and histologically...

  20. Tail Asymptotics for the Sum of two Heavy-tailed Dependent Risks

    DEFF Research Database (Denmark)

    Albrecher, H.; Asmussen, Søren

    Let X1,X2 denote positive exchangable heavy-tailed random variables with continuous marginal distribution function F. The asymptotic behavior of the tail of X1 + X2 is studied in a general copula framework and some bounds and extremal properties are provided. For more specific assumptions on F...

  1. Tailings neutralization and other alternatives for immobilizing toxic materials in tailings. Final report

    International Nuclear Information System (INIS)

    Opitz, B.E.; Sherwood, D.R.; Dodson, M.E.; Serne, R.J.

    1985-09-01

    This document, ''Tailing Neutralization and Other Alternatives for Immobilizing Toxic Materials in Tailings,'' is the final report in a series of six. It summarizes research completed since the beginning of the project. Three subtasks are included: Subtask A - Neutralization Methods Selection; Subtask B - Laboratory Analysis; and Subtask C - Field Testing. Subtask A reviews treatment processes from other industries to evaluate whether current waste technology from other fields is applicable to the uranium industry. This task also identifies several reagents that were tested for their effectiveness in treating acidic tailings and tailings solution in order to immobilize the contaminants associated with the acid waste. Subtask B describes the laboratory batch and column treatment studies performed on solid waste tailings and tailings solutions over the course of the project. The evaluation of several reagents identified in Subtask A was based on three criteria: (1) treated effluent water quality; (2) neutralized sludge handling and hydraulic properties; and (3) reagent costs and acid neutralizing efficiency. Subtask C presents a field demonstration plan that will evaluate the effectiveness, costs, and benefits of neutralizing acidic uranium mill tailings solution to reduce the potential leaching of toxic trace metals, radionuclides, and macro ions from a tailings impoundment. Details of the related research can be found in the documents listed in the ''Previous Documents in Series.'' 43 refs., 9 figs., 46 tabs

  2. Attitudes of Dutch Pig Farmers Towards Tail Biting and Tail Docking

    NARCIS (Netherlands)

    Bracke, M.B.M.; Lauwere, de C.C.; Wind, S.M.M.; Zonderland, J.J.

    2013-01-01

    The Dutch policy objective of a fully sustainable livestock sector without mutilations by 2023 is not compatible with the routine practice of tail docking to minimize the risk of tail biting. To examine farmer attitudes towards docking, a telephone survey was conducted among 487 conventional and 33

  3. Peculiarities of lens and tail regeneration detected in newts after spaceflight aboard Foton M3

    Science.gov (United States)

    Grigoryan, Eleonora N.; Almeida, Eduardo; Poplinskaya, Valentina; Novikova, Julia; Domaratskaya, Elena; Aleinikova, Karina; Souza, Kenneth; Skidmore, Mike; Grigoryan, Eleonora N.

    In September 2007 the joint, 12 day long experiment was carried out aboard Russian satellite Foton M3. The goal of the experiment was to study eye lens, tail and forelimb toe regeneration in adult 16 newts (Pl. waltl.) operated 10 days before taking-off. In spaceflight and synchronous ground control we used video recording, temperature and irradiation control, as well as constant availability of thymidine analog BrdU for its absorption via animals' skin. New techniques allowed us to analyze animals' behavior in hyperand microgravity periods of time, to take proper account of spaceflight factors, and measure accumulated pools of DNA-synthesizing cells in regenerating tissues. All tissue specimens obtained from animals were isolated in the day of landing and then prepared for morphological, immunochemical and molecular investigations. Synchronous control was shifted for two days and reproduced flight conditions except changes of gravity influence. As a result in flown animals as compared with synchronous ground control we found lens regeneration of 0.5-1 stage speeded up and an increased BrdU+ (S-phase) cell number in eye cornea, growth zone, limbus and newly forming lens. These features of regeneration were accompanied by an increase of FGF2 expression in eye growth zone and heat shock protein (HSP90) induction purely in retinal macroglial cells of regenerating eyes. Toe regeneration rate was equal and achieved the stage of accomplished healing of amputation area in both groups - "flown" and control animals. We found no essential differences in tail regeneration rate and tail regenerate sizes in the newts exposed to space and on ground. In both groups tail regeneration reached the stage IV-V when tail length and square were around 4.4 mm and 15.5 mm2, correspondingly. However we did observe remarkable changes of tail regenerate form and some of pigmentation. Computer morphometrical analysis showed that only in ground control animals the evident dorso

  4. Modification of Spastic Stretch Reflexes at the Elbow by Flexion Synergy Expression in Individuals With Chronic Hemiparetic Stroke.

    Science.gov (United States)

    McPherson, Jacob G; Stienen, Arno H; Drogos, Justin M; Dewald, Julius P

    2018-03-01

    To systematically characterize the effect of flexion synergy expression on the manifestation of elbow flexor stretch reflexes poststroke, and to relate these findings to elbow flexor stretch reflexes in individuals without neurologic injury. Controlled cohort study. Academic medical center. Participants (N=20) included individuals with chronic hemiparetic stroke (n=10) and a convenience sample of individuals without neurologic or musculoskeletal injury (n=10). Participants with stroke were interfaced with a robotic device that precisely manipulated flexion synergy expression (by regulating shoulder abduction loading) while delivering controlled elbow extension perturbations over a wide range of velocities. This device was also used to elicit elbow flexor stretch reflexes during volitional elbow flexor activation, both in the cohort of individuals with stroke and in a control cohort. In both cases, the amplitude of volitional elbow flexor preactivation was matched to that generated involuntarily during flexion synergy expression. The amplitude of short- and long-latency stretch reflexes in the biceps brachii, assessed by electromyography, and expressed as a function of background muscle activation and stretch velocity. Increased shoulder abduction loading potentiated elbow flexor stretch reflexes via flexion synergy expression in the paretic arm. Compared with stretch reflexes in individuals without neurologic injury, paretic reflexes were larger at rest but were approximately equal to control muscles at matched levels of preactivation. Because flexion synergy expression modifies stretch reflexes in involved muscles, interventions that reduce flexion synergy expression may confer the added benefit of reducing spasticity during functional use of the arm. Copyright © 2017 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  5. Posterior tibial slope impacts intraoperatively measured mid-flexion anteroposterior kinematics during cruciate-retaining total knee arthroplasty.

    Science.gov (United States)

    Dai, Yifei; Cross, Michael B; Angibaud, Laurent D; Hamad, Cyril; Jung, Amaury; Jenny, Jean-Yves

    2018-02-23

    Posterior tibial slope (PTS) for cruciate-retaining (CR) total knee arthroplasty (TKA) is usually pre-determined by the surgeon. Limited information is available comparing different choices of PTS on the kinematics of the CR TKA, independent of the balancing of the extension gap. This study hypothesized that with the same balanced extension gap, the choice of PTS significantly impacts the intraoperatively measured kinematics of CR TKA. Navigated CR TKAs were performed on seven fresh-frozen cadavers with healthy knees and intact posterior cruciate ligament (PCL). A custom designed tibial baseplate was implanted to allow in situ modification of the PTS, which altered the flexion gap but maintained the extension gap. Knee kinematics were measured by performing passive range of motion (ROM) tests from full extension to 120° of flexion on the intact knee and CR TKAs with four different PTSs (1°, 4°, 7°, and 10°). The measured kinematics were compared across test conditions to assess the impact of PTS. With a consistent extension gap, the change of PTS had significant impact on the anteroposterior (AP) kinematics of the CR TKA knees in mid-flexion range (45°-90°), but not so much for the high-flexion range (90°-120°). No considerable impacts were found on internal/external (I/E) rotation and hip-knee-ankle (HKA) angle. However, the findings on the individual basis suggested the impact of PTS on I/E rotation and HKA angle may be patient-specific. The data suggested that the choice of PTS had the greatest impact on the mid-flexion AP translation among the intraoperatively measured kinematics. This impact may be considered while making surgical decisions in the context of AP kinematics. When using a tibial component designed with "center" pivoting PTS, a surgeon may be able to fine tune the PTS to achieve proper mid-flexion AP stability.

  6. A nonluminescent and highly virulent Vibrio harveyi strain is associated with "bacterial white tail disease" of Litopenaeus vannamei shrimp.

    Directory of Open Access Journals (Sweden)

    Junfang Zhou

    Full Text Available Recurrent outbreaks of a disease in pond-cultured juvenile and subadult Litopenaeus vannamei shrimp in several districts in China remain an important problem in recent years. The disease was characterized by "white tail" and generally accompanied by mass mortalities. Based on data from the microscopical analyses, PCR detection and 16S rRNA sequencing, a new Vibrio harveyi strain (designated as strain HLB0905 was identified as the etiologic pathogen. The bacterial isolation and challenge tests demonstrated that the HLB0905 strain was nonluminescent but highly virulent. It could cause mass mortality in affected shrimp during a short time period with a low dose of infection. Meanwhile, the histopathological and electron microscopical analysis both showed that the HLB0905 strain could cause severe fiber cell damages and striated muscle necrosis by accumulating in the tail muscle of L. vannamei shrimp, which led the affected shrimp to exhibit white or opaque lesions in the tail. The typical sign was closely similar to that caused by infectious myonecrosis (IMN, white tail disease (WTD or penaeid white tail disease (PWTD. To differentiate from such diseases as with a sign of "white tail" but of non-bacterial origin, the present disease was named as "bacterial white tail disease (BWTD". Present study revealed that, just like IMN and WTD, BWTD could also cause mass mortalities in pond-cultured shrimp. These results suggested that some bacterial strains are changing themselves from secondary to primary pathogens by enhancing their virulence in current shrimp aquaculture system.

  7. Blast densification trials for oilsands tailings

    Energy Technology Data Exchange (ETDEWEB)

    Port, A. [Klohn Crippen Berger Ltd., Vancouver, BC (Canada); Martens, S. [Klohn Crippen Berger Ltd., Calgary, AB (Canada); Eaton, T. [Shell Canada Ltd., Calgary, AB (Canada)

    2010-07-01

    The Shell Canada Muskeg River Mine External Tailings Facility (ETF) is an upstream constructed tailings facility located near Fort McMurray, Alberta. Raises have incrementally stepped out over the beach since construction of the starter dam and deposition within standing water has left some parts of the beach in a loose state. In order to assess the effectiveness of blast densification, a blast densification trial program that was conducted in 2006 at the ETF. The primary purpose of the test program was to determine the effectiveness of blast densification in tailings containing layers and zones of bitumen. The paper described the site characterization and explosive compaction trial program, with particular reference to test layout; drilling methodology; and blasting and timing sequence. The paper also described the instrumentation, including the seismographs; high pressure electric piezometers; low pressure electric piezometers; vibrating wire piezometers; inclinometers; settlement gauges; and surveys. Trial observations and post-trial observations were also presented. It was concluded that controlled blasting techniques could be used to safely induce liquefaction in localized areas within the tailings deposit, with a resulting increase in the tailings density. 5 refs., 1 tab., 14 figs.

  8. Reclamation plans at uranium mill tailings sites

    International Nuclear Information System (INIS)

    Abt, S.R.; Nelson, J.D.

    1990-01-01

    Long-term stability of waste impoundments is of concern because of the long time periods over which various types of waste may remain active. Over the past decade much technology has been developed specifically for reclamation of uranium mill tailings impoundments. Aspects of this technology will be discussed here and is presented as also being directly applicable to reclamation of industrial waste impoundments in general. The paper discusses Title I and Title II sites which represent two different generations in uranium tailings impoundment construction. The comparison between the two represent differences in philosophies as well as in impoundment type. Reclamation of uranium mill tailings impoundments in the U.S. is controlled by Federal legislation, which has set forth the regulatory framework for reclamation plan approval. Title I requirements govern government owned inactive sites and Title II requirements govern active tailings impoundments or those operated by private industries. While the Title I and Title II designation may result in a slightly different regulatory process, reclamation of uranium tailings sites has the same. Differences between Title I and Title II reclamation plans to achieve surface stability relate primarily to the embankment and surface covers. The differences in the cover designs result from site-specific conditions, rather than from differences in engineering approaches or the regulatory process. This paper discusses the site-specific conditions that affect the selection of cover designs, and provides a comparative example to illustrate the effect of this condition

  9. Assessment of the underground disposal of tailings

    Energy Technology Data Exchange (ETDEWEB)

    Hutt, N M [Morwijk Enterprises Ltd., (Canada); Morin, K A [Normar Enterprises, (Canada)

    1995-06-01

    The Atomic Energy Control Board (AECB) of Canada is facing the issue of long-term disposal of uranium tailings. One option that has not been examined in sufficient detail for the AECB is the retrieval of tailings from surface impoundments and subsequent placement of those tailings in underground workings of mines. This report is structured like a catalogue of facts and information, with each paragraph presenting some concept, concern, theory, or case study involving the retrieval or placement of tailings. All relevant information, findings, interpretations, conclusions, and recommendations gathered during the course of this study are included. The Table of Contents illustrates the striking number of relevant topics and acts like a flowchart or checklist to ensure that an underground-disposal submission by a mining company has addressed relevant topics. This report explains in detail the implications of disturbing surface-impounded tailings for the purpose of placing only some of the volume underground. The cumulative environmental, safety, and monetary liabilities of such a partial scheme can be discouraging in some cases. (author). 244 refs., 47 tabs., 17 figs.

  10. Grouting of uranium mill tailings piles

    International Nuclear Information System (INIS)

    Boegly, W.J. Jr.; Tamura, T.; Williams, J.D.

    1984-03-01

    A program of remedial action was initiated for a number of inactive uranium mill tailings piles. These piles result from mining and processing of uranium ores to meet the nation's defense and nuclear power needs and represent a potential hazard to health and the environment. Possible remedial actions include the application of covers to reduce radon emissions and airborne transport of the tailings, liners to prevent groundwater contamination by leachates from the piles, physical or chemical stabilization of the tailings, or moving the piles to remote locations. Conventional installation of liners would require excavation of the piles to emplace the liner; however, utilization of grouting techniques, such as those used in civil engineering to stabilize soils, might be a potential method of producing a liner without excavation. Laboratory studies on groutability of uranium mill tailings were conducted using samples from three abandoned piles and employing a number of particulate and chemical grouts. These studies indicate that it is possible to alter the permeability of the tailings from ambient values of 10 -3 cm/s to values approaching 10 -7 cm/s using silicate grouts and to 10 -8 cm/s using acrylamide and acrylate grouts. An evaluation of grouting techniques, equipment required, and costs associated with grouting were also conducted and are presented. 10 references, 1 table

  11. Remote sensing to monitor uranium tailing sites

    International Nuclear Information System (INIS)

    1992-02-01

    This report concerns the feasibility of using remotely-sensed data for long-term monitoring of uranium tailings. Decommissioning of uranium mine tailings sites may require long-term monitoring to confirm that no unanticipated release of contaminants occurs. Traditional ground-based monitoring of specific criteria of concern would be a significant expense depending on the nature and frequency of the monitoring. The objective of this study was to evaluate whether available remote-sensing data and techniques were applicable to the long-term monitoring of tailings sites. This objective was met by evaluating to what extent the data and techniques could be used to identify and discriminate information useful for monitoring tailings sites. The cost associated with obtaining and interpreting this information was also evaluated. Satellite and aircraft remote-sensing-based activities were evaluated. A monitoring programme based on annual coverage of Landsat Thematic Mapper data is recommended. Immediately prior to and for several years after decommissioning of the tailings sites, airborne multispectral and thermal infrared surveys combined with field verification data are required in order to establish a baseline for the long-term satellite-based monitoring programme. More frequent airborne surveys may be required if rapidly changing phenomena require monitoring. The use of a geographic information system is recommended for the effective storage and manipulation of data accumulated over a number of years

  12. Assessment of the underground disposal of tailings

    International Nuclear Information System (INIS)

    Hutt, N.M.; Morin, K.A.

    1995-06-01

    The Atomic Energy Control Board (AECB) of Canada is facing the issue of long-term disposal of uranium tailings. One option that has not been examined in sufficient detail for the AECB is the retrieval of tailings from surface impoundments and subsequent placement of those tailings in underground workings of mines. This report is structured like a catalogue of facts and information, with each paragraph presenting some concept, concern, theory, or case study involving the retrieval or placement of tailings. All relevant information, findings, interpretations, conclusions, and recommendations gathered during the course of this study are included. The Table of Contents illustrates the striking number of relevant topics and acts like a flowchart or checklist to ensure that an underground-disposal submission by a mining company has addressed relevant topics. This report explains in detail the implications of disturbing surface-impounded tailings for the purpose of placing only some of the volume underground. The cumulative environmental, safety, and monetary liabilities of such a partial scheme can be discouraging in some cases. (author). 244 refs., 47 tabs., 17 figs

  13. Insights into Head-Tailed Viruses Infecting Extremely Halophilic Archaea

    Science.gov (United States)

    Pietilä, Maija K.; Laurinmäki, Pasi; Russell, Daniel A.; Ko, Ching-Chung; Jacobs-Sera, Deborah; Butcher, Sarah J.

    2013-01-01

    Extremophilic archaea, both hyperthermophiles and halophiles, dominate in habitats where rather harsh conditions are encountered. Like all other organisms, archaeal cells are susceptible to viral infections, and to date, about 100 archaeal viruses have been described. Among them, there are extraordinary virion morphologies as well as the common head-tailed viruses. Although approximately half of the isolated archaeal viruses belong to the latter group, no three-dimensional virion structures of these head-tailed viruses are available. Thus, rigorous comparisons with bacteriophages are not yet warranted. In the present study, we determined the genome sequences of two of such viruses of halophiles and solved their capsid structures by cryo-electron microscopy and three-dimensional image reconstruction. We show that these viruses are inactivated, yet remain intact, at low salinity and that their infectivity is regained when high salinity is restored. This enabled us to determine their three-dimensional capsid structures at low salinity to a ∼10-Å resolution. The genetic and structural data showed that both viruses belong to the same T-number class, but one of them has enlarged its capsid to accommodate a larger genome than typically associated with a T=7 capsid by inserting an additional protein into the capsid lattice. PMID:23283946

  14. Will Culling White-Tailed Deer Prevent Lyme Disease?

    Science.gov (United States)

    Kugeler, K J; Jordan, R A; Schulze, T L; Griffith, K S; Mead, P S

    2016-08-01

    White-tailed deer play an important role in the ecology of Lyme disease. In the United States, where the incidence and geographic range of Lyme disease continue to increase, reduction of white-tailed deer populations has been proposed as a means of preventing human illness. The effectiveness of this politically sensitive prevention method is poorly understood. We summarize and evaluate available evidence regarding the effect of deer reduction on vector tick abundance and human disease incidence. Elimination of deer from islands and other isolated settings can have a substantial impact on the reproduction of blacklegged ticks, while reduction short of complete elimination has yielded mixed results. To date, most studies have been conducted in ecologic situations that are not representative to the vast majority of areas with high human Lyme disease risk. Robust evidence linking deer control to reduced human Lyme disease risk is lacking. Currently, there is insufficient evidence to recommend deer population reduction as a Lyme disease prevention measure, except in specific ecologic circumstances. © 2015 Blackwell Verlag GmbH.

  15. Spontaneous Improvement of Compensatory Knee Flexion After Surgical Correction of Mismatch Between Pelvic Incidence and Lumbar Lordosis.

    Science.gov (United States)

    Cheng, Xiaofei; Zhang, Feng; Wu, Jigong; Zhu, Zhenan; Dai, Kerong; Zhao, Jie

    2016-08-15

    A retrospective study. The aim of this study was to investigate the correlation between pelvic incidence (PI) and lumbar lordosis (LL) mismatch and knee flexion during standing in patients with lumbar degenerative diseases and to examine the effects of surgical correction of the PI-LL mismatch on knee flexion. Only several studies focused on knee flexion as a compensatory mechanism of the PI-LL mismatch. Little information is currently available on the effects of lumbar correction on knee flexion in patients with the PI-LL mismatch. A group of patients with lumbar degenerative diseases were divided into PI-LL match group (PI-LL ≤ 10°) and PI-LL mismatch group (PI-LL > 10°). A series of radiographic parameters and knee flexion angle (KFA) were compared between the two groups. The PI-LL mismatch group was further subdivided into operative and nonoperative group. The changes in KFA with PI-LL were examined. The PI-LL mismatch group exhibited significantly greater sagittal vertical axis (SVA), pelvic tilt (PT) and KFA, and smaller LL, thoracic kyphosis (TK), and sacral slope than the PI-LL match group. PI-LL, LL, PI, SVA, and PT were significantly correlated with KFA in the PI-LL mismatch group. From baseline to 6-month follow-up, all variables were significantly different in the operative group with the exception of PI, although there was no significant difference in any variable in the nonoperative group. The magnitude of surgical correction in the PI-LL mismatch was significantly correlated with the degree of spontaneous changes in KFA, PT, and TK. The PI-LL mismatch would contribute to compensatory knee flexion during standing in patients with lumbar degenerative disease. Surgical correction of the PI-LL mismatch could lead to a spontaneous improvement of compensatory knee flexion. The degree of improvement in knee flexion depends in part on the amount of correction in the PI-LL mismatch. 3.

  16. Does rehabilitation of cervical lordosis influence sagittal cervical spine flexion extension kinematics in cervical spondylotic radiculopathy subjects?

    Science.gov (United States)

    Moustafa, Ibrahim Moustafa; Diab, Aliaa Attiah Mohamed; Hegazy, Fatma A; Harrison, Deed E

    2017-01-01

    To test the hypothesis that improvement of cervical lordosis in cervical spondylotic radiculopathy (CSR) will improve cervical spine flexion and extension end range of motion kinematics in a population suffering from CSR. Thirty chronic lower CSR patients with cervical lordosis lordosis (p lordosis in the study group was associated with significant improvement in the translational and rotational motions of the lower cervical spine. This finding provides objective evidence that cervical flexion/extension is partially dependent on the posture and sagittal curve orientation. These findings are in agreement with several other reports in the literature; whereas ours is the first post treatment analysis identifying this relationship.

  17. A restrained-torque-based motion instructor: forearm flexion/extension-driving exoskeleton

    Science.gov (United States)

    Nishimura, Takuya; Nomura, Yoshihiko; Sakamoto, Ryota

    2013-01-01

    When learning complicated movements by ourselves, we encounter such problems as a self-rightness. The self-rightness results in a lack of detail and objectivity, and it may cause to miss essences and even twist the essences. Thus, we sometimes fall into the habits of doing inappropriate motions. To solve these problems or to alleviate the problems as could as possible, we have been developed mechanical man-machine human interfaces to support us learning such motions as cultural gestures and sports form. One of the promising interfaces is a wearable exoskeleton mechanical system. As of the first try, we have made a prototype of a 2-link 1-DOF rotational elbow joint interface that is applied for teaching extension-flexion operations with forearms and have found its potential abilities for teaching the initiating and continuing flection motion of the elbow.

  18. flexion sur l’origine du processus de segmentation du marche du travail

    Directory of Open Access Journals (Sweden)

    Attia Nicole

    2006-01-01

    Full Text Available (francuski Ce travail propose une réflexion sur l'origine du processus de segmentation du marché du travail par rapport à l'entreprise. Se situe-t-elle au sein même de l'entreprise ou en amont, c'est à dire entre les entreprises? Cela revient à se demander si on peut avoir une approche microéconomique ou macroéconomique de la segmentation et, à s'interroger sur le rôle réel tenu par les firmes dans le processus. Déterminant pour la théorie, ce rôle est à repenser selon la réponse apportée à notre question.

  19. Evaluation experimentale et theorique du comportement a la flexion de nouveaux poteaux en materiaux composites

    Science.gov (United States)

    Metiche, Slimane

    La demande croissante en poteaux pour les differents reseaux d'electricite et de telecommunications a rendu necessaire l'utilisation de materiaux innovants, qui preservent l'environnement. La majorite des poteaux electriques existants au Canada ainsi qu'a travers le monde, sont fabriques a partir de materiaux traditionnels tel que le bois, le beton ou l'acier. Les motivations des industriels et des chercheurs a penser a d'autres solutions sont diverses, citons entre autre: La limitation en longueur des poteaux en bois ainsi que la vulnerabilite des poteaux fabriques en beton ou en acier aux agressions climatiques. Les nouveaux poteaux en materiaux composites se presentent comme de bons candidats a cet effet, cependant; leur comportement structural n'est pas connu et des etudes theoriques et experimentales approfondies sont necessaires avant leur mise en marche a grande echelle. Un programme de recherche intensif comportant plusieurs projets experimentaux, analytiques et numeriques est en cours a l'Universite de Sherbrooke afin d'evaluer le comportement a court et a long termes de ces nouveaux poteaux en Polymeres Renforces de Fibres (PRF). C'est dans ce contexte que s'inscrit la presente these, et notre recherche vise a evaluer le comportement a la flexion de nouveaux poteaux tubulaires coniques fabriques en materiaux composites par enroulement filamentaire et ce, a travers une etude theorique, ainsi qu'a travers une serie d'essais de flexion en "grandeur reelle" afin de comprendre le comportement structural de ces poteaux, d'optimiser la conception et de proposer une procedure de dimensionnement pour les utilisateurs. Les poteaux en Polymeres Renforces de Fibres (PRF) etudies dans cette these sont fabriques avec une resine epoxyde renforcee de fibres de verre type E. Chaque type poteaux est constitue principalement de trois zones ou les proprietes geometriques (epaisseur, diametre) et les proprietes mecaniques sont differentes d'une zone a l'autre. La difference

  20. Quasi-stiffness of the knee joint in flexion and extension during the golf swing.

    Science.gov (United States)

    Choi, Ahnryul; Sim, Taeyong; Mun, Joung Hwan

    2015-01-01

    Biomechanical understanding of the knee joint during a golf swing is essential to improve performance and prevent injury. In this study, we quantified the flexion/extension angle and moment as the primary knee movement, and evaluated quasi-stiffness represented by moment-angle coupling in the knee joint. Eighteen skilled and 23 unskilled golfers participated in this study. Six infrared cameras and two force platforms were used to record a swing motion. The anatomical angle and moment were calculated from kinematic and kinetic models, and quasi-stiffness of the knee joint was determined as an instantaneous slope of moment-angle curves. The lead knee of the skilled group had decreased resistance duration compared with the unskilled group (P golf swing and developing rehabilitation strategies following surgery.

  1. Bethlem myopathy: An autosomal dominant myopathy with flexion contractures, keloids, and follicular hyperkeratosis.

    Science.gov (United States)

    Saroja, Aralikatte Onkarappa; Naik, Karkal Ravishankar; Nalini, Atcharayam; Gayathri, Narayanappa

    2013-10-01

    Bethlem myopathy and Ullrich congenital muscular dystrophy form a spectrum of collagenopathies caused by genetic mutations encoding for any of the three subunits of collagen VI. Bethlem phenotype is relatively benign and is characterized by proximal dominant myopathy, keloids, contractures, distal hyperextensibility, and follicular hyperkeratosis. Three patients from a single family were diagnosed to have Bethlem myopathy based on European Neuromuscular Centre Bethlem Consortium criteria. Affected father and his both sons had slowly progressive proximal dominant weakness and recurrent falls from the first decade. Both children aged 18 and 20 years were ambulant at presentation. All had flexion contractures, keloids, and follicular hyperkeratosis without muscle hypertrophy. Creatinine kinase was mildly elevated and electromyography revealed myopathic features. Muscle imaging revealed severe involvement of glutei and vasti with "central shadow" in rectus femoris. Muscle biopsy in the father showed dystrophic changes with normal immmunostaining for collagen VI, sarcoglycans, and dysferlin.

  2. Bethlem myopathy: An autosomal dominant myopathy with flexion contractures, keloids, and follicular hyperkeratosis

    Directory of Open Access Journals (Sweden)

    Aralikatte Onkarappa Saroja

    2013-01-01

    Full Text Available Bethlem myopathy and Ullrich congenital muscular dystrophy form a spectrum of collagenopathies caused by genetic mutations encoding for any of the three subunits of collagen VI. Bethlem phenotype is relatively benign and is characterized by proximal dominant myopathy, keloids, contractures, distal hyperextensibility, and follicular hyperkeratosis. Three patients from a single family were diagnosed to have Bethlem myopathy based on European Neuromuscular Centre Bethlem Consortium criteria. Affected father and his both sons had slowly progressive proximal dominant weakness and recurrent falls from the first decade. Both children aged 18 and 20 years were ambulant at presentation. All had flexion contractures, keloids, and follicular hyperkeratosis without muscle hypertrophy. Creatinine kinase was mildly elevated and electromyography revealed myopathic features. Muscle imaging revealed severe involvement of glutei and vasti with "central shadow" in rectus femoris. Muscle biopsy in the father showed dystrophic changes with normal immmunostaining for collagen VI, sarcoglycans, and dysferlin.

  3. MR imaging and radiography of patients with cervical hyperextension-flexion injuries after car accidents

    Energy Technology Data Exchange (ETDEWEB)

    Borchgrevink, G E [The Emergency Clinic, Trondheim Univ. Hospital (Norway); Smevik, O [MR-Centre Medical Section, Trondheim Univ. Hospital (Norway); Nordby, A [Dept. of Radiology, Trondheim Univ. Hospital (Norway); Rinck, P A [MR-Centre Medical Section, Trondheim Univ. Hospital (Norway); Stiles, T C [Dept. of Psychiatry and Behavioural Medicine, Trondheim Univ. (Norway); Lereim, I [The Emergency Clinic, Trondheim Univ. Hospital (Norway)

    1995-07-01

    Fifty-two patients underwent MR imaging and conventional radiography of the neck within 4 days after a hyperextension-flexion injury. The patients also had follow-up investigations during the first 2 years. The images did not reveal any serious lesions in any of them. Based on the main MR and radiographical findings the patients were divided into 4 groups; no findings, posture abnormalities, spondylosis and disc pathology (from MR images) or reduced intervertebral space (from the radiographs). The outcomes of the different groups were compared with reference to neck stiffness, neck pain and headache during a 2-year follow-up period. The patient groups did not correspond completely when diagnosed from MR imaging and radiography. However, patients with pre-existing spondylosis had more symptoms when examined by both modalities. Based on the radiographs, the group with posture abnormalities had significant fewer symptoms than the other groups. (orig.).

  4. Mechanical Simulation of the Extension and Flexion of the Elbow Joint in Rehabilitation

    Directory of Open Access Journals (Sweden)

    Iman Vahdat

    2013-01-01

    Full Text Available Objective: The goal of the present study was to improve the extension and flexion of the elbow joint for rehabilitation purposes, in terms of energy dissipation and of injuries caused by stress imposed on connective tissue by exercise equipments during force transfer , by investigation of viscoelastic property variations during change in speed of motion. Materials & Methods: A sample of five men without any previous neuromuscular impairment of the elbow joint was chosen by the BMI factor. The passive continuous motion test (CPM was performed by the CYBEX isokinetic system in the extension and flexion movements of the elbow joint of the left hand, at 4 different speeds (15, 45, 75 and120 Deg/s during 5 consecutive cycles at the range of motion of about 0 to 130 degrees. The experimental data was exported to the MATLAB software for analysis. In order to determine viscoelastic property effects and biomechanical parameters, we used a passive viscoelastic mechanical model constructed by 3 elements for simulation, and also we used the curve fitting method to derive the elastic and viscose coefficients for the model.,. Results: Results of experiments showed that by increasing the speed of motion, the value of work done, hysteresis and elastic coefficient increased and the value of viscose coefficient decreased. Also, it appeared that by increasing the speed of motion, the effect of viscose resistance on the passive torque curves increased. In addition, there was significant correlation between the action of the mechanical model and the action of the concerned limbs, during the movement. Conclusion: It was concluded that in order to improve motion and to reduce imposed risks and injuries to joints and limbs, rehabilitation exercises better be performed at lower speeds and with rehabilitation equipments supported by viscoelastic resistant force.

  5. Comparison of tibiofemoral joint space width measurements from standing CT and fixed flexion radiography.

    Science.gov (United States)

    Segal, Neil A; Frick, Eric; Duryea, Jeffrey; Nevitt, Michael C; Niu, Jingbo; Torner, James C; Felson, David T; Anderson, Donald D

    2017-07-01

    The objective of this project was to determine the relationship between medial tibiofemoral joint space width measured on fixed-flexion radiographs and the three-dimensional joint space width distribution on low-dose, standing CT (SCT) imaging. At the 84-month visit of the Multicenter Osteoarthritis Study, 20 participants were recruited. A commercial SCT scanner for the foot and ankle was modified to image knees while standing. Medial tibiofemoral joint space width was assessed on radiographs at fixed locations from 15% to 30% of compartment width using validated software and on SCT by mapping the distances between three-dimensional subchondral bone surfaces. Individual joint space width values from radiographs were compared with three-dimensional joint space width values from corresponding sagittal plane locations using paired t-tests and correlation coefficients. For the four medial-most tibiofemoral locations, radiographic joint space width values exceeded the minimal joint space width on SCT by a mean of 2.0 mm and were approximately equal to the 61st percentile value of the joint space width distribution at each respective sagittal-plane location. Correlation coefficients at these locations were 0.91-0.97 and the offsets between joint space width values from radiographs and SCT measurements were consistent. There were greater offsets and variability in the offsets between modalities closer to the tibial spine. Joint space width measurements on fixed-flexion radiographs are highly correlated with three-dimensional joint space width from SCT. In addition to avoiding bony overlap obscuring the joint, a limitation of radiographs, the current study supports a role for SCT in the evaluation of tibiofemoral OA. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1388-1395, 2017. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  6. The flexion synergy, mother of all synergies and father of new models of gait

    Directory of Open Access Journals (Sweden)

    Jacques eDuysens

    2013-03-01

    Full Text Available Recently there has been a growing interest in the modular organization of leg movements, in particular those related to locomotion. One of the basic modules involves the flexion of the leg during swing and it was shown that this module is already present in neonates (Dominici, et al. 2011. In this paper, we question how these finding build upon the original work by Sherrington, who proposed that the flexor reflex is the basic building block of the flexion during swing phase. Similarly, the relation between the flexor reflex and the withdrawal reflex modules of Schouenborg et al. (1994 will be discussed. It will be argued that there is large overlap between these notions on modules and the older concepts of reflexes. In addition, it will be shown that there is a great flexibility in the expression of some of these modules during gait, thereby allowing for a phase-dependent modulation of the appropriate responses. In particular, the end of the stance phase is a period when the flexor synergy is facilitated. It is proposed that this is linked to the activation of circuitry that is responsible for the generation of locomotor patterns (CPG, central pattern generator. More specifically, it is suggested that the responses in that period relate to the activation of a flexor burst generator. The latter structure forms the core of a new asymmetric model of the CPG. This activation is controlled by afferent input (facilitation by a broad range of afferents, suppression by load afferent input. Meanwhile, many of these physiologic features have found their way in the control of very flexible walking bipedal robots.

  7. Oil sands tailings preliminary ecological risk assessment

    International Nuclear Information System (INIS)

    1994-01-01

    Chemical data collected from various oil sands soil-tailings mixtures were used to determine the ecological risk that such tailings would pose to terrestrial wildlife at the surface of a reclaimed site. A methodology that could be used to evaluate the risks posed by various reclamation options (for dry land only) was proposed. Risks associated with other reclamation options, such as wet landscapes or deeper in-pit disposal, were not evaluated. Ten constituents (eight organic and two inorganic) were found to pose a threat to terrestrial biota. The relative contribution of different exposure pathways (water and food ingestion, incidental soil ingestion, inhalation) were studied by probabilistic models. Some physical and chemical reclamation alternatives which involve incorporating oil sands tailings in the landscape to produce a surface that could sustain a productive ecosystem, were described. 53 refs., 15 tabs., 3 figs

  8. Uranium tailings in the public eye

    International Nuclear Information System (INIS)

    Lyon, B.

    1976-01-01

    The ORNL field team visits to Grand Junction, Colorado, and to other sources of uranium mill tailings, are described. The radioactive hazards of these tailings, which are principally due to Th, Ra, Rn, and radon daughters, are discussed briefly. Government actions which were taken as a result of public concern are listed. The ORNL Health Physics Division mobile laboratory van and its use in assessing the tailings piles at Salt Lake City and elsewhere are described. The highest γ-ray background found was 155 mRem/y, with levels being as high as 1750 mRem/y near points of public access to piles. Some possible solutions to the problem are discussed

  9. Tree growth studies on uranium mill tailings

    International Nuclear Information System (INIS)

    Murray, D.R.; Turcotte, M.

    1982-01-01

    Coniferous trees planted in 1974 and deciduous species that have volunteered since 1970 on uranium mill tailings that had been stabilized to varying degrees using limestone and vegetation were evaluated. Their survival and growth rates were compared with those from other investigations. Competition for light appears to be a major contributor to mortality. Differences in soil moisture conditions under a tree stand as compared to those under a grass sward are potentially significant enough to affect the tailings hydrology and effluent contamination. Recommendations include planting seeds of deciduous species or deciduous and coniferous seedlings on strips of freshly disturbed tailings. The disturbed strips would provide reduced competition for the initial year and assist in tree survival. The planting of block stands of coniferous or deciduous trees would be useful for evaluating the hydrological impact of the trees as compared to the present grass sward

  10. Optimization of uranium mill tailings disposal practices

    International Nuclear Information System (INIS)

    Richardson, Allan C.B.; Rowe, William D.

    1984-01-01

    So far as we have been to discern, no uranium mill tailings pile has yet been properly stabilized for long-term disposal. And although considerable effort is now being directed at developing practical solutions and at establishing standards for permanent disposal, the difficulties in application are diverse. They arise from the variety of environments in which milling is conducted, the significant costs associated with disposing of the large volumes of materials involved, the diverse nature of the hazards to be protected against, and uncertainties in both performance of controls and in how to determine societal responsibilities for management of the long term hazards to human populations from uranium tailings. There are 24 uranium tailings piles in the United States which no longer have responsible owners, and must now be disposed of by the U.S. Government in order to protect public health

  11. Field evaporation test of uranium tailings solution

    International Nuclear Information System (INIS)

    Chandler, B.L.; Shepard, T.A.; Stewart, T.A.

    1985-01-01

    A field experiment was performed to observe the effect on evaporation rate of a uranium tailings impoundment pond water as salt concentration of the water increased. The duration of the experiment was long enough to cause maximum salt concentration of the water to be attained. The solution used in the experiment was tailings pond water from an inactive uranium tailings disposal site in the initial stages of reclamation. The solution was not neutralized. The initial pH was about 1.0 decreasing to a salt gel at the end of the test. The results of the field experiment show a gradual and slight decrease in evaporation efficiency. This resulted as salt concentrations increased and verified the practical effectiveness of evaporation as a water removal method. In addition, the physical and chemical nature of the residual salts suggest that no long-term stability problem would likely result due to their presence in the impoundment during or after reclamation

  12. International experience in tailings pond remediation

    International Nuclear Information System (INIS)

    Robertson, A.MacG.

    2001-01-01

    Tailings pond remediation is required primarily on mine closure. While mining is an ancient industry, requirement for mine facility remediation is a comparatively new development. Requirement for remediation has come about partly as a result of mans awareness of the environmental impacts of mining and his desire to minimize this, partly, as a result of the ever-increasing scale and production rates of tailings generation and the resulting increased environmental impacts and safety risks. The paper starts with a review of the evolution of mans intolerance of environmental impacts from tailings production and the assignment of liability to remediate such impacts. Many of the tailings ponds currently undergoing remediation were designed and constructed using methods and technology that would be considered inappropriate for new impoundments being designed and developed today. The paper reviews the history of tailings impoundment design and construction practice and the resulting inherent deficiencies that must be remediated. Current practices and future trends in tailings pond remediation are reviewed. The evolution of regulatory requirements is not only in terms of technical and safety criteria, but also in terms of financial and political risk. Perhaps the most substantive driver of risk management is today the requirement for corporate governance at mining company board level and oversight of new project development in the underdeveloped countries by the large financial institutions responsible for funding projects. Embarrassment in the public eye and punishment in the stock markets for poor environmental and safety performance is driving the need for efficient and effective risk management of potential impacts and the remediation to avoid these. A basis for practical risk management is described. (orig.)

  13. International experience in tailings pond remediation

    Energy Technology Data Exchange (ETDEWEB)

    MacG. Robertson, A. [Robertson GeoConsultants Ltd., Vancouver (Canada)

    2001-07-01

    Tailings pond remediation is required primarily on mine closure. While mining is an ancient industry, requirement for mine facility remediation is a comparatively new development. Requirement for remediation has come about partly as a result of mans awareness of the environmental impacts of mining and his desire to minimize this, partly, as a result of the ever-increasing scale and production rates of tailings generation and the resulting increased environmental impacts and safety risks. The paper starts with a review of the evolution of mans intolerance of environmental impacts from tailings production and the assignment of liability to remediate such impacts. Many of the tailings ponds currently undergoing remediation were designed and constructed using methods and technology that would be considered inappropriate for new impoundments being designed and developed today. The paper reviews the history of tailings impoundment design and construction practice and the resulting inherent deficiencies that must be remediated. Current practices and future trends in tailings pond remediation are reviewed. The evolution of regulatory requirements is not only in terms of technical and safety criteria, but also in terms of financial and political risk. Perhaps the most substantive driver of risk management is today the requirement for corporate governance at mining company board level and oversight of new project development in the underdeveloped countries by the large financial institutions responsible for funding projects. Embarrassment in the public eye and punishment in the stock markets for poor environmental and safety performance is driving the need for efficient and effective risk management of potential impacts and the remediation to avoid these. A basis for practical risk management is described. (orig.)

  14. Proceedings of the 2. international oil sands tailings conference

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-01

    The tailings produced by oil sands extraction processes pose significant threats to the surrounding environment in addition to releasing greenhouse gases (GHGs) into the atmosphere. Recent directives have been established to reduce the amount of tailings produced at oil sands operations, and to ensure that tailings ponds are reclaimed in the most effective manner. This conference provided a forum for researchers and industry experts to discuss issues related to the management and reclamation of oil sands tailings. New technologies for dewatering tailings ponds were presented, and methods of analyzing the chemical properties of tailings were reviewed. The conference was divided into the following 7 sessions: (1) tailings properties, (2) tailings dewatering, (3) new concepts, (4) water and chemistry, (5) soft tailings stabilization and reclamation, (6) water treatment, and (7) new concepts 2. The conference featured 44 presentations, all of which have been catalogued separately for inclusion in this database. tabs., figs.

  15. Reclamation and closure of an oil sands tailings facility

    Energy Technology Data Exchange (ETDEWEB)

    Sobkowicz, J. [Thurber Engineering Ltd., Calgary, AB (Canada); Morgenstern, N. [Alberta Univ., Edmonton, AB (Canada)

    2010-07-01

    This PowerPoint presentation discussed methods of ensuring the successful reclamation of oil sands tailings facilities. Tailings should be reclaimed as mining proceeds in order to avoid an excessive accumulation of fluid fine tailings (FFT). The volume of mature fine tailings (MFT) in ponds should be limited in order to ensure effective tailings management. The reclaimed landforms should have good geotechnical stability and be comprised of self-sustaining native vegetation. Strength is needed to allow for timely capping and initial reclamation, and stiffness is required to minimize future settlement and to allow for the construction of a closure landscape. Reclamation strategies were presented for fines-dominated tailings; sand-depleted tailings; and sand-dominated tailings. Energy Resources Conservation Board (ERCB) criteria for tailings reclamation were discussed, and various monitoring and performance assessment strategies were presented. tabs., figs.

  16. A guide to the management of tailings facilities

    International Nuclear Information System (INIS)

    Bedard, C.; Ferguson, K.; Gladwin, D.; Lang, D.; Maltby, J.; McCann, M.; Poirier, P.; Schwenger, R.; Vezina, S.; West, S.; Duval, J.; Gardiner, E.; Jansons, K.; Lewis, B.; Matthews, J.; Mchaina, D.; Puro, M.; Siwik, R.; Welch, D.

    1998-01-01

    The 'Guide to the Management of Tailings Facilities' has been developed by the Mining Association of Canada in an effort to provide guidance to its member companies on sound practices for the safe and environmentally responsible management of tailings facilities. The guide is a reference tool to help companies ensure that they are managing their tailings facilities responsibly, integrating environmental and safety considerations in a consistent manner, with continuous improvement in the operation of tailings facilities. The key to managing tailings responsibly is consistent application of engineering capabilities through the full life cycle. The guide provides a basis for the development of customized tailings management systems to address specific needs at individual operations, and deals with environmental impacts, mill tailing characteristics, tailings facility studies and plans, dam and related structure design, and control and monitoring. Aspects relating to tailings facility siting, design, construction, operation, decommissioning and closure are also fully treated. 1 tab., 3 figs

  17. Long term aspects of uranium tailings management

    International Nuclear Information System (INIS)

    Bragg, K.

    1980-05-01

    This paper sets out the background issues which lead to the development of interim close-out criteria for uranium mill tailings. It places the current state-of-the-art for tailings management into both a national and international perspective and shows why such interim criteria are needed now. There are seven specific criteria proposed dealing with the need to have: passive barriers, limits on surface water recharge, durable systems, long term performance guarantees, limits to access, controls on water and airborne releases and finally to have a knowledge of exposure pathways. This paper is intended to serve as a focus for subsequent discussions with all concerned parties. (auth)

  18. Dynamics of Histone Tails within Chromatin

    Science.gov (United States)

    Bernier, Morgan; North, Justin; Page, Michael; Jaroniec, Christopher; Hammel, Christopher; Poirier, Michael

    2012-02-01

    Genetic information in humans is encoded within DNA molecules that is wrapped around histone octamer proteins and compacted into a highly conserved structural polymer, chromatin. The physical and material properties of chromatin appear to influence gene expression by altering the accessibility of proteins to the DNA. The tails of the histones are flexible domains that are thought to play a role in regulating DNA accessibility and compaction; however the molecular mechanisms for these phenomena are not understood. I will present CW-EPR studies on site directed spin labeled nucleosomes that probe the structure and dynamics of these histone tails within nucleosomes.

  19. Containment systems for uranium-mill tailings

    International Nuclear Information System (INIS)

    Hartley, J.N.; Buelt, J.L.

    1982-11-01

    Cover and liner systems for uranium mill tailings in the United States must satisfy stringent requirements regarding long-term stability, radon control, and radionuclide and hazardous chemical migration. The cover and liner technology discussed in this paper involves: (1) single and multilayer earthen cover systems; (2) asphalt emulsion radon barrier systems; and (3) asphalt, clay, and synthetic liner systems. These systems have been field tested at the Grand Junction, Colorado, tailings pile, where they have been shown to effectively reduce radon releases and radionuclide and chemical migration

  20. TIDAL TAILS OF MINOR MERGERS: STAR FORMATION EFFICIENCY IN THE WESTERN TAIL OF NGC 2782

    Energy Technology Data Exchange (ETDEWEB)

    Knierman, Karen; Scowen, Paul; Jansen, Rolf A. [School of Earth and Space Exploration, Arizona State University, 550 East Tyler Mall, Room PSF-686 (P.O. Box 871404), Tempe, AZ 85287-1404 (United States); Knezek, Patricia M. [WIYN Consortium, Inc., 950 North Cherry Avenue, Tucson, AZ 85719 (United States); Wehner, Elizabeth, E-mail: karen.knierman@asu.edu, E-mail: paul.scowen@asu.edu, E-mail: rolf.jansen@asu.edu, E-mail: pknezek@noao.edu, E-mail: ewehner@haverford.edu [Department of Astronomy, Haverford College, Haverford, PA 19041 (United States)

    2012-04-10

    While major mergers and their tidal debris are well studied, they are less common than minor mergers (mass ratios {approx}< 0.3). The peculiar spiral NGC 2782 is the result of a merger between two disk galaxies with a mass ratio of {approx}4: 1 occurring {approx}200 Myr ago. This merger produced a molecular and H I-rich, optically bright eastern tail and an H I-rich, optically faint western tail. Non-detection of CO in the western tail by Braine et al. suggested that star formation had not yet begun to occur in that tidal tail. However, deep H{alpha} narrowband images show evidence of recent star formation in the western tail. Across the entire western tail, we find the global star formation rate per unit area ({Sigma}{sub SFR}) to be several orders of magnitude less than expected from the total gas density. Together with extended FUV+NUV emission from Galaxy Evolution Explorer along the tail, this indicates a low global star formation efficiency in the tidal tail producing lower mass star clusters. The H II region that we observed has a local (few-kiloparsec scale) {Sigma}{sub SFR} from H{alpha} that is less than that expected from the total gas density, which is consistent with other observations of tidal debris. The star formation efficiency of this H II region inferred from the total gas density is low, but normal when inferred from the molecular gas density. These results suggest the presence of a very small, locally dense region in the western tail of NGC 2782 or of a low-metallicity and/or low-pressure star-forming region.

  1. Gender differences in tibio-femoral kinematics and quadriceps muscle force during weight-bearing knee flexion in vitro.

    Science.gov (United States)

    Wünschel, Markus; Wülker, Nikolaus; Müller, Otto

    2013-11-01

    Females have a higher risk in terms of anterior cruciate ligament injuries during sports than males. Reasons for this fact may be different anatomy and muscle recruitment patterns leading to less protection for the cruciate- and collateral-ligaments. This in vitro study aims to evaluate gender differences in knee joint kinematics and muscle force during weight-bearing knee flexions. Thirty-four human knee specimens (17 females/17 males) were mounted on a dynamic knee simulator. Weight-bearing single-leg knee flexions were performed with different amounts of simulated body weight (BW). Gender-specific kinematics was measured with an ultrasonic motion capture system and different loading conditions were examined. Knee joint kinematics did not show significant differences regarding anteroposterior and medial-lateral movement as well as tibial varus-valgus and internal-external rotation. This applied to all simulated amounts of BW. Simulating 100 N BW in contrast to AF50 led to a significant higher quadriceps overall force in female knees from 45° to 85° of flexion in contrast to BW 50 N. In these female specimens, the quadriceps overall force was about 20 % higher than in male knees being constant in higher flexion angles. It is indicated by our results that in a squatting movement females compared with males produce higher muscle forces, suggesting an increased demand for muscular stabilization, whereas tibio-femoral kinematics was similar for both genders.

  2. Can total knee arthroplasty (TKA) achieve its goal in knee flexion floor activity of Thai Buddhist monks?

    Science.gov (United States)

    Sresuriyasawad, Viriya

    2012-10-01

    To study knee's angulation required for Thai Buddhist monks whose activity based on floor sitting basis. And to identify an inter-observer reliability of knee flexion measurement based on radiologic reading. Descriptive analysis study comprised of measuring bilateral knee flexing angulation in 4 postures of floor activities; kneeling, monk's position in both right and left manner and sit cross-legged position, in 35 Thai Buddhist monks at Priest Hospital using plain radiograph image. The radiograph imaging for each patient was performed by one radiologist and two orthopedics. The measurement result was also analyzed for inter-observer reliability. Mean knee flexion angle in kneel, left monk's position, right monk's position and sit cross-legged postures were 163.21, 146.49, 148.89 and 138.38 degree, respectively. No statistical difference between knee flexion measurements among 3 investigators. Daily floor activity of Thai Buddhist monks need more flexion capacity than that can achieve by total knee arthroplasty instrument using nowadays.

  3. In-situ mechanical behavior and slackness of the anterior cruciate ligament at multiple knee flexion angles

    NARCIS (Netherlands)

    Rachmat, H.H.; Janssen, D.W.; Verkerke, G.J.; Diercks, R.L.; Verdonschot, N.J.J.

    2016-01-01

    In this study the in-situ tensile behavior and slackness of the anterior cruciate ligament (ACL) was evaluated at various knee flexion angles. In four cadaveric knees the ACL was released at the tibial insertion, after which it was re-connected to a tensiometer. After pre-tensioning (10 N) the ACL

  4. Variability of Measurement of Patellofemoral Indices with Knee Flexion and Quadriceps Contraction: An MRI-Based Anatomical Study

    Science.gov (United States)

    Laugharne, Edward; Bali, Navi; Purushothamdas, Sanjay; Almallah, Faris; Kundra, Rik

    2016-01-01

    Purpose The purpose of this study was to investigate the impact of varying knee flexion and quadriceps activity on patellofemoral indices measured on magnetic resonance imaging (MRI). Materials and Methods MRI of the knee was performed in 20 patients for indications other than patellar or patellofemoral pathology. Axial and sagittal sequences were performed in full extension of the knee with the quadriceps relaxed, full extension of the knee with the quadriceps contracted, 30° flexion of the knee with the quadriceps relaxed, and 30° flexion with the quadriceps contracted. Bisect offset, patella tilt angle, Insall-Salvati ratio and Caton-Deschamps index were measured. Results With the knee flexed to 30° and quadriceps relaxed, the mean values of patellar tilt angle, bisect offset, Insall-Salvati ratio and Caton-Deschamps index were all within normal limits. With the knee extended and quadriceps contracted, the mean patellar tilt angle (normal value, patellofemoral indices. MRI taken with the knee in 30° of flexion allows more reliable assessment of the patellofemoral joint and minimises the confounding effect of quadriceps contraction. PMID:27894177

  5. Are neck flexion, neck rotation, and sitting at work risk factors for neck pain? Results of a prospective cohort study

    NARCIS (Netherlands)

    Ariens, G.A.M.; Bongers, P.M.; Douwes, M.; Miedema, M.C.; Hoogendoorn, W.E.; van der Wal, G.; Bouter, L.M.; van Mechelen, W.

    2001-01-01

    Objective: To study the relation between neck pain and work related neck flexion, neck rotation, and sitting. Methods: A prospective cohort study was performed with a follow up of 3 years among 1334 workers from 34 companies. Work related physical load was assessed by analysing objectively measured

  6. Are neck flexion, neck rotation, and sitting at work risk factors for neck pain? : Results of a prospective cohort study

    NARCIS (Netherlands)

    Ariëns, G A; Bongers, P M; Douwes, M; Miedema, M C; Hoogendoorn, W E; van der Wal, G; Bouter, L M; van Mechelen, W

    OBJECTIVE: To study the relation between neck pain and work related neck flexion, neck rotation, and sitting. METHODS: A prospective cohort study was performed with a follow up of 3 years among 1334 workers from 34 companies. Work related physical load was assessed by analysing objectively measured

  7. The effect of ex vivo flexion and extension on intervertebral foramina dimensions in the equine cervical spine.

    Science.gov (United States)

    Sleutjens, J; Voorhout, G; Van Der Kolk, J H; Wijnberg, I D; Back, W

    2010-11-01

    In dressage, the head and neck position has become an issue of concern as certain extreme positions may imply a welfare risk for the horse. In man, extension and flexion of the cervical spine cause a decrease and increase in intervertebral foramina dimensions, respectively. However, in horses, the influence of flexion and extension on foramina dimensions and its possible interference with peripheral nerve functioning remains unknown. To determine the effect of ex vivo flexion and extension on intervertebral foramina dimensions in the equine cervical spine. Computed tomography was performed on 6 cadaver cervical spines from adult Warmblood horses subjected to euthanasia for reasons unrelated to cervical spine abnormalities, in a neutral position, in 20 and 40° extension, and in 20 and 40° flexion. Multiplanar reconstructions were made to obtain transverse images perpendicular to the long axis of each pair of intervertebral foramina from C2-T1. Intervertebral foramina dimensions were measured in the 5 positions. Compared to the neutral position, 40° extension caused a decrease in foramina dimensions at segments C4-C5, C5-C6, C6-C7 (P dimensions at segments C5-C6 (P dimensions at segments C4-T1, similar to that found in man. In vivo extension of the cervical spine could possibly interfere with peripheral nerve functioning at segments C4-T1. This effect may be even more profound in patients with a reduced intervertebral foramina space, for example in the presence of facet joint arthrosis. © 2010 EVJ Ltd.

  8. Disseminated Mycobacterium celatum infection in a white-tailed trogon (Trogon viridis)

    DEFF Research Database (Denmark)

    Bertelsen, M. F.; Grondahl, C.; Giese, Steen Bjørck

    2006-01-01

    An adult female white-tailed trogon (Trogon viridis) was presented with abdominal enlargement and hard subcutaneous masses. Necropsy findings included bony masses extending from skeletal structures, disseminated pale foci in the liver, and a pale mass in the kidney. Histological examination revea...... revealed multifocal to coalescing granulomatous inflammation in the bone, liver, kidney, lung and spleen. Mycobacterium celatum was isolated from the liver and identified by DNA sequencing. This is the first report of M. celatum infection in an avian species....

  9. Lateral movements of a massive tail influence gecko locomotion: an integrative study comparing tail restriction and autotomy.

    Science.gov (United States)

    Jagnandan, Kevin; Higham, Timothy E

    2017-09-07

    Tails are an intricate component of the locomotor system for many vertebrates. Leopard geckos (Eublepharis macularius) possess a large tail that is laterally undulated during steady locomotion. However, the tail is readily shed via autotomy, resulting in the loss of tail function, loss in body mass, and a cranial shift in the center of mass. To elucidate the function of tail undulations, we investigated changes in limb kinematics after manipulating the tail artificially by restricting tail undulations and naturally by removing the tail via autotomy. Restricting tail undulations resulted in kinematic adjustments similar to those that occur following tail autotomy, characterized by more flexed hind limb joints. These data suggest that effects of autotomy on locomotion may be linked to the loss of tail movements rather than the loss of mass or a shift in center of mass. We also provide empirical support for the link between lateral tail undulations and step length through the rotation of the pelvic girdle and retraction of the femur. Restriction and autotomy of the tail limits pelvic rotation, which reduces femur retraction and decreases step length. Our findings demonstrate a functional role for tail undulations in geckos, which likely applies to other terrestrial vertebrates.

  10. Mine Waste Technology Program Electrochemical Tailings Cover

    Science.gov (United States)

    This report summarizes the results of Mine Waste Technology Program (MWTP) Activity III, Project 40, Electrochemical Tailings Cover, funded by the U.S. Environmental Protection Agency (EPA) and jointly administered by EPA and the U.S. Department of Energy (DOE). MSE Technology A...

  11. Functional morphology of the aardvark tail.

    Science.gov (United States)

    Endo, H; Mori, K; Koyabu, D; Kawada, S; Komiya, T; Itou, T; Koie, H; Kitagawa, M; Sakai, T

    2013-04-01

    The musculoskeletal system of the aardvark (Orycteropus afer) tail was morphologically examined in two adult specimens. The tail musculature comprised three muscular groups, viz. a dorsal sacrocaudal system that consisted of the irregularly oriented Musculus sacrocaudalis dorsalis medialis and M. sacrocaudalis dorsalis lateralis, a lateral inter-vertebral connecting system, and a ventral sacrocaudal system characterized by the thick M. sacrocaudalis ventralis lateralis and M. sacrocaudalis ventralis medialis. Both the dorsal and ventral systems possessed large tendon groups that strengthened the tail structure. Computed tomography (CT) examination showed the presence of large but homogeneous cartilaginous inter-vertebral discs, whereas V-shaped bones were situated at the ventral aspect of the caudal vertebrae at the level of the inter-vertebral discs. CT visualization of the tendons and V-shaped bones in various tail positions suggested that these structures contribute to the tunnel digging action by bearing the trunk weight and lending force when the aardvark are displacing the soil by means of the forelimbs. © 2012 Blackwell Verlag GmbH.

  12. Electrokinetic remediation of copper mine tailings

    DEFF Research Database (Denmark)

    Hansen, Henrik K.; Rojo, Adrián; Ottosen, Lisbeth M.

    2007-01-01

    in sulphuric acidified tailings) without bipolar electrodes to 42% when bipolar electrodes were implemented. Furthermore, the results showed that in this system sulphuric acid addition prior to remediation was better than citric acid addition. In addition, applying a too strong electric field (even...

  13. Geotechnical parameters and behaviour of uranium tailings

    International Nuclear Information System (INIS)

    Matyas, E.L.

    1984-01-01

    The results of laboratory and in situ testing and test blasting, the observations made on a test embankment, and a description of actual construction practice associated with engineering studies for the management of uranium mill tailings at Elliot Lake, Ontario are presented. Relative density values inferred from standard penetration tests and cone penetrometer tests are shown to be inconsistent with relative density values determined from maximum and minimum void ratios. Some of the data contradicts existing correlations. The compressibility of in situ saturated tailings is presented in graphical form in terms of void ratio, vertical effective stress, and mean grain size. Hydraulic conductivity is shown to range over many orders of magnitude, depending on the void ratio. The observations on an instrumental test embankment are used to explain the appropriate selection of geotechnical parameters that gave good agreement between back-calculated and observed settlements. One-dimensional consolidation theory was found to be valid for the embankment case. It is necessary to account for changes in soil properties that occur during the consolidation process in order to obtain a good fit between back-calculated and observed settlements. The successful use of tailings sand for embankment construction is described. On the basis of normalized standard penetration resistance values, it is concluded that localized zones of saturated tailings may be prone to liquefaction under predicted earthquake loadings

  14. The tail index of exchange rate returns

    NARCIS (Netherlands)

    C.G. Koedijk (Kees); M. Schafgans (Marcia); C.G. de Vries (Casper)

    1990-01-01

    textabstractIn the literature on the empirical distribution of foreign exchange rates there is now consensus that exchange rate yields are fat-tailed. Three problems, however, persist: (1) Which class of distribution functions is most appropriate? (2) Are the parameters of the distribution invariant

  15. Uranium mill tailings and risk estimation

    International Nuclear Information System (INIS)

    Marks, S.

    1984-04-01

    Work done in estimating projected health effects for persons exposed to mill tailings at vicinity properties is described. The effect of the reassessment of exposures at Hiroshima and Nagasaki on the risk estimates for gamma radiation is discussed. A presentation of current results in the epidemiological study of Hanford workers is included. 2 references

  16. Zone-tailed Hawk (Buteo albonotatus)

    Science.gov (United States)

    Scott H. Stoleson; Giancarlo Sadoti

    2010-01-01

    The Zone-tailed Hawk (Buteo albonotatus) might well be dubbed "the Great Pretender" because it so closely resembles the ubiquitous Turkey Vulture (Cathartes aura) in appearance and behavior as to be frequently mistaken for it. In the border regions where it lives, it may be confused as well with another "Mexican" raptor, the Common Black-Hawk (...

  17. Experiments on a Tail-wheel Shimmy

    Science.gov (United States)

    Harling, R; Dietz, O

    1954-01-01

    Model tests on the "running belt" and tests with a full-scale tail wheel were made on a rotating drum as well as on a runway in order to investigate the causes of the undesirable shimmy phenomena frequently occurring on airplane tail wheels, and the means of avoiding them. The small model (scale 1:10) permitted simulation of the mass, moments of inertia, and fuselage stiffness of the airplane and determination of their influence on the shimmy, whereas by means of the larger model with pneumatic tires (scale 1:2) more accurate investigations were made on the tail wheel itself. The results of drum and road tests show good agreement with one another and with model values. Detailed investigations were made regarding the dependence of the shimmy tendency on trail, rolling speed, load, size of tires, ground friction,and inclination of the swivel axis; furthermore, regarding the influence of devices with restoring effect on the tail wheel, and the friction damping required for prevention of shimmy. Finally observations from slow-motion pictures are reported and conclusions drawn concerning the influence of tire deformation.

  18. T-tail flutter analysis using Edge

    CSIR Research Space (South Africa)

    Van Zyl, Lourens H

    2011-11-01

    Full Text Available -tail. In reality, due to some a-symmetry in the grid, this was not quite achieved. The analyses consisted of a steady solution, followed by a prescribed, sine-squared, disturbance of 0.03 radians (corresponding to 10 mm lateral displacement at the fin top...

  19. A Case of True Human Tail

    Directory of Open Access Journals (Sweden)

    Amogh R Yadav

    2013-01-01

    Full Text Available Human tail are reported from various parts of the world. Although medically innocuous, these cause anxiety & social curiosity we report a case of 09 month old child with 8 cm stalked soft tissue lesion in the sacral region. MRI spine revealed a 2 mm intraspinal lipoma in lumbar region. The appendage was excised.

  20. The Harwell TAILS computer program user's manual

    International Nuclear Information System (INIS)

    Rouse, K.D.; Cooper, M.J.

    1980-11-01

    The Harwell TAILS computer program is a versatile program for crystal structure refinement through the analysis of neutron or X-ray diffraction data from single crystals or powders. The main features of the program are described and details are given of the data input and output specifications. (author)

  1. Mechanisms of tail resorption during anuran metamorphosis.

    Science.gov (United States)

    Nakai, Yuya; Nakajima, Keisuke; Yaoita, Yoshio

    2017-09-26

    Amphibian metamorphosis has historically attracted a good deal of scientific attention owing to its dramatic nature and easy observability. However, the genetic mechanisms of amphibian metamorphosis have not been thoroughly examined using modern techniques such as gene cloning, DNA sequencing, polymerase chain reaction or genomic editing. Here, we review the current state of knowledge regarding molecular mechanisms underlying tadpole tail resorption.

  2. Posterior cruciate ligament recruitment affects antero-posterior translation during flexion gap distraction in total knee replacement. An intraoperative study involving 50 patients.

    NARCIS (Netherlands)

    Heesterbeek, P.J.C.; Keijsers, N.; Jacobs, W.; Verdonschot, N.J.J.; Wymenga, A.B.

    2010-01-01

    BACKGROUND AND PURPOSE: Because of the oblique orientation of the posterior cruciate ligament (PCL), flexion gap distraction could lead to anterior movement of the tibia, which would influence the tibiofemoral contact point. This would affect the kinematics of the TKR. We assessed the flexion gap

  3. Serial casting versus stretching technique to treat knee flexion contracture in children with spina bifida: a comparative study.

    Science.gov (United States)

    Al-Oraibi, S; Tariah, Hashem Abu; Alanazi, Abdullah

    2013-01-01

    Severe knee contractures that develop soon after muscle imbalance may not improve with stretching exercises and splinting. An alternative treatment is serial casting, which has been used to promote increased range of motion. The purpose of this study was to compare the effectiveness of using serial casting and passive stretching approaches to treat knee flexion contracture in children with spina bifida. In a pre/post randomized controlled study, ten participants were included in the serial casting group, while eight participants were included in the passive stretching intervention group. The degree of knee extension was measured at baseline, immediately after intervention, and at a one-year follow-up using a standard goniometer. Both groups showed significant improvements in the degree of flexion contracture at the post-treatment evaluation and the follow-up evaluation. The serial casting group showed significant improvements in knee flexion contracture at the post-treatment evaluation, t (9)=13.4, p casting group compared with passive stretching group in relation to the degree of flexion contracture were found at the immediate post-treatment evaluation, F(1, 15)=246, p=0.0001, and the one-year follow-up evaluation, F (1, 15)=51.5, p=0.0001. The outcomes of this study provide the first evidence that serial casting may be a useful intervention in treating knee flexion contracture in children with spina bifida. However, further investigations into serial casting, as well as investigations into the use of serial casting with other interventions, are warranted.

  4. On the Hydrodynamics of Anomalocaris Tail Fins.

    Science.gov (United States)

    Sheppard, K A; Rival, D E; Caron, J-B

    2018-04-25

    Anomalocaris canadensis, a soft-bodied stem-group arthropod from the Burgess Shale, is considered the largest predator of the Cambrian period. Thanks to a series of lateral flexible lobes along its dorso-ventrally compressed body, it is generally regarded as an efficient swimmer, well-adapted to its predatory lifestyle. Previous theoretical hydrodynamic simulations have suggested a possible optimum in swimming performance when the lateral lobes performed as a single undulatory lateral fin, comparable to the pectoral fins in skates and rays. However, the role of the unusual fan-like tail of Anomalocaris has not been previously explored. Swimming efficiency and maneuverability deduced from direct hydrodynamic analysis are here studied in a towing tank facility using a three-vane physical model designed as an abstraction of the tail fin. Through direct force measurements, it was found that the model exhibited a region of steady-state lift and drag enhancement at angles of attack greater than 25° when compared to a triangular-shaped reference model. This would suggest that the resultant normal force on the tail fin of Anomalocaris made it well-suited for turning maneuvers, giving it the ability to turn quickly and through small radii of curvature. These results are consistent with an active predatory lifestyle, although detailed kinematic studies integrating the full organism, including the lateral lobes, would be required to test the effect of the tail fin on overall swimming performance. This study also highlights a possible example of evolutionary convergence between the tails of Anomalocaris and birds, which, in both cases, are well-adapted to efficient turning maneuvers.

  5. Histone H2A mobility is regulated by its tails and acetylation of core histone tails

    International Nuclear Information System (INIS)

    Higashi, Tsunehito; Matsunaga, Sachihiro; Isobe, Keisuke; Morimoto, Akihiro; Shimada, Tomoko; Kataoka, Shogo; Watanabe, Wataru; Uchiyama, Susumu; Itoh, Kazuyoshi; Fukui, Kiichi

    2007-01-01

    Histone tail domains play important roles in cellular processes, such as replication, transcription, and chromosome condensation. Histone H2A has one central and two tail domains, and their functions have mainly been studied from a biochemical perspective. In addition, analyses based on visualization have been employed for functional analysis of some chromatin proteins. In this study, we analyzed histone H2A mobility in vivo by two-photon FRAP, and elucidated that the histone H2A N- and C-terminal tails regulate its mobility. We found that histone H2A mobility was increased following treatment of host cells with a histone deacetylase inhibitor. Our results support a model in which core histone tails directly regulate transcription by interacting with nucleosome DNA via electrostatic interactions

  6. Quengel Casting for the Management of Pediatric Knee Flexion Contractures: A 26-Year Single Institution Experience.

    Science.gov (United States)

    Wiley, Marcel R; Riccio, Anthony I; Felton, Kevin; Rodgers, Jennifer A; Wimberly, Robert L; Johnston, Charles E

    Quengel casting was introduced in 1922 for nonsurgical treatment of knee flexion contractures (KFC) associated with hemophilic arthropathy. It consists of an extension-desubluxation hinge fixed to a cast allowing for gradual correction of a flexion deformity while preventing posterior tibial subluxation. The purpose of this study is to report 1 center's experience with this technique for the treatment of pediatric KFC. A retrospective review was conducted over a 26-year period. All patients with KFC treated with Quengel casting were included. Demographic data, associated medical conditions, adjunctive soft tissue releases, complications, and the need for late surgical intervention were recorded. Tibiofemoral angle measurements in maximal extension were recorded at initiation and termination of casting, 1-year follow-up, and final follow-up. Success was defined as no symptomatic recurrence of KFC or need for subsequent surgery. Eighteen patients (26 knees) were treated for KFC with Quengel casting. Average age at initiation of casting was 8.1 years with average follow-up of 59.9 months. Fifteen knees (58%) underwent soft tissue releases before casting. An average of 1.5 casts per knee were applied over an average of 23.9 days. Average KFC before casting was 50.6 degrees (range, 15 to 100 degrees) which improved to 5.96 degrees (0 to 40 degrees) at cast removal (Pcasting before 1 year. Of these, 11 knees (50%) had a successful outcome. Residual KFC of those treated successfully was 6.8 degrees (range, 0 to 30 degrees) at 1 year and 8.2 degrees (range, 0 to 30 degrees) at final follow-up, averaging 71.4 months (P=0.81). Of the 11 knees deemed failures, all had recurrence of deformity within an average of 1 year from cast removal. Surgical release before Quengel casting did not improve the chances for success (P=0.09). Quengel casting can improve pediatric KFC an average of 44.2 degrees with minimal complications. Although 50% of treated patients will demonstrate

  7. Limb flexion-induced axial compression and bending in human femoropopliteal artery segments.

    Science.gov (United States)

    Poulson, William; Kamenskiy, Alexey; Seas, Andreas; Deegan, Paul; Lomneth, Carol; MacTaggart, Jason

    2018-02-01

    High failure rates of femoropopliteal artery (FPA) interventions are often attributed in part to severe mechanical deformations that occur with limb movement. Axial compression and bending of the FPA likely play significant roles in FPA disease development and reconstruction failure, but these deformations are poorly characterized. The goal of this study was to quantify axial compression and bending of human FPAs that are placed in positions commonly assumed during the normal course of daily activities. Retrievable nitinol markers were deployed using a custom-made catheter system into 28 in situ FPAs of 14 human cadavers. Contrast-enhanced, thin-section computed tomography images were acquired with each limb in the standing (180 degrees), walking (110 degrees), sitting (90 degrees), and gardening (60 degrees) postures. Image segmentation and analysis allowed relative comparison of spatial locations of each intra-arterial marker to determine axial compression and bending using the arterial centerlines. Axial compression in the popliteal artery (PA) was greater than in the proximal superficial femoral artery (SFA) or the adductor hiatus (AH) segments in all postures (P = .02). Average compression in the SFA, AH, and PA ranged from 9% to 15%, 11% to 19%, and 13% to 25%, respectively. The FPA experienced significantly more acute bending in the AH and PA segments compared with the proximal SFA (P < .05) in all postures. In the walking, sitting, and gardening postures, average sphere radii in the SFA, AH, and PA ranged from 21 to 27 mm, 10 to 18 mm, and 8 to 19 mm, whereas bending angles ranged from 150 to 157 degrees, 136 to 147 degrees, and 137 to 148 degrees, respectively. The FPA experiences significant axial compression and bending during limb flexion that occur at even modest limb angles. Moreover, different segments of the FPA appear to undergo significantly different degrees of deformation. Understanding the effects of limb flexion on axial compression and

  8. Tail-robust scheduling using Limited Processor Sharing.

    NARCIS (Netherlands)

    Nair, J.K.; Wierman, A.; Zwart, A.P.

    2010-01-01

    From a rare events perspective, scheduling disciplines that work well under light (exponential) tailed workload distributions do not perform well under heavy (power) tailed workload distributions, and vice versa, leading to fundamental problems in designing schedulers that are robust to

  9. ESTIMATION OF FILTRATION CAPACITY OF POSTFLOTATION TAILINGS EMBEDDED IN DAMS OF TAILINGS DEPOSITION SITES

    Directory of Open Access Journals (Sweden)

    Wojciech Tschuschke

    2015-10-01

    Full Text Available Construction of very big mine tailings deposition sites, such as postflotation tailings ponds, is a complicated engineering task, in which several technical and environmental problems need to be solved. Designing, construction and operation of such an object applying the monitoring method consists in the verification of design assumptions based on continuous observations. One of the primary tasks of monitoring while the deposition site is being filled with tailings is to control quality of the formed dam embankments, as the structural element of the object responsible for its stability. In order to use material selected from deposited tailings in the construction of dams it is necessary to define grain size and compaction criteria, which directly affect load bearing capacity and deformation of the structure. For this reason main control tests include the analyses of grain size distribution and physical properties of the material embedded in the dams. These data may also be used to estimate filtration capacity of the embankment. A lack of drainage, causing accumulation of water within the embankment, may potentially deteriorate stability conditions. This paper presents the use of empirical formulas, i.e. formulas typically applied to natural soils, to assess permeability coefficient of tailings. A simple empirical formula was also proposed for the estimation of permeability coefficient of tailings based on grain size and compaction parameters determined in routine quality tests of constructed dam embankments.

  10. Tail-assisted pitch control in lizards, robots and dinosaurs.

    Science.gov (United States)

    Libby, Thomas; Moore, Talia Y; Chang-Siu, Evan; Li, Deborah; Cohen, Daniel J; Jusufi, Ardian; Full, Robert J

    2012-01-04

    In 1969, a palaeontologist proposed that theropod dinosaurs used their tails as dynamic stabilizers during rapid or irregular movements, contributing to their depiction as active and agile predators. Since then the inertia of swinging appendages has been implicated in stabilizing human walking, aiding acrobatic manoeuvres by primates and rodents, and enabling cats to balance on branches. Recent studies on geckos suggest that active tail stabilization occurs during climbing, righting and gliding. By contrast, studies on the effect of lizard tail loss show evidence of a decrease, an increase or no change in performance. Application of a control-theoretic framework could advance our general understanding of inertial appendage use in locomotion. Here we report that lizards control the swing of their tails in a measured manner to redirect angular momentum from their bodies to their tails, stabilizing body attitude in the sagittal plane. We video-recorded Red-Headed Agama lizards (Agama agama) leaping towards a vertical surface by first vaulting onto an obstacle with variable traction to induce a range of perturbations in body angular momentum. To examine a known controlled tail response, we built a lizard-sized robot with an active tail that used sensory feedback to stabilize pitch as it drove off a ramp. Our dynamics model revealed that a body swinging its tail experienced less rotation than a body with a rigid tail, a passively compliant tail or no tail. To compare a range of tails, we calculated tail effectiveness as the amount of tailless body rotation a tail could stabilize. A model Velociraptor mongoliensis supported the initial tail stabilization hypothesis, showing as it did a greater tail effectiveness than the Agama lizards. Leaping lizards show that inertial control of body attitude can advance our understanding of appendage evolution and provide biological inspiration for the next generation of manoeuvrable search-and-rescue robots.

  11. Engineering assessment of inactive uranium mill tailings, Durango site, Durango, Colorado. A summary of the Phase II, Title I

    International Nuclear Information System (INIS)

    1977-11-01

    Ford, Bacon and Davis Utah Inc. has performed an engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at Durango, Colorado. The Phase II, Title I services include the preparation of topographic maps, the performance of core drillings and radiometric measurements sufficient to determine areas and volumes of tailings and other radium-contaminated materials, the evaluation of resulting radiation exposures of individuals and nearby populations, the investigation of site hydrology and meteorology and the evaluation and costing of alternative corrective actions. Radon gas release from the 1.555 million tons of tailings at the Durango site constitutes the most significant environmental impact, although windblown tailings and external gamma radiation are also factors. The eight alternative actions presented range from vegetative stabilization (Option I), to contouring and stabilizing in-place with varying depths of cover material (Options II and III), to removal to an isolated long-term disposal site (Options V to VIII). All options include remedial action costs for offsite locations where tailings have been placed. Costs estimated for the eight options range from $4,340,000 to $13,590,000. Reprocessing the tailings for uranium is sufficiently economically attractive to justify reprocessing in conjunction with each of the options

  12. Analysis of right anterolateral impacts: the effect of trunk flexion on the cervical muscle whiplash response

    Directory of Open Access Journals (Sweden)

    Narayan Yogesh

    2006-05-01

    Full Text Available Abstract Background The cervical muscles are considered a potential site of whiplash injury, and there is a need to understand the cervical muscle response under non-conventional whiplash impact scenarios, including variable body position and impact direction. There is no data, however, on the effect of occupant position on the muscle response to frontal impacts. Therefore, the objective of the study was to measure cervical muscle response to graded right anterolateral impacts. Methods Twenty volunteers were subjected to right anterolateral impacts of 4.3, 7.8, 10.6, and 12.8 m/s2 acceleration with their trunk flexed forward 45 degrees and laterally flexed right or left by 45 degrees. Bilateral EMG of the sternocleidomastoids, trapezii, and splenii capitis and acceleration of the sled, torso, and head were measured. Results and discussion With either direction of trunk flexion at impact, the trapezius EMGs increased with increasing acceleration (p Conclusion When the subject sits with trunk flexed out of neutral posture at the time of anterolateral impact, the cervical muscle response is dramatically reduced compared to frontal impacts with the trunk in neutral posture. In the absence of bodily impact, the flexed trunk posture appears to produce a biomechanical response that would decrease the likelihood of cervical muscle injury in low velocity impacts.

  13. Serial elongation derotation flexion (EDF) casting for patients with infantile and juvenile scoliosis.

    Science.gov (United States)

    Canavese, Federico; Rousset, Marie; Mansour, Mounira; Samba, Antoine; Dimeglio, Alain

    2016-02-01

    Infantile and juvenile scoliosis, among different types of spinal deformity, is still a challenge for pediatric orthopedic surgeons. The ideal treatment of infantile and juvenile scoliosis has not yet been identified as both clinicians and surgeons still face multiple challenges, including preservation of the thoracic spine, thoracic cage, lung growth and cardiac function without reducing spinal motion. Elongation, derotation, flexion (EDF) casting technique is a custom-made thoracolumbar cast based on a three dimensional correction concept. This cast offers three-dimensional correction and can control the evolution of the deformity in some cases. Spinal growth can be guided by EDF casting as it can influence the initially curved spine to grow straighter. This article aimed to provide a comprehensive review of how infantile and juvenile scoliosis can affect normal spine and thorax and how these deformities can be treated with serial EDF casting technique. A current literature review is mandatory in order to understand the principles of the serial EDF casting technique and the effectiveness of conservative treatment in young and very young patients.

  14. Serial elongation-derotation-flexion casting for children with early-onset scoliosis.

    Science.gov (United States)

    Canavese, Federico; Samba, Antoine; Dimeglio, Alain; Mansour, Mounira; Rousset, Marie

    2015-12-18

    Various early-onset spinal deformities, particularly infantile and juvenile scoliosis (JS), still pose challenges to pediatric orthopedic surgeons. The ideal treatment of these deformities has yet to emerge, as both clinicians and surgeons still face multiple challenges including preservation of thoracic motion, spine and cage, and protection of cardiac and lung growth and function. Elongation-derotation-flexion (EDF) casting is a technique that uses a custom-made thoracolumbar cast based on a three-dimensional correction concept. EDF can control progression of the deformity and - in some cases-coax the initially-curved spine to grow straighter by acting simultaneously in the frontal, sagittal and coronal planes. Here we provide a comprehensive review of how infantile and JS can affect normal spine and thorax and how serial EDF casting can be used to manage these spinal deformities. A fresh review of the literature helps fully understand the principles of the serial EDF casting technique and the effectiveness of conservative treatment in patients with early-onset spinal deformities, particularly infantile and juvenile scolisois.

  15. Immediate effects of the toe spreader on the tonic toe flexion reflex.

    Science.gov (United States)

    de Saca, L R; Catlin, P A; Segal, R L

    1994-06-01

    The purpose of the study was to determine whether the use of a toe spreader to inhibit the tonic toe flexion reflex (TTFR) immediately alters temporal-distance gait characteristics, plantar surface contact, or muscle activity in the limb exhibiting the TTFR of subjects with hemiparesis secondary to supraspinal lesion. Eighteen adults with hemiparesis secondary to supraspinal lesions served as subjects for the standing portion of the study. Sixteen of the subjects participated in the gait portion of the study. The study was a randomized, within-subject, between-conditions comparison consisting of standing and gait phases, with four conditions for each phase (shoe off, toe spreader off/on, shoe on, toe spreader off/on). Measures performed were ink footprint gait analysis and integrated electromyography from the limb exhibiting the TTFR. Presence of the TTFR was reduced significantly with the use of the toe spreader. Velocity and cadence were increased significantly by use of the toe spreader. The toe spreader may be a useful treatment option for improving gait. The clinical significance of these findings, however, will depend on the functional context of toe-spreader use.

  16. 3D Analysis of the Proximal Interphalangeal Joint Kinematics during Flexion

    Directory of Open Access Journals (Sweden)

    Florian Hess

    2013-01-01

    Full Text Available Background. Dynamic joint motion recording combined with CT-based 3D bone and joint surface data is accepted as a helpful and precise tool to analyse joint. The purpose of this study is to demonstrate the feasibility of these techniques for quantitative motion analysis of the interphalangeal joint in 3D. Materials and Method. High resolution motion data was combined with an accurate 3D model of a cadaveric index finger. Three light-emitting diodes (LEDs were used to record dynamic data, and a CT scan of the finger was done for 3D joint surface geometry. The data allowed performing quantitative evaluations such as finite helical axis (FHA analysis, coordinate system optimization, and measurement of the joint distances in 3D. Results. The FHA varies by 4.9±1.7° on average. On average, the rotation in adduction/abduction and internal/external rotation were 0.3±0.91° and 0.1±0.97°, respectively. During flexion, a translational motion between 0.06 mm and 0.73 mm was observed. Conclusions. The proposed technique and methods appear to be feasible for the accurate assessment and evaluation of the PIP joint motion in 3D. The presented method may help to gain additional insights for the design of prosthetic implants, rehabilitation, and new orthotic devices.

  17. Trunk muscle activation. The effects of torso flexion, moment direction, and moment magnitude.

    Science.gov (United States)

    Lavender, S; Trafimow, J; Andersson, G B; Mayer, R S; Chen, I H

    1994-04-01

    This study was performed to quantify the electromyographic trunk muscle activities in response to variations in moment magnitude and direction while in forward-flexed postures. Recordings were made over eight trunk muscles in 19 subjects who maintained forward-flexed postures of 30 degrees and 60 degrees. In each of the two flexed postures, external moments of 20 Nm and 40 Nm were applied via a chest harness. The moment directions were varied in seven 30 degrees increments to a subject's right side, such that the direction of the applied load ranged from the upper body's anterior midsagittal plane (0 degree) to the posterior midsagittal plane (180 degrees). Statistical analyses yielded significant moment magnitude by moment-direction interaction effects for the EMG output from six of the eight muscles. Trunk flexion by moment-direction interactions were observed in the responses from three muscles. In general, the primary muscle supporting the torso and the applied load was the contralateral (left) erector spinae. The level of electromyographic activity in the anterior muscles was quite low, even with the posterior moment directions.

  18. Motion as motivation: using repetitive flexion movements to stimulate the approach system.

    Science.gov (United States)

    Haeffel, Gerald J

    2011-12-01

    Research suggests that having a healthy approach system is critical for adaptive emotional functioning. The goal of the current study (n=186 undergraduates) was to determine the efficacy of an easy-to-disseminate and cost-efficient strategy for stimulating this system. The experiment tested the effects of repeated flexion movements (rFM) on approach system activation as measured by both self-report (BAS scales) and behavior. The results showed that rFM increased approach system motivation in men but not women. Men who completed the rFM task reported significantly greater levels of fun-seeking motivation than men in the control task. Moreover, the rFM task led to changes in actual behavior. Men who completed the rFM task exhibited significantly greater persistence on a difficult laboratory task than men in the control task. In contrast, women who completed the rFM task reported significantly lower levels of fun seeking and tended to exhibit less persistence on a difficult laboratory task than women in the control task. These results provide support for embodied theories of emotion as well as additional evidence for a gender difference in approach-avoidance tendencies. Copyright © 2011. Published by Elsevier Ltd.

  19. Systematic review of flexion/extension radiography of the cervical spine in trauma patients

    International Nuclear Information System (INIS)

    Sierink, J.C.; Lieshout, W.A.M. van; Beenen, L.F.M.; Schep, N.W.L.; Vandertop, W.P.; Goslings, J.C.

    2013-01-01

    Introduction: The aim of this review was to investigate whether Flexion/Extension (F/E) radiography adds diagnostic value to CT or MRI in the detection of cervical spine ligamentous injury and/or clinically significant cervical spine instability of blunt trauma patients. Methods: A systematic search of literature was done in Pubmed, Embase and Cochrane Library databases. Primary outcome was sensitivity and specificity of F/E radiography. Secondary outcomes were the positive predicting value (PPV) and negative predicting value (NPV) (with CT or MRI as reference tests due to the heterogeneity of the included studies) of each modality and the quality of F/E radiography. Results: F/E radiography was overall regarded to be inferior to CT or MRI in the detection of ligamentous injury. This was reflected by the high specificity and NPV for CT with F/E as reference test (ranging from 97 to 100% and 99 to 100% respectively) and the ambiguous results for F/E radiography with MRI as its reference test (0–98% and 0–83% for specificity and NPV respectively). Image quality of F/E radiography was reported to have 31 to 70% adequacy, except in two studies which reported an adequacy of respectively 4 and 97%. Conclusion: This systematic review of the literature shows that F/E radiography adds little diagnostic value to the evaluation of blunt trauma patients compared to CT and MRI, especially in those cases where CT or MRI show no indication of ligamentous injury

  20. Systematic review of flexion/extension radiography of the cervical spine in trauma patients

    Energy Technology Data Exchange (ETDEWEB)

    Sierink, J.C., E-mail: j.c.sierink@amc.nl [Trauma Unit, Department of Surgery, Academic Medical Center, Meibergdreef 9, 1105 AZ Amsterdam (Netherlands); Lieshout, W.A.M. van, E-mail: w.a.vanlieshout@amc.nl [Trauma Unit, Department of Surgery, Academic Medical Center, Meibergdreef 9, 1105 AZ Amsterdam (Netherlands); Beenen, L.F.M., E-mail: l.f.beenen@amc.nl [Department of Radiology, Academic Medical Center, Meibergdreef 9, 1105 AZ Amsterdam (Netherlands); Schep, N.W.L., E-mail: n.w.schep@amc.nl [Trauma Unit, Department of Surgery, Academic Medical Center, Meibergdreef 9, 1105 AZ Amsterdam (Netherlands); Vandertop, W.P., E-mail: w.p.vandertop@amc.nl [Neurosurgical Center Amsterdam, Academic Medical Center, Meibergdreef 9, 1105 AZ Amsterdam (Netherlands); Goslings, J.C., E-mail: j.c.goslings@amc.nl [Trauma Unit, Department of Surgery, Academic Medical Center, Meibergdreef 9, 1105 AZ Amsterdam (Netherlands)

    2013-06-15

    Introduction: The aim of this review was to investigate whether Flexion/Extension (F/E) radiography adds diagnostic value to CT or MRI in the detection of cervical spine ligamentous injury and/or clinically significant cervical spine instability of blunt trauma patients. Methods: A systematic search of literature was done in Pubmed, Embase and Cochrane Library databases. Primary outcome was sensitivity and specificity of F/E radiography. Secondary outcomes were the positive predicting value (PPV) and negative predicting value (NPV) (with CT or MRI as reference tests due to the heterogeneity of the included studies) of each modality and the quality of F/E radiography. Results: F/E radiography was overall regarded to be inferior to CT or MRI in the detection of ligamentous injury. This was reflected by the high specificity and NPV for CT with F/E as reference test (ranging from 97 to 100% and 99 to 100% respectively) and the ambiguous results for F/E radiography with MRI as its reference test (0–98% and 0–83% for specificity and NPV respectively). Image quality of F/E radiography was reported to have 31 to 70% adequacy, except in two studies which reported an adequacy of respectively 4 and 97%. Conclusion: This systematic review of the literature shows that F/E radiography adds little diagnostic value to the evaluation of blunt trauma patients compared to CT and MRI, especially in those cases where CT or MRI show no indication of ligamentous injury.

  1. Reliable four-point flexion test and model for die-to-wafer direct bonding

    Energy Technology Data Exchange (ETDEWEB)

    Tabata, T., E-mail: toshiyuki.tabata@cea.fr; Sanchez, L.; Fournel, F.; Moriceau, H. [Univ. Grenoble Alpes, F-38000 Grenoble, France and CEA, LETI, MINATEC Campus, F-38054 Grenoble (France)

    2015-07-07

    For many years, wafer-to-wafer (W2W) direct bonding has been very developed particularly in terms of bonding energy measurement and bonding mechanism comprehension. Nowadays, die-to-wafer (D2W) direct bonding has gained significant attention, for instance, in photonics and microelectro-mechanics, which supposes controlled and reliable fabrication processes. So, whatever the stuck materials may be, it is not obvious whether bonded D2W structures have the same bonding strength as bonded W2W ones, because of possible edge effects of dies. For that reason, it has been strongly required to develop a bonding energy measurement technique which is suitable for D2W structures. In this paper, both D2W- and W2W-type standard SiO{sub 2}-to-SiO{sub 2} direct bonding samples are fabricated from the same full-wafer bonding. Modifications of the four-point flexion test (4PT) technique and applications for measuring D2W direct bonding energies are reported. Thus, the comparison between the modified 4PT and the double-cantilever beam techniques is drawn, also considering possible impacts of the conditions of measures such as the water stress corrosion at the debonding interface and the friction error at the loading contact points. Finally, reliability of a modified technique and a new model established for measuring D2W direct bonding energies is demonstrated.

  2. Prototype of a mechanical assistance device for the wrists' flexion-extension movement

    International Nuclear Information System (INIS)

    Politti, Julio C; Puglisi, Lisandro J; Farfan, Fernando D

    2007-01-01

    Using CMU actuators, a Prototype of Mechanical Assistance Device for the Wrist's Flexion Movement (PMA) was developed and probed in a mechanical model, in order to be implemented in a future as a dynamic powered orthosis or as a rehabilitation assistant instrument. Two Mayor Actuators conformed by three CMU actuators arranged in a series configuration, allows to an artificial hand to be placed in four predefined positions: 0 0 , 20 0 , 40 0 and 60 0 . The synchronism and control of the actuators is achieved with the Programmable Control Module (PCM). It is capable to drive up to six CMU actuators, and possess two different modes of execution: a Manual mode and an Exercise mode. In the Manual Mode, the position of the hand responds directly to the commands of the keyboard of the front panel, and in the Exercise mode, the hand realizes a repetitive and programmed movement. The prototype was tested in 100 positions in the Manual Mode and for 225 works cycles in the Exercise Mode. The relative repetition error was less than 5% for both test. This prototype only consumes 4,15W, which makes it possible to be powered by small rechargeable batteries, allowing its use as a portable device

  3. MR imaging evaluation of the temporomandibular joint following cervical extension-flexion injury (whiplash)

    International Nuclear Information System (INIS)

    Shellock, F.G.; Pressman, B.D.; Schames, J.; Schames, M.; Meeks, T.

    1990-01-01

    To determine abnormalities of the temporomandibular joint (TMJ) associated with cervical extension-flexion injury (whiplash) with use of MR imaging. Sixteen patients (32 joints) with TMJ syndrome-related symptoms after whiplash injuries from automobile accidents were evaluated by MR imaging. None of the patients had direct trauma to the jaw, mouth, or face. T1-weighted closed- and opened-mouth views were obtained in the sagittal plane, and closed-mouth views were obtained in the coronal plane. T2-weighted closed-mouth views obtained in the sagittal plane were also obtained to optimize identification of fluid/edema. Fourteen (87%) of 16 patients had one or more of the following TMJ abnormalities: 11 (34%) had anterior displacement of the disk with reduction and 2 (6%) had anterior displacement of the disk without reduction. On T2-weighted images, 17 TMJs (53%) had joint fluid and 5 (16%) had fluid localized to the capsule and/or pterygoid muscle. These data demonstrated a high incidence of TMJ abnormalities related to whiplash injury. The predominant finding was associated fluid/edema, suggesting that T2-weighted images are particularly useful for the evaluation of patients who present with whiplash injury

  4. Peak activation of lower limb musculature during high flexion kneeling and transitional movements.

    Science.gov (United States)

    Kingston, David C; Tennant, Liana M; Chong, Helen C; Acker, Stacey M

    2016-09-01

    Few studies have measured lower limb muscle activation during high knee flexion or investigated the effects of occupational safety footwear. Therefore, our understanding of injury and disease mechanisms, such as knee osteoarthritis, is limited for these high-risk postures. Peak activation was assessed in eight bilateral lower limb muscles for twelve male participants, while shod or barefoot. Transitions between standing and kneeling had peak quadriceps and tibialis anterior (TA) activations above 50% MVC. Static kneeling and simulated tasks performed when kneeling had peak TA activity above 15% MVC but below 10% MVC for remaining muscles. In three cases, peak muscle activity was significantly higher (mean 8.9% MVC) when shod. However, net compressive knee joint forces may not be significantly increased when shod. EMG should be used as a modelling input when estimating joint contact forces for these postures, considering the activation levels in the hamstrings and quadriceps muscles during transitions. Practitioner Summary: Kneeling transitional movements are used in activities of daily living and work but are linked to increased knee osteoarthritis risk. We found peak EMG activity of some lower limb muscles to be over 70% MVC during transitions and minimal influence of wearing safety footwear.

  5. A new procedure for deep sea mining tailings disposal

    NARCIS (Netherlands)

    Ma, W.; Schott, D.L.; Lodewijks, G.

    2017-01-01

    Deep sea mining tailings disposal is a new environmental challenge related to water pollution, mineral crust waste handling, and ocean biology. The objective of this paper is to propose a new tailings disposal procedure for the deep sea mining industry. Through comparisons of the tailings disposal

  6. Costs associated with tail autotomy in an ambush foraging lizard ...

    African Journals Online (AJOL)

    We induced tail autotomy in free ranging male Cordylus m. melanotus and measured potential shifts in behaviour (movements, foraging behaviour, time exposed and average distance to a potential refuge), and responses to an approaching human compared to marked individuals with complete tails. Tailed and tailless ...

  7. Spectrum of human tails: A report of six cases

    Directory of Open Access Journals (Sweden)

    Biswanath Mukhopadhyay

    2012-01-01

    Full Text Available Human tail is a curiosity, a cosmetic stigma and presents as an appendage in the lumbosacral region. Six patients of tail in the lumbosacral region are presented here to discuss the spectrum of presentation of human tails. The embryology, pathology and treatment of this entity are discussed along with a brief review of the literature.

  8. Uranium Mill Tailings Remedial Action Project surface project management plan

    International Nuclear Information System (INIS)

    1994-09-01

    This Project Management Plan describes the planning, systems, and organization that shall be used to manage the Uranium Mill Tailings Remedial Action Project (UMTRA). US DOE is authorized to stabilize and control surface tailings and ground water contamination at 24 inactive uranium processing sites and associated vicinity properties containing uranium mill tailings and related residual radioactive materials

  9. Leachability of metals from gold tailings by rainwater: an ...

    African Journals Online (AJOL)

    Mine leachates from gold tailings impoundments usually contain elevated concentrations of metals and sulphates that impact negatively on water quality. This study was aimed at assessing the leachability of such metals from tailings by rainwater. Oxidised and unoxidised tailings were leached experimentally and through ...

  10. How We Tend To Overestimate Powerlaw Tail Exponents

    OpenAIRE

    Nassim N. Taleb

    2012-01-01

    In the presence of a layer of metaprobabilities (from uncertainty concerning the parameters), the asymptotic tail exponent corresponds to the lowest possible tail exponent regardless of its probability. The problem explains "Black Swan" effects, i.e., why measurements tend to chronically underestimate tail contributions, rather than merely deliver imprecise but unbiased estimates.

  11. Endocrine carcinoma of the pancreatic tail exhibiting gastric variceal bleeding

    Directory of Open Access Journals (Sweden)

    Si-Yuan Wu

    2014-01-01

    Full Text Available Nonfunctional endocrine carcinoma of the pancreas is uncommon. Without excess hormone secretion, it is clinically silent until the enlarging or metastatic tumor causes compressive symptoms. Epigastric pain, dyspepsia, jaundice, and abdominal mass are the usual symptoms, whereas upper gastrointestinal (GI bleeding is rare. Here, we describe the case of a 24-year-old man with the chief complaint of hematemesis. Upper GI panendoscopy revealed isolated gastric varices at the fundus and upper body. Ultrasonography and computed tomography showed a tumor mass at the pancreatic tail causing a splenic vein obstruction, engorged vessels near the fundus of the stomach, and splenomegaly. After distal pancreatectomy and splenectomy, the bleeding did not recur. The final pathologic diagnosis was endocrine carcinoma of the pancreas. Gastric variceal bleeding is a possible manifestation of nonfunctional endocrine carcinoma of the pancreas if the splenic vein is affected by a tumor. In non-cirrhotic patients with isolated gastric variceal bleeding, the differential diagnosis should include pancreatic disorders.

  12. Evaluation of microbial biofilm communities from an Alberta oil sands tailings pond.

    Science.gov (United States)

    Golby, Susanne; Ceri, Howard; Gieg, Lisa M; Chatterjee, Indranil; Marques, Lyriam L R; Turner, Raymond J

    2012-01-01

    Bitumen extraction from the oil sands of Alberta has resulted in millions of cubic meters of waste stored on-site in tailings ponds. Unique microbial ecology is expected in these ponds, which may be key to their bioremediation potential. We considered that direct culturing of microbes from a tailings sample as biofilms could lead to the recovery of microbial communities that provide good representation of the ecology of the tailings. Culturing of mixed species biofilms in vitro using the Calgary Biofilm Device (CBD) under aerobic, microaerobic, and anaerobic growth conditions was successful both with and without the addition of various growth nutrients. Denaturant gradient gel electrophoresis and 16S rRNA gene pyrotag sequencing revealed that unique mixed biofilm communities were recovered under each incubation condition, with the dominant species belonging to Pseudomonas, Thauera, Hydrogenophaga, Rhodoferax, and Acidovorax. This work used an approach that allowed organisms to grow as a biofilm directly from a sample collected of their environment, and the biofilms cultivated in vitro were representative of the endogenous environmental community. For the first time, representative environmental mixed species biofilms have been isolated and grown under laboratory conditions from an oil sands tailings pond environment and a description of their composition is provided.

  13. Studies of red soils as capping the uranium mill tailing impoundments

    International Nuclear Information System (INIS)

    Wen Zhijian; Chen Zhangru; Liu Zhengyi; Chen Guoliang

    2001-01-01

    Capping is one of the important technical engineering measures to assure the long term stabilization and isolation of uranium mill tailings. This paper reports in situ surveys of radon emanations before and after tailings slurries were capped with local red soils at the uranium mill tailings. The data obtained by soil-gas surveys reveal that radon emanation decreased with an increase in capping thickness. The dry density of the capping materials also plays an important role in preventing radon emanation. The measurement results show that utilizing high densities of red soils as capping materials can significantly decrease the required thickness of the capping. The analytical results from borehole red soil samples show that uranium, thorium, and radium contents are consistent with the regional environmental radioactivity level. The studies of the mineralogical composition indicate that the local red soils are rich in clay minerals, e.g. kaolinite, illite and mica vermiculite mixed-layer minerals, which would play an active role in preventing radionuclide release to the surrounding environment. A conceptual model for remediation of south China's uranium mill tailing has been developed

  14. Sub-stratum injection of fine tailings

    Energy Technology Data Exchange (ETDEWEB)

    Kesteren van, W.; Cornelisse, J.; Costello, M. [Deltares, Delft (Netherlands)

    2010-07-01

    This PowerPoint presentation discussed an experiment conducted to evaluate the sub-stratum injection of oil sands fine tailings. The hydraulic fracturing method was developed as a sub-surface dredging process for mining sand without removing the overburden. Pressure was used to transport the sand-water mixture, and the high pressures used in the process resulted in water losses through the clay-sand interface. The experiment was conducted with soft clay, compacted sand, and an injection feed. Results of the study showed that the injection method may be successful. However, further research is required to characterize the fracture energy of oil sands and the rheology of fine tailings. Horizontal hydraulic fracturing equations were presented. Tensile failures in clay and oil sands were discussed. Fractures were identified by deformation and discharge rates. Crack propagation methods were also studied. tabs., figs.

  15. Factors influencing radon attenuation by tailing covers

    International Nuclear Information System (INIS)

    Silker, W.B.; Rogers, V.C.

    1981-07-01

    The US NRC, in its Generic Environmental Impact Statement on uranium milling has specified that the radon flux escaping a uranium mill tailings pile will be reduced to pCi/m 2 s by application of covering layers of soils and clays. These covers present a radon diffusion barrier, which sufficiently increases the time required for radon passage from the tailings to the atmosphere to allow for decay of 222 Rn within the cover. The depth of cover necessary to reduce the escaping radon flux to the prescribed level is to be determined by calculation, and requires precise knowledge of the radon diffusion coefficient in the covering media. A Radon Attenuation Test Facility was developed to determine rates of radon diffusion through candidate cover materials. This paper describes this facility and its application for determining the influence of physical properties of the soil column on the radon diffusion coefficient

  16. Microscale mineralogical characterization of As, Fe, and Ni in uranium mine tailings

    Science.gov (United States)

    Essilfie-Dughan, Joseph; Hendry, M. Jim; Warner, Jeff; Kotzer, Tom

    2012-11-01

    Uranium (U) ores can contain high concentrations of elements of concern (EOCs), such as arsenic (As) and nickel (Ni) present in sulfide and arsenide minerals. The U in these ores is often solubilized by adding H2SO4 to attain a pH ∼1 under oxic conditions. This process releases some EOCs from the primary minerals into solution. The barren raffinate (solution remaining after U extraction) is subsequently neutralized with Ca(OH)2 to a terminal pH of ∼10.5, resulting in a reduction in the aqueous concentrations of the EOCs. These neutralized raffinates are mixed with the non-reacted primary minerals and discharged as tailing into tailings management facilities (TMFs). To aid in the accurate characterization and quantification of the mineralogical controls on the concentrations of EOCs in the tailings porewater, their spatial distribution and speciation were studied at the micron scale in tailings samples collected from the Deilmann U Tailings Management Facility (DTMF), northern Saskatchewan, Canada. Backscattered electron images of the tailings samples generated using an electron microprobe show the presence of nodules (10-200 μm size) surrounded by bright rims. Wavelength dispersive spectrometric (WDS) and synchrotron-based micro-X-ray fluorescence (μ-XRF) elemental mapping show that the nodules are dominated by Ca and S (as gypsum) and the bright rims are dominated by Fe, As, and Ni. Micro-X-ray absorption near-edge structure (μ-XANES) spectra collected within and near the rims indicate that the Fe and Ni are present mainly in the +3 and +2 oxidation states, respectively; for As, the +5 oxidation state dominates but significant amounts of the +3 oxidation state are present in some areas. Linear combination fit analyses of the K-edges for the Fe, As, and Ni μ-XANES spectra to reference compounds suggest the Fe in the rims is present as ferrihydrite with As and Ni are adsorbed to it. Energy dispersive spectrometric (EDS) data indicate that isolated, highly

  17. Automated registration of tail bleeding in rats.

    Science.gov (United States)

    Johansen, Peter B; Henriksen, Lars; Andresen, Per R; Lauritzen, Brian; Jensen, Kåre L; Juhl, Trine N; Tranholm, Mikael

    2008-05-01

    An automated system for registration of tail bleeding in rats using a camera and a user-designed PC-based software program has been developed. The live and processed images are displayed on the screen and are exported together with a text file for later statistical processing of the data allowing calculation of e.g. number of bleeding episodes, bleeding times and bleeding areas. Proof-of-principle was achieved when the camera captured the blood stream after infusion of rat whole blood into saline. Suitability was assessed by recording of bleeding profiles in heparin-treated rats, demonstrating that the system was able to capture on/off bleedings and that the data transfer and analysis were conducted successfully. Then, bleeding profiles were visually recorded by two independent observers simultaneously with the automated recordings after tail transection in untreated rats. Linear relationships were found in the number of bleedings, demonstrating, however, a statistically significant difference in the recording of bleeding episodes between observers. Also, the bleeding time was longer for visual compared to automated recording. No correlation was found between blood loss and bleeding time in untreated rats, but in heparinized rats a correlation was suggested. Finally, the blood loss correlated with the automated recording of bleeding area. In conclusion, the automated system has proven suitable for replacing visual recordings of tail bleedings in rats. Inter-observer differences can be eliminated, monotonous repetitive work avoided, and a higher through-put of animals in less time achieved. The automated system will lead to an increased understanding of the nature of bleeding following tail transection in different rodent models.

  18. Monte Carlo-Based Tail Exponent Estimator

    Czech Academy of Sciences Publication Activity Database

    Baruník, Jozef; Vácha, Lukáš

    2010-01-01

    Roč. 2010, č. 6 (2010), s. 1-26 R&D Projects: GA ČR GA402/09/0965; GA ČR GD402/09/H045; GA ČR GP402/08/P207 Institutional research plan: CEZ:AV0Z10750506 Keywords : Hill estimator * α-stable distributions * tail exponent estimation Subject RIV: AH - Economics http://library.utia.cas.cz/separaty/2010/E/barunik-0342493.pdf

  19. Prelude to THEMIS tail conjunction study

    Directory of Open Access Journals (Sweden)

    A. T. Y. Lui

    2007-05-01

    Full Text Available A close conjunction of several satellites (LANL, GOES, Polar, Geotail, and Cluster distributed from the geostationary altitude to about 16 RE downstream in the tail occurred during substorm activity as indicated by global auroral imaging and ground-based magnetometer data. This constellation of satellites resembles what is planned for the THEMIS (Time History of Events and Macroscopic Interactions during Substorms mission to resolve the substorm controversy on the location of the substorm expansion onset region. In this article, we show in detail the dipolarization and dynamic changes seen by these satellites associated with two onsets of substorm intensification activity. In particular, we find that dipolarization at ~16 RE downstream in the tail can occur with dawnward electric field and without plasma flow, just like some near-Earth dipolarization events reported previously. The spreading of substorm disturbances in the tail coupled with complementary ground observations indicates that the observed time sequence on the onsets of substorm disturbances favors initiation in the near-Earth region for this THEMIS-like conjunction.

  20. Forecast Combination under Heavy-Tailed Errors

    Directory of Open Access Journals (Sweden)

    Gang Cheng

    2015-11-01

    Full Text Available Forecast combination has been proven to be a very important technique to obtain accurate predictions for various applications in economics, finance, marketing and many other areas. In many applications, forecast errors exhibit heavy-tailed behaviors for various reasons. Unfortunately, to our knowledge, little has been done to obtain reliable forecast combinations for such situations. The familiar forecast combination methods, such as simple average, least squares regression or those based on the variance-covariance of the forecasts, may perform very poorly due to the fact that outliers tend to occur, and they make these methods have unstable weights, leading to un-robust forecasts. To address this problem, in this paper, we propose two nonparametric forecast combination methods. One is specially proposed for the situations in which the forecast errors are strongly believed to have heavy tails that can be modeled by a scaled Student’s t-distribution; the other is designed for relatively more general situations when there is a lack of strong or consistent evidence on the tail behaviors of the forecast errors due to a shortage of data and/or an evolving data-generating process. Adaptive risk bounds of both methods are developed. They show that the resulting combined forecasts yield near optimal mean forecast errors relative to the candidate forecasts. Simulations and a real example demonstrate their superior performance in that they indeed tend to have significantly smaller prediction errors than the previous combination methods in the presence of forecast outliers.

  1. Tailings management for the twenty-first century

    International Nuclear Information System (INIS)

    Frost, S.E.

    1996-01-01

    The evolution of tailings management at Saskatchewan uranium mines is traced from the fifties to the nineties. Some of the problems with past systems are discussed. The new tailings systems now being proposed for the new operations currently undergoing environmental assessment in Saskatchewan are examined in detail. These new systems represent a change in tailings management philosophy, from keeping tailings high and dry on the surface, to placement of tailings in a low-energy regime within the water table. There they are removed from the active surface environment, avoiding future erosion problems, with a reduced likelihood of suffering intrusion from future human or animal activities. (author). 16 refs., 5 figs

  2. Differences between two subgroups of low back pain patients in lumbopelvic rotation and symmetry in the erector spinae and hamstring muscles during trunk flexion when standing.

    Science.gov (United States)

    Kim, Min-hee; Yoo, Won-gyu; Choi, Bo-ram

    2013-04-01

    The present study was performed to examine lumbopelvic rotation and to identify asymmetry of the erector spinae and hamstring muscles in people with and without low back pain (LBP). The control group included 16 healthy subjects, the lumbar-flexion-rotation syndrome LBP group included 17 subjects, and the lumbar-extension-rotation syndrome LBP group included 14 subjects. Kinematic parameters were recorded using a 3D motion-capture system, and electromyography parameters were measured using a Noraxon TeleMyo 2400T. The two LBP subgroups showed significantly more lumbopelvic rotation during trunk flexion in standing than did the control group. The muscle activity and flexion-relaxation ratio asymmetries of the erector spinae muscles in the lumbar-flexion-rotation syndrome LBP group were significantly greater than those in the control group, and the muscle activity and flexion-relaxation ratio asymmetry of the hamstring muscles in the lumbar-extension-rotation syndrome LBP group were significantly greater than those in the control group. Imbalance or asymmetry of passive tissue could lead to asymmetry of muscular activation. Muscle imbalance can cause asymmetrical alignment or movements such as unexpected rotation. The results showed a greater increase in lumbopelvic rotation during trunk flexion in standing among the lumbar-flexion-rotation syndrome and lumbar-extension-rotation syndrome LBP groups compared with the control group. The differences between the two LBP subgroups may be a result of imbalance and asymmetry in erector spinae and hamstring muscle properties. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. The role of the faceguard in the production of flexion injuries to the cervical spine in football.

    Science.gov (United States)

    Melvin, W J; Dunlop, H W; Hetherington, R F; Kerr, J W

    1965-11-20

    The precise role of the single-bar face mask in producing major flexion violence to the cervical spine has been studied by review of game movies, analysis of the radiographs and detailed interviews with two players who sustained fractures of cervical spine. The single-bar face mask can become fixed in the ground, thereby forcing a runner's head down onto his chest as the trunk moves forward. Preventive measures embodying modifications in the face mask, strict coaching in football techniques and the institution of safety factors in the playing rules are proposed. Appreciation of the mechanism of injury is urged in order to encourage careful inspection of protective head gear as well as to direct the attention of team physicians to the possibility of serious flexion injury to the cervical spine occurring without dramatic evidence. This report is not a plea for abandonment of the face mask but rather a suggestion for careful selection of a safe and efficient mask.

  4. Post-operative Hypertension following Correction of Flexion Deformity of the Knees in a Spastic Diplegic Child: A Case Report

    Directory of Open Access Journals (Sweden)

    Vipin Mohan

    2016-11-01

    Full Text Available An adolescent boy with spastic diplegic cerebral palsy presented with crouch gait. He had bilateral severe flexion deformities of knees and hips. He was treated with single event multilevel surgery for the correction of deformities. Surgical procedures included bilateral adductor release, iliopsoas lengthening, bilateral femoral shortening and patella plication. Persistent hypertension was noted in the post-operative period. All causes of secondary hypertension were ruled out. Having persistent hypertension following the femoral shortening procedure is unusual. Antihypertensive medication controlled his blood pressure 15 months after surgery. Hypertension following correction of knee flexion deformity and limb lengthening is well known. Hypertension has not been described with the shortening osteotomy of the femur. Hypertension is a rare complication following the corrective surgery for the treatment of crouch gait. Blood pressure should be monitored during the post-operative period to detect such a rare complication.

  5. Using verbal instructions to influence lifting mechanics - Does the directive "lift with your legs, not your back" attenuate spinal flexion?

    Science.gov (United States)

    Beach, Tyson A C; Stankovic, Tatjana; Carnegie, Danielle R; Micay, Rachel; Frost, David M

    2018-02-01

    "Use your legs" is commonly perceived as sound advice to prevent lifting-related low-back pain and injuries, but there is limited evidence that this directive attenuates the concomitant biomechanical risk factors. Body segment kinematic data were collected from 12 men and 12 women who performed a laboratory lifting/lowering task after being provided with different verbal instructions. The main finding was that instructing participants to lift "without rounding your lower back" had a greater effect on the amount of spine flexion they exhibited when lifting/lowering than instructing them to lift "with your legs instead of your back" and "bend your knees and hips". It was concluded that if using verbal instructions to discourage spine flexion when lifting, the instructions should be spine- rather than leg-focused. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Tailings dams from the perspective of conventional dam engineering

    International Nuclear Information System (INIS)

    Szymanski, M.B.

    1999-01-01

    A guideline intended for conventional dams such as hydroelectric, water supply, flood control, or irrigation is used sometimes for evaluating the safety of a tailings dam. Differences between tailings dams and conventional dams are often substantial and, as such, should not be overlooked when applying the techniques or safety requirements of conventional dam engineering to tailings dams. Having a dam safety evaluation program developed specifically for tailings dams is essential, if only to reduce the chance of potential errors or omissions that might occur when relying on conventional dam engineering practice. This is not to deny the merits of using the Canadian Dam Safety Association Guidelines (CDSA) and similar conventional dam guidelines for evaluating the safety of tailings dams. Rather it is intended as a warning, and as a rationale underlying basic requirement of tailings dam emgineering: specific experience in tailings dams is essential when applying conventional dam engineering practice. A discussion is included that focuses on the more remarkable tailings dam safety practics. It is not addressed to a technical publications intended for such dams, or significantly different so that the use of conventional dam engineering practice would not be appropriate. The CDSA Guidelines were recently revised to include tailings dams. But incorporating tailings dams into the 1999 revision of the CDSA Guidelines is a first step only - further revision is necessary with respect to tailings dams. 11 refs., 2 tabs

  7. Placement of radium/barium sludges in tailings areas

    International Nuclear Information System (INIS)

    Murphy, K.L.; Multamaki, G.E.

    1980-01-01

    Currently radium is removed from uranium mining and milling effluents by the addition of barium chloride to precipitate the radium as radium/barium sulphate. The precipitate is allowed to settle in sedimentation basins prior to discharge of the effluent. The sedimentation basins are not suitable for final disposal of the sludge, and placement of the sludges in the tailings area has been proposed. The geochemical environment of fresh tailings areas was characterized as an acidic, oxidized surface zone underlain by an alkaline, reduced zone comprising the rest of the tailings. The quantity of sludge produced was estimated to be small relative to the quantity of tailings, and therefor a relatively small amount of radium would be added to the tailings disposal area by the addition of sludge. To confirm whether sludge addition affected radionuclide solubilization, laboratory leaching tests were conducted on slurries of acid leach tailings, and sludge-tailings mixtures. Radium in the (Ra,Ba)SO 4 sludge was at least as stable as radium in the tailings, and the sludge was able to absorb radium released from the tailings. The addition of sludge did not affect uranium and thorium solubilization. From these results it appears that the placement of sludge in tailings areas would not adversely affect the stability of radionuclides in the tailings or sludge. (auth)

  8. Polymer aids for settling and filtration of oil sands tailings

    Energy Technology Data Exchange (ETDEWEB)

    Wang, X. [Alberta Univ., Edmonton, AB (Canada). Dept. of Chemical and Materials Engineering; Energy Resources Conservation Board, Calgary, AB (Canada). Oil Sands Section; Xu, Z.; Masliyah, J.H. [Alberta Univ., Edmonton, AB (Canada). Dept. of Chemical and Materials Engineering

    2008-07-01

    Oil sand tailings are segregated into coarse and fine tailings. High volumes of toxic fluids and tailings are created in the process. Tailings ponds are an environmental risk with high operating and maintenance costs. Current commercial technologies uses chemical additions to create recycled water and composite tailings (CT). Researchers are now investigating centrifuged and dry mature fine tailings (MFT). Filtration processes with flocculants are used to separate the tailings into warm recycle water and dried cakes that can be used in reclamation processes. Studies are being conducted to find a polymer than can effectively flocculate and filter whole oil sands tailings. The filtration procedure uses pressure to produce released water. Polymers include magnafloc and Al-PAM polymer concentrations are used in slurry masses. Tests have been conducted to determine the settling rates of the polymers. The tests showed that Al-PAM filtered the tailings effectively. Paraffinic froth treatment tests have also been conducted to determine settling rates. A cake produced with froth treatment tailings of Al-PAM 400 ppm had a water content 42.5 wt per cent. The tests showed that while Magnafloc 1011 is a good settling aid, but a poor filtration addition. Al-PAM aided in both the flocculation and filtration processes. Higher Al-PAM dosages are needed for froth treatment tailings processes. It was concluded that dry cakes are produced with the addition of Al-PAM. tabs., figs.

  9. Asphalt emulsion sealing of uranium mill tailings. 1979 annual report

    International Nuclear Information System (INIS)

    Hartley, J.N.; Koehmstedt, P.L.; Esterl, D.J.; Freeman, H.D.

    1980-06-01

    Uranium mill tailings are a source of low-level radiation and radioactive materials that may be released into the environment. Stabilization or disposal of these tailings in a safe and environmentally sound way is necessary to minimize radon exhalation and other radioactive releases. One of the most promising concepts for stabilizing uranium tailings is being investigated at the Pacific Northwest Laboratory: the use of asphalt emulsion to contain radon and other potentially hazardous materials in uranium tailings. Results of these studies indicate that radon flux from uranium tailings can be reduced by greater than 99% by covering the tailings with an asphalt emulsion that is poured on or sprayed on (3.0 to 7.0 mm thick), or mixed with some of the tailings and compacted to form an admixture seal (2.5 to 15.2 cm) containing 18 wt % residual asphalt

  10. A Note on Upper Tail Behavior of Liouville Copulas

    Directory of Open Access Journals (Sweden)

    Lei Hua

    2016-11-01

    Full Text Available The family of Liouville copulas is defined as the survival copulas of multivariate Liouville distributions, and it covers the Archimedean copulas constructed by Williamson’s d-transform. Liouville copulas provide a very wide range of dependence ranging from positive to negative dependence in the upper tails, and they can be useful in modeling tail risks. In this article, we study the upper tail behavior of Liouville copulas through their upper tail orders. Tail orders of a more general scale mixture model that covers Liouville distributions is first derived, and then tail order functions and tail order density functions of Liouville copulas are derived. Concrete examples are given after the main results.

  11. Big picture thinking in oil sands tailings disposal

    Energy Technology Data Exchange (ETDEWEB)

    Boswell, J. [Thurber Engineering Ltd., Calgary, AB (Canada)

    2010-07-01

    This PowerPoint presentation discussed methods of disposing oil sands tailings. Oil sands operators are currently challenged by a variety of legislative and environmental factors concerning the creation and disposal of oil sands tailings. The media has focused on the negative ecological impact of oil sands production, and technical issues are reducing the effect of some mitigation processes. Operators must learn to manage the interface between tailings production and removal, the environment, and public opinion. The successful management of oil sand tailings will include procedures designed to improve reclamation processes, understand environmental laws and regulations, and ensure that the cumulative impacts of tailings are mitigated. Geotechnical investigations, engineering designs and various auditing procedures can be used to develop tailings management plans. Environmental screening and impact assessments can be used to develop sustainable solutions. Public participation and environmental mediation is needed to integrate the public, environmental and technical tailings management strategies. Operators must ensure public accountability for all stakeholders. tabs., figs.

  12. Fat-tailed risk about climate change and climate policy

    International Nuclear Information System (INIS)

    Hwang, In Chang; Tol, Richard S.J.; Hofkes, Marjan W.

    2016-01-01

    This paper investigates the role of emissions control in welfare maximization under fat-tailed risk about climate change. We provide a classification of fat tails and discuss the effect of fat-tailed risk on climate policy. One of the main findings is that emissions control may prevent the “strong” tail-effect from arising, at least under some conditions such as bounded temperature increases, low risk aversion, low damage costs, and bounded utility function. More specifically, the fat-tailed risk with respect to a climate parameter does not necessarily lead to an unbounded carbon tax. In this case, the basic principle of cost-benefit analysis maintains its applicability. - Highlights: • A fat tail is classified and the tail effect on climate policy is discussed. • The optimal carbon tax is not necessarily unbounded. • The basic principle of cost-benefit analysis maintains its applicability. • This is a numerical confirmation of the recent theoretical research.

  13. Age-Related Differences in Motor Coordination during Simultaneous Leg Flexion and Finger Extension: Influence of Temporal Pressure

    OpenAIRE

    Hussein, Tarek; Yiou, Eric; Larue, Jacques

    2013-01-01

    Although the effect of temporal pressure on spatio-temporal aspects of motor coordination and posture is well established in young adults, there is a clear lack of data on elderly subjects. This work examined the aging-related effects of temporal pressure on movement synchronization and dynamic stability. Sixteen young and eleven elderly subjects performed series of simultaneous rapid leg flexions in an erect posture paired with ipsilateral index-finger extensions, minimizing the difference b...

  14. Influence of increasing knee flexion angle on knee-ankle varus stress during single-leg jump landing

    Directory of Open Access Journals (Sweden)

    Mariam A. Ameer, PhD

    2017-12-01

    Full Text Available Objectives: The primary aim of this study was to identify the relationship between the peak knee flexion angle and knee-ankle varus stress in the landing phase of the single-leg jump during running. Methods: Fifteen male handball players from the first Saudi Arabian handball team were incorporated in this study. Each player performed a single-leg jump-land after running a fixed distance of 450 cm. The data were measured using a 3D motion analysis system. The maximum knee flexion angle, knee varus angle, centre of pressure pathway in the medio-lateral direction, and ankle varus moment were measured. Results: The Pearson Product Moment Correlation showed that a greater knee flexion angle was related to a greater lateral displacement of the centre of pressure (r = 0.794, P = 0.000, a greater ankle varus moment (r = 0.707, P = 0.003, and a greater knee varus angle (r = 0.753, P = 0.001. In addition, the greater ankle varus moment was related to the greater lateral displacement of the centre of pressure (r = 0.734, P = 0.002. Conclusions: These findings may help physical therapists and conditioning professionals to understand the impact of increasing knee flexion angle on the lower limb joints. Such findings may help to develop training protocols for enhancing the lateral body reaction during the landing phase of the single-leg jump, which may protect the knee and ankle joints from excessive varus stresses. Keywords: 3D motion analysis, Ankle kinetic, Centre of pressure pathway, Handball playing, Knee kinematic, Single-leg jump

  15. Walking like dinosaurs: chickens with artificial tails provide clues about non-avian theropod locomotion.

    Science.gov (United States)

    Grossi, Bruno; Iriarte-Díaz, José; Larach, Omar; Canals, Mauricio; Vásquez, Rodrigo A

    2014-01-01

    Birds still share many traits with their dinosaur ancestors, making them the best living group to reconstruct certain aspects of non-avian theropod biology. Bipedal, digitigrade locomotion and parasagittal hindlimb movement are some of those inherited traits. Living birds, however, maintain an unusually crouched hindlimb posture and locomotion powered by knee flexion, in contrast to the inferred primitive condition of non-avian theropods: more upright posture and limb movement powered by femur retraction. Such functional differences, which are associated with a gradual, anterior shift of the centre of mass in theropods along the bird line, make the use of extant birds to study non-avian theropod locomotion problematic. Here we show that, by experimentally manipulating the location of the centre of mass in living birds, it is possible to recreate limb posture and kinematics inferred for extinct bipedal dinosaurs. Chickens raised wearing artificial tails, and consequently with more posteriorly located centre of mass, showed a more vertical orientation of the femur during standing and increased femoral displacement during locomotion. Our results support the hypothesis that gradual changes in the location of the centre of mass resulted in more crouched hindlimb postures and a shift from hip-driven to knee-driven limb movements through theropod evolution. This study suggests that, through careful experimental manipulations during the growth phase of ontogeny, extant birds can potentially be used to gain important insights into previously unexplored aspects of bipedal non-avian theropod locomotion.

  16. Walking like dinosaurs: chickens with artificial tails provide clues about non-avian theropod locomotion.

    Directory of Open Access Journals (Sweden)

    Bruno Grossi

    Full Text Available Birds still share many traits with their dinosaur ancestors, making them the best living group to reconstruct certain aspects of non-avian theropod biology. Bipedal, digitigrade locomotion and parasagittal hindlimb movement are some of those inherited traits. Living birds, however, maintain an unusually crouched hindlimb posture and locomotion powered by knee flexion, in contrast to the inferred primitive condition of non-avian theropods: more upright posture and limb movement powered by femur retraction. Such functional differences, which are associated with a gradual, anterior shift of the centre of mass in theropods along the bird line, make the use of extant birds to study non-avian theropod locomotion problematic. Here we show that, by experimentally manipulating the location of the centre of mass in living birds, it is possible to recreate limb posture and kinematics inferred for extinct bipedal dinosaurs. Chickens raised wearing artificial tails, and consequently with more posteriorly located centre of mass, showed a more vertical orientation of the femur during standing and increased femoral displacement during locomotion. Our results support the hypothesis that gradual changes in the location of the centre of mass resulted in more crouched hindlimb postures and a shift from hip-driven to knee-driven limb movements through theropod evolution. This study suggests that, through careful experimental manipulations during the growth phase of ontogeny, extant birds can potentially be used to gain important insights into previously unexplored aspects of bipedal non-avian theropod locomotion.

  17. Reliability and validity of a brief method to assess nociceptive flexion reflex (NFR) threshold.

    Science.gov (United States)

    Rhudy, Jamie L; France, Christopher R

    2011-07-01

    The nociceptive flexion reflex (NFR) is a physiological tool to study spinal nociception. However, NFR assessment can take several minutes and expose participants to repeated suprathreshold stimulations. The 4 studies reported here assessed the reliability and validity of a brief method to assess NFR threshold that uses a single ascending series of stimulations (Peak 1 NFR), by comparing it to a well-validated method that uses 3 ascending/descending staircases of stimulations (Staircase NFR). Correlations between the NFR definitions were high, were on par with test-retest correlations of Staircase NFR, and were not affected by participant sex or chronic pain status. Results also indicated the test-retest reliabilities for the 2 definitions were similar. Using larger stimulus increments (4 mAs) to assess Peak 1 NFR tended to result in higher NFR threshold estimates than using the Staircase NFR definition, whereas smaller stimulus increments (2 mAs) tended to result in lower NFR threshold estimates than the Staircase NFR definition. Neither NFR definition was correlated with anxiety, pain catastrophizing, or anxiety sensitivity. In sum, a single ascending series of electrical stimulations results in a reliable and valid estimate of NFR threshold. However, caution may be warranted when comparing NFR thresholds across studies that differ in the ascending stimulus increments. This brief method to assess NFR threshold is reliable and valid; therefore, it should be useful to clinical pain researchers interested in quickly assessing inter- and intra-individual differences in spinal nociceptive processes. Copyright © 2011 American Pain Society. Published by Elsevier Inc. All rights reserved.

  18. The use of forced flexion/extension views in the obtunded trauma patient

    Energy Technology Data Exchange (ETDEWEB)

    Griffiths, Harry J.; Wagner, Jason; Anglen, Jeff; Bunn, Paul; Metzler, Michael [Department of Radiology, Departments of Radiology/Orthopaedics and Surgery, University of Missouri-Columbia, One Hospital Drive - DC069.10, Columbia, MO 65212 (United States)

    2002-10-01

    To determine whether forced flexion/extension (F/E) films for ''clearing'' the cervical spine in unconscious or semiconscious patients are useful or actually dangerous.Design and patients. Of 810 patients admitted for blunt trauma over a 5-year period, 479 patients whose films and charts were available received passive F/E film views of the cervical spine. Of these, 447 were reviewed retrospectively in masked fashion for any exacerbation of neurological changes subsequent to the procedure and with respect to the final neurological status at discharge.Results. Twenty-nine patients (6%) had various abnormalities including fractures and ligamentous injuries seen on the initial films. Following forced F/E films no change was made in the diagnosis of 23 patients. Of the remaining six patients, two required no treatment, two only required the use of a collar but two did have surgical intervention, this decision being based on the findings seen in the initial films. However, 285 films (59%) were judged inadequate due either to inadequate F/E (150 patients, 31%) or poor visualization (194 patients, 40%). There were three false positives all subsequently cleared by other studies and there were no false negatives. From the chart review, there were no complications or deaths attributable to the procedure.Conclusion. Although we were unable to find any complication or deaths directly attributable to the procedure, the clinicians abandoned passive F/E views in obtunded patients on the grounds of expense. Our present method of ''clearing'' a cervical spine in an obtunded patient is a cross-table lateral radiograph followed by a high-resolution thin-slice CT scan with sagittal and coronal reconstruction. We are against the use of routine MRI studies and of a forced F/E view in these patients. (orig.)

  19. Knee flexion contractures in institutionalized elderly: prevalence, severity, stability, and related variables.

    Science.gov (United States)

    Mollinger, L A; Steffen, T M

    1993-07-01

    The purpose of this study was to document the prevalence, severity, and progression of knee flexion contractures (KFCs) in a population of institutionalized elderly and to identify relationships between knee extension and other variables. The subjects were 112 nursing home residents who exhibited a broad range of ambulation and cognitive function abilities. Data were collected initially (T1) and after a 10-month period (T2). Only 25% of the population had extension in the 0- to 5-degree (lacking full extension) range bilaterally at T1 and T2, leaving the majority of subjects with some degree of unilateral KFC. Most of the subjects with a KFC greater than 20 degrees were nonambulatory and had a significantly higher occurrence of resistance to motion than did nonambulators with a KFC of less than 20 degrees. Knee extension measurements did not change in most subjects between T1 and T2. The knees that did show a change in KFC (either an increase or a decrease) had a significantly higher occurrence of resistance to passive motion than did other knees. Compared with the subjects who gained extension, the subjects who lost extension over the study period more frequently had minimal KFC at T1, were ambulatory at T1, showed a regression in ambulation at T2, and developed resistance to motion at T2. The data confirmed significant positive correlations between degree of KFC and presence of resistance to passive knee motion, cognitive impairment, impaired ambulation, and presence of knee pain. Physical therapy assessment and intervention may be appropriate in nonambulatory nursing home residents with resistance to passive motion, residents with KFC approaching 20 degrees, and ambulatory residents with minimal KFC who develop resistance and begin to regress in ambulation. Several areas for future study are suggested.

  20. Infrapatellar plica of the knee: Revisited with MR arthrographies undertaken in the knee flexion position mimicking operative arthroscopic posture

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Young Han; Song, Ho-Taek; Kim, Sungjun [Department of Radiology and Research Institute of Radiological Science, Yonsei University College of Medicine, 250 Seongsanno, Seodaemun-gu, Seoul 120-752 (Korea, Republic of); Kim, Sung-Jae [Department of Orthopedic Surgery and Arthroscopic Surgery Unit, Yonsei University College of Medicine (Korea, Republic of); Suh, Jin-Suck, E-mail: jss@yuhs.ac [Department of Radiology and Research Institute of Radiological Science, Yonsei University College of Medicine, 250 Seongsanno, Seodaemun-gu, Seoul 120-752 (Korea, Republic of)

    2012-10-15

    Purpose: To describe the appearance of the infrapatellar plica (IPP) on magnetic resonance arthrography (MRA) taken in 70° knee flexion, corresponding to the arthroscopic posture. Materials and methods: Twenty-two patients (23 knee joints) who underwent MRA with 70° knee flexion were enrolled. All patients underwent MRA with 70° knee flexion to simulate operative arthroscopy. The images included fat-suppressed T1-weighted spin echo axial, sagittal, and coronal images. The visualization and morphology of the IPP were retrospectively assessed by two musculoskeletal radiologists. Results: The IPP was demonstrated in 78.3% (n = 18/23) and was best visualized on the sagittal section through the intercondylar notch. The IPP manifested as a linear hypointense structure with variable thicknesses. The intercondylar component was delineated clearly, arising from the anterior intercondylar notch in parallel with the ACL and curving gently downward to attach to the infrapatellar fat pad. On the other hand, the Hoffa's fat pad component was not depicted clearly. The morphology of the IPP was either a separate type (60.9%) or a split type (17.4%). Conclusion: The IPPs can be visualized with a high rate of detection and various morphologic appearances must be appreciated under the review of a flexed knee MRA.

  1. An Accurate Full-flexion Anterolateral Portal for Needle Placement in the Knee Joint With Dry Osteoarthritis.

    Science.gov (United States)

    Hussein, Mohamed

    2017-07-01

    Accurate delivery of an injection into the intra-articular space of the knee is achieved in only two thirds of knees when using the standard anterolateral portal. The use of a modified full-flexion anterolateral portal provides a highly accurate, less painful, and more effective method for reproducible intra-articular injection without the need for ultrasonographic or fluoroscopic guidance in patients with dry osteoarthritis of the knee. The accuracy of needle placement was assessed in a prospective series of 140 consecutive injections in patients with symptomatic degenerative knee arthritis without clinical knee effusion. Procedural pain was determined using the Numerical Rating Scale. The accuracy rates of needle placement were confirmed with fluoroscopic imaging to document the dispersion pattern of injected contrast material. Using the standard anterolateral portal, 52 of 70 injections were confirmed to have been placed in the intra-articular space on the first attempt (accuracy rate, 74.2%). Using the modified full-flexion anterolateral portal, 68 of 70 injections were placed in the intra-articular space on the first attempt (accuracy rate, 97.1%; P = 0.000). This study revealed that using the modified full-flexion anterolateral portal for injections into the knee joint resulted in more accurate and less painful injections than those performed by the same orthopaedic surgeon using the standard anterolateral portal. In addition, the technique offered therapeutic delivery into the joint without the need for fluoroscopic confirmation. Therapeutic Level II.

  2. Chapter 2. The history of uranium tailings formation in the North of Tajikistan, their current condition. 2.4. Degmai uranium tailings

    International Nuclear Information System (INIS)

    Khakimov, N.; Nazarov, Kh.M.; Mirsaidov, I.U.

    2012-01-01

    Present article is devoted to Degmai uranium tailings. The history of Degmai uranium tailings is presented. The current condition of uranium tailings is described. During the last 6-7 years, together with IAEA experts, monitoring is permanently carried out and the tailings influence on the environment is defined. Radiation and dosimetric investigation results from Degmai tailing' surface (June 2006) are considered.

  3. Taming the tailings : dead ducks notwithstanding, extensive research is underway to deal with oilsands tailings in a more efficient manner

    Energy Technology Data Exchange (ETDEWEB)

    Collison, M.

    2008-09-15

    Research is now being conducted to reduce the environmental impacts of oil sands tailing ponds. Alberta's oil sands region contains an estimated 60 km{sup 2} of tailings ponds, which serve as holding basins for recycled water as well as collection sites for materials used in reclamation activities. The ponds contain residual bitumen, production chemicals, and minerals. While some of the water in the ponds can be re-used, mature fine tailings must be contained behind dikes. Every barrel of bitumen produced by the industry results in the creation of 1.5 barrels of mature fine tailings. Natural Resources Canada's CANMET Energy Technology Centre is currently conducting a research program with the University of Alberta to reduce the amounts of tailings produced by the industry. Options for dry stackable tailings are being explored, as well as methods of using the tailings to enhance various oil sands processes. It is hoped that the dry, stackable tailings can be used to help reclaim and rebuild Boreal regions impacted by the oil sands industry. The program is gaining interest due to concerns that leakages from the tailings ponds may pollute aquifers and rivers in a region noted for its water shortages. Research teams are also investigating the use of flocculants to create heavy non-segregated tailings. Researchers are also examining methods of recovering hydrocarbons, titanium, and zircon from the tailings. 3 figs.

  4. Tail docking in pigs: a review on its short- and long-term consequences and effectiveness in preventing tail biting

    Directory of Open Access Journals (Sweden)

    Eleonora Nannoni

    2014-02-01

    Full Text Available In spite of European legislation attempting to limit this practice, tail docking is nowadays the only preventive measure against tail biting which is widely adopted by farmers. Docking consists in amputating, usually without anaesthesia or analgesia, the distal part of the tail, in order to reduce its attractiveness and to sensitize it, increasing avoidance behaviour in the bitten pig. Tail docking results in both acute and chronic effects on pig welfare, and its effectiveness in preventing tail biting is limited, since it reduces the symptoms of a behavioural disorder, but does not address the underlying causes. The aim of the present paper is to review the available literature on the effects of tail docking on swine welfare. Although from a practical standpoint the welfare risks arising from tail docking may appear to be negligible compared to those arising during and after tail biting outbreaks, it should be considered that, apart from acute physiological and behavioural responses, tail docking may also elicit long-term effects on weight gain, tail stump sensitivity and animal freedom to express their normal behaviour. Such chronic effects have been poorly investigated so far. Besides, studies evaluating the effectiveness of anaesthetics or analgesic treatments are often conflicting. Within this framework, further research is recommended in order to reduce the acute and chronic pain and discomfort experienced by the animals, until preventive measures (e.g., environmental enrichment, stocking densities are broadly adopted to prevent tail biting.

  5. Isolated galaxies

    International Nuclear Information System (INIS)

    Einasto, Maret

    1990-01-01

    To test for the possible presence of really isolated galaxies, which form a randomly distributed population in voids, we compare the distribution of most isolated galaxies in an observed sample with distributions of the same number of random points using the nearest neighbour test. The results show that the random population of really isolated galaxies does not exist - even the most isolated galaxies are connected with systems of galaxies, forming their outlying parts. (author)

  6. Engineering assessment of inactive uranium mill tailings, Lakeview Site, Lakeview, Oregon. Phase II, Title I

    International Nuclear Information System (INIS)

    1977-12-01

    Results are reported from an engineering assessment of the problems resulting from the existence of radioactive uranium mill tailings at the Lakeview, Oregon site. Results are included from the analyses of soil, water, and other samples; radiometric measurements to determine areas with radium-contaminated materials; evaluation of resulting radiation exposures of individuals and nearby populations; investigation of site geology, hydrology, and meteorology; and evaluation and costing of alternative corrective actions. Radon gas release from the 130,000 tons of tailings at the Lakeview site constitutes the main environmental impact, which is minimal. The two alternative actions presented are maintenance of the site now that the ARCO reclamation program has been completed (Option I); and addition of stabilization cover to a minimum depth of 2 ft, improved fencing, and removal of a few isolated spots of contamination (Option II). The cost estimates for these options are $40,000 and $290,000, respectively

  7. Field performance assessment of synthetic liners for uranium tailings ponds: a status report

    International Nuclear Information System (INIS)

    Mitchell, D.H.; Spanner, G.E.

    1984-03-01

    The objective of this study is to provide a database to support US Nuclear Regulatory Commission (NRC) licensing of uranium tailings leachate isolation impoundments. This objective is being accomplished by determining the effectiveness of design, installation, and quality assurance practices associated with uranium mill tailings impoundments with flexible membrane liners. The program includes testing of chemical resistance and physical performance of liners, leak detection systems, and seam inspection techniques. This report presents the status of the program through September 1983. The report addresses impoundment design, installation, and inspection techniques used by the uranium milling industry. To determine the relative successes of these techniques, information has been collected from consultants, mill operators, and the synthetic liner industry. Progress in experimental tasks on chemical resistance of liners, physical properties of liners, and nondestructive examination of seams is reported. 25 references, 9 figures, 13 tables

  8. Understanding the enormous diversity of bacteriophages: the tailed phages that infect the bacterial family Enterobacteriaceae

    Science.gov (United States)

    Grose, Julianne H.; Casjens, Sherwood R.

    2014-01-01

    Bacteriophages are the predominant biological entity on the planet. The recent explosion of sequence information has made estimates of their diversity possible. We describe the genomic comparison of 337 fully sequenced tailed phages isolated on 18 genera and 31 species of bacteria in the Enterobacteriaceae. These phages were largely unambiguously grouped into 56 diverse clusters (32 lytic and 24 temperate) that have syntenic similarity over >50% of the genomes within each cluster, but substantially less sequence similarity between clusters. Most clusters naturally break into sets of more closely related subclusters, 78% of which are correlated with their host genera. The largest groups of related phages are superclusters united by genome synteny to lambda (81 phages) and T7 (51 phages). This study forms a robust framework for understanding diversity and evolutionary relationships of existing tailed phages, for relating newly discovered phages and for determining host/phage relationships. PMID:25240328

  9. Characterization of ten microsatellite loci in the Broad-tailed hummingbird (Selasphorus platycercus)

    Science.gov (United States)

    Oyler-McCance, Sara J.; Fike, Jennifer A.; Talley-Farnham, Tiffany; Engelman, Tena; Engelman, Fred

    2011-01-01

    The Broad-tailed Hummingbird (Selaphorus platycercus) breeds at higher elevations in the central and southern Rockies, eastern California, and Mexico and has been studied for 8 years in Rocky Mountain National Park, Colorado. Questions regarding the relatedness of Broad-tailed Hummingbirds banded together and then recaptured in close time proximity in later years led us to isolate and develop primers for 10 polymorphic microsatellite loci. In a screen of 25 individuals from a population in Rocky Mountain National Park, the 10 loci were found to have levels of variability ranging from two to 16 alleles. No loci were found to depart from linkage disequilibrium, although two loci revealed significant departures from Hardy–Weinberg equilibrium. These 10 microsatellite loci will be applicable for population genetic analyses, investigation of mating systems and relatedness, and may help gain insight into the migration timing and routes for this species.

  10. Metal mobilization under alkaline conditions in ash-covered tailings.

    Science.gov (United States)

    Lu, Jinmei; Alakangas, Lena; Wanhainen, Christina

    2014-06-15

    The aim of this study was to determine element mobilization and accumulation in mill tailings under alkaline conditions. The tailings were covered with 50 cm of fly ash, and above a sludge layer. The tailings were geochemically and mineralogically investigated. Sulfides, such as pyrrhotite, sphalerite and galena along with gangue minerals such as dolomite, calcite, micas, chlorite, epidote, Mn-pyroxene and rhodonite were identified in the unoxidized tailings. The dissolution of the fly ash layer resulted in a high pH (close to 12) in the underlying tailings. This, together with the presence of organic matter, increased the weathering of the tailings and mobilization of elements in the uppermost 47 cm of the tailings. All primary minerals were depleted, except quartz and feldspar which were covered by blurry secondary carbonates. Sulfide-associated elements such as Cd, Fe, Pb, S and Zn and silicate-associated elements such as Fe, Mg and Mn were released from the depletion zone and accumulated deeper down in the tailings where the pH decreased to circum-neutral. Sequential extraction suggests that Cd, Cu, Fe, Pb, S and Zn were retained deeper down in the tailings and were mainly associated with the sulfide phase. Calcium, Cr, K and Ni released from the ash layer were accumulated in the uppermost depletion zone of the tailings. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Oil sands tailings technology : understanding the impact to reclamation

    Energy Technology Data Exchange (ETDEWEB)

    Mamer, M. [Suncor Energy Inc., Fort McMurray, AB (Canada)

    2010-07-01

    This paper discussed tailings management techniques at oil sands mines and their effects on reclamation schedules and outcomes. The layer of mature fine tailings (MFT) that forms in tailings ponds does not settle within a reasonable time frame, requiring more and larger tailings ponds for storing MFT. Consolidated tailings (CT) technology was developed to accelerate the consolidation of MFT, although the process nonetheless takes decades. CT is produced from mixing tailings sand, gypsum, and MFT to create a mixture that will consolidate more quickly and release water. However, CT production is tied to the extraction process, making it applicable only when the plant is operational, and a precise recipe and accurate injection are required for CT to work. In tailings reduction operations (TRO), a new approach to tailings management, MFT is mixed with a polymer flocculant, deposited in thin layers, and allowed to dry. TRO has a significant advantage over CT in that the latter takes up to 30 years to consolidate to a trafficable surface compared to weeks for TRO. TRO allows MFT to be consumed more quickly than it is produced, reducing need to build more tailings ponds, operates independent of plant operations, accelerates the reclamation time frame, and offers enhanced flexibility in final tailings placement sites. TRO also creates a dry landscape, to which well established reclamation techniques can be applied. Dried MFT is a new material type, and research is exploring optimum reclamation techniques. 2 figs.

  12. Flexible histone tails in a new mesoscopic oligonucleosome model.

    Science.gov (United States)

    Arya, Gaurav; Zhang, Qing; Schlick, Tamar

    2006-07-01

    We describe a new mesoscopic model of oligonucleosomes that incorporates flexible histone tails. The nucleosome cores are modeled using the discrete surface-charge optimization model, which treats the nucleosome as an electrostatic surface represented by hundreds of point charges; the linker DNAs are treated using a discrete elastic chain model; and the histone tails are modeled using a bead/chain hydrodynamic approach as chains of connected beads where each bead represents five protein residues. Appropriate charges and force fields are assigned to each histone chain so as to reproduce the electrostatic potential, structure, and dynamics of the corresponding atomistic histone tails at different salt conditions. The dynamics of resulting oligonucleosomes at different sizes and varying salt concentrations are simulated by Brownian dynamics with complete hydrodynamic interactions. The analyses demonstrate that the new mesoscopic model reproduces experimental results better than its predecessors, which modeled histone tails as rigid entities. In particular, our model with flexible histone tails: correctly accounts for salt-dependent conformational changes in the histone tails; yields the experimentally obtained values of histone-tail mediated core/core attraction energies; and considers the partial shielding of electrostatic repulsion between DNA linkers as a result of the spatial distribution of histone tails. These effects are crucial for regulating chromatin structure but are absent or improperly treated in models with rigid histone tails. The development of this model of oligonucleosomes thus opens new avenues for studying the role of histone tails and their variants in mediating gene expression through modulation of chromatin structure.

  13. Phytomining for Artisanal Gold Mine Tailings Management

    Directory of Open Access Journals (Sweden)

    Baiq Dewi Krisnayanti

    2016-08-01

    Full Text Available Mine tailings are generally disposed of by artisanal and small scale gold miners in poorly constructed containment areas and this leads to environmental risk. Gold phytomining could be a possible option for tailings management at artisanal and small-scale gold mining (ASGM locations where plants accumulate residual gold in their above ground biomass. The value of metal recovered from plants could offset some of the costs of environmental management. Getting gold into plants has been repeatedly demonstrated by many research groups; however, a simple working technology to get gold out of plants is less well described. A field experiment to assess the relevance of the technology to artisanal miners was conducted in Central Lombok, Indonesia between April and June 2015. Tobacco was planted in cyanidation tailings (1 mg/kg gold and grown for 2.5 months before the entire plot area was irrigated with NaCN to induce metal uptake. Biomass was then harvested (100 kg, air dried, and ashed by miners in equipment currently used to ash activated carbon at the end of a cyanide leach circuit. Borax and silver as a collector metal were added to the tobacco ash and smelted at high temperature to extract metals from the ash. The mass of the final bullion (39 g was greater than the mass of silver used as a collector (31 g, indicating recovery of metals from the biomass through the smelt process. The gold yield of this trial was low (1.2 mg/kg dry weight biomass concentration, indicating that considerable work must still be done to optimise valuable metal recovery by plants at the field scale. However, the described method to process the biomass was technically feasible, and represents a valid technique that artisanal and small-scale gold miners are willing to adopt if the economic case is good.

  14. Dwarf Galaxies Swimming in Tidal Tails

    Science.gov (United States)

    2005-01-01

    This false-color infrared image from NASA's Spitzer Space Telescope shows little 'dwarf galaxies' forming in the 'tails' of two larger galaxies that are colliding together. The big galaxies are at the center of the picture, while the dwarfs can be seen as red dots in the red streamers, or tidal tails. The two blue dots above the big galaxies are stars in the foreground. Galaxy mergers are common occurrences in the universe; for example, our own Milky Way galaxy will eventually smash into the nearby Andromeda galaxy. When two galaxies meet, they tend to rip each other apart, leaving a trail, called a tidal tail, of gas and dust in their wake. It is out of this galactic debris that new dwarf galaxies are born. The new Spitzer picture demonstrates that these particular dwarfs are actively forming stars. The red color indicates the presence of dust produced in star-forming regions, including organic molecules called polycyclic aromatic hydrocarbons. These carbon-containing molecules are also found on Earth, in car exhaust and on burnt toast, among other places. Here, the molecules are being heated up by the young stars, and, as a result, shine in infrared light. This image was taken by the infrared array camera on Spitzer. It is a 4-color composite of infrared light, showing emissions from wavelengths of 3.6 microns (blue), 4.5 microns (green), 5.8 microns (orange), and 8.0 microns (red). Starlight has been subtracted from the orange and red channels in order to enhance the dust features.

  15. Contemporary Pollution Due Old Uranium Tails

    International Nuclear Information System (INIS)

    Hadjamberdiev, I.

    2007-01-01

    The areas of our study are uranium mining areas (with tails and dumps) Min-Kush, Kadji-Sai, Mailuu-Suu. These areas situated in different parts of Tien-Shan region. We study the content (and correlations among): level of uranium in environment, immune function and level, level in human teeth. It has been found: content of uranium in river water under tails about 2,0x10-5 gm/litter, and high level in drinking water too 2,0-4,0. Drying grass and flowers uranium content was 0,04-0,51x10-5 gm/gm, most high content were in Tacniatherum crinitum and Atgilops triuncialis. Lams tissues contain 0,005-2,44 mg/g in Min-Kush, 0,03-0,107, in Mailuu-Suu, and 0,001-0,048 mg/g in Kadji-Sai. Human teeth uranium content (Mailuu-Suu): in milk-teeth 0,481x10-6 gm/gm, in former miners 0,7684x10-6 gm/gm. Inhabitants of the area, which not working in uranium industry have 0,6876x10-6 gm/gm. There was low level of immune function (lymphocytes, IgI globulin, etc) in all three regions (in child, in adults, in uranium-mining worked people). There is no doubt of the positive correlations of uranium pollution of water (by underground infiltration from tails) on one hand and, on the other hand - a) grass, b) lambs body, c) human teeth, d) human immune function. Levels of uranium in teeth strictly depend on time of mining contact. (author)

  16. Optimization in the decommissioning of uranium tailings

    International Nuclear Information System (INIS)

    1987-06-01

    This report examines in detail the problem of choosing the optimal decommissioning approach for uranium and mill tailings sites. Various decision methods are discussed and evaluated, and their application in similar decision problems are summarized. This report includes, by means of a demonstration, a step by step guide of how a number of selected techniques can be applied to a decommissioning problem. The strengths and weaknesses of various methods are highlighted. A decision system approach is recommended for its flexibility and incorporation of many of the strengths found in other decision methods

  17. Biogeochemistry of metalliferous mine tailings during phytostabilizatio

    Science.gov (United States)

    Chorover, J.; Root, R. A.; Hammond, C.; Wang, Y.; Maier, R. M.

    2015-12-01

    In the semi-arid southwest US, legacy mine tailings and the associated metal(loid) contaminants, are prone to wind dispersion and water erosion. Without remediation, tailings can remain barren for decades to centuries, providing a point source of toxic contamination. Successful mitigation of toxins (As, Pb) from fugitive dust is often limited to confinement and stabilization. Capping mine tailings with soil or gravel is an accepted, although expensive, strategy to reduce erosion. Revegetation via assisted direct planting (also known as phytostabilization) has the potential to be a cost-effective and self-sustaining alternative "green-technology" to expensive capping. The impact of phytostabilization, and requisite added organic carbon and irrigation on mechanisms of contaminant mobility is being investigated with concurrent highly-instrumented greenhouse mesocosms and in situ field studies using advanced microbiological tools and synchrotron x-ray based molecular probes. Composted treatments initially neutralized the near surface acid tailings (~2 to ~6.5). However, after 9 mo the mesocosms showed a gradual and eventual decrease back to pH 2. The exception was the root zone of Atriplex lentiformis, which buffered the acidic conditions for 12 months. Rhizosphere microbiota experienced a 5-log increase in the compost-amended compared to control greenhouse mesocosms. Weathering of the primary sulfidic mineral assemblage, indicated by the iron and sulfur speciation, was shown to control the mobility, speciation and bioavailability of both As and Pb via sequestration in (meta)stable neoformed jarosite phases as plumbojarosite and As(V) substituted for sulfate in hydronium jarosite, with important implications for human and environmental health risk management. We conclude that the disequilibrium imposed by phytostabilization results in an increase of heterotrophic biomass that is concurrent with a time series of geochemical transformations, which controls the species

  18. Reliability of Measuring Lumbar Lordosis, Flexion and Extension Using Dual Inclinometer in Healthy Subjects and Patients with Non-Specific Chronic Low Back Pain

    Directory of Open Access Journals (Sweden)

    Samira Garmabi

    2012-07-01

    Full Text Available Objective: Accurate assessment of lumbar range of motion is of great value for both evaluating lumbar functions and monitoring treatment progress. Recent research indicates that there is no general consensus on the most valid and reliable method of measuring spinal range of motion. The purpose of this study was to determine the intra-rater reliability of lumbar flexion and extension measurements (within-day and between-days using the dual inclinometer technique.   Materials & Methods: Lumbar flexion and extension of 22 women (14 healthy and 8 with low back pain, were measured by the same examiner on three occasions. The first two measurements were taken with half an hour apart on the first occasion to assess the within-day reliability and the third measurement was taken one week later to assess the between-days reliability.  Results: Within-day lumbar lordosis, flexion and extension measurements using dual inclinometer technique were shown to be very reliable with high Intraclass Correlation Coefficients (ICC values (ICC were 98%, 77% and 69% for lordosis, flexion and extension measurements, respectively in healthy subjects and 94%, 95% and 69% for lordosis, flexion and extension measurements, respectively in patients group. Between-Days measurements also demonstrated high reliability with the high values of ICC (ICC were 96%, 70% and 67% for lordosis, flexion and extension measurements, in healthy subjects and 91%, 71% and 66% for lordosis, flexion and extension measurements, respectively in patients group. Conclusion: The results indicated that, the dual inclinometer technique appears to be a highly reliable method for measuring lumbar lordosis, flexion and extension and can be used as a reliable tool in the assessment of lumbar range of motion and monitoring therapeutic interventions.

  19. Tail-weighted dependence measures with limit being the tail dependence coefficient

    KAUST Repository

    Lee, David

    2017-12-02

    For bivariate continuous data, measures of monotonic dependence are based on the rank transformations of the two variables. For bivariate extreme value copulas, there is a family of estimators (Formula presented.), for (Formula presented.), of the extremal coefficient, based on a transform of the absolute difference of the α power of the ranks. In the case of general bivariate copulas, we obtain the probability limit (Formula presented.) of (Formula presented.) as the sample size goes to infinity and show that (i) (Formula presented.) for (Formula presented.) is a measure of central dependence with properties similar to Kendall\\'s tau and Spearman\\'s rank correlation, (ii) (Formula presented.) is a tail-weighted dependence measure for large α, and (iii) the limit as (Formula presented.) is the upper tail dependence coefficient. We obtain asymptotic properties for the rank-based measure (Formula presented.) and estimate tail dependence coefficients through extrapolation on (Formula presented.). A data example illustrates the use of the new dependence measures for tail inference.

  20. Tail-weighted dependence measures with limit being the tail dependence coefficient

    KAUST Repository

    Lee, David; Joe, Harry; Krupskii, Pavel

    2017-01-01

    For bivariate continuous data, measures of monotonic dependence are based on the rank transformations of the two variables. For bivariate extreme value copulas, there is a family of estimators (Formula presented.), for (Formula presented.), of the extremal coefficient, based on a transform of the absolute difference of the α power of the ranks. In the case of general bivariate copulas, we obtain the probability limit (Formula presented.) of (Formula presented.) as the sample size goes to infinity and show that (i) (Formula presented.) for (Formula presented.) is a measure of central dependence with properties similar to Kendall's tau and Spearman's rank correlation, (ii) (Formula presented.) is a tail-weighted dependence measure for large α, and (iii) the limit as (Formula presented.) is the upper tail dependence coefficient. We obtain asymptotic properties for the rank-based measure (Formula presented.) and estimate tail dependence coefficients through extrapolation on (Formula presented.). A data example illustrates the use of the new dependence measures for tail inference.

  1. Distal nerve transfer versus supraclavicular nerve grafting: comparison of elbow flexion outcome in neonatal brachial plexus palsy with C5-C7 involvement.

    Science.gov (United States)

    Heise, Carlos O; Siqueira, Mario G; Martins, Roberto S; Foroni, Luciano H; Sterman-Neto, Hugo

    2017-09-01

    Ulnar and median nerve transfers to arm muscles have been used to recover elbow flexion in infants with neonatal brachial plexus palsy, but there is no direct outcome comparison with the classical supraclavicular nerve grafting approach. We retrospectively analyzed patients with C5-C7 neonatal brachial plexus palsy submitted to nerve surgery and recorded elbow flexion recovery using the active movement scale (0-7) at 12 and 24 months after surgery. We compared 13 patients submitted to supraclavicular nerve grafting with 21 patients submitted to distal ulnar or median nerve transfer to biceps motor branch. We considered elbow flexion scores of 6 or 7 as good results. The mean elbow flexion score and the proportion of good results were better using distal nerve transfers than supraclavicular grafting at 12 months (p nerve grafting at 12 months showed good elbow flexion recovery after ulnar nerve transfers. Distal nerve transfers provided faster elbow flexion recovery than supraclavicular nerve grafting, but there was no significant difference in the outcome after 24 months of surgery. Patients with failed supraclavicular grafting operated early can still benefit from late distal nerve transfers. Supraclavicular nerve grafting should remain as the first line surgical treatment for children with neonatal brachial plexus palsy.

  2. Comparison of knee flexion isokinetic deficits between seated and prone positions after ACL reconstruction with hamstrings graft: Implications for rehabilitation and return to sports decisions.

    Science.gov (United States)

    Koutras, Georgios; Bernard, Manfred; Terzidis, Ioannis P; Papadopoulos, Pericles; Georgoulis, Anastasios; Pappas, Evangelos

    2016-07-01

    Hamstrings grafts are commonly used in ACL reconstruction, however, the effect of graft harvesting on knee flexion strength has not been longitudinally evaluated in functional positions. We hypothesized that greater deficits in knee flexion strength exist in the prone compared to the seated position and these deficits remain as rehabilitation progresses. Case series. Forty-two consecutive patients who underwent ACL reconstruction with a hamstrings graft were followed prospectively for 9 months. Isokinetic knee flexion strength at a slow and a fast speed were collected at 3, 4, 6, and 9 months in two different positions: conventional (seated) and functional (0° of hip flexion). Peak torque knee flexion deficits were higher in the prone position compared to the seated position by an average of 6.5% at 60°/s and 9.1% at 180°/s (p<0.001). Measuring knee flexion strength in prone demonstrates higher deficits than in the conventional seated position. Most athletes would not be cleared to return to sports even at 9 months after surgery with this method. Copyright © 2015 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  3. Tactile cues can change movement: An example using tape to redistribute flexion from the lumbar spine to the hips and knees during lifting.

    Science.gov (United States)

    Pinto, Brendan L; Beaudette, Shawn M; Brown, Stephen H M

    2018-05-14

    Given the appropriate cues, kinematic factors associated with low back injury risk and pain, such as spine flexion, can be avoided. Recent research has demonstrated the potential for tactile sensory information to change movement. In this study an athletic strapping tape was applied bilaterally along the lumbar extensor muscles to provide continuous tactile feedback information during a repeated lifting and lowering task. The presence of the tape resulted in a statistically significant reduction in lumbar spine flexion when compared to a baseline condition in which no tape was present. This reduction was further increased with the explicit instruction to pay attention to the sensations elicited by the tape. In both cases, the reduction in lumbar spine flexion was compensated for by increases in hip and knee flexion. When the tape was then removed and participants were instructed to continue lifting as if it was still present, the reduction in lumbar flexion and increases in hip and knee flexion were retained. Thus this study provides evidence that tactile cues can provide vital feedback information that can cue human lumbar spine movement to reduce kinematic factors associated with injury risk and pain. Copyright © 2018 Elsevier B.V. All rights reserved.

  4. Recent advancements in the geotechnical characterization of oil sands tailings

    Energy Technology Data Exchange (ETDEWEB)

    Sharp, J. [Conetec, Richmond, BC (Canada)

    2010-07-01

    The technical aspects of soft oil sands tailings in-situ geotechnical site investigations were discussed. Geotechnical studies are conducted to determine containment structure stability as well as to determine volumetric and mass balances. The results of the studies are used in tailings management plans and construction activities. Flow penetrometers, field vane shear tests, and Gamma-CPTu tests are used in in-situ oil sands tailings geotechnical studies in order to determine pore pressure dissipation, and measure shear strength. Ball penetration tests are conducted to determine tailings strength. Methods of interpreting data from the tests were presented, and data from the tests were also compared and evaluated. Recommended procedures for strength screening were presented. Statistical methods for determining tailings behaviour types were outlined. The study showed that Gamma-CPTu data can be used to obtain reasonable preliminary estimates of solids and fines when combined with tailings behaviour type analyses. tabs., figs.

  5. Utilization of mine tailings as partial cement replacement

    DEFF Research Database (Denmark)

    Sigvardsen, Nina Marie; Nielsen, M.R.; Ottosen, Lisbeth M.

    2017-01-01

    Depositing mine tailings entail major economic costs and negative environmental impacts. Thus finding an alternative to depositing is of interest. This study focused on the use of mine tailings as partial cement replacement, thereby preventing depositing the mine tailings. At the same time......, such use would reduce the CO2 emission related to the production of cement. Mine tailings from two different mines Zinkgruvan (Sweden) and Nalunaq (Greenland) were both tested as 5 and 10 % cement replacement. All mortar specimens with mine tailings had lower compressive strength compared to a reference...... compared to a specimen containing a 10 % replacement of cement with coal fly ash, commonly used in Denmark. The compressive strength of specimens containing mine tailings exceeded the compressive strength of the specimen containing coal fly ash, indicating further the amorphous content of volcanic decent...

  6. Solar wind interaction with type-1 comet tails

    International Nuclear Information System (INIS)

    Ershkovich, A.I.

    1977-01-01

    A comet tail is considered as a plasma cylinder separated by a tangential discontinuity surface from the solar wind. Under typical conditions a comet tail boundary is shown to undergo the Kelvin-Helmholtz instability. With infinite amplitude the stabilizing effect of the magnetic field increases, and waves become stable. The proposed model supplies the detailed quantitative description of helical waves observed in type-1 comet tails. This theory enables the evaluation of the comet tail magnetic field by means of the observations of helical waves. The magnetic field in the comet tail turns out to be of the order of the interplanetary field. This conclusion seems to be in accordance with Alfven's idea that the magnetic field in type-1 comet tails is a captured interplanetary field. (Auth.)

  7. Flotation tailings as a raw material for ceramic building materials

    Energy Technology Data Exchange (ETDEWEB)

    Burmistrov, V N; Karpunina, T I; Smolin, V N

    1986-02-01

    The VNIIstrom research institute developed a method for utilizing flotation tailings for production of bricks. Tailings are dewatered using filter presses. After dewatering, moisture content in the tailings ranges from 25 to 26%. Tailings are mixed with chamotte with a grain size to 2 mm. Using 30% chamotte improves mechanical and physical properties of the bricks and reduces energy consumption of brick firing. Tailings mixed with chamotte are granulated and dried on a conveyor. Granules with moisture content reduced to the optimum level are mixed a second time and formed in a press. The bricks are fired in a tunnel kiln with modified design. The bricks made of flotation tailings mixed with 30% chamotte are characterized by mechanical properties comparable to those of high quality bricks made of conventional materials.

  8. Naphtha evaporation from oil sands tailings ponds

    Energy Technology Data Exchange (ETDEWEB)

    Kasperski, K.; Munoz, V.; Mikula, R. [Natural Resources Canada, Devon, AB (Canada). CANMET Western Research Centre

    2010-07-01

    The environmental impacts of volatile organic compounds (VOCs) from oil sands tailings ponds must be considered when evaluating new oil sands mining and extraction operations. Studies have suggested that only 40 percent of the solvent sent to tailings ponds is available to the environment, while the rest is irreversibly trapped. The recovery of hydrocarbons from oil sands froth process water is low. This PowerPoint presentation discussed a method of distinguishing between water and hydrocarbons at low temperatures. Samples were heated to 246 degrees C at 15 degrees C and held for 10 minutes. Heating was then resumed at 750 degrees C and held for 10 minutes in a pyrolysis phase, then cooled and reheated with an oxygen addition. The method demonstrated that the diluent distribution between the solids and water phases is misinterpreted as diluent that will evaporate, and diluent that will not evaporate. The study concluded by suggesting that the definition of recoverable and unrecoverable hydrocarbon should be re-termed as easily recoverable, and difficult to recover. tabs., figs.

  9. Efficient bootstrap estimates for tail statistics

    Science.gov (United States)

    Breivik, Øyvind; Aarnes, Ole Johan

    2017-03-01

    Bootstrap resamples can be used to investigate the tail of empirical distributions as well as return value estimates from the extremal behaviour of the sample. Specifically, the confidence intervals on return value estimates or bounds on in-sample tail statistics can be obtained using bootstrap techniques. However, non-parametric bootstrapping from the entire sample is expensive. It is shown here that it suffices to bootstrap from a small subset consisting of the highest entries in the sequence to make estimates that are essentially identical to bootstraps from the entire sample. Similarly, bootstrap estimates of confidence intervals of threshold return estimates are found to be well approximated by using a subset consisting of the highest entries. This has practical consequences in fields such as meteorology, oceanography and hydrology where return values are calculated from very large gridded model integrations spanning decades at high temporal resolution or from large ensembles of independent and identically distributed model fields. In such cases the computational savings are substantial.

  10. Environmental impact analysis of mine tailing reservoir

    Science.gov (United States)

    Gong, J. Z.

    2016-08-01

    Under certain conditions landscape topography which utilizes mine tailing reservoir construction using is likely to increase lateral recharge source regions, resulting in dramatic changes to the local hydrological dynamic field and recharge of downstream areas initiated by runoff, excretion state, elevated groundwater depth, shallow groundwater, rainfall direct communication, and thinning of the vadose zone. Corrosive leaching of topsoil over many years of exposure to chemical fertilizers and pesticides may result in their dissolution into the groundwater system, which may lead to excessive amounts of many harmful chemicals, therby affecting the physical and mental health of human residents and increase environmental vulnerability and risk associated with the water and soil. According to field survey data from Yujiakan, Qian'an City, and Hebei provinces, this paper analyzes the hydrogeological environmental mechanisms of areas adjacent to mine tailing reservoirs and establishes a conceptual model of the local groundwater system and the concentration-response function between NO3 - content in groundwater and the incidence of cancer in local residents.

  11. Submarine Tailings Disposal (STD—A Review

    Directory of Open Access Journals (Sweden)

    Bernhard Dold

    2014-07-01

    Full Text Available The mining industry is a fundamental industry involved in the development of modern society, but is also the world’s largest waste producer. This role will be enhanced in the future, because ore grades are generally decreasing, thus leading to increases in the waste/metal production ratio. Mine wastes deposited on-land in so-called tailings dams, impoundments or waste-dumps have several associated environmental issues that need to be addressed (e.g., acid mine drainage formation due to sulphide oxidation, geotechnical stability, among others, and social concerns due to land use during mining. The mining industry recognizes these concerns and is searching for waste management alternatives for the future. One option used in the past was the marine shore or shallow submarine deposition of this waste material in some parts of the world. After the occurrence of some severe environmental pollution, today the deposition in the deep sea (under constant reducing conditions is seen as a new, more secure option, due to the general thought that sulphide minerals are geochemically stable under the reduced conditions prevailing in the deep marine environment. This review highlights the mineralogical and geochemical issues (e.g., solubility of sulphides in seawater; reductive dissolution of oxide minerals under reducing conditions, which have to be considered when evaluating whether submarine tailings disposal is a suitable alternative for mine waste.

  12. Oil sands tailings leachability and toxicity evaluation

    International Nuclear Information System (INIS)

    Gulley, J.R.

    1995-01-01

    Fine tailings disposal and reclamation is a major issue facing the oil sands mining and extraction industry. Government regulations dictate that reclamation must return the site to a level of self-sustaining biological capability which approximates the natural condition. A two-phase laboratory program has been completed to investigate the suitability of alternative reclamation materials. For the first phase of the study, chemical and toxicological analyses were carried out on 13 different reclamation and reference materials (solid phase and extractions). Seedling emergence, nematode maturation, algal growth and bacterial luminescence for leachate samples showed a range of sensitivities in response to the tested materials, although phytotoxicity tests were generally the most sensitive. With the exception of one test material, high toxicity ratings were consistent with that expected from the chemical data. The second phase of the study focused on the evaluation of chemical and toxicological conditions in leachate water generated using bench-scale column percolation tests. Leachate water equivalent to 10 pore volume replacements was generated and temporal variations in toxicity and chemistry monitored. Similar to phase 1 findings, phytotoxicity tests were the most sensitive tests to leachate waters. For most materials tested, most toxicity was removed after 2--3 porewater replacements. More persistent toxicity was noted for samples containing bitumen (e.g., fine tails and oil sands). No clear correspondence was noted between chemical concentrations and toxicity in leachate waters

  13. Sulfur biogeochemistry of oil sands composite tailings

    Energy Technology Data Exchange (ETDEWEB)

    Warren, Lesley; Stephenson, Kate [Earth Sciences, McMaster University (Canada)], email: warrenl@mcmaster.ca; Penner, Tara [Syncrude Environmental Research (Canada)

    2011-07-01

    This paper discusses the sulfur biogeochemistry of oil sands composite tailings (CT). The Government of Alberta is accelerating reclamation activities on composite tailings. As a CT pilot reclamation operation, Syncrude is currently constructing the first freshwater fen. Minor unpredicted incidents with H2S gas released from the dewatering process associated with these reclamations have been reported. The objective of this study is to ascertain the connection between microbial activity and H2S generation within CT and to assess the sulfur biogeochemistry of untreated and treated (fen) CT over seasonal and annual timescales. The microbial geochemical interactions taking place are shown using a flow chart. CT is composed of gypsum, sand, clay and organics like naphthenic acids and bitumen. Sulfur and Fe cycling in mining systems and their microbial activities are presented. The chemistry and the processes involved within CT are also given along with the results. It can be said that the diverse Fe and S metabolizing microorganisms confirm the ecology involved in H2S dynamics.

  14. Uranium mill tailings backfill management. Final report

    International Nuclear Information System (INIS)

    Thomson, B.M.; Heggen, R.J.

    1984-01-01

    Backfilling, the disposal of spent uranium mill tailings in empty mine stopes, has been practiced in the Grants Mineral Belt of New Mexico for nearly 20 years. The principal objective of backfilling is the prevention of roof collapse and hydraulic connection with overlying aquifers, increasing mine dewatering requirements. Backfilling is accomplished by gravity feed of a slurry of sand-fraction tailings and treated mine water into the slope. The effects of backfilling on surface discharge of mine wastewater are negligible due to the small fraction of the total flow represented by slurry decant. Furthermore, quality of the decant is not significantly below that of other mine waters. Groundwater effects of backfilling may be classified as short-term (while the mine is operational) and long-term (after dewatering operations have been terminated). Short-term effects are insignificant because of rapid and continuous flow to the mine sump. Long-term effects on aquifer water quality are predicted to be minimal due to (1) the small amount of slurry liquor present after drainage, (2) the precipitation of SO 4 and CO 3 phases, and (3) the reestablishment of reducing conditions and subsequent precipitation of major contaminants including U, As, Mo, Se, and V. 28 references, 19 figures, 9 tables

  15. The big head and the long tail

    DEFF Research Database (Denmark)

    Helles, Rasmus

    2013-01-01

    This paper discusses how the advent of big data challenges established theories in Internet studies to redevelop existing explanatory strategies in order to incorporate the possibilities offered by this new empirical resource. The article suggests that established analytical procedures and theore......This paper discusses how the advent of big data challenges established theories in Internet studies to redevelop existing explanatory strategies in order to incorporate the possibilities offered by this new empirical resource. The article suggests that established analytical procedures...... and theoretical frameworks used in Internet studies can be fruitfully employed to explain high–level structural phenomena that are only observable through the use of big data. The present article exemplifies this by offering a detailed analysis of how genre analysis of Web sites may be used to shed light...... on the generative mechanism behind the long–tail distribution of Web site use. The analysis shows that the long tail should be seen as a tiered version of popular top sites, and argues that downsizing of large–scale datasets in combination with qualitative and/or small–scale quantitative procedures may provide...

  16. Transverse tails and higher order moments

    International Nuclear Information System (INIS)

    Spence, W.L.; Decker, F.J.; Woodley, M.D.

    1993-05-01

    The tails that may be engendered in a beam's transverse phase space distribution by, e.g., intrabunch wakefields and nonlinear magnetic fields, are all important diagnostic and object of tuning in linear colliders. Wire scanners or phosphorescent screen monitors yield one dimensional projected spatial profiles of such beams that are generically asymmetric around their centroids, and therefore require characterization by the third moment left-angle x 3 right-angle in addition to the conventional mean-square or second moment. A set of measurements spread over sufficient phase advance then allows the complete set left-angle x 3 right-angle, left-angle xx' 2 right-angle, left-angle x' 3 right-angle, and left-angle x 2 x'right-angle to be deduced -- the natural extension of the well-known ''emittance measurement'' treatment of second moments. The four third moments may be usefully decomposed into parts rotating in phase space at the β-tron frequency and at its third harmonic, each specified by a phase-advance-invariant amplitude and a phase. They provide a framework for the analysis and tuning of transverse wakefield tails

  17. Manual for the sampling of uranium mine tailings

    International Nuclear Information System (INIS)

    Feenstra, S.; Reades, D.W.; Cherry, J.A.; Chambers, D.B.; Case, G.G.; Ibbotson, B.G.

    1983-04-01

    The purpose of this manual is to describe the requisite sampling procedures to provide a basis for the application of uniform high-quality standards to detailed geotechnical, hydrogeological, geochemical and air quality measurements at Canadian uranium tailings disposal sites. The report describes the objective and scope of a sampling program, the preliminary data collection, and the procedures for sampling of tailings solids, surface water and seepage, tailings porewater, and wind-blown dust and radon

  18. Bacterial reduction of selenium in coal mine tailings pond sediment

    Energy Technology Data Exchange (ETDEWEB)

    Siddique, T.; Arocena, J.M.; Thring, R.W.; Zhang, Y.Q. [University of North British Columbia, Prince George, BC (Canada)

    2007-05-15

    Sediment from a storage facility for coal tailings solids was assessed for its capacity to reduce selenium (Se) by native bacterial community. One Se{sup 6+}-reducing bacterium Enterobacter hormaechei (Tar11) and four Se{sup 4+}-reducing bacteria, Klebsiella pneumoniae (Tar1), Pseudomonasfluorescens (Tar3), Stenotrophomonas maltophilia (Tar6), and Enterobacter amnigenus (Tar8) were isolated from the sediment. Enterobacter horinaechei removed 96% of the added Se{sup 6+} (0.92 mg L{sup -1} from the effluents when Se6+ was determined after 5 d of incubation. Analysis of the red precipitates showed that Se{sup 6+} reduction resulted in the formation of spherical particles ({lt}1.0 {mu} m) of Se 0 as observed under scanning electron microscope (SEM) and confirmed by EDAX. Selenium speciation was performed to examine the fate of the added Se{sup 6+} in the sediment with or without addition of Enterobacter hormaechei cells. More than 99% of the added Se{sup 6+} (about 2.5 mg L{sup -1}) was transformed in the nonsterilized sediment (without Enterobacter hormaechei cells) as well as in the sterilized (heat-killed) sediment (with Enterobacter hormaechei cells). The results of this study suggest that the lagoon sediments at the mine site harbor Se{sup 6+}- and Se{sup 4+} -reducing bacteria and may be important sinks for soluble Se (Se{sup 6+} and Se{sup 4+}). Enterobacter hormaechei isolated from metal-contaminated sediment may have potential application in removing Se from industrial effluents.

  19. Reclamation of copper mine tailings using sewage sludge

    OpenAIRE

    Stjernman Forsberg, Lovisa

    2008-01-01

    Tailings are the fine-grained fraction of waste produced during mining operations. This work was carried out on tailings from the Aitik copper mine in northern Sweden. Establishment of vegetation on the Aitik mine tailings deposit is planned to take place at closure of the mine, using sewage sludge as fertiliser. However, the tailings contain traces of metal sulphides, e.g. pyrite, FeS2, and chalcopyrite, CuFeS2. When the sulphides are oxidised, they start to weather and release metals and st...

  20. Ecological restoration alters microbial communities in mine tailings profiles.

    Science.gov (United States)

    Li, Yang; Jia, Zhongjun; Sun, Qingye; Zhan, Jing; Yang, Yang; Wang, Dan

    2016-04-29

    Ecological restoration of mine tailings have impact on soil physiochemical properties and microbial communities. The surface soil has been a primary concern in the past decades, however it remains poorly understood about the adaptive response of microbial communities along the profile during ecological restoration of the tailings. In this study, microbial communities along a 60-cm profile were investigated in a mine tailing pond during ecological restoration of the bare waste tailings (BW) with two vegetated soils of Imperata cylindrica (IC) and Chrysopogon zizanioides (CZ) plants. Revegetation of both IC and CZ could retard soil degradation of mine tailing by stimulation of soil pH at 0-30 cm soils and altered the bacterial communities at 0-20 cm depths of the mine tailings. Significant differences existed in the relative abundance of the phyla Alphaproteobacteria, Deltaproteobacteria, Acidobacteria, Firmicutes and Nitrospira. Slight difference of bacterial communities were found at 30-60 cm depths of mine tailings. Abundance and activity analysis of nifH genes also explained the elevated soil nitrogen contents at the surface 0-20 cm of the vegetated soils. These results suggest that microbial succession occurred primarily at surface tailings and vegetation of pioneering plants might have promoted ecological restoration of mine tailings.

  1. (measured as NDVI) over mine tailings at Mhangura Copper Mine

    African Journals Online (AJOL)

    chari

    Remote sensing techniques are increasingly being employed in monitoring environmental ... normalised difference vegetation index (NDVI), remote sensing, tailings ..... rehabilitation monitoring by adding landscape function characteristics.

  2. Review of fugitive dust control for uranium mill tailings

    International Nuclear Information System (INIS)

    Li, C.T.; Elmore, M.R.; Hartley, J.N.

    1983-01-01

    An immediate concern associated with the disposal of uranium mill tailings is that wind erosion of the tailings from an impoundment area will subsequently deposit tailings on surrounding areas. Pacific Northwest Laboratory (PNL), under contract to the U.S. Nuclear Regulatory Commission, is investigating the current technology for fugitive dust control. Different methods of fugitive dust control, including chemical, physical, and vegetative, have been used or tested on mill tailings piles. This report presents the results of a literature review and discussions with manufacturers and users of available stabilization materials and techniques

  3. A tale of two tails: Not just skin deep

    Directory of Open Access Journals (Sweden)

    Abhijit Dutta

    2015-01-01

    Full Text Available The dorsal cutaneous appendage or the so called human tail is a rare congenital anomaly protruding from the lumbo-sacro-coccygeal area. These caudal appendages are divided into true-tails and pseudo-tails. We report here two cases of congenital pseudo-tail with underlying spina bifida and lipo-meningocele. In this article we seek to emphasize that, as the skin and nervous systems are intimately linked by their similar ectodermal origin, a dorsal appendage may be regarded as a cutaneous marker of the underlying spinal dysraphism.

  4. Top Incomes, Heavy Tails, and Rank-Size Regressions

    Directory of Open Access Journals (Sweden)

    Christian Schluter

    2018-03-01

    Full Text Available In economics, rank-size regressions provide popular estimators of tail exponents of heavy-tailed distributions. We discuss the properties of this approach when the tail of the distribution is regularly varying rather than strictly Pareto. The estimator then over-estimates the true value in the leading parametric income models (so the upper income tail is less heavy than estimated, which leads to test size distortions and undermines inference. For practical work, we propose a sensitivity analysis based on regression diagnostics in order to assess the likely impact of the distortion. The methods are illustrated using data on top incomes in the UK.

  5. Ecological restoration alters microbial communities in mine tailings profiles

    Science.gov (United States)

    Li, Yang; Jia, Zhongjun; Sun, Qingye; Zhan, Jing; Yang, Yang; Wang, Dan

    2016-04-01

    Ecological restoration of mine tailings have impact on soil physiochemical properties and microbial communities. The surface soil has been a primary concern in the past decades, however it remains poorly understood about the adaptive response of microbial communities along the profile during ecological restoration of the tailings. In this study, microbial communities along a 60-cm profile were investigated in a mine tailing pond during ecological restoration of the bare waste tailings (BW) with two vegetated soils of Imperata cylindrica (IC) and Chrysopogon zizanioides (CZ) plants. Revegetation of both IC and CZ could retard soil degradation of mine tailing by stimulation of soil pH at 0-30 cm soils and altered the bacterial communities at 0-20 cm depths of the mine tailings. Significant differences existed in the relative abundance of the phyla Alphaproteobacteria, Deltaproteobacteria, Acidobacteria, Firmicutes and Nitrospira. Slight difference of bacterial communities were found at 30-60 cm depths of mine tailings. Abundance and activity analysis of nifH genes also explained the elevated soil nitrogen contents at the surface 0-20 cm of the vegetated soils. These results suggest that microbial succession occurred primarily at surface tailings and vegetation of pioneering plants might have promoted ecological restoration of mine tailings.

  6. Review of fugitive dust control for uranium mill tailings

    Energy Technology Data Exchange (ETDEWEB)

    Li, C.T.; Elmore, M.R.; Hartley, J.N.

    1983-01-01

    An immediate concern associated with the disposal of uranium mill tailings is that wind erosion of the tailings from an impoundment area will subsequently deposit tailings on surrounding areas. Pacific Northwest Laboratory (PNL), under contract to the U.S. Nuclear Regulatory Commission, is investigating the current technology for fugitive dust control. Different methods of fugitive dust control, including chemical, physical, and vegetative, have been used or tested on mill tailings piles. This report presents the results of a literature review and discussions with manufacturers and users of available stabilization materials and techniques.

  7. Modelling of contaminant release from a uranium mine tailings site

    International Nuclear Information System (INIS)

    Kahnt, Rene; Metschies, Thomas

    2007-01-01

    Available in abstract form only. Full text of publication follows: Uranium mining and milling continuing from the early 1960's until 1990 close to the town of Seelingstaedt in Eastern Germany resulted in 4 tailings impoundments with a total tailings volume of about 105 Mio. m 3 . Leakage from these tailings impoundments enters the underlying aquifers and is discharged into surface water streams. High concentration of salts, uranium and several heavy metals are released from the tailings. At present the tailings impoundments are reshaped and covered. For the identification of suitable remediation options predictions of the contaminant release for different remediation scenarios have to be made. A compartment model representing the tailings impoundments and the surrounding aquifers for the calculation of contaminant release and transport was set up using the software GOLDSIM. This compartment model describes the time dependent hydraulic conditions within the tailings and the surrounding aquifers taking into account hydraulic and geotechnical processes influencing the hydraulic properties of the tailings material. A simple geochemical approach taking into account sorption processes as well as retardation by applying a k d -approach was implemented to describe the contaminant release and transport within the hydraulic system. For uranium as the relevant contaminant the simple approach takes into account additional geochemical conditions influencing the mobility. Alternatively the model approach allows to include the results of detailed geochemical modelling of the individual tailings zones which is than used as source term for the modelling of the contaminant transport in the aquifer and to the receiving streams. (authors)

  8. Estimating impact forces of tail club strikes by ankylosaurid dinosaurs.

    Directory of Open Access Journals (Sweden)

    Victoria Megan Arbour

    Full Text Available BACKGROUND: It has been assumed that the unusual tail club of ankylosaurid dinosaurs was used actively as a weapon, but the biological feasibility of this behaviour has not been examined in detail. Ankylosaurid tail clubs are composed of interlocking vertebrae, which form the handle, and large terminal osteoderms, which form the knob. METHODOLOGY/PRINCIPAL FINDINGS: Computed tomographic (CT scans of several ankylosaurid tail clubs referred to Dyoplosaurus and Euoplocephalus, combined with measurements of free caudal vertebrae, provide information used to estimate the impact force of tail clubs of various sizes. Ankylosaurid tails are modeled as a series of segments for which mass, muscle cross-sectional area, torque, and angular acceleration are calculated. Free caudal vertebrae segments had limited vertical flexibility, but the tail could have swung through approximately 100 degrees laterally. Muscle scars on the pelvis record the presence of a large M. longissimus caudae, and ossified tendons alongside the handle represent M. spinalis. CT scans showed that knob osteoderms were predominantly cancellous, which would have lowered the rotational inertia of the tail club and made it easier to wield as a weapon. CONCLUSIONS/SIGNIFICANCE: Large knobs could generate sufficient force to break bone during impacts, but average and small knobs could not. Tail swinging behaviour is feasible in ankylosaurids, but it remains unknown whether the tail was used for interspecific defense, intraspecific combat, or both.

  9. Proceedings of the 15. annual British Columbia MEND ML/ARD workshop : the management of tailings and tailings impoundments

    International Nuclear Information System (INIS)

    2009-02-01

    This Mine Environment Neutral Drainage (MEND) workshop was held to promote the exchange of information and ideas on environmental protection and reclamation associated with mining. The workshop covered a broad spectrum of reclamation issues and the key environmental challenges facing the mining industry, such as acid mine drainage (AMD) control, and metal leaching and acid rock drainage (ML/ARD). The theme for the 2008 workshop was the management of tailings and tailings impoundments. Topics of discussion included hydrogeology and geochemistry; tailings disposal; mitigation; closure plans; and postclosure performance. The emphasis was on full-scale case studies, practical constraints and sustaining successful disposal strategies and remediation. The session on tailings management reviewed overarching policies and practices; methods of subaerial tailings disposal and case studies of tailings management; and detailed investigations of geochemical properties and processes. The conference featured 22 presentations, of which 4 have been catalogued separately for inclusion in this database. refs., tabs., figs

  10. The bending stiffness of shoes is beneficial to running energetics if it does not disturb the natural MTP joint flexion.

    Science.gov (United States)

    Oh, Keonyoung; Park, Sukyung

    2017-02-28

    A local minimum for running energetics has been reported for a specific bending stiffness, implying that shoe stiffness assists in running propulsion. However, the determinant of the metabolic optimum remains unknown. Highly stiff shoes significantly increase the moment arm of the ground reaction force (GRF) and reduce the leverage effect of joint torque at ground push-off. Inspired by previous findings, we hypothesized that the restriction of the natural metatarsophalangeal (MTP) flexion caused by stiffened shoes and the corresponding joint torque changes may reduce the benefit of shoe bending stiffness to running energetics. We proposed the critical stiffness, k cr , which is defined as the ratio of the MTP joint (MTPJ) torque to the maximal MTPJ flexion angle, as a possible threshold of the elastic benefit of shoe stiffness. 19 subjects participated in a running test while wearing insoles with five different bending stiffness levels. Joint angles, GRFs, and metabolic costs were measured and analyzed as functions of the shoe stiffness. No significant changes were found in the take-off velocity of the center of mass (CoM), but the horizontal ground push-offs were significantly reduced at different shoe stiffness levels, indicating that complementary changes in the lower-limb joint torques were introduced to maintain steady running. Slight increases in the ankle, knee, and hip joint angular impulses were observed at stiffness levels exceeding the critical stiffness, whereas the angular impulse at the MTPJ was significantly reduced. These results indicate that the shoe bending stiffness is beneficial to running energetics if it does not disturb the natural MTPJ flexion. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. CT imaging techniques for describing motions of the cervicothoracic junction and cervical spine during flexion, extension, and cervical traction.

    Science.gov (United States)

    Simon, Scott; Davis, Martin; Odhner, Dewey; Udupa, Jayaram; Winkelstein, Beth

    2006-01-01

    Computerized tomographic study of human cadavers undergoing traction and flexion-extension bending. To investigate the feasibility of using computerized tomography techniques to quantify relative vertebral motions of the cervical spine and cervicothoracic junction (CTJ), and to define normative CTJ kinematics. Despite developing an understanding of the mechanical behavior of the cervical spine, little remains known about the cervicothoracic junction. The CTJ is more difficult to image than other cervical regions given the anatomic features of the surrounding bones obstructing CTJ visualization. As such, limited data have been reported describing the responses of the CTJ for motions and loading in the sagittal plane, confounding the clinical assessment of its injuries and surgical treatments used at this region. Helical CT images of the cervical spine and CTJ were acquired incrementally during each of flexion, extension, and cervical traction. Vertebral surfaces were reconstructed using the specialized image analysis software, 3DVIEWNIX. A mathematical description of relative vertebral motions was derived by computing rigid transformations. Euler angles and translations were calculated. Regional spine stiffness was defined for traction. The CTJ was found to be much stiffer (779 N/mm) than the cervical spine (317 N/mm) in tension. In flexion-extension bending, the CTJ was similar to the lower cervical spine. The CTJ demonstrated significantly less coupled motion than the cervical spine. The CTJ, as a transition region between the cervical and thoracic spines, has unique kinematic characteristics. This application of kinematic CT methods is useful for quantifying unreported normative ranges of motion for the CTJ, difficult by other conventional radiologic means.

  12. Chaperone role for proteins p618 and p892 in the extracellular tail development of Acidianus two-tailed virus

    DEFF Research Database (Denmark)

    Scheele, Urte; Erdmann, Susanne; Ungewickell, Ernst J.

    2011-01-01

    The crenarchaeal Acidianus two-tailed virus (ATV) undergoes a remarkable morphological development, extracellularly and independently of host cells, by growing long tails at each end of a spindle-shaped virus particle. Initial work suggested that an intermediate filament-like protein, p800...... the interactions observed between the different protein and DNA components and to explain their possible structural and functional roles in extracellular tail development....

  13. Effects of Tail Clipping on Larval Performance and Tail Regeneration Rates in the Near Eastern Fire Salamander, Salamandra infraimmaculata.

    Directory of Open Access Journals (Sweden)

    Ori Segev

    Full Text Available Tail-tip clipping is a common technique for collecting tissue samples from amphibian larvae and adults. Surprisingly, studies of this invasive sampling procedure or of natural tail clipping--i.e., bites inflicted by predators including conspecifics--on the performance and fitness of aquatic larval stages of urodeles are scarce. We conducted two studies in which we assessed the effects of posterior tail clipping (~30 percent of tail on Near Eastern fire salamander (Salamandra infraimmaculata larvae. In a laboratory study, we checked regeneration rates of posterior tail-tip clipping at different ages. Regeneration rates were hump-shaped, peaking at the age of ~30 days and then decreasing. This variation in tail regeneration rates suggests tradeoffs in resource allocation between regeneration and somatic growth during early and advanced development. In an outdoor artificial pond experiment, under constant larval densities, we assessed how tail clipping of newborn larvae affects survival to, time to, and size at metamorphosis. Repeated measures ANOVA on mean larval survival per pond revealed no effect of tail clipping. Tail clipping had correspondingly no effect on larval growth and development expressed in size (mass and snout-vent length at, and time to, metamorphosis. We conclude that despite the given variation in tail regeneration rates throughout larval ontogeny, clipping of 30% percent of the posterior tail area seems to have no adverse effects on larval fitness and survival. We suggest that future use of this imperative tool for the study of amphibian should take into account larval developmental stage during the time of application and not just the relative size of the clipped tail sample.

  14. Effects of knee extension constraint training on knee flexion angle and peak impact ground-reaction force.

    Science.gov (United States)

    Liu, Hui; Wu, Will; Yao, Wanxiang; Spang, Jeffrey T; Creighton, R Alexander; Garrett, William E; Yu, Bing

    2014-04-01

    Low compliance with training programs is likely to be one of the major reasons for inconsistency of the data regarding the effectiveness of current anterior cruciate ligament (ACL) injury prevention programs. Training methods that reduce training time and cost could favorably influence the effectiveness of ACL injury prevention programs. A newly designed knee extension constraint training device may serve this purpose. (1) Knee extension constraint training for 4 weeks would significantly increase the knee flexion angle at the time of peak impact posterior ground-reaction force and decrease peak impact ground-reaction forces during landing of a stop-jump task and a side-cutting task, and (2) the training effects would be retained 4 weeks after completion of the training program. Controlled laboratory study. Twenty-four recreational athletes were randomly assigned to group A or B. Participants in group A played sports without wearing a knee extension constraint device for 4 weeks and then played sports while wearing the device for 4 weeks, while participants in group B underwent a reversed protocol. Both groups were tested at the beginning of week 1 and at the ends of weeks 4 and 8 without wearing the device. Knee joint angles were obtained from 3-dimensional videographic data, while ground-reaction forces were measured simultaneously using force plates. Analyses of variance were performed to determine the training effects and the retention of training effects. Participants in group A significantly increased knee flexion angles and decreased ground-reaction forces at the end of week 8 (P ≤ .012). Participants in group B significantly increased knee flexion angles and decreased ground-reaction forces at the ends of weeks 4 and 8 (P ≤ .007). However, participants in group B decreased knee flexion angles and increased ground-reaction forces at the end of week 8 in comparison with the end of week 4 (P ≤ .009). Knee extension constraint training for 4 weeks

  15. Comparative study of phrenic nerve transfers with and without nerve graft for elbow flexion after global brachial plexus injury.

    Science.gov (United States)

    Liu, Yuzhou; Lao, Jie; Gao, Kaiming; Gu, Yudong; Zhao, Xin

    2014-01-01

    Nerve transfer is a valuable surgical technique in peripheral nerve reconstruction, especially in brachial plexus injuries. Phrenic nerve transfer for elbow flexion was proved to be one of the optimal procedures in the treatment of brachial plexus injuries in the study of Gu et al. The aim of this study was to compare phrenic nerve transfers with and without nerve graft for elbow flexion after brachial plexus injury. A retrospective review of 33 patients treated with phrenic nerve transfer for elbow flexion in posttraumatic global root avulsion brachial plexus injury was carried out. All the 33 patients were confirmed to have global root avulsion brachial plexus injury by preoperative and intraoperative electromyography (EMG), physical examination and especially by intraoperative exploration. There were two types of phrenic nerve transfers: type1 - the phrenic nerve to anterolateral bundle of anterior division of upper trunk (14 patients); type 2 - the phrenic nerve via nerve graft to anterolateral bundle of musculocutaneous nerve (19 patients). Motor function and EMG evaluation were performed at least 3 years after surgery. The efficiency of motor function in type 1 was 86%, while it was 84% in type 2. The two groups were not statistically different in terms of Medical Research Council (MRC) grade (p=1.000) and EMG results (p=1.000). There were seven patients with more than 4 month's delay of surgery, among whom only three patients regained biceps power to M3 strength or above (43%). A total of 26 patients had reconstruction done within 4 months, among whom 25 patients recovered to M3 strength or above (96%). There was a statistically significant difference of motor function between the delay of surgery within 4 months and more than 4 months (p=0.008). Phrenic nerve transfers with and without nerve graft for elbow flexion after brachial plexus injury had no significant difference for biceps reinnervation according to MRC grading and EMG. A delay of the surgery

  16. Vicious Cycle of Multiple Invasive Treatments in a Hemophilic Inhibitor Positive Child with Resistant Knee Flexion Contracture, A Case Report

    Directory of Open Access Journals (Sweden)

    Amir Reza Kachooei

    2013-12-01

    Full Text Available   Uncontrolled recurrent hemarthrosis can end to contracture, deformity, pain, joint destruction and gait disorders which are disabling. We are going to report a challenge, a unilateral knee flexion contracture in a child with severe hemophilia A and inhibitor who underwent different treatment options with unsatisfactory improvement of knee range of motion. Mismanaging postoperatively, patient and parents irresponsibility in managing self-care, lack of access and affordability to treatment and unavailability of proper treatment can be the reasons of recurrence in addition to the tough nature of a patient with inhibitor.  

  17. Vicious Cycle of Multiple Invasive Treatments in a Hemophilic Inhibitor Positive Child with Resistant Knee Flexion Contracture, A Case Report

    Directory of Open Access Journals (Sweden)

    Amir Reza Kachooei

    2013-12-01

    Full Text Available Uncontrolled recurrent hemarthrosis can end to contracture, deformity, pain, joint destruction and gait disorders which are disabling. We are going to report a challenge, a unilateral knee flexion contracture in a child with severe hemophilia A and inhibitor who underwent different treatment options with unsatisfactory improvement of knee range of motion. Mismanaging postoperatively, patient and parents irresponsibility in managing self-care, lack of access and affordability to treatment and unavailability of proper treatment can be the reasons of recurrence in addition to the tough nature of a patient with inhibitor.

  18. THE NARROW X-RAY TAIL AND DOUBLE Hα TAILS OF ESO 137-002 IN A3627

    International Nuclear Information System (INIS)

    Zhang, B.; Lin, X. B.; Kong, X.; Sun, M.; Ji, L.; Sarazin, C.; Nulsen, P. E. J.; Forman, W.; Jones, C.; Roediger, E.; Donahue, M.; Voit, G. M.

    2013-01-01

    We present the analysis of a deep Chandra observation of a ∼2 L * late-type galaxy, ESO 137-002, in the closest rich cluster A3627. The Chandra data reveal a long (∼>40 kpc) and narrow tail with a nearly constant width (∼3 kpc) to the southeast of the galaxy, and a leading edge ∼1.5 kpc from the galaxy center on the upstream side of the tail. The tail is most likely caused by the nearly edge-on stripping of ESO 137-002's interstellar medium (ISM) by ram pressure, compared to the nearly face-on stripping of ESO 137-001 discussed in our previous work. Spectral analysis of individual regions along the tail shows that the gas throughout it has a rather constant temperature, ∼1 keV, very close to the temperature of the tails of ESO 137-001, if the same atomic database is used. The derived gas abundance is low (∼0.2 solar with the single-kT model), an indication of the multiphase nature of the gas in the tail. The mass of the X-ray tail is only a small fraction (<5%) of the initial ISM mass of the galaxy, suggesting that the stripping is most likely at an early stage. However, with any of the single-kT, double-kT, and multi-kT models we tried, the tail is always 'over-pressured' relative to the surrounding intracluster medium (ICM), which could be due to the uncertainties in the abundance, thermal versus non-thermal X-ray emission, or magnetic support in the ICM. The Hα data from the Southern Observatory for Astrophysical Research show a ∼21 kpc tail spatially coincident with the X-ray tail, as well as a secondary tail (∼12 kpc long) to the east of the main tail diverging at an angle of ∼23° and starting at a distance of ∼7.5 kpc from the nucleus. At the position of the secondary Hα tail, the X-ray emission is also enhanced at the ∼2σ level. We compare the tails of ESO 137-001 and ESO 137-002, and also compare the tails to simulations. Both the similarities and differences of the tails pose challenges to the simulations. Several implications are

  19. Tailings management best practice: a case study of the McClean Lake JEB Tailings Management Facility

    International Nuclear Information System (INIS)

    Tremblay, M.A.J.; Rowson, J.

    2005-01-01

    COGEMA Resources Inc. (which is part of the Areva Group) is a Canadian company with its head office in Saskatoon, Saskatchewan. It owns and operates mining and milling facilities in Northern Saskatchewan, which produce uranium concentrate. McClean Lake Operation commenced production in 1999 and its tailings management facility represents the state of the art for tailings management in the uranium industry in Canada. Tailings disposal has the potential to cause effects in the surrounding receiving environment primarily through migration of soluble constituents from the facility to surface water receptors. In-pit disposal or mill tailings has become the standard in the uranium mining industry in Northern Saskatchewan. This method or tailings management demonstrates advances in terms of worker radiation protection and containment of soluble constituents both during operations and into the long term. Sub-aqueous deposition of tailings protects personnel from exposure to radiation and airborne emissions and prevents freezing of tailings, which can hinder consolidation. The continuous inflow of groundwater to the facility is achieved during operations, through control of water levels within the facility. This ensures hydrodynamic containment, which prevents migration of soluble radionuclides and heavy metals into the surrounding aquifer during operations. The environmental performance of the decommissioned facility depends upon the rate of release of contaminants to the receiving environment. The rate of constituent loading to the receiving environment will ultimately be governed by the concentrations of soluble constituents within the tailings mass, the mechanisms for release from the tailings to the surrounding groundwater system, and transport of constituents within the groundwater pathway to the receiving environment. The tailings preparation process was designed to convert arsenic into a stable form to reduce soluble concentrations within the tailings mass. The

  20. A proactive approach to sustainable management of mine tailings

    Science.gov (United States)

    Edraki, Mansour; Baumgartl, Thomas

    2015-04-01

    The reactive strategies to manage mine tailings i.e. containment of slurries of tailings in tailings storage facilities (TSF's) and remediation of tailings solids or tailings seepage water after the decommissioning of those facilities, can be technically inefficient to eliminate environmental risks (e.g. prevent dispersion of contaminants and catastrophic dam wall failures), pose a long term economic burden for companies, governments and society after mine closure, and often fail to meet community expectations. Most preventive environmental management practices promote proactive integrated approaches to waste management whereby the source of environmental issues are identified to help make a more informed decisions. They often use life cycle assessment to find the "hot spots" of environmental burdens. This kind of approach is often based on generic data and has rarely been used for tailings. Besides, life cycle assessments are less useful for designing operations or simulating changes in the process and consequent environmental outcomes. It is evident that an integrated approach for tailings research linked to better processing options is needed. A literature review revealed that there are only few examples of integrated approaches. The aim of this project is to develop new tailings management models by streamlining orebody characterization, process optimization and rehabilitation. The approach is based on continuous fingerprinting of geochemical processes from orebody to tailings storage facility, and benchmark the success of such proactive initiatives by evidence of no impacts and no future projected impacts on receiving environments. We present an approach for developing such a framework and preliminary results from a case study where combined grinding and flotation models developed using geometallurgical data from the orebody were constructed to predict the properties of tailings produced under various processing scenarios. The modelling scenarios based on the