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Sample records for amalgam fillings associations

  1. About Dental Amalgam Fillings

    Science.gov (United States)

    ... and Medical Procedures Dental Devices Dental Amalgam About Dental Amalgam Fillings Share Tweet Linkedin Pin it More ... should I have my fillings removed? What is dental amalgam? Dental amalgam is a dental filling material ...

  2. Association between History of Dental Amalgam Fillings and Risk of Parkinson's Disease: A Population-Based Retrospective Cohort Study in Taiwan.

    Directory of Open Access Journals (Sweden)

    Yung-Chuang Hsu

    Full Text Available The impact of dental amalgam on the development of Parkinson's disease (PD is still uncertain, although a positive association between dental amalgam and PD has been found in a few case-control studies. The patients with amalgam fillings restored between 2000 and 2008 were identified by using the National Health Insurance Research Database (NHIRD in Taiwan. The same number of patients who had no new amalgam filling restored was matched by sex, age, and treatment date. Both cohorts were followed up from the treatment date until the date of diagnosis of PD, death, or the end of the year 2008. The individuals who received amalgam fillings had a significantly higher risk of PD afterward (adjusted hazard ratio [HR]=1.583, 95% confidence interval [CI]=1.122-2.234, p=0.0089 than those who did not. In the individuals who received amalgam fillings, being diagnosed with diabetes or hyperlipidemia demonstrated a significantly lower HR of PD occurrence than in the patients without diabetes or hyperlipidemia (HR=0.449, 95% CI=0.254-0.794, p=0.0059; HR=0.445, 95% CI=0.260-0.763, p=0.0032 after adjusting for comorbidities and Charlson-Deyo Comorbidity Index (CCI scores. Meanwhile, hypertension increased the hazard risk of PD (HR=1.645, 95% CI=1.098-2.464, p=0.0159. The patients exposed to dental amalgam fillings were 1.583 times more likely to have PD afterward compared to their non-exposed counterparts after adjusting for comorbidities and CCI scores.

  3. [Creep of amalgam fillings under clasp rests].

    Science.gov (United States)

    Borchers, L; Jung, T; West, M

    1989-10-01

    A clinically realistic experiment was set up to obtain information on the amount of vertical settling of clasp rests in amalgam restorations under functional loading. Mesioocclusal cavities were prepared in 16 lower molar specimens cast in brass. The cavities were filled with amalgam and provided with a mesial rest seat. A constant load of 100 N was applied via a simplified (experimental) saddle to a cobalt-chromium E-clasp cast to the saddle. The duration of the load corresponded to 160 days of clinical function. The chronological course of vertical displacement was analyzed mathematically. According to this result the process can be divided into three components: settling immediately upon load initiation (mean value 96 microns, transition creep (mean value 25 microns) and creep ata constant rate (mean value 15 microns). The mean overall vertical displacement of the rests was 136 microns, the maximum value 287 microns. These findings suggest that vertical settling of a clasp rest into its seat in an amalgam restoration may eventually result in significant changes in occlusion and may almost completely exhaust gingival resilience.

  4. Maternal-fetal distribution of mercury ( sup 203 Hg) released from dental amalgam fillings

    Energy Technology Data Exchange (ETDEWEB)

    Vimy, M.J.; Takahashi, Y.; Lorscheider, F.L. (Univ. of Calgary, Alberta (Canada))

    1990-04-01

    In humans, the continuous release of Hg vapor from dental amalgam tooth restorations is markedly increased for prolonged periods after chewing. The present study establishes a time-course distribution for amalgam Hg in body tissues of adult and fetal sheep. Under general anesthesia, five pregnant ewes had twelve occlusal amalgam fillings containing radioactive 203Hg placed in teeth at 112 days gestation. Blood, amniotic fluid, feces, and urine specimens were collected at 1- to 3-day intervals for 16 days. From days 16-140 after amalgam placement (16-41 days for fetal lambs), tissue specimens were analyzed for radioactivity, and total Hg concentrations were calculated. Results demonstrate that Hg from dental amalgam will appear in maternal and fetal blood and amniotic fluid within 2 days after placement of amalgam tooth restorations. Excretion of some of this Hg will also commence within 2 days. All tissues examined displayed Hg accumulation. Highest concentrations of Hg from amalgam in the adult occurred in kidney and liver, whereas in the fetus the highest amalgam Hg concentrations appeared in liver and pituitary gland. The placenta progressively concentrated Hg as gestation advanced to term, and milk concentration of amalgam Hg postpartum provides a potential source of Hg exposure to the newborn. It is concluded that accumulation of amalgam Hg progresses in maternal and fetal tissues to a steady state with advancing gestation and is maintained. Dental amalgam usage as a tooth restorative material in pregnant women and children should be reconsidered.

  5. Maternal-fetal distribution of mercury (203Hg) released from dental amalgam fillings

    International Nuclear Information System (INIS)

    Vimy, M.J.; Takahashi, Y.; Lorscheider, F.L.

    1990-01-01

    In humans, the continuous release of Hg vapor from dental amalgam tooth restorations is markedly increased for prolonged periods after chewing. The present study establishes a time-course distribution for amalgam Hg in body tissues of adult and fetal sheep. Under general anesthesia, five pregnant ewes had twelve occlusal amalgam fillings containing radioactive 203Hg placed in teeth at 112 days gestation. Blood, amniotic fluid, feces, and urine specimens were collected at 1- to 3-day intervals for 16 days. From days 16-140 after amalgam placement (16-41 days for fetal lambs), tissue specimens were analyzed for radioactivity, and total Hg concentrations were calculated. Results demonstrate that Hg from dental amalgam will appear in maternal and fetal blood and amniotic fluid within 2 days after placement of amalgam tooth restorations. Excretion of some of this Hg will also commence within 2 days. All tissues examined displayed Hg accumulation. Highest concentrations of Hg from amalgam in the adult occurred in kidney and liver, whereas in the fetus the highest amalgam Hg concentrations appeared in liver and pituitary gland. The placenta progressively concentrated Hg as gestation advanced to term, and milk concentration of amalgam Hg postpartum provides a potential source of Hg exposure to the newborn. It is concluded that accumulation of amalgam Hg progresses in maternal and fetal tissues to a steady state with advancing gestation and is maintained. Dental amalgam usage as a tooth restorative material in pregnant women and children should be reconsidered

  6. Dental Amalgam

    Science.gov (United States)

    ... Products and Medical Procedures Dental Devices Dental Amalgam Dental Amalgam Share Tweet Linkedin Pin it More sharing options Linkedin Pin it Email Print Dental amalgam is a dental filling material which is ...

  7. High-field MRI and mercury release from dental amalgam fillings.

    Science.gov (United States)

    Mortazavi, S M J; Neghab, M; Anoosheh, S M H; Bahaeddini, N; Mortazavi, G; Neghab, P; Rajaeifard, A

    2014-04-01

    Mercury is among the most toxic nonradioactive elements which may cause toxicity even at low doses. Some studies showed release of mercury from dental amalgam fillings in individuals who used mobile phone. This study was conducted to assess the effect of high-field MRI on mercury release from dental amalgam filling. We studied two groups of students with identical tooth decays requiring a similar pattern of restorative dentistry. They were exposed to a magnetic flux density of 1.5 T produced by a MRI machine. 16 otherwise healthy students with identical dental decay participated in this study. They underwent similar restorative dentistry procedures and randomly divided into two groups of MRI-exposed and control arms. Urinary concentrations of mercury in the control subjects were measured before (hour 0) and 48 and 72 hrs after amalgam restoration, using cold vapor atomic absorption spectrometry. Urinary concentrations of mercury in exposed individuals were determined before (hour 0), and 24, 48, 72 and 96 hrs after amalgam restoration. Unlike control subjects, they underwent conventional brain MRI (15 min, 99 slices), 24 hrs after amalgam restoration. The mean±SD urinary mercury levels in MRI-exposed individuals increased linearly from a baseline value of 20.70±17.96 to 24.83±22.91 μg/L 72 hrs after MRI. In the control group, the concentration decreased linearly from 20.70±19.77 to 16.14±20.05 μg/L. The difference between urinary mercury in the exposed and control group, 72 hrs after MRI (96 h after restoration),was significant (p=0.046). These findings provide further support for the noxious effect of MRI (exposure to strong magnetic field)and release of mercury from dental amalgam fillings.

  8. High-Field MRI and Mercury Release from Dental Amalgam Fillings

    Directory of Open Access Journals (Sweden)

    SMJ Mortazavi

    2014-04-01

    Full Text Available Mercury is among the most toxic nonradioactive elements which may cause toxicity even at low doses. Some studies showed release of mercury from dental amalgam fillings in individuals who used mobile phone. This study was conducted to assess the effect of high-field MRI on mercury release from dental amalgam filling. We studied two groups of students with identical tooth decays requiring a similar pattern of restorative dentistry. They were exposed to a magnetic flux density of 1.5 T produced by a MRI machine. 16 otherwise healthy students with identical dental decay participated in this study. They underwent similar restorative dentistry procedures and randomly divided into two groups of MRI-exposed and control arms. Urinary concentrations of mercury in the control subjects were measured before (hour 0 and 48 and 72 hrs after amalgam restoration, using cold vapor atomic absorption spectrometry. Urinary concentrations of mercury in exposed individuals were determined before (hour 0, and 24, 48, 72 and 96 hrs after amalgam restoration. Unlike control subjects, they underwent conventional brain MRI (15 min, 99 slices, 24 hrs after amalgam restoration. The mean±SD urinary mercury levels in MRI-exposed individuals increased linearly from a baseline value of 20.70±17.96 to 24.83±22.91 μg/L 72 hrs after MRI. In the control group, the concentration decreased linearly from 20.70±19.77 to 16.14±20.05 μg/L. The difference between urinary mercury in the exposed and control group, 72 hrs after MRI (96 h after restoration,was significant (p=0.046. These findings provide further support for the noxious effect of MRI (exposure to strong magnetic fieldand release of mercury from dental amalgam fillings.

  9. Effect of bleaching on mercury release from amalgam fillings and antioxidant enzyme activities: a pilot study.

    Science.gov (United States)

    Cakir, Filiz Yalcin; Ergin, Esra; Gurgan, Sevil; Sabuncuoglu, Suna; Arpa, Cigdem Sahin; Tokgoz, İlknur; Ozgunes, Hilal; Kiremitci, Arlin

    2015-01-01

    The aim of this pilot clinical study was to determine the mercury release from amalgam fillings and antioxidant enzyme activities (Superoxide Dismutase [SOD] and Catalase[CAT] ) in body fluids after exposure to two different vital tooth bleaching systems. Twenty eight subjects with an average age of 25.6 years (18-41) having at least two but not more than four Class II amalgam fillings on each quadrant arch in the mouth participated in the study. Baseline concentrations of mercury levels in whole blood, urine, and saliva were measured by a Vapor Generation Accessory connected to an Atomic Absorption Spectrometer. Erythrocyte enzymes, SOD, and CAT activities in blood were determined kinetically. Subjects were randomly assigned to two groups of 14 volunteers. Group 1 was treated with an at-home bleaching system (Opalescence PF 35% Carbamide Peroxide, Ultradent), and Group 2 was treated with a chemically activated office bleaching system (Opalescence Xtra Boost 38% Hydrogen Peroxide, Ultradent) according to the manufacturer's recommendations. Twenty-four hours after bleaching treatments, concentrations of mercury and enzymes were remeasured. There were no significant differences on mercury levels in blood, urine, and saliva before and after bleaching treatments (p > 0.05). No differences were also found in the level of antioxidant enzyme activities (SOD and CAT) before and after treatments (p > 0.05). Mercury release did not affect the enzyme activities (p > 0.05). Bleaching treatments either office or home did not affect the amount of mercury released from amalgam fillings in blood, urine, and saliva and the antioxidant-enzyme activities in blood. Bleaching treatments with the systems tested in this pilot study have no deleterious effect on the mercury release from amalgam fillings and antioxidant enzymes in body fluids. © 2014 Wiley Periodicals, Inc.

  10. Radioisotopes in the study of the adaptation of dental amalgam fillings

    International Nuclear Information System (INIS)

    Bermawi, A.

    1995-02-01

    Adaptation expresses the significance of the relationship between the dental filling and its cavity, and forms a special challenge for the dentist when he performs dental restorative procedures. Therefore, I have done a study on the adaptation of dental amalgam fillings and their marginal leakage using radioactive iodine (I sup 1 sup 3 sup 1) and radioactive carbon (C sup 1 sup 4) on three alloys: Viva cap-Contour-Sybraloy. Marginal leakage has been established by the use of I sup 1 sup 3 sup 1, and the leakage points located by C sup 1 sup 4, by means of radioautography. This study was carried out on: - 45 dental specimens to examine marginal leakage. - 9 dental specimens to examine the time of leakage as it reached the occlusal surface. - 6 dental specimens to examine the effect of lining the cavity walls with NO sup 3 Ag varnish on marginal leakage. - 5 dental specimens to examine the effect of form (bevel) of pulpal axial point angle on marginal leakage. - 3 dental specimens as controls. - 25 dental specimens for radioautography, and to determine leakage points. The following results were observed: - Leakage occurred around the contours of all fillings under study, and spread from their basal parts to the angle of their occlusal margin. - Quantitative increase of leakage with time. - The type of the alloy played an active role in determining the pattern of leakage. - Metallic amalgam alloys with spheroidal regular atoms showed the least leakage. - The occlusal sulci exhibited more leakage than the other parts. - Beveling the pulpal axial point angle decreased leakage. - Lining the cavity walls with NO sup 3 Ag varnish inhibited leakage. - The radioactive element, to which the specimens were exposed, was unable to infiltrated and penetrate dentinal and enamel tissues. (author). 55 refs, 52 figs., 68 tabs

  11. Radioisotopes in the study of the adaptation of dental amalgam fillings

    Energy Technology Data Exchange (ETDEWEB)

    Bermawi, A [Atomic Energy Commission, Damascus (Syrian Arab Republic). Dept. of Radiation Protection and Nuclear Safety

    1995-02-01

    Adaptation expresses the significance of the relationship between the dental filling and its cavity, and forms a special challenge for the dentist when he performs dental restorative procedures. Therefore, I have done a study on the adaptation of dental amalgam fillings and their marginal leakage using radioactive iodine (I sup 1 sup 3 sup 1) and radioactive carbon (C sup 1 sup 4) on three alloys: Viva cap-Contour-Sybraloy. Marginal leakage has been established by the use of I sup 1 sup 3 sup 1, and the leakage points located by C sup 1 sup 4, by means of radioautography. This study was carried out on: - 45 dental specimens to examine marginal leakage. - 9 dental specimens to examine the time of leakage as it reached the occlusal surface. - 6 dental specimens to examine the effect of lining the cavity walls with NO sup 3 Ag varnish on marginal leakage. - 5 dental specimens to examine the effect of form (bevel) of pulpal axial point angle on marginal leakage. - 3 dental specimens as controls. - 25 dental specimens for radioautography, and to determine leakage points. The following results were observed: - Leakage occurred around the contours of all fillings under study, and spread from their basal parts to the angle of their occlusal margin. - Quantitative increase of leakage with time. - The type of the alloy played an active role in determining the pattern of leakage. - Metallic amalgam alloys with spheroidal regular atoms showed the least leakage. - The occlusal sulci exhibited more leakage than the other parts. - Beveling the pulpal axial point angle decreased leakage. - Lining the cavity walls with NO sup 3 Ag varnish inhibited leakage. - The radioactive element, to which the specimens were exposed, was unable to infiltrated and penetrate dentinal and enamel tissues. (author). 55 refs, 52 figs., 68 tabs.

  12. Increased Zn/Glutathione Levels and Higher Superoxide Dismutase-1 Activity as Biomarkers of Oxidative Stress in Women with Long-Term Dental Amalgam Fillings: Correlation between Mercury/Aluminium Levels (in Hair) and Antioxidant Systems in Plasma

    Science.gov (United States)

    Cabaña-Muñoz, María Eugenia; Parmigiani-Izquierdo, José María; Bravo-González, Luis Alberto; Kyung, Hee-Moon; Merino, José Joaquín

    2015-01-01

    Background The induction of oxidative stress by Hg can affect antioxidant enzymes. However, epidemiological studies have failed to establish clear association between dental fillings presence and health problems. Objectives To determine whether heavy metals (in hair), antioxidant enzymes (SOD-1) and glutathione levels could be affected by the chronic presence of heavy metals in women who had dental amalgam fillings. Materials and Methods 55 hair samples (42 females with amalgam fillings and 13 female control subjects) were obtained. All subjects (mean age 44 years) who had dental amalgam filling for more than 10 years (average 15 years). Certain metals were quantified by ICP-MS (Mass Spectrophotometry) in hair (μg/g: Al, Hg, Ba, Ag, Sb, As, Be, Bi, Cd, Pb, Pt, Tl, Th, U, Ni, Sn, Ti) and SOD-1 and Glutathione (reduced form) levels in plasma. Data were compared with controls without amalgams, and analyzed to identify any significant relation between metals and the total number of amalgam fillings, comparing those with four or less (n = 27) with those with more than four (n = 15). As no significant differences were detected, the two groups were pooled (Amlgam; n = 42). Findings Hg, Ag, Al and Ba were higher in the amalgam group but without significant differences for most of the heavy metals analyzed. Increased SOD-1 activity and glutathione levels (reduced form) were observed in the amalgam group. Aluminum (Al) correlated with glutathione levels while Hg levels correlated with SOD-1. The observed Al/glutathione and Hg/SOD-1 correlation could be adaptive responses against the chronic presence of mercury. Conclusions Hg, Ag, Al and Ba levels increased in women who had dental amalgam fillings for long periods. Al correlated with glutathione, and Hg with SOD-1. SOD-1 may be a possible biomarker for assessing chronic Hg toxicity. PMID:26076368

  13. Molar apicectomy with amalgam root-end filling: results of a prospective study in two district general hospitals.

    Science.gov (United States)

    Wesson, C M; Gale, T M

    2003-12-20

    To determine the five-year success rates, site or sites of failure, prognostic indicators and lower lip morbidity associated with molar apicectomy using amalgam root-end filling. Multicentre, prospective study. The departments of oral and maxillo-facial surgery in two district general hospitals. One thousand and seven molar apicectomy procedures, combined with amalgam root-end filling were expedited during the period 1974-1995. A five-year review of each operated tooth was carried out or attempted between 1979-2000. Of the 790 (78%) operated molars successfully reviewed at 5 years or later 451 (57%) exhibited 'complete healing' and 39 (5%) 'uncertain healing'. Three hundred (38%) were classified as 'unsatisfactory healing' (failures), and these included 12 which were assumed to be of periodontal origin. Whilst longitudinal root fracture, perforation and/or infection in the furcation, periodontal disease or a non-restorable crown accounted for treatment failure and often the need to remove teeth subsequently, the study probably pointed to the apical ends of the roots rather than the furcation as being the major sites at which 'unsatisfactory healing' occurred. Mandibular first molars attracted the highest 'complete healing' rate (60%) and mandibular second molars the lowest (46%). 'Good' root canal treatment (RCT) at the outset improved the prognosis of a root-end filling (REF) whilst the absence of RCT compromised it. Cystic change pointed to a better prognosis than apical granulomatous change as did a deep compared with a shallow 'bone cuff'. Disease at the furcation suggested a worse prognosis. Teeth which showed 'complete healing' at 1 year had a 75% probability of maintaining this outcome at 5 years. Sensory disturbance of variable duration occurred in the lower lip following 20-21% of mandibular molar procedures. In the majority of cases (79-80%) this had remitted within 3 months. A permanent deficit occurred in 8 patients (1%) where the apicectomy could

  14. Extensive amalgam tattoo on the alveolar-gingival mucosa.

    Science.gov (United States)

    Galletta, Vivian C; Artico, Gabriela; Dal Vechio, Aluana M C; Lemos, Celso A; Migliari, Dante A

    2011-01-01

    Amalgam tattoos are common exogenous pigmented lesions of the oral mucosa occurring mainly by inadvertent placement of amalgam particles into soft tissues. The diagnosis of amalgam tattoo is simple, usually based on clinical findings associated with presence or history of amalgam fillings removal. Intraoral X-rays may be helpful in detecting amalgam-related radiopacity. In cases where amalgam tattoo cannot be differentiated from other causes of oral pigmentation, a biopsy should be performed. This article deals with an extensive amalgam tattoo lesion which required a biopsy for a definitive diagnosis.

  15. Mercury concentration in maternal serum, cord blood, and placenta in patients with amalgam dental fillings: effects on fetal biometric measurements.

    Science.gov (United States)

    Bedir Findik, Rahime; Celik, Huseyin Tugrul; Ersoy, Ali Ozgur; Tasci, Yasemin; Moraloglu, Ozlem; Karakaya, Jale

    2016-11-01

    We aimed to determine the extent to which mercury is transmitted from the mother to fetus via the umbilical cord in patients with amalgam dental fillings, and its effect on fetal biometric measurements. Twenty-eight patients as the study group with amalgam fillings, and 32 of them as the control group were included in this prospective case-control study. The mercury levels were measured in the maternal and cord venous sera, and the placental samples. Two groups were compared in terms of these and the fetal/neonatal biometric measurements. In the study group, the maternal and umbilical cord mercury levels were found to be significantly higher than those from the control group (p = 0.006 and p = 0.010, respectively). These high levels did not affect the fetal biometric measurements. The presence of high serum mercury levels in pregnant women with amalgam fillings is important, and warrants further long-term studies in order to investigate the fetal neurological effects as well.

  16. Comparative X-ray studies on the behaviour of amalgam and gold fillings at the margins in the approximal space as a function of time of residence

    International Nuclear Information System (INIS)

    Hansen, R.

    1982-01-01

    Within the framework of this thesis, X-ray pictures have been made of 430 gold or amalgam fillings in order to measure the gap between approximal cavity margin and filling margin. With amalgam fillings, the gap width measured after a residence time of half a year was 9.3 μm and widened to 136.9 μm after 8 years, which represents an increase to the 14-fold. The gap widths measured with gold inlays only doubled within this period, increasing from 38.8 μm after half a year to 77.4 μm after 8 years. The number of retention spots found in the approximal-cervical space with amalgam fillings was at least twice that found for gold fillings. From this it is concluded that gold inlays are by far the better solution for dental restorations. (orig./MG) [de

  17. Compressive strength and failure types of cusp replacing direct resin composite restorations in previously amalgam-filled premolars versus sound teeth

    NARCIS (Netherlands)

    Scholtanus, Johannes Durk; Zaia, John; Oezcan, Mutlu

    2017-01-01

    This study evaluated the fracture resistance of cusp replacing direct resin composite restorations (DCR) in premolars that had been previously filled with amalgam mesial-occlusal-distal (MOD) restorations and compared their fracture resistance with those made on sound dentin and intact teeth.

  18. Increased Release of Mercury from Dental Amalgam Fillings due to Maternal Exposure to Electromagnetic Fields as a Possible Mechanism for the High Rates of Autism in the Offspring: Introducing a Hypothesis

    Directory of Open Access Journals (Sweden)

    Mortazavi Gh.

    2016-03-01

    Full Text Available According to the World Health Organization (WHO, factors such as growing electricity demand, ever-advancing technologies and changes in social behaviour have led to steadily increasing exposure to man-made electromagnetic fields. Dental amalgam fillings are among the major sources of exposure to elemental mercury vapour in the general population. Although it was previously believed that low levels are mercury (i.g. release of mercury from dental amalgam is not hazardous, now numerous data indicate that even very low doses of mercury cause toxicity. There are some evidence indicating that perinatal exposure to mercury is significantly associated with an increased risk of developmental disorders such as autism spectrum disorders (ASD and attention-deficit hyperactivity disorder (ADHD. Furthermore, mercury can decrease the levels of neurotransmitters dopamine, serotonin, noreprenephrine, and acetylcholine in the brain and cause neurological problems. On the other hand, a strong positive correlation between maternal and cord blood mercury levels is found in some studies. We have previously shown that exposure to MRI or microwave radiation emitted by common mobile phones can lead to increased release of mercury from dental amalgam fillings. Moreover, when we investigated the effects of MRI machines with stronger magnetic fields, our previous findings were confirmed. As a strong association between exposure to electromagnetic fields and mercury level has been found in our previous studies, our findings can lead us to this conclusion that maternal exposure to electromagnetic fields in mothers with dental amalgam fillings may cause elevated levels of mercury and trigger the increase in autism rates. Further studies are needed to have a better understanding of the possible role of the increased mercury level after exposure to electromagnetic fields and the rate of autism spectrum disorders in the offspring.

  19. Micro-PIXE study of metal loss from dental amalgam

    Science.gov (United States)

    Meesat, Ridthee; Sudprasert, Wanwisa; Guibert, Edouard; Wang, Liping; Chappuis, Thibault; Whitlow, Harry J.

    2017-08-01

    Mercury amalgams have been a topic of controversy ever since their introduction over 150 years ago as a dental material. An interesting question is if metals are released from the amalgam into the enamel and dentine tissue. To elucidate this PIXE mapping was used to investigate metal redistribution in an extracted molar tooth with a ∼30 year old high-Cu content amalgam filling. The tooth was sectioned and polished, and elemental mapping carried out on the amalgam/enamel, bulk amalgam and the wear surface of the amalgam. As expected, the amalgam was multiphase amalgam comprising of Cu-rich and Ag-rich grains with non-uniform distribution of Hg. The amalgam/dentine interface was clearly defined with amalgam elements on one side and C and P from hydroxyapatite on the other side with evidence of only slight interface corrosion. The peaks for Cu Hg and Zn were isolated from interfering signals with concentrations in the enamel tissue, observed to be at, or below the method detection limit. The proximity in energy of the Sn L α and Ca K α , peaks and the background on the Hg M α gave signal overlap which increased the MDL for these elements. Remarkably, a course grain texture in the amalgam was observed just below the biting surface of the amalgam which might be associated with tribochemical processes from mastication. This coupled with the clear absence of the amalgam metals from tooth tissue, even in close proximity to the interface, suggests that for this sample, release of Hg occurred via erosion or dissolution in saliva.

  20. Mercury (Hg) burden in children: The impact of dental amalgam

    Energy Technology Data Exchange (ETDEWEB)

    Al-Saleh, Iman, E-mail: iman@kfshrc.edu.sa [Biological and Medical Research Department, King Faisal Specialist Hospital and Research Centre, PO Box: 3354, Riyadh 11211 (Saudi Arabia); Al-Sedairi, Al anoud [Department of Zoology, College of Science, King Saud University, PO Box: 24452, Riyadh 11495 (Saudi Arabia)

    2011-07-15

    The risks and benefits of using mercury (Hg) in dental amalgam have long been debated. This study was designed to estimate Hg body burden and its association with dental amalgam fillings in 182 children (ages: 5-15 years) living in Taif City. Hg was measured in urine (UHg), hair (HHg) and toenails (NHg) by the Atomic Absorption Spectrophotometer with Vapor Generator Accessory system. Urinary Hg levels were calculated as both micrograms per gram creatinine ({mu}g/g creatinine) and micrograms per liter ({mu}g/L). We found that children with amalgam fillings (N = 106) had significantly higher UHg-C levels than children without (N = 76), with means of 3.763 {mu}g/g creatinine versus 3.457 {mu}g/g creatinine, respectively (P = 0.019). The results were similar for UHg (P = 0.01). A similar pattern was also seen for HHg, with means of 0.614 {mu}g/g (N = 97) for children with amalgam versus 0.242 {mu}g/g (N = 74) for those without amalgam fillings (P = 0). Although the mean NHg was higher in children without amalgam (0.222 {mu}g/g, N = 61) versus those with (0.163 {mu}g/g, N = 101), the relationship was not significant (P = 0.069). After adjusting for many confounders, the multiple logistic regression model revealed that the levels of UHg-C and HHg were 2.047 and 5.396 times higher, respectively, in children with dental amalgam compared to those without (P < 0.01). In contrast, a significant inverse relationship was seen between NHg levels and dental amalgam fillings (P = 0.003). Despite the controversy surrounding the health impact of dental amalgam, this study showed some evidence that amalgam-associated Hg exposure might be related with symptoms of oral health, such as aphthous ulcer, white patches, and a burning-mouth sensation. Further studies are needed to reproduce these findings. The present study showed that significant numbers of children with or without amalgam had Hg levels exceeding the acceptable reference limits. The detrimental neurobehavioral and

  1. Mercury (Hg) burden in children: The impact of dental amalgam

    International Nuclear Information System (INIS)

    Al-Saleh, Iman; Al-Sedairi, Al anoud

    2011-01-01

    The risks and benefits of using mercury (Hg) in dental amalgam have long been debated. This study was designed to estimate Hg body burden and its association with dental amalgam fillings in 182 children (ages: 5-15 years) living in Taif City. Hg was measured in urine (UHg), hair (HHg) and toenails (NHg) by the Atomic Absorption Spectrophotometer with Vapor Generator Accessory system. Urinary Hg levels were calculated as both micrograms per gram creatinine (μg/g creatinine) and micrograms per liter (μg/L). We found that children with amalgam fillings (N = 106) had significantly higher UHg-C levels than children without (N = 76), with means of 3.763 μg/g creatinine versus 3.457 μg/g creatinine, respectively (P = 0.019). The results were similar for UHg (P = 0.01). A similar pattern was also seen for HHg, with means of 0.614 μg/g (N = 97) for children with amalgam versus 0.242 μg/g (N = 74) for those without amalgam fillings (P = 0). Although the mean NHg was higher in children without amalgam (0.222 μg/g, N = 61) versus those with (0.163 μg/g, N = 101), the relationship was not significant (P = 0.069). After adjusting for many confounders, the multiple logistic regression model revealed that the levels of UHg-C and HHg were 2.047 and 5.396 times higher, respectively, in children with dental amalgam compared to those without (P < 0.01). In contrast, a significant inverse relationship was seen between NHg levels and dental amalgam fillings (P = 0.003). Despite the controversy surrounding the health impact of dental amalgam, this study showed some evidence that amalgam-associated Hg exposure might be related with symptoms of oral health, such as aphthous ulcer, white patches, and a burning-mouth sensation. Further studies are needed to reproduce these findings. The present study showed that significant numbers of children with or without amalgam had Hg levels exceeding the acceptable reference limits. The detrimental neurobehavioral and/or nephrotoxic effects of

  2. Allelic loss in amalgam-associated oral lichenoid lesions compared to oral lichen planus and mucosa.

    Science.gov (United States)

    Rodrigues, L N; Sousa, S F; Silva, Rcc; Abreu, Mhg; Pires, F R; Mesquita, R A; Bastos-Rodrigues, L; De Marco, L; Gomes, C C; Gomez, R S; Bernardes, V F

    2017-05-01

    The amalgam-associated oral lichenoid lesion (AAOLL) shows clinical and histopathological features similar to oral lichen planus (OLP). Molecular researches to improve knowledge of pathogenesis and clinical behavior of AAOLL are still scarce. We investigated for the first time the use of loss of heterozygosity (LOH) as a molecular approach for genetic characterization of AAOLL in comparison with OLP and evaluated the cell proliferation index. The sample comprised nine AAOLLs, 10 OLPs, and eight NOMs matched by patients' gender and age. LOH was assessed using polymorphic microsatellite markers at chromosomes 9p (D9S157, D9S162, D9S171), 11q (D11S1369), and 17p (TP53, AFM238WF2). Cell proliferation was assessed by immunohistochemical expression of Ki-67 (MIB-1). The association between LOH and Ki-67 was investigated. Loss of heterozygosity occurred in 5/9 AAOLLs and in 2/10 OLPs in at least one marker each, while NOM showed no LOH. Cell proliferation index in AAOLL ranged from 2 to 23%. There was no association between cell proliferation and LOH, independent of the marker. Our study shows that the profile of molecular changes in AAOLL and OLP, evaluated by LOH and Ki-67 expression, is similar. Additional studies including larger samples should be performed to confirm or to refute our findings. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. Prenatal exposure to dental amalgam in the Seychelles Child Development Nutrition Study: associations with neurodevelopmental outcomes at 9 and 30 months.

    Science.gov (United States)

    Watson, Gene E; Evans, Katie; Thurston, Sally W; van Wijngaarden, Edwin; Wallace, Julie M W; McSorley, Emeir M; Bonham, Maxine P; Mulhern, Maria S; McAfee, Alison J; Davidson, Philip W; Shamlaye, Conrad F; Strain, J J; Love, Tanzy; Zareba, Grazyna; Myers, Gary J

    2012-12-01

    Dental amalgam is approximately 50% metallic mercury and releases mercury vapor into the oral cavity, where it is inhaled and absorbed. Maternal amalgams expose the developing fetus to mercury vapor. Mercury vapor can be toxic, but uncertainty remains whether prenatal amalgam exposure is associated with neurodevelopmental consequences in offspring. To determine if prenatal mercury vapor exposure from maternal dental amalgam is associated with adverse effects to cognition and development in children. We prospectively determined dental amalgam status in a cohort of 300 pregnant women recruited in 2001 in the Republic of Seychelles to study the risks and benefits of fish consumption. The primary exposure measure was maternal amalgam surfaces present during gestation. Maternal occlusal points were a secondary measure. Outcomes were the child's mental (MDI) and psychomotor (PDI) developmental indices of the Bayley Scales of Infant Development-II (BSID-II) administered at 9 and 30 months. Complete exposure, outcome, and covariate data were available on a subset of 242 mother-child pairs. The number of amalgam surfaces was not significantly (p>0.05) associated with either PDI or MDI scores. Similarly, secondary analysis with occlusal points showed no effect on the PDI or MDI scores for boys and girls combined. However, secondary analysis of the 9-month MDI was suggestive of an adverse association present only in girls. We found no evidence of an association between our primary exposure metric, amalgam surfaces, and neurodevelopmental endpoints. Secondary analyses using occlusal points supported these findings, but suggested the possibility of an adverse association with the MDI for girls at 9 months. Given the continued widespread use of dental amalgam, we believe additional prospective studies to clarify this issue are a priority. Copyright © 2012 Elsevier Inc. All rights reserved.

  4. The environmental effects of dental amalgam.

    Science.gov (United States)

    Chin, G; Chong, J; Kluczewska, A; Lau, A; Gorjy, S; Tennant, M

    2000-12-01

    Dental amalgam is one of the most commonly used materials in restorative dentistry. However, one of its major components, mercury, is of particular concern due to its potential adverse effects on humans and the environment. In this review, the environmental impact of dental amalgam will be discussed, with particular reference to the effects attributed to its mercury component. Mercury commonly occurs in nature as sulfides and in a number of minerals. Globally, between 20,000-30,000 tons of mercury are discharged into the environment each year as a result of human activities. According to a recent German report, approximately 46 per cent of the freshly triturated amalgam is inserted as new amalgam restorations and the rest is waste. Depending on the presence of an amalgam separating unit, some of the generated amalgam-contaminated sludge is discharged into the sewage system. Lost or extracted teeth with amalgam fillings and amalgam-contaminated waste, such as trituration capsules and cotton rolls are discharged with the solid waste and, in most instances, are incinerated. Use of disinfectants containing oxidizing substances in dental aspirator kits may contribute to remobilization of mercury and its subsequent release into the environment. Nevertheless, dental mercury contamination is only a small proportion of terrestrial mercury (3-4 per cent), which is quite insignificant compared with industrial pollution and combustion of fossil fuels by vehicles. The environmental impact of dental mercury is mainly due to the poor management of dental amalgam waste. Proper collection of mercury-contaminated solid waste prevents the release of mercury vapour during combustion. In addition, the use of amalgam separating devices reduces the amount of amalgam-contaminated water released from dental clinics.

  5. Amalgam Contact Hypersensitivity Lesion: An Unusual Presentation ...

    African Journals Online (AJOL)

    Contact allergic reactions due to hypersensitivity to dental materials in professionals and ... Keywords: Amalgam, Amalgam contact hypersensitivity lesion, Lichenoid reaction, Oral mucosa ... was associated with mild burning sensation. The patient did ... OLLD in which oral and/or skin lesions appear in temporal association ...

  6. Making High-Tensile-Strength Amalgam Components

    Science.gov (United States)

    Grugel, Richard

    2008-01-01

    Structural components made of amalgams can be made to have tensile strengths much greater than previously known to be possible. Amalgams, perhaps best known for their use in dental fillings, have several useful attributes, including room-temperature fabrication, corrosion resistance, dimensional stability, and high compressive strength. However, the range of applications of amalgams has been limited by their very small tensile strengths. Now, it has been discovered that the tensile strength of an amalgam depends critically on the sizes and shapes of the particles from which it is made and, consequently, the tensile strength can be greatly increased through suitable choice of the particles. Heretofore, the powder particles used to make amalgams have been, variously, in the form of micron-sized spheroids or flakes. The tensile reinforcement contributed by the spheroids and flakes is minimal because fracture paths simply go around these particles. However, if spheroids or flakes are replaced by strands having greater lengths, then tensile reinforcement can be increased significantly. The feasibility of this concept was shown in an experiment in which electrical copper wires, serving as demonstration substitutes for copper powder particles, were triturated with gallium by use of a mortar and pestle and the resulting amalgam was compressed into a mold. The tensile strength of the amalgam specimen was then measured and found to be greater than 10(exp 4) psi (greater than about 69 MPa). Much remains to be done to optimize the properties of amalgams for various applications through suitable choice of starting constituents and modification of the trituration and molding processes. The choice of wire size and composition are expected to be especially important. Perusal of phase diagrams of metal mixtures could give insight that would enable choices of solid and liquid metal constituents. Finally, whereas heretofore, only binary alloys have been considered for amalgams

  7. Dental amalgam: effects of alloy/mercury mixing ratio, uses and waste management

    International Nuclear Information System (INIS)

    Kefi, I.; Maria, A.; Sana, J.; Afreen, J.; Adel, S.; Iftikhar, A.; Yawer, A.; Kaleem, M.

    2011-01-01

    Background: Silver dental amalgam is one of the oldest filling materials used in dentistry. The American Dental Association (ADA) has estimated that billions of amalgam restorations have been placed in patients in the last 150 years. Due to the presence of mercury and mishandling during the filling make it more controversial. The objective of this study was to conduct a survey of the use of different brands and to assess any deviations in practice from the hand mixing manual method of elemental mercury and alloy in a pestle/mortar and encapsulated form. Methods: A questionnaire was sent to 250 of randomly selected dental practitioner in various localities of Karachi. Data was analysed to record the specified brands used along with their powder/liquid (P/L) ratio and the different methods for disposing off mercury in this study. Results: The most commonly used form of dispensing method was hand mixing (57%) and only 30% of the dentists followed the manufacturer instruction for hand mixing ratio. Eighty-seven percent of dental amalgam restoration was performed and 13% removed by the dentist per month and the method of disposing the amalgam wastage that 55%, 25%, and 20% dentists were used the sink, bin and other methods respectively in their dental clinics. Conclusion: Amalgam restoration is still popular filling material in the posterior region of the mouth but we need to create awareness among the dentists who do not follow the ADA specifications. (author)

  8. A Review on Dental Amalgam Corrosion and Its Consequences

    Directory of Open Access Journals (Sweden)

    M Fathi

    2004-02-01

    Full Text Available Dental amalgam is still the most useful restorative material for posterior teeth and has been successfully used for over a century. Dental amalgam has been widely used as a direct filling material due to its favorable mechanical properties as well as low cost and easy placement. However, the mercury it contains raises concerns about its biological toxicity and environmental hazard. Although in use for more than 150 years, dental amalgam has always been suspected more or less vigorously due to its alleged health hazard. Amalgam restorations often tarnish and corrode in oral environment. Corrosion of dental amalgam can cause galvanic action. Ion release as a result of corrosion is most important. Humans are exposed to mercury and other main dental metals via vapor or corrosion products in swallowed saliva and also direct absorption into blood from oral mucosa. During recent decades the use of dental amalgam has been discussed with respect to potential toxic effects of mercury components. In this article, the mechanisms of dental amalgam corrosion are described and results of researches are reviewed. It finally covers the corrosion of amalgams since this is the means by which metals, including mercury, can be released within oral cavity. Keywords: Dental amalgam, Amalgam corrosion, Biocompatibility, Mercury release, Amalgam restoration

  9. Longevity of dental amalgam in comparison to composite materials

    Directory of Open Access Journals (Sweden)

    Windisch, Friederike

    2008-11-01

    Full Text Available Health political background: Caries is one of the most prevalent diseases worldwide. For (direct restaurations of carious lesions, tooth-coloured composite materials are increasingly used. The compulsory health insurance pays for composite fillings in front teeth; in posterior teeth, patients have to bear the extra cost. Scientific background: Amalgam is an alloy of mercury and other metals and has been used in dentistry for more than one hundred and fifty years. Composites consist of a resin matrix and chemically bonded fillers. They have been used for about fifty years in front teeth. Amalgam has a long longevity; the further development of composites has also shown improvements regarding their longevity. Research questions: This HTA-report aims to evaluate the longevity (failure rate, median survival time (MST, median age of direct amalgam fillings in comparison to direct composite fillings in permanent teeth from a medical and economical perspective and discusses the ethical, legal and social aspects of using these filling materials. Methods: The systematic literature search yielded a total of 1,149 abstracts. After a two-step selection process based on defined criteria 25 publications remained to be assessed. Results: The medical studies report a longer longevity for amalgam fillings than for composite fillings. However, the results of these studies show a large heterogeneity. No publication on the costs or the cost-effectiveness of amalgam and composite fillings exists for Germany. The economic analyses (NL, SWE, GB report higher costs for composite fillings when longevity is assumed equal (for an observation period of five years or longer for amalgam compared to composite fillings. These higher costs are due to the higher complexity of placing composite fillings. Discussion: Due to different study designs and insufficient documentation of study details, a comparison of different studies on longevity of direct amalgam and composite

  10. Does Magnetic Resonance Imaging Affect the Microleakage of Amalgam Restorations?

    International Nuclear Information System (INIS)

    Akgun, Ozlem Marti; Polat, Gunseli Guven; Turan Illca, Ahmet; Yildirim, Ceren; Demir, Pervin; Basak, Feridun

    2014-01-01

    The effect of MRI on microleakage of amalgam restorations is an important health issue that should be considered. If MRI application causes increase of microleakage, amalgam fillings should be reassessed after MRI and replaced if necessary. The aim of this study is to compare the effect of magnetic resonance imaging (MRI) on microleakage of class II bonded amalgam versus classical amalgam restorations. Class II cavities (3 mm width × 1.5 mm depth) with gingival margins ending 1 mm below the cementoenamel junction (CEJ) were prepared in 40 permanent molar teeth. The teeth were randomly divided into four groups. Cavities in the first and second groups were restored with dentin adhesive and amalgam (bonded amalgam), and those in the third and fourth groups with amalgam only. MRI was performed with the teeth specimens from the first and third groups. All specimens were then thermocycled at 5° to 55° C with a 30-second dwell time for 1000 cycles. The samples were then immersed in 0.5% methylene blue dye for 24 hours and sectioned longitudinally. Dye penetration at the occlusal and gingival margins was quantified by 15× stereomicroscopy. IBM SPSS Statistics ver. 21.0 (IBM Corp., Released 2012., IBM SPSS Statistics for Windows, Armonk, NY: IBM Corp.) and MS-Excel 2007 programs were used for statistical analyses and calculations. “nparLD” module was used for F2-LD-F1 design analysis at R program. P<0.05 was considered statistically significant. In teeth with amalgam filling, there were no significant differences of occlusal and gingival surface microleakage after MRI exposure. Occlusal and gingival surface microleakages were also similar with and without MRI in teeth with bonded amalgam filling. The results of this study suggest that MRI does not increase microleakage of amalgam restorations

  11. Nordic dentists' opinions on the safety of amalgam and other dental restorative materials.

    Science.gov (United States)

    Widström, E; Haugejorden, O; Sundberg, H; Birn, H

    1993-08-01

    The safety of amalgam and other restorative materials has caused concern among dental patients in recent years. The aim of this study was to obtain information on dentists' perceived competence in handling different filling materials and their opinions on the safety of these. A random sample of practising dentists in Denmark, Finland, Norway, and Sweden received a mail questionnaire in spring 1990. Answers were received from 1732 dentists (65%). The study showed that the respondents believed that their theoretic knowledge and clinical skills were generally at a high level regarding restorative materials. The risks of the side-effects of gold, ceramic materials, and glass ionomer were considered to be low by about 90% of the respondents. Amalgam was considered to be significantly more hazardous by the Swedish respondents than the others. Interestingly, composite was considered to be associated with a high risk of side-effects by about half of the dentists in all Nordic countries. The dentists' opinions were not found to be greatly influenced by their sex, age, or place of residence but rather by their country and service sector. Against the background of the present lack of scientific evidence on the hazardousness of amalgam or other restorative materials for patients' general health, these findings indicate that dentists are influenced by discussions in the mass media about dental treatment and materials and, of course, by the guidelines given by the health authorities in their own countries. Few dentists were shown to be concerned about occupational risks associated with the use of amalgam, and they had not had their own amalgam fillings replaced.(ABSTRACT TRUNCATED AT 250 WORDS)

  12. Dental amalgam and mercury vapor release.

    Science.gov (United States)

    Osborne, J W

    1992-09-01

    Dental diseases are among the most common ailments, and dentists in the United States spend over 50% of their time in dental practice rebuilding carious, malformed, and traumatically injured teeth. It is logical, therefore, that the majority of the dental school curriculum is devoted to the diagnosis, prevention, and treatment of teeth with anomalies. Dentists have several choices of materials they can use to accomplish the task of rebuilding teeth. Besides amalgam, they have ceramic materials, resin composites, base-metal and noble casting alloys, and glass-ionomer cements to use to restore the posterior dentition. Each of these restorative materials has advantages and disadvantages, and the clinical judgment as to when a particular material should be used is given a high priority in dental education. Amalgam is the most widely used of these restorative materials, with 92% of dentists listing it as the material of choice in the posterior of the mouth (Clinical Research Associates, 1990). Dentists have been placing amalgams for over 150 years in the US. They placed 150 million last year, which represents over 75 tons of amalgam alloy. The reasons that dentists use this restorative material so frequently are its durability, ease of manipulation, and low cost. Numerous clinical studies have been conducted on the serviceability of amalgam. Most of these have been on the old, low-copper alloys, and results indicate that they last from 8 to 15 years (Bailit et al., 1979; Osborne et al., 1980; Qvist et al., 1986). In the past 20 years, vast improvements have been made in amalgams with the development of the high-copper systems.(ABSTRACT TRUNCATED AT 250 WORDS)

  13. Gastrointestinal and in vitro release of copper, cadmium, indium, mercury and zinc from conventional and copper-rich amalgams

    International Nuclear Information System (INIS)

    Brune, D.; Gjerdet, N.; Paulsen, G.

    1983-01-01

    Particles of a conventional lathe-cut, a spherical non-gamma 2 and a copper amalgam have been gastrointestinally administered to rats for the purpose of evaluation of the dissolution resistance. The animals were sacrificed after 20 hrs. The contents of copper, cadmium, indium, mercury and zinc in kidney, liver, lung or blood were measured using nuclear tracer techniques. From a copper amalgam an extreme release of copper was demonstrated. This study simulates the clinical conditions of elemental release from swallowed amalgam particles after amalgam insertion or after removal of old amalgam fillings. Specimens of the same types of amalgams were also exposed to artificial saliva for a period of 10 days. The amounts of copper and mercury released were measured with flame and flameless atomic absorption spectrophotometry respectively. The levels of copper and mercury released from the copper amalgam were approximately 50 times those of the two other amalgam types studied. (author)

  14. Amalgams and χ-Boundedness

    DEFF Research Database (Denmark)

    Penev, Irena

    2017-01-01

    , clique-cutsets, and amalgams together preserve χ-boundedness. More precisely, we show that if G and G∗ are hereditary classes of graphs such that G is χ-bounded, and such that every graph in G∗ either belongs to G or admits a proper homogeneous set, a clique-cutset, or an amalgam, then the class G∗ is χ...

  15. [The future of dental amalgam

    NARCIS (Netherlands)

    Opdam, N.J.M.

    2005-01-01

    This paper is a comment on 'The enigma of dental amalgam' by Carl Leinfelder published in 2004 in the Journal of Esthetic and Restorative Dentistry. In that paper a warning is stated against a too abrupt change from amalgam towards resin composite, because this will bring a lot of clinical problems

  16. A Safe Protocol for Amalgam Removal

    Directory of Open Access Journals (Sweden)

    Dana G. Colson

    2012-01-01

    Full Text Available Today's environment has different impacts on our body than previous generations. Heavy metals are a growing concern in medicine. Doctors and individuals request the removal of their amalgam (silver mercury restorations due to the high mercury content. A safe protocol to replace the silver mercury filling will ensure that there is minimal if any absorption of materials while being removed. Strong alternative white composite and lab-processed materials are available today to create a healthy and functioning mouth. Preparation of the patient prior to the procedure and after treatment is vital to establish the excretion of the mercury from the body.

  17. Patients’ experiences of changes in health complaints before, during, and after removal of dental amalgam

    Directory of Open Access Journals (Sweden)

    Therese T. Sjursen

    2015-06-01

    Full Text Available In this article, we explore how patients with health complaints attributed to dental amalgam experienced and gave meaning to changes in health complaints before, during, and after removal of all amalgam fillings. We conducted semistructured qualitative interviews with 12 participants from the treatment group in a Norwegian amalgam removal trial. Interviews took place within a couple months of the final follow-up 5 years after amalgam removal. Using the NVivo9 software, we conducted an explorative and reflective thematic analysis and identified the following themes: Something is not working: betrayed by the body, You are out there on your own, Not being sure of the importance of amalgam removal, The relief experienced after amalgam removal, and To accept, to give up, or to continue the search. We discuss the findings in the context of patients’ assigning meaning to illness experiences.

  18. Tatuagem extensa por amálgama em mucosa gêngivo-alveolar Extensive amalgam tattoo on the alveolar-gingival mucosa

    Directory of Open Access Journals (Sweden)

    Vivian C Galletta

    2011-10-01

    Full Text Available Tatuagens por amálgama são lesões pigmentadas, exógenas, de frequente ocorrência na mucosa bucal, que resultam da introdução acidental de partículas de amálgama nos tecidos moles. O diagnóstico da tatuagem por amálgama é simples, geralmente, baseado em achados clínicos, complementado pela história recente ou pregressa de remoção de restauração por amálgama. Radiografias intraorais podem ser úteis na detecção de radiopacidade, associadas à partícula de amálgama. Nos casos em que as tatuagens por amálgama não permitem diferenciação de outras lesões melanocíticas, o exame histopatológico deve ser realizado. Os autores relatam à ocorrência de lesão extensa por tatuagem de amálgama com confirmação histopatológica.Amalgam tattoos are common exogenous pigmented lesions of the oral mucosa occurring mainly by inadvertent placement of amalgam particles into soft tissues. The diagnosis of amalgam tattoo is simple, usually based on clinical findings associated with presence or history of amalgam fillings removal. Intraoral X-rays may be helpful in detecting amalgam-related radiopacity. In cases where amalgam tattoo cannot be differentiated from other causes of oral pigmentation, a biopsy should be performed. This article deals with an extensive amalgam tattoo lesion which required a biopsy for a definitive diagnosis.

  19. A dose-effect analysis of children's exposure to dental amalgam and neuropsychological function: the New England Children's Amalgam Trial.

    Science.gov (United States)

    Bellinger, David C; Trachtenberg, Felicia; Daniel, David; Zhang, Annie; Tavares, Mary A; McKinlay, Sonja

    2007-09-01

    The New England Children's Amalgam Trial (NECAT) was a five-year randomized trial of 534 6- to 10-year-old children that compared the neuropsychological outcomes of those whose caries were restored using dental amalgam with the outcomes of those those whose caries were restored using mercury-free resin-based composite. The primary intention-to-treat analyses did not reveal significant differences between the treatment groups on the primary or secondary outcomes of the administered psychological tests: Full-Scale IQ score on the Wechsler Intelligence Scale for Children-Third Edition, General Memory Index of the Wide Range Assessment of Memory and Learning, and Visual-Motor Composite of the Wide Range Assessment of Visual Motor Abilities. To determine whether treatment group assignment, a dichotomous measure of exposure, was sufficiently sensitive to detect associations between mercury exposure and these outcomes, the authors conducted analyses to evaluate the associations between the primary and secondary outcomes and two continuously distributed indexes of potential exposure, surface-years of amalgam and urinary mercury excretion. Neither index of mercury exposure was significantly associated with any of the three outcomes. The authors found no evidence that exposure to mercury from dental amalgam was associated with any adverse neuropsychological effects over the five-year period after placement of amalgam restorations. Analyses of the outcomes of the NECAT study indicate that use of dental amalgam was not associated with an increase in children's risk of experiencing neuropsychological dysfunction.

  20. Evaluation of the dental structure loss produced during maintenance and replacement of occlusal amalgam restorations

    Directory of Open Access Journals (Sweden)

    Fernanda Sardenberg

    2008-09-01

    Full Text Available The aim of this in vitro study was to evaluate four different approaches to the decision of changing or not defective amalgam restorations in first primary molar teeth concerning the loss of dental structure. Ditched amalgam restorations (n = 11 were submitted to four different treatments, as follows: Control group - polishing and finishing of the restorations were carried out; Amalgam group - the ditched amalgam restorations were replaced by new amalgam restorations; Composite resin group - the initial amalgam restorations were replaced by composite resin restorations; Flowable resin group - the ditching around the amalgam restorations was filled with flowable resin. Images of the sectioned teeth were made and the area of the cavities before and after the procedures was determined by image analysis software to assess structural loss. The data were submitted to ANOVA complemented by the Student Newman Keuls test (p < 0.05. The cavities in all the groups presented significantly greater areas after the procedures. However, the amalgam group showed more substantial dental loss. The other three groups presented no statistically significant difference in dental structure loss after the re-treatments. Thus, replacing ditched amalgam restorations by other similar restorations resulted in a significant dental structure loss while maintaining them or replacing them by resin restorations did not result in significant loss.

  1. A comparison of glass cermet cement and amalgam restorations in primary molars.

    Science.gov (United States)

    Hickel, R; Voss, A

    1990-01-01

    The aim of this clinical study was to compare the efficacy of GCC with amalgam as a filling material in primary molars. Two hundred fifteen restorations were placed in the first and second primary molars of seventy-four patients, ranging in age from four to ten years. The overall failure rate of amalgam is lower than that of GCC, but not significantly different. In older children, amalgam has greater advantages. An advantage of GCC is the short time required to fill the cavity. This might be an important factor in young and/or difficult children. In these cases amalgam cannot be placed under optimal conditions and, therefore, the results are less satisfactory. GCC is a viable alternative filling material.

  2. Rank gradient and p-gradient of amalgamated free products and HNN extensions

    OpenAIRE

    Pappas, Nathaniel

    2013-01-01

    We calculate the rank gradient and p-gradient of free products, free products with amalgamation over an amenable subgroup, and HNN extensions with an amenable associated subgroup. The notion of cost is used to compute the rank gradient of amalgamated free products and HNN extensions. For the p-gradient the Kurosh subgroup theorems for amalgamated free products and HNN extensions will be used.

  3. Genotoxic effects of silver amalgam and composite restorations: Micronuclei-Based cohort and case–control study in oral exfoliated cells

    Directory of Open Access Journals (Sweden)

    S Jeslin Mary

    2018-01-01

    Full Text Available Context: A huge number of people carry dental fillings which contain either mercury-based amalgam and/or the recently introduced methacrylate-based resins. It has been shown that both these materials are known to be leached into the oral cavity and induce genotoxic alterations in the buccal mucosal cells. Because of its low cost and ease of manipulation, dental amalgam is still widely used as a restorative material in developing countries. The health risks associated with the components of this restorative material has always been a matter of concern. The present study was designed to assess the frequency of micronuclei (MN in oral mucosal cells as it is a promising tool for studying the genotoxic effect of clastogenic agents on them. Aims: The aim of this study is to evaluate the genotoxic effects of silver amalgam and composite restorations by measuring the mean number of MN in oral exfoliated cells. Materials and Methods: The present study was a prospective cohort study which includes a study group consisting of 110 participants. The study sample was equally divided into 55 participants requiring only amalgam restoration and 55 participants requiring only composite restoration in any permanent molar teeth. The same participants before the restoration formed the control group. Smears were obtained from each patient before and 10 days after restoration and were stained with DNA-specific Feulgen stain. The number of cells containing MN out of 500 cells were counted and recorded. After the evaluation of the slides, the results were compiled and subjected to statistical analysis. Results: There was a statistically significant (P < 0.01 variation in the mean number of MN after the restoration in both amalgam (5.41 ± 1.25 and composite (2.83 ± 0.85 restorations when compared to before the restoration. However, the mean number of MN in composite restoration was significantly less when compared to amalgam restoration. There was also a statistically

  4. Biologic assessment of copper-containing amalgams.

    Science.gov (United States)

    Mjor, I A; Eriksen, H M; Haugen, E; Skogedal, O

    1977-12-01

    In order to reduce creep and avoid marginal fractures in amalgam restorations, new alloys containing higher proportions of copper have been introduced. Fillings of these materials were placed in cavities prepared in the deciduous teeth of monkeys or placed in polyethylene tubes and implanted subcutaneously in rats. Conventional silver/tin alloys and zinc oxide eugenol cement were used as reference materials. Despite limitations due to the varying depths of cavities and the small number of animals involved it was concluded that the high copper alloys caused more severe pulp damage than the other materials studied. In the implantation studies many of the high copper specimens were exfoliated before the end of the experimental period. It is concluded that in deep cavities these materials require the use of a non-toxic base or lining material although as they are commonly used in young children's teeth the placement of linings and the isolation of the cavity pose problems.

  5. 21 CFR 872.3070 - Dental amalgam, mercury, and amalgam alloy.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Dental amalgam, mercury, and amalgam alloy. 872... SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3070 Dental amalgam, mercury... elemental mercury, supplied as a liquid in bulk, sachet, or predosed capsule form, and amalgam alloy...

  6. Comprehension of amalgamation for future digital society

    International Nuclear Information System (INIS)

    Lee, Byeong Uk

    2010-08-01

    This book deals with understanding of amalgamation for future digital society, which describes outline of amalgamation, ubiquitous environment, cognitive science I such as psychology and neurology, cognitive science II like philosophy, linguistics and anthropology, an automatic machine, evolution theory and amalgamation, brain science and consciousness, mind and software and creativity and art. Each chapter has introduction, composition, related science, function and models.

  7. Penetration of amalgam constituents into dentine

    NARCIS (Netherlands)

    Scholtanus, Johannes D.; Ozcan, Mutlu; Huysmans, Marie-Charlotte D. N. J. M.

    Objectives: Amalgam restorations are replaced by adhesively placed composite resin restorations at an increasing rate. After the removal of amalgam dentine often shows marked dark discoloration that is attributed to the penetration of corrosion products from overlying amalgams. it is questioned

  8. Penetration of amalgam constituents into dentine.

    NARCIS (Netherlands)

    Scholtanus, J.D.; Ozcan, M.; Huysmans, M.C.D.N.J.M.

    2009-01-01

    OBJECTIVES: Amalgam restorations are replaced by adhesively placed composite resin restorations at an increasing rate. After the removal of amalgam dentine often shows marked dark discoloration that is attributed to the penetration of corrosion products from overlying amalgams. It is questioned

  9. Comprehension of amalgamation for future digital society

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Byeong Uk

    2010-08-15

    This book deals with understanding of amalgamation for future digital society, which describes outline of amalgamation, ubiquitous environment, cognitive science I such as psychology and neurology, cognitive science II like philosophy, linguistics and anthropology, an automatic machine, evolution theory and amalgamation, brain science and consciousness, mind and software and creativity and art. Each chapter has introduction, composition, related science, function and models.

  10. Conditioning of spent mercury by amalgamation

    International Nuclear Information System (INIS)

    Yim, S. P.; Shon, J. S.; An, B. G.; Lee, H. J.; Lee, J. W.; Ji, C. G.; Kim, S. H.; Yoon, J. H.; Yang, M. S.

    2002-01-01

    Solidification by amalgamation was performed to immobilize and stabilize the liquid spent mercury. First, the appropriate metal and alloy which can convert liquid mercury into a solid form of amalgam were selected through initial tests. The amalgam form, formulated in optimum composition, was characterized and subjected to performance tests including compressive strength, water immersion, leachability and initial vaporization rate to evaluate mechanical integrity, durability and leaching properties. Finally, bench scale amalgamation trial was conducted with about 1 kg of spent mercury to verify the feasibility of amalgamation method

  11. Dental amalgam and cognitive function in older women: findings from the Nun Study.

    Science.gov (United States)

    Saxe, S R; Snowdon, D A; Wekstein, M W; Henry, R G; Grant, F T; Donegan, S J; Wekstein, D R

    1995-11-01

    The authors determined the number and surface area of occlusal dental amalgams in a group of 129 Roman Catholic sisters who were 75 to 102 years of age. Findings from this study of women with relatively homogeneous adult lifestyles and environments suggest that existing amalgams are not associated with lower performance on eight different tests of cognitive function.

  12. Daya Antibakteri Bahan Tumpat Amalgam dan Resin Komposit Berfluor Terhadap Bakteri Streptococcus Mutans Serotipe KPSK2

    Directory of Open Access Journals (Sweden)

    Dewa Ayu Nyoman Putri Artiningsih

    2015-09-01

    Full Text Available This research was carried out to study the difference in the antibacterial capacity of two kinds of filling materials, namely amalgam and composite resin, on S. mutans KPSK2 bacteria with different times of treatment. In total, 48 amalgam and composite resin samples each were prepared and then divided into four groups of treatment. Of each group, 6 samples were used to count the number of bacterial colonies and 6 samples to count the right obstacle zone. The results show that the best antibacterial capacity of composite resin occurred within one week, while for amalgam the best performance appears within one day. The antibacterial capacity of fluorine containing composites is stronger than that of amalgam for a time of 1 to 2 weeks.

  13. Amalgam-chromatographic separation of magnesium isotopes

    International Nuclear Information System (INIS)

    Klinskij, G.D.; Levkin, A.V.; Ivanov, S.A.

    1990-01-01

    Separation of magnesium isotopes within Mg(Hg)-MgI 2 system (in dimethylformamide) is conducted under amalgam-chromatographic conditions. Separation maximal degree, that is (1.09), for 24 Mg and 26 Mg and separation coefficient (α = 1.0089±0.006) are determined. Light isotopes are found to concentrate in the amalgam. Technique of thermal conversion of flows within amalgam-dimethylformamide system is suggested on the basis of reversible reaction of Ca-Mg element exchange

  14. BI-AMALGAMATION OF SMALL WEAK GLOBAL DIMENSION

    OpenAIRE

    Tamekkante, Mohammed; Bouba, El Mehdi

    2017-01-01

    In this paper, we characterize the bi-Amalgamations of small weakglobal dimension. The new results compare to previous works carried on varioussettings of duplications and amalgamations, and capitalize on recent resultson bi-amalgamations

  15. Properties of amalgams made from lathe-cut, high Cu amalgam alloys.

    Science.gov (United States)

    Espevik, S

    1980-01-01

    Two alloys for dental amalgams made from lathe-cut powder with high Cu content have been developed. The alloys have been characterized with respect to physical properties and microstructure. The strongest amalgam exhibited minimal dimensional changes during setting and had low flow and creep values. It had the highest Cu content of the two amalgams investigated and no gamma 2 phase. The epsilon and eta' phases may dispersion-strenthen the amalgam which in compressive strength was comparable to the strongest amalgams available. A new mechanism for gamma 2 disappearance is suggested where Cu replaces Hg directly in the gamma 2 phase thus forming the eta' phase.

  16. The problem of motivating teaching staff in a complex amalgamation.

    Science.gov (United States)

    Kenrick, M A

    1993-09-01

    This paper addresses some of the problems brought about by the merger of a number of schools of nursing into a new complex amalgamation. A very real concern in the new colleges of nursing and midwifery in the United Kingdom is the effect of amalgamation on management systems and staff morale. The main focus of this paper is the motivation of staff during this time of change. There is currently a lack of security amongst staff and in many instances the personal job satisfaction of nurse teachers and managers of nurse education has been reduced, which has made the task of motivating staff difficult. Hence, two major theories of motivation and the implications of these theories for managers of nurse education are discussed. The criteria used for the selection of managers within the new colleges, leadership styles and organizational structures are reviewed. The amalgamations have brought about affiliation with higher-education institutions. Some problems associated with these mergers and the effects on the motivation of staff both within the higher-education institutions and the nursing colleges are outlined. Strategies for overcoming some of the problems are proposed including job enlargement, job enrichment, potential achievement rewards and the use of individual performance reviews which may be useful for assessing the ability of all staff, including managers, in the new amalgamations.

  17. Prenatal exposure to dental amalgam: evidence from the Seychelles Child Development Study main cohort.

    Science.gov (United States)

    Watson, Gene E; Lynch, Miranda; Myers, Gary J; Shamlaye, Conrad F; Thurston, Sally W; Zareba, Grazyna; Clarkson, Thomas W; Davidson, Philip W

    2011-11-01

    Dental amalgams contain approximately 50 percent metallic mercury and emit mercury vapor during the life of the restoration. Controversy surrounds whether fetal exposure to mercury vapor resulting from maternal dental amalgam restorations has neurodevelopmental consequences. The authors determined maternal amalgam restoration status during gestation (prenatal exposure to mercury vapor [Hg(0)]) retrospectively in 587 mother-child pairs enrolled in the Seychelles Child Development Study, a prospective longitudinal cohort study of the effects of prenatal and recent postnatal methylmercury (MeHg) exposure on neurodevelopment. They examined covariate-adjusted associations between prenatal maternal amalgam restoration status and the results of six age-appropriate neurodevelopmental tests administered at age 66 months. The authors fit the models without and with adjustment for prenatal and recent postnatal MeHg exposure metrics. The mean number of maternal amalgam restorations present during gestation was 5.1 surfaces (range, 1-22) in the 42.4 percent of mothers who had amalgam restorations. The authors found no significant adverse associations between the number of amalgam surfaces present during gestation and any of the six outcomes, with or without adjustment for prenatal and postnatal MeHg exposure. Results of analyses with the secondary metric, prenatal amalgam occlusal point scores, showed an adverse association in boys only on a letter- and word-identification subtest of a frequently used test of scholastic achievement, whereas girls scored better on several other tests with increasing exposure. This study's results provide no support for the hypothesis that prenatal Hg(0) exposure arising from maternal dental amalgam restorations results in neurobehavioral consequences in the child. These findings require confirmation from a prospective study of coexposure to MeHg and Hg(0).

  18. Marginal microfiltration in amalgam restorations. Review

    OpenAIRE

    Lahoud Salem, Víctor

    2014-01-01

    The present articule is review references from phenomenon of microfiltration in restorations with amalgam and yours consecuents in changes of color in the interface tooth-restorations, margin deterioted , sensitivity dentinarea postoperate, caries secondary and pulp inflamation. Besides naming the mechanicals for to reduce microfiltration, and yours effects for use of sealers dentinaries representation for the varnish cavitys and adhesive systens Conclusive indicate wath the amalgam is the ma...

  19. Mechanical behaviour of dental composite filling materials using digital holography

    OpenAIRE

    Monteiro, J.M.; Lopes, H.; Vaz, M.A.P.; Campos, J.C. Reis

    2010-01-01

    One of the most common clinical problems in dentistry is tooth decay. Among the dental filling materials used to repair tooth structure that has been destroyed by decay are dental amalgam and composite materials based on acrylics. Dental amalgam has been used by dentists for the past 150 years as a dental restorative material due to its low cost, ease of application, strength, durability, and bacteriostatic effects. However its safety as a filling material has been questioned due to th...

  20. Neurodevelopmental outcomes at 5 years in children exposed prenatally to maternal dental amalgam: the Seychelles Child Development Nutrition Study.

    Science.gov (United States)

    Watson, Gene E; van Wijngaarden, Edwin; Love, Tanzy M T; McSorley, Emeir M; Bonham, Maxine P; Mulhern, Maria S; Yeates, Alison J; Davidson, Philip W; Shamlaye, Conrad F; Strain, J J; Thurston, Sally W; Harrington, Donald; Zareba, Grazyna; Wallace, Julie M W; Myers, Gary J

    2013-01-01

    Limited human data are available to assess the association between prenatal mercury vapor (Hg⁰)) exposure from maternal dental amalgam restorations and neurodevelopment of children. We evaluated the association between maternal dental amalgam status during gestation and children's neurodevelopmental outcomes at 5 years in the Seychelles Child Development Nutrition Study (SCDNS). Maternal amalgam status was determined prospectively in a longitudinal cohort study examining the associations of prenatal exposure to nutrients and methylmercury (MeHg) with neurodevelopment. A total of 236 mother-child pairs initially enrolled in the SCDNS in 2001 were eligible to participate. Maternal amalgam status was measured as number of amalgam surfaces (the primary metric) and number of occlusal points. The neurodevelopmental assessment battery was comprised of age-appropriate tests of cognitive, language, and perceptual functions, and scholastic achievement. Linear regression analysis controlled for MeHg exposure, maternal fatty acid status, and other covariates relevant to child development. Maternal amalgam status evaluation yielded an average of 7.0 surfaces (range 0-28) and 11.0 occlusal points (range 0-40) during pregnancy. Neither the number of maternal amalgam surfaces nor occlusal points were associated with any outcome. Our findings do not provide evidence to support a relationship between prenatal exposure to Hg⁰ from maternal dental amalgam and neurodevelopmental outcomes in children at 5 years of age. © 2013.

  1. “Triple M” Effect: A Proposed Mechanism to Explain Increased Dental Amalgam Microleakage after Exposure to Radiofrequency Electromagnetic Radiation

    Science.gov (United States)

    Mortazavi, Gh.; Mortazavi, S.A.R.; Mehdizadeh, A.R.

    2018-01-01

    A large body of evidence now indicates that the amount of mercury released from dental amalgam fillings can be significantly accelerated by exposure to radiofrequency electromagnetic fields (RF-EMFs) such as common mobile phones and magnetic resonance imaging (MRI). Studies performed on the increased microleakage of dental amalgam restorations after exposure to RF-EMFs have further supported these findings. Although the accelerated microleakage induced by RF-EMFs is clinically significant, the entire mechanisms of this phenomenon are not clearly understood. In this paper, we introduce “Triple M” effect, a new evidence-based theory which can explain the accelerated microleakage of dental amalgam fillings after exposure to different sources of electromagnetic radiation. Based on this theory, there are saliva-filled tiny spaces between amalgam and the tooth. Exposure of the oral cavity to RF-EMFs increases the energy of these small amounts of saliva. Due to the small mass of saliva in these tiny spaces, a small amount of energy will be required for heating. Moreover, reflection of the radiofrequency radiation on the inner walls of the tiny spaces causes interference which in turn produces some “hot spots” in these spaces. Finally, formation of gas bubbles in response to increased temperature and very rapid expansion of these bubbles will accelerate the microleakage of amalgam. Experiments that confirm the validity of this theory are discussed. PMID:29732349

  2. "Triple M" Effect: A Proposed Mechanism to Explain Increased Dental Amalgam Microleakage after Exposure to Radiofrequency Electromagnetic Radiation.

    Science.gov (United States)

    Mortazavi, Gh; Mortazavi, S A R; Mehdizadeh, A R

    2018-03-01

    A large body of evidence now indicates that the amount of mercury released from dental amalgam fillings can be significantly accelerated by exposure to radiofrequency electromagnetic fields (RF-EMFs) such as common mobile phones and magnetic resonance imaging (MRI). Studies performed on the increased microleakage of dental amalgam restorations after exposure to RF-EMFs have further supported these findings. Although the accelerated microleakage induced by RF-EMFs is clinically significant, the entire mechanisms of this phenomenon are not clearly understood. In this paper, we introduce "Triple M" effect, a new evidence-based theory which can explain the accelerated microleakage of dental amalgam fillings after exposure to different sources of electromagnetic radiation. Based on this theory, there are saliva-filled tiny spaces between amalgam and the tooth. Exposure of the oral cavity to RF-EMFs increases the energy of these small amounts of saliva. Due to the small mass of saliva in these tiny spaces, a small amount of energy will be required for heating. Moreover, reflection of the radiofrequency radiation on the inner walls of the tiny spaces causes interference which in turn produces some "hot spots" in these spaces. Finally, formation of gas bubbles in response to increased temperature and very rapid expansion of these bubbles will accelerate the microleakage of amalgam. Experiments that confirm the validity of this theory are discussed.

  3. Mercury release from dental amalgam restorations after magnetic resonance imaging and following mobile phone use

    Energy Technology Data Exchange (ETDEWEB)

    Mortazavi, S M.J., [Shiraz Univ. of Medical Sciences (Iran, Islamic Republic of). School of Paramedical Sciences; Daiee, E; Yazdi, A; Khiabani, K; Kavousi, A [Rafsanjan Univ. of Medical Sciences (Iran, Islamic Republic of). Dentistry School; Vazirinejad, R [Rafsanjan Univ. of Medical Sciences (Iran, Islamic Republic of). School of Medicine, Community Medicine Dept.; Behnejad, B [Rafsanjan Univ. of Medical Sciences (Iran, Islamic Republic of). School of Paramedical Sciences, Radiologic Technology Dept.; Ghasemi, M [Mashad University of Medical Science (Iran, Islamic Republic of). Imam Reza Hospital, Toxicology Laboratory; Mood, M Balali [Mashad Univ. of Medical Science (Iran, Islamic Republic of). Imam Reza Hospital, Medical Toxicology Research Center

    2008-07-01

    Background: Mercury or Hydrargyrum (Hg) is the most non-radioactive toxic element. Dental amalgam is made up of 50% mercury. Exposure to electromagnetic fields of magnetic resonance imaging (MRI) and microwave radiation emitted from mobile phone use may increase the emission of mercury from dental amalgam fillings. It was thus aimed to study the effects of exposure to MRI and mobile phone use on the mercury release from dental amalgam restorations. Materials and Methods: Following approval of the University Medical Ethics Committee and the informed consents of the subjects, two different studies were undertaken. A-MRI: - Thirty patients (27 F, 3 M) aged 18 to 48 years who had been referred to MRI department of Ali-ebn Abitaleb Teaching Hospital and had at least four amalgam restorated teeth, were investigated. Five ml stimulated saliva was collected just before and after MRI. The magnetic flux density was 0.23 T, and the duration of exposure of patients to magnetic field was 30 minutes. B-Mobile phone Use: Fourteen female healthy University students aged 19-23 years, who had not used mobile phones before the study and did not have any previous amalgam restorations but had decays in at least four teeth were investigated. Their urine samples were collected before amalgam restoration, and at days 1, 2, 3 and 4 after restoration. Dental amalgam restoration was performed for all 14 students (2 molars on one side, one class I and one class II restorations with identical volume and surface area of the amalgam fillings). The students randomly divided into two equal groups. The test group students were exposed to microwave radiation emitted from a Nokia 3310 mobile phone (SAR=0.96 W kg{sup -1}) that was operated in talk mode for 15 min every day at days 1-4 after restoration. The other seven female age matched students who served as controls sham exposed to microwave radiation. For each subject, a questionnaire regarding their possible sources of exposure to electromagnetic

  4. Mercury release from dental amalgam restorations after magnetic resonance imaging and following mobile phone use

    International Nuclear Information System (INIS)

    Mortazavi, S.M.J.; Daiee, E.; Yazdi, A.; Khiabani, K.; Kavousi, A.; Vazirinejad, R.; Behnejad, B.; Ghasemi, M.; Mood, M. Balali

    2008-01-01

    Background: Mercury or Hydrargyrum (Hg) is the most non-radioactive toxic element. Dental amalgam is made up of 50% mercury. Exposure to electromagnetic fields of magnetic resonance imaging (MRI) and microwave radiation emitted from mobile phone use may increase the emission of mercury from dental amalgam fillings. It was thus aimed to study the effects of exposure to MRI and mobile phone use on the mercury release from dental amalgam restorations. Materials and Methods: Following approval of the University Medical Ethics Committee and the informed consents of the subjects, two different studies were undertaken. A-MRI: - Thirty patients (27 F, 3 M) aged 18 to 48 years who had been referred to MRI department of Ali-ebn Abitaleb Teaching Hospital and had at least four amalgam restorated teeth, were investigated. Five ml stimulated saliva was collected just before and after MRI. The magnetic flux density was 0.23 T, and the duration of exposure of patients to magnetic field was 30 minutes. B-Mobile phone Use: Fourteen female healthy University students aged 19-23 years, who had not used mobile phones before the study and did not have any previous amalgam restorations but had decays in at least four teeth were investigated. Their urine samples were collected before amalgam restoration, and at days 1, 2, 3 and 4 after restoration. Dental amalgam restoration was performed for all 14 students (2 molars on one side, one class I and one class II restorations with identical volume and surface area of the amalgam fillings). The students randomly divided into two equal groups. The test group students were exposed to microwave radiation emitted from a Nokia 3310 mobile phone (SAR=0.96 W kg -1 ) that was operated in talk mode for 15 min every day at days 1-4 after restoration. The other seven female age matched students who served as controls sham exposed to microwave radiation. For each subject, a questionnaire regarding their possible sources of exposure to electromagnetic

  5. The Changes in Dentists' Perception and Patient's Acceptance on Amalgam Restoration in Kurdistan-Iraq: A Questionnaire-based Cross-Sectional Study.

    Science.gov (United States)

    Faraj, Bestoon Mohammad; Mohammad, Hawzhen Masoud; Mohammad, Kale Masoud

    2015-04-01

    There has been considerable controversy concerning the health risks and benefits of utilizing mercury-containing amalgam. Across the developing countries, a reduction in the use of dental amalgam in oral health care provision is expected. Assessment of dentists' and patient's attitude of dental amalgam regarding attractiveness, perceived health, and treatment preferences in Kurdistan, Iraq. A 4-page questionnaire comprised two parts, specific for dentist and patient were structured and delivered to each dentist oneself. Both open-ended and close-ended questions about the treatment needs of patients, uses of amalgam and its alternative, the properties and usefulness of different materials. Patient's acceptance was assessed by means of structured questionnaire prepared based on commonly asked questions from routinely daily practice. Questions on the type of filling material in their mouth, previous knowledge of mercury in dental amalgam and disappointment due to mercury hazard and toxicity. They were to indicate their acceptance with filling their cavities by dental amalgam with or without prior information about its mercury content. This part was also accomplished by the dentists participated in this survey. Out of 185 dentists shared, only 39 (21.1%) indicated that amalgam presents no harm for the dentists and patients. While majority of dentists 85 (45.9%) were uncertain about this issue. Amalgam was selected most often 107 (57.8%) as the material of choice for restoring posterior teeth. About 94(50.8%) and 85(45.9%) of the practitioners primarily used glass ionomer/resin-reinforced glass ionomer and composite, respectively. Among 1850 patients received treatment, only 450 (24.32%) claimed to have heard about adverse reactions to dental amalgams. Those who believed it to be safe were 200 (10.82%).Acceptance towards amalgam was 62%. While amalgam was the most common material used for posterior restorations, direct tooth-coloured restorative materials were also

  6. Bi-amalgamations subject to the arithmetical property

    OpenAIRE

    Kabbaj, S.; Mahdou, N.; Moutui, M. A. S.

    2016-01-01

    This paper establishes necessary and sufficient conditions for a bi-amalgamation to inherit the arithmetical property, with applications on the weak global dimension and transfer of the semihereditary property. The new results compare to previous works carried on various settings of duplications and amalgamations, and capitalize on recent results on bi-amalgamations. All results are backed with new and illustrative examples arising as bi-amalgamations.

  7. Amalgam Contact Hypersensitivity Lesion: An Unusual Presentation ...

    African Journals Online (AJOL)

    of electromagnetic fields (e.g. Wi‑Fi, mobile phones and mobile base stations) in intensifying the release of mercury from dental amalgam restorations. Over the past years, our laboratory has focused on studying the health effects of exposure to some common and/or occupational sources of electromagnetic fields such as ...

  8. Boundedness of positive operators on weighted amalgams

    Directory of Open Access Journals (Sweden)

    Aguilar Cañestro María Isabel

    2011-01-01

    Full Text Available Abstract In this article, we characterize the pairs (u, v of positive measurable functions such that T maps the weighted amalgam in (Lp (u, ℓ q for all , where T belongs to a class of positive operators which includes Hardy operators, maximal operators, and fractional integrals. 2000 Mathematics Subject Classification 26D10, 26D15 (42B35

  9. Reference Electrodes Based on Solid Amalgams

    Czech Academy of Sciences Publication Activity Database

    Josypčuk, Bohdan; Novotný, Ladislav

    2004-01-01

    Roč. 16, č. 3 (2004), s. 238-241 ISSN 1040-0397 Grant - others:GIT(AR) 101/02/U111/CZ Institutional research plan: CEZ:AV0Z4040901 Keywords : solid amalgam * reference electrode * voltammetry Subject RIV: CG - Electrochemistry Impact factor: 2.038, year: 2004

  10. Bond strength of resin composite to differently conditioned amalgam

    NARCIS (Netherlands)

    Ozcan, M; Vallittu, PK; Huysmans, MC; Kalk, W; Vahlberg, T

    Bulk fracture of teeth, where a part of the amalgam restoration and/or the cusp is fractured, is a common clinical problem. The aim of this study was to evaluate the effect of different surface conditioning methods on the shear bond strength of a hybrid resin composite to fresh amalgam. Amalgams (N

  11. The association between arterial stiffness and left ventricular filling pressure in an apparently healthy Korean population

    Directory of Open Access Journals (Sweden)

    Kim Hack-Lyoung

    2013-01-01

    Full Text Available Abstract Background The aim of this study is to investigate the association between arterial stiffness and left ventricular filling pressure in an apparently healthy Korean population. Methods A total of 115 healthy subjects without known cardiovascular risk factors or overt heart disease who underwent both transthoracic echocardiography and brachial-ankle pulse wave velocity (baPWV measurement at the same day during their routine check-ups were analyzed. Results The mean age of study subjects was 52.8 ± 8.4 years, and 78 (67.8% were men. The mean baPWV value was 1,325 ± 185 cm/s. Study subjects were divided into 3 groups according to E/E’ value: subjects with E/E’ p β = 0.371, p after controlling confounders including age, sex and body mass index. In receiver-operating characteristic (ROC curve analysis, the sensitivity and specificity for detection of E/E’ ≥ 10 were 78.6% and 59.8%, respectively with mean baPWV of 1,282 cm/s as the cut off value. The discriminatory capacity for predicting E/E’ ≥ 10 was improved from an area under the ROC curve of 0.646 with age alone to 0.734 when baPWV was added (p Conclusions There is a significant association between baPWV and E/E’ in an apparently healthy Korean population. BaPWV is useful as a simple and non-invasive method for early detection of increased LV filling pressure among these people.

  12. Determination of association constants between steroid compounds and albumins by partial-filling ACE.

    Science.gov (United States)

    Amundsen, Lotta K; Sirén, Heli

    2007-10-01

    ACE is a popular technique for evaluating association constants between drugs and proteins. However, ACE has not previously been applied to study the association between electrically neutral biomolecules and plasma proteins. We studied the affinity between human and bovine serum albumins (HSA and BSA, respectively) and three neutral endogenous steroid hormones (testosterone, epitestosterone and androstenedione) and two synthetic analogues (methyltestosterone and fluoxymesterone) by applying the partial-filling technique in ACE (PF-ACE). From the endocrinological point of view, the distribution of endogenous steroids among plasma components is of great interest. Strong interactions with albumins suppress the biological activity of steroids. Notable differences in the association constants were observed. In the case of the endogenous steroids, the interactions between testosterone and the albumins were strongest, and those between androstenedione and the albumins were substantially weaker. The association constants, K(b), for testosterone, epitestosterone and androstenedione and HSA at 37 degrees C were 32 100 +/- 3600, 21 600 +/- 1500 and 13 300 +/- 1300 M(-1), respectively, while the corresponding values for the steroids and BSA were 18 800 +/- 1500, 14 000 +/- 400 and 7800 +/- 900 M(-1). Methyltestosterone was bound even more strongly than testosterone, while fluoxymesterone was only weakly bound by the albumins. Finally, the steroids were separated by PF-ACE with HSA and BSA used as resolving components.

  13. Scalp hair and saliva as biomarkers in determination of mercury levels in Iranian women: Amalgam as a determinant of exposure

    Energy Technology Data Exchange (ETDEWEB)

    Fakour, H., E-mail: fakour.h@gmail.com [Department of Environment, Faculty of Natural Resources and Marine Sciences, Tarbiat Modares University, Noor, Mazandaran (Iran, Islamic Republic of); Esmaili-Sari, A. [Department of Environment, Faculty of Natural Resources and Marine Sciences, Tarbiat Modares University, Noor, Mazandaran (Iran, Islamic Republic of); Zayeri, F. [Department of Biostatistics, Faculty of Paramedical Sciences and Proteomics Research Center, Shahid Beheshti University of Medical Sciences, Tehran (Iran, Islamic Republic of)

    2010-05-15

    The aim of this study was to determine the relationship between mercury concentrations in saliva and hair in women with amalgam fillings and its relation with age and number of amalgam fillings. Eighty-two hair and saliva samples were collected randomly from Iranian women who have the same fish consumption pattern and free from occupational exposures. The mean {+-} SD age of these women was 29.37 {+-} 8.12 (ranged from 20 to 56). The determination of Hg level in hair samples was carried out by the LECO, AMA 254, Advanced Mercury Analyzer according to ASTM, standard No. D-6722. Mercury concentration in saliva samples was analyzed by PERKIN-ELMER 3030 Cold Vapor Atomic Absorption Spectrophotometer. The mean {+-} SD mercury level in the women was 1.28 {+-} 1.38 {mu}g/g in hair and 4.14 {+-} 4.08 {mu}g/l in saliva; and there were positive correlation among them. A significant correlation was also observed between Hg level of saliva (Spearman's {rho} = 0.93, P < 0.001) and hair (Spearman's {rho} = 0.92, P < 0.001) with number of amalgam fillings. According to the results, we can conclude that amalgam fillings may be an effective source for high Hg concentration in hair and releasing the mercury to the saliva samples.

  14. Scalp hair and saliva as biomarkers in determination of mercury levels in Iranian women: Amalgam as a determinant of exposure

    International Nuclear Information System (INIS)

    Fakour, H.; Esmaili-Sari, A.; Zayeri, F.

    2010-01-01

    The aim of this study was to determine the relationship between mercury concentrations in saliva and hair in women with amalgam fillings and its relation with age and number of amalgam fillings. Eighty-two hair and saliva samples were collected randomly from Iranian women who have the same fish consumption pattern and free from occupational exposures. The mean ± SD age of these women was 29.37 ± 8.12 (ranged from 20 to 56). The determination of Hg level in hair samples was carried out by the LECO, AMA 254, Advanced Mercury Analyzer according to ASTM, standard No. D-6722. Mercury concentration in saliva samples was analyzed by PERKIN-ELMER 3030 Cold Vapor Atomic Absorption Spectrophotometer. The mean ± SD mercury level in the women was 1.28 ± 1.38 μg/g in hair and 4.14 ± 4.08 μg/l in saliva; and there were positive correlation among them. A significant correlation was also observed between Hg level of saliva (Spearman's ρ = 0.93, P < 0.001) and hair (Spearman's ρ = 0.92, P < 0.001) with number of amalgam fillings. According to the results, we can conclude that amalgam fillings may be an effective source for high Hg concentration in hair and releasing the mercury to the saliva samples.

  15. The effect of rebonding and liner type on microleakage of Class V amalgam restorations

    Directory of Open Access Journals (Sweden)

    Moosavi H.

    2008-10-01

    Full Text Available Background and Aim: Application of varnish and dentin bonding agents can effectively reduce microleakage under amalgam restorations. Also rebonding may show some effects on microleakage and its complications. The aim of this study was to evaluate the effect of liner/ adhesives on microleakage of Class V amalgam restoration with or without rebonding. Materials and Methods: In this in vitro study Class V cavities were prepared on sixty sound human maxillary premolars with the gingival floor 1mm below the CEJ. Cases were divided into six groups of ten teeth each. Specimens in group 1 and 2 were lined with Copalite and Scotchbond Multi-Purpose (SBMP respectively. In the third group (control no liner was applied. The teeth were then restored with spherical amalgam. Specimens in group 4 to 6 received the same treatments but after filling, the interfaces of restorations and teeth were etched with 37% phosphoric acid gel, rinsed and dried. Adhesive resin of SBMP was applied over amalgam and tooth margins and polymerized (rebonding. Specimens were thermocycled, exposed to dye and sectioned. Microleakage was graded (0-3 using a stereomicroscope at X40 magnification. Data were analyzed with Kruskal-Wallis, Mann-Whitney and Wilcoxon pair wise statistical tests. P<0.05 was considered as the limit of significance. Results: The groups lined with SBMP showed the lowest and the groups without liner the highest microleakage (p= 0.001. Significant difference was observed in microleakage mean rank of enamel and dentin margins (p=0.048. Rebonding with resin did not improve the seal (p> 0.05. Conclusion: Based on the results of this study, total etch adhesive system had significant effect on microleakage of Class V amalgam restorations especially in cervical margin. Rebonding did not show a significant effect on microleakage.

  16. [The "dental amalgam syndrome" - an environmental somatization Syndrome? A comparison between chronic carbon monoxide intoxication and illness related to dental amalgam].

    Science.gov (United States)

    Leonhardt, T

    2001-01-01

    In 1940, during World War II, restrictions in import of petroleum products to Sweden necessitated the use of producer gas in motor traffic. In the following years, the incidence of acute carbon monoxide intoxications raised steeply. However, many patients with minor but longstanding exposition to producer gas exhibited a neurastenic syndrome (fatigue, headaches and vertigo) thought to be specific. In Stockholm, an epidemic of this syndrome can afterwards be traced to the personal conviction of an internist who also had an important influence on various authorities, leading to a forceful campaign to the public about the dangers of using producer gas. After some years, the frequency and even the existence of a chronic carbon monoxide intoxication was called in question and at the end of the war that diagnosis lost its actuality. In Sweden, oral galvanism attributed to dental amalgam was discussed in mass media in the 1970s, not least by evidence given by some well-known personalities. In the 1980s, the frequency of illness attributed to dental amalgam increased to an important epidemic. The question of the dangers of mercury released from amalgam fillings is still an important issue of debate among dentists and physicians, although the majority remains sceptical. Also medical authorities have found little evidence of the importance of dental amalgam toxicity. A patients organisation, Tandvårdsskadeförbundet, seems to have played a significant part in the acceptance of the syndrome among laymen. Thus, various psychosocial factors seem to have played a role in both syndromes which could thus be conceived as environmental somatization syndromes.

  17. Analytical Applications of Solid and Paste Amalgam Electrodes

    Czech Academy of Sciences Publication Activity Database

    Josypčuk, Bohdan; Barek, J.

    2009-01-01

    Roč. 39, č. 3 (2009), s. 189-203 ISSN 1040-8347 R&D Projects: GA ČR GA203/07/1195; GA AV ČR IAA400400806; GA MŠk(CZ) LC06035 Institutional research plan: CEZ:AV0Z40400503 Keywords : solid amalgam electrodes * voltammetry * paste amalgam electrodes * reference amalgam electrodes Subject RIV: CG - Electrochemistry Impact factor: 2.621, year: 2009

  18. Study of high levels indoor air mercury contamination from mercury amalgam use in dentistry

    International Nuclear Information System (INIS)

    Khwaja, M.A.; Abbasi, M.S.; Mehmood, F.; Jahangir, S.

    2014-01-01

    In 2005, United Nations Environment Programme (UNEP) estimated that 362 tonnes of dental mercury are consumed annually worldwide. Dental mercury amalgams also called silver fillings and amalgam fillings are widely done. These fillings gave off mercury vapours. Estimated average absorbed concentrations of mercury vapours from dental fillings vary from 3,000 to 17,000 ng Hg. Mercury (Hg) also known as quick silver is an essential constituent of dental amalgam. It is a toxic substance of global concern. A persistent pollutant, mercury is not limited to its source but it travels, on time thousands of kilometers away from the source. Scientific evidence, including, UNEP Global Mercury report, establishes mercury as an extremely toxic substance, which is a major threat to wildlife, ecosystem and human health, at a global scale. Children are more at risk from mercury poisoning which affects their neurological development and brain. Mercury poisoning diminishes memory, attention, thinking and sight. In the past, a number of studies at dental sites in many countries have been carried out and reported which have been reviewed and briefly described. This paper describes and discusses the recent investigations, regarding mercury vapours level in air, carried out at 18 dental sites in Pakistan and other countries. It is evident from the data of 42 dental sites in 17 countries, including, selected dental sites in five main cities of Pakistan, described and discussed in this paper that at most dental sites in many countries including Pakistan, the indoor mercury vapours levels exceed far above the permissible limit, recommended for safe physical and mental health. At these sites, public, in general, and the medical, paramedical staff and vulnerable population, in particular, are at most serious risk to health resulting from exposure to toxic and hazardous mercury. (author)

  19. Technical quality of root canal fillings performed in a dental school and the associated retention of root-filled teeth: a clinical follow-up study over a 5-year period.

    LENUS (Irish Health Repository)

    Burke, F M

    2009-07-01

    The aim of this study was to examine the technical quality of root canal fillings performed in a dental school and to investigate the associated effect on the survival\\/retention of root-filled teeth. A review of case notes of patients who had root canal treatment performed in the department of Restorative Dentistry, University Dental School and Hospital, Cork, Ireland was carried out. The technical quality of the root canal filling was described according to its relationship with the radiographic apex on a post-treatment radiograph. Tooth status at review was defined as \\'tooth present\\' or \\'tooth absent\\' based on the presence or absence of the root-filled tooth recorded in the treatment records at a review appointment following placement of the root canal filling. One hundred and forty-eight teeth (129 patients) were considered. Of these, 69.6% (n = 103) were of acceptable technical quality, 23.6% (n = 35) were under-extended, and 6.8% (n = 10) were overextended. An increased number of intra-treatment radiographs to confirm the relationship of the canal preparation to the radiographic apex and operator experience were significant predictors of adequate root canal fillings (P < 0.05). Eighty-three per cent (n = 123) of teeth were present at a review appointment held an average of 40 months following completion of treatment (12-60 months). The technical quality of the root canal filling was the only significant factor in predicting tooth survival (P < 0.05), while the presence of pre-treatment periapical pathology had no significant effect on survival of the root-filled tooth. Determination and maintenance of the working length of the canal system is an important feature in producing good quality root canal fillings, which in turn, is associated with increased likelihood of survival\\/retention of root-filled teeth.

  20. Longitudinal Variation in Paleo-channel Complex Geometry and Associated Fill: Offshore South Carolina

    Science.gov (United States)

    Long, A. M.; Hill, J. C.

    2017-12-01

    In northeastern South Carolina, several shallow (migration of the ancestral Pee Dee River system along the southern limb of the Cape Fear Arch since the Pliocene. These paleo-channel complexes can be traced 80 km across the continental shelf via Boomer and Chirp subbottom data. The Murrells Inlet paleo-channel complex is the most well imaged offshore; and this data coverage provides an opportunity for a detailed seismic stratigraphic interpretation and analysis of downstream variability. Initial observations from this case study indicate that inner shelf incisions, where bedrock is folded and faulted, tend to be shallow with numerous channels, while the incisions across the middle shelf appear to be deeper and contains larger, more sinuous channels that are cut into broadly tilted strata with a gentle south-southeastward dip. This suggests the geometry and spatial distribution of the incisions were a function of the inherited fabric of the underlying basement, which created local deflection and areas of aggradation and degradation. The inner shelf paleo-channel complex fill is dominated by fluvial cut and fill seismic facies, while the middle shelf contains a wide variety of seismic facies (i.e. transparent, layered, chaotic, etc). This overall longitudinal fill pattern is most likely due to each location's general proximity to base level. The variation in the cut and fill seismic facies may be driven by substantial changes in discharge, driven locally by the joining of another major river or by climatic changes in the drainage basin. There also appears to be preferential reoccupation of previously filled paleo-channels, as the basement in this region is Tertiary and Cretaceous carbonates and siliciclastic rocks that are more resistant to erosion. The most recent occupation in any given paleo-channel tends to be on the southern margin, which may imply tectonic forcing from the uplift of the Cape Fear Arch. Preliminary results from this case study suggest that first

  1. Amalgam stained dentin: a proper substrate for bonding resin composite?

    NARCIS (Netherlands)

    Scholtanus, J.D.

    2016-01-01

    Nowadays the use of dental amalgam is mostly abandoned and substituted by tooth colored resin composites that can be bonded to teeth tissues by adhesive techniques. The aim of this thesis was to find out whether dark stained dentin, as often observed after removal of amalgam restorations and

  2. Neurotoxicity of dental amalgam is mediated by zinc.

    Science.gov (United States)

    Lobner, D; Asrari, M

    2003-03-01

    The use of dental amalgam is controversial largely because it contains mercury. We tested whether amalgam caused toxicity in neuronal cultures and whether that toxicity was caused by mercury. In this study, we used cortical cell cultures to show for the first time that amalgam causes nerve cell toxicity in culture. However, the toxicity was not blocked by the mercury chelator, 2,3-dimercaptopropane-1-sulphonate (DMPS), but was blocked by the metal chelator, calcium disodium ethylenediaminetetraacetate (CaEDTA). DMPS was an effective mercury chelator in this system, since it blocked mercury toxicity. Of the components that comprise amalgam (mercury, zinc, tin, copper, and silver), only zinc neurotoxicity was blocked by CaEDTA. These results indicate that amalgam is toxic to nerve cells in culture by releasing zinc. While zinc is known to be neurotoxic, ingestion of zinc is not a major concern because zinc levels in the body are tightly regulated.

  3. Interdependence of right ventricular systolic function and left ventricular filling and its association with outcome for patients with pulmonary hypertension.

    Science.gov (United States)

    Motoji, Yoshiki; Tanaka, Hidekazu; Fukuda, Yuko; Sano, Hiroyuki; Ryo, Keiko; Imanishi, Junichi; Miyoshi, Tatsuya; Sawa, Takuma; Mochizuki, Yasuhide; Matsumoto, Kensuke; Emoto, Noriaki; Hirata, Ken-ichi

    2015-04-01

    Although impaired right ventricular (RV) performance has been associated with adverse outcomes for pulmonary hypertension (PH) patients, the relationship between bi-ventricular interdependence and outcomes is not yet fully understood. We studied 96 PH patients. RV systolic function was assessed by means of RV free-wall longitudinal speckle-tracking strain (RV-free), and left ventricular (LV) filling as early diastolic transmitral flow velocity (TMF-E). RV-free ≤19 % and TMF-E functional class IV and brain natriuretic peptide >150 pg/dl (χ(2) = 1.2) was improved by the addition of RV-free (χ(2) = 5.5, p = 0.04) as well as of TMF-E (χ(2) = 11.5, p = 0.01). In conclusions, RV systolic function was shown to correlate significantly with LV filling in PH patients. In addition, not only assessment of RV systolic function, but also of a combined bi-ventricular parameter comprising RV systolic function and LV filling may well have clinical implications for more successful management of PH patients.

  4. The Thickness of Amalgamations and Cartesian Product of Graphs

    Directory of Open Access Journals (Sweden)

    Yang Yan

    2017-08-01

    Full Text Available The thickness of a graph is the minimum number of planar spanning subgraphs into which the graph can be decomposed. It is a measurement of the closeness to the planarity of a graph, and it also has important applications to VLSI design, but it has been known for only few graphs. We obtain the thickness of vertex-amalgamation and bar-amalgamation of graphs, the lower and upper bounds for the thickness of edge-amalgamation and 2-vertex-amalgamation of graphs, respectively. We also study the thickness of Cartesian product of graphs, and by using operations on graphs, we derive the thickness of the Cartesian product Kn □ Pm for most values of m and n.

  5. Crystallic silver amalgam – a novel electrode material

    Czech Academy of Sciences Publication Activity Database

    Daňhel, A.; Mansfeldová, Věra; Janda, Pavel; Vyskočil, V.; Barek, J.

    2011-01-01

    Roč. 136, č. 118 (2011), s. 36563662 ISSN 0003-2654 Institutional research plan: CEZ:AV0Z40400503 Keywords : crystallic silver amalgam * electrode materials * electrochemistry Subject RIV: CG - Electrochemistry Impact factor: 4.230, year: 2011

  6. Amalgam shear bond strength to dentin using different bonding agents.

    Science.gov (United States)

    Vargas, M A; Denehy, G E; Ratananakin, T

    1994-01-01

    This study evaluated the shear bond strength of amalgam to dentin using five different bonding agents: Amalgambond Plus, Optibond, Imperva Dual, All-Bond 2, and Clearfil Liner Bond. Flat dentin surfaces obtained by grinding the occlusal portion of 50 human third molars were used for this study. To contain the amalgam on the tooth surface, cylindrical plastic molds were placed on the dentin and secured with sticky wax. The bonding agents were then applied according to the manufacturers' instructions or light activated and Tytin amalgam was condensed into the plastic molds. The samples were thermocycled and shear bond strengths were determined using an Instron Universal Testing Machine. Analysis by one-way ANOVA indicated significant difference between the five groups (P < 0.05). The bond strength of amalgam to dentin was significantly higher with Amalgambond Plus using the High-Performance Additive than with the other four bonding agents.

  7. Effects of amalgam corrosion products on human cells

    Energy Technology Data Exchange (ETDEWEB)

    Goldschmidt, P R; Cogen, R B; Taubman, S B [Departments of Periodontics and Pathology, University of Connecticut Health Center, Farmington, Connecticut, U.S.A.

    1976-01-01

    Using three independent criteria, we have found that 10/sup -4/,10/sup -6/M concentrations of ions presumably liberated from the corrosion of dental amalgam produce injurious effects on either human gingival fibroblasts or HeLa cells when the cells are grown in culture. Release of /sup 51/Cr and uptake of trypan blue dye were seen with 10/sup -5/M Hg/sup + +/ and Ag/sup +/. Inhibition of amino acid incorporation into protein-like material was seen with eluates of amalgam and with ionic solutions of most metals comprising dental amalgam. Stannous ion showed little if any cytotoxic potential. These results suggest that corrosion products of amalgam are capable of causing cellular injury or destruction.

  8. Improving the strength of amalgams by including steel fibers

    Energy Technology Data Exchange (ETDEWEB)

    Cochran, Calvin T. [Hendrix College, Conway, AR 72032 (United States); Van Hoose, James R. [Siemens, Orlando, FL 32826 (United States); McGill, Preston B. [Marshall Space Flight Center, EM20, Huntsville, AL 35812 (United States); Grugel, Richard N., E-mail: richard.n.grugel@nasa.gov [Marshall Space Flight Center, EM30, Huntsville, AL 35812 (United States)

    2012-05-30

    Highlights: Black-Right-Pointing-Pointer A room temperature liquid Ga-In alloy was successfully substituted for mercury. Black-Right-Pointing-Pointer Physically sound amalgams with included steel fibers can be made. Black-Right-Pointing-Pointer A small volume fraction inclusion of fibers increased strength by {approx}20%. - Abstract: Mercury amalgams, due to their material properties, are widely and successfully used in dental practice. They are, however, also well recognized as having poor tensile strength. With the possibility of expanding amalgam applications it is demonstrated that tensile strength can be increased some 20% by including a small amount of steel fibers. Furthermore, it is shown that mercury can be replaced with a room temperature liquid gallium-indium alloy. Processing, microstructures, and mechanical test results of these novel amalgams are presented and discussed in view of means to further improve their properties.

  9. Working electrodes from amalgam paste for electrochemical measurements

    Czech Academy of Sciences Publication Activity Database

    Josypčuk, Bohdan; Šestáková, Ivana

    2008-01-01

    Roč. 20, č. 4 (2008), s. 426-433 ISSN 1040-0397 R&D Projects: GA ČR GA203/07/1195; GA ČR GA521/06/0496 Institutional research plan: CEZ:AV0Z40400503 Keywords : voltammetry * paste amalgam * silver amalgam * paste electrode Subject RIV: CG - Electrochemistry Impact factor: 2.901, year: 2008

  10. [Cermet cements for milk tooth fillings. Preliminary results].

    Science.gov (United States)

    Hickel, R; Petschelt, A; Voss, A

    1989-06-01

    106 Ketac-Silver fillings in deciduous molars were reevaluated after 1 to 3.3 years, i.e. 25 month on the average. About 90% of 50 occlusal fillings and about 84% of 56 multisurface restorations were unchanged. Without claiming statistical evidence for their conclusiveness, we consider these results as an indication that cermet cements are a useful alternative to amalgam fillings in deciduous teeth, particularly since the life of these fillings is limited to the time until the milk tooth is physiologically lost.

  11. Amalgam bonding: visualization and clinical implications of adhesive displacement during amalgam condensation.

    Science.gov (United States)

    Tyler, D W; Thurmeier, J

    2001-01-01

    Resin adhesive was visualized in this in vitro study of amalgam bonding using methylene blue dye incorporated into the resin or by scanning electron microscopy. Class II amalgam cavities were prepared in extracted teeth previously stored in buffered formalin. The preparations were then restored following manufacturers' instructions, but included methylene blue dissolved in ethanol into the adhesive resin mixture. This procedure had little effect on the setting time of the resin. Following condensation and carving, excess resin was incorporated into the body of the restorations as well as onto all adjacent coronal surfaces with significant occlusal and proximal accumulations. Resin also accumulated in significant amounts on the gingival floor of the proximal box and at line angles and retentive grooves within the preparation. In conclusion, radiological studies demonstrated that artifacts produced by resin accumulation at the gingival floor of the box could be mistaken for an open margin or recurrent caries. Other potential clinical consequences of resin residue on tooth surfaces are discussed, including the problem of interproximal ledges and occlusal discrepancies. The incorporation of a radiopaque material in the resin systems should be a universal requirement.

  12. Improved orthodontic bonding to silver amalgam. Part 2. Lathe-cut, admixed, and spherical amalgams with different intermediate resins.

    Science.gov (United States)

    Büyükyilmaz, T; Zachrisson, B U

    1998-08-01

    Flat rectangular tabs (n = 270) prepared from spherical (Tytin), admixed (Dispersalloy) or lathe-cut amalgam (ANA 2000) were subjected to aluminum oxide sandblasting with either 50-mu or 90-mu abrasive powder. Mandibular incisor edgewise brackets were bonded to these tabs. An intermediate resin was used, either All-Bond 2 Primers A + B or a 4-META product--Amalgambond Plus (AP) or Reliance Metal Primer (RMP)--followed by Concise. All specimens were stored in water at 37 degrees C for 24 hours and thermocycled 1000 times from 5 degrees C to 55 degrees C and back before tensile bond strength testing. The bond strength of Concise to etched enamel of extracted, caries-free premolars was used as a control. Bond failure sites were classified using a modified adhesive remnant index (ARI) system. Results were expressed as mean bond strength with SD, and as a function relating the probability of bond failure to stress by means of Weibull analysis. Mean tensile bond strength in the experimental groups ranged from 2.9 to 11.0 MPa--significantly weaker than the control sample (16.0 MPa). Bond failure invariably occurred at the amalgam/adhesive interface. The strongest bonds were created to the spherical and lathe-cut amalgams (range 6.8 to 11.0 MPa). Bonds to the spherical amalgam were probably more reliable. The intermediate application of the 4-META resins AP and RMP generally created significantly stronger bonds to all three basic types of amalgam products than the bonds obtained with the All-Bond 2 primers. The effect of abrasive-particle size on bond strength to different amalgam surfaces was not usually significant (p > 0.05). The implications of these findings are discussed in relationship to clinical experience bonding orthodontic attachments to large amalgam restorations in posterior teeth.

  13. Novel Amalgams for In-Space Fabrication of Replacement Parts

    Science.gov (United States)

    Cochran, Calvin T.; Van Hoose, James R.; Grugel, R. N.

    2012-01-01

    Being able to fabricate replacement parts during extended space flight missions precludes the weight, storage volume, and speculation necessary to accommodate spares. Amalgams, widely used in dentistry, are potential candidates for fabricating parts in microgravity environments as they are moldable, do not require energy for melting, and do not pose fluid handling problems. Unfortunately, amalgams have poor tensile strength and the room temperature liquid component is mercury. To possibly resolve these issues a gallium-indium alloy was substituted for mercury and small steel fibers were mixed in with the commercial alloy powder. Subsequent microscopic examination of the novel amalgam revealed complete bonding of the components, and mechanical testing of comparable samples showed those containing steel fibers to have a significant improvement in strength. Experimental procedures, microstructures, and test results are presented and discussed in view of further improving properties.

  14. Kinetic study of lithium-cadmium ternary amalgam decomposition

    International Nuclear Information System (INIS)

    Cordova, M.H.; Andrade, C.E.

    1992-01-01

    The effect of metals, which form stable lithium phase in binary alloys, on the formation of intermetallic species in ternary amalgams and their effect on thermal decomposition in contact with water is analyzed. Cd is selected as ternary metal, based on general experimental selection criteria. Cd (Hg) binary amalgams are prepared by direct contact Cd-Hg, whereas Li is formed by electrolysis of Li OH aq using a liquid Cd (Hg) cathodic well. The decomposition kinetic of Li C(Hg) in contact with 0.6 M Li OH is studied in function of ageing and temperature, and these results are compared with the binary amalgam Li (Hg) decomposition. The decomposition rate is constant during one hour for binary and ternary systems. Ageing does not affect the binary systems but increases the decomposition activation energy of ternary systems. A reaction mechanism that considers an intermetallic specie participating in the activated complex is proposed and a kinetic law is suggested. (author)

  15. Class II glass ionomer cermet tunnel, resin sandwich and amalgam restorations over 2 years.

    Science.gov (United States)

    Wilkie, R; Lidums, A; Smales, R

    1993-08-01

    This study compared the clinical behavior of a glass ionomer (polyalkenoate) silver cermet, a posterior resin composite used with the "tunnel" technique, a posterior resin composite used with the "closed sandwich" technique, and a high-copper amalgam for restoring small, proximal surface carious lesions. Two dentists placed 86 restorations in the posterior permanent teeth of 26 adults treated at a dental hospital. Restorations were assessed at 6-month intervals over 2 years for gingivitis adjacent to them, the tightness of proximal contacts, occlusal wear, surface voids, roughness and cracking, surface and marginal staining, and marginal fracture. Small filling defects, surface voids and occlusal wear were obvious with the cermet material, with surface crazing and cracking present in 48% of the tunnel restorations. Two of the posterior resin composites, but none of the amalgam restorations, also failed. The cermet cannot be recommended as a long-term permanent restorative material in situations where it is likely to be subjected to heavy occlusal stresses and abrasive wear.

  16. Microleakage of bonded amalgam restorations using different adhesive agents with dye under vacuum: An in vitro study

    Directory of Open Access Journals (Sweden)

    Abhishek Parolia

    2011-01-01

    Clinical Significance: Bonded amalgam restorations prevent over-preparation and reduce the tooth flexure. GIC type I under amalgam provides chemical bonding in between amalgam and tooth structure and thus reduces the microleakage.

  17. Radial multipliers on amalgamated free products of II-factors

    DEFF Research Database (Denmark)

    Möller, Sören

    2014-01-01

    Let ℳi be a family of II1-factors, containing a common II1-subfactor 풩, such that [ℳi : 풩] ∈ ℕ0 for all i. Furthermore, let ϕ: ℕ0 → ℂ. We show that if a Hankel matrix related to ϕ is trace-class, then there exists a unique completely bounded map Mϕ on the amalgamated free product of the ℳi...... with amalgamation over 풩, which acts as a radial multiplier. Hereby, we extend a result of Haagerup and the author for radial multipliers on reduced free products of unital C*- and von Neumann algebras....

  18. Development and Validation of a Prototype Vacuum Sensing Unit for the DD2011 Chairside Amalgam Separators

    Science.gov (United States)

    2015-10-30

    amalgam separators , such as the DD2011, remove amalgam waste particulates by filtration and are attached to the vacuum system of dental chairs for...based upon the principle that solid particulate amalgam waste and dental debris accumulate and block the movement of water through the filtration...AMALGAM SEPARATORS JAY SHARTZER, B.S., SOPHIA JOHNSON, PH.D., AND AMBER NAGY, PH.D. CRANIOFACIAL HEALTH AND RESTORATIVE MEDICINE BIOMATERIALS AND

  19. Determination of 5-nitroindazole using silver solid amalgam electrode

    Czech Academy of Sciences Publication Activity Database

    Nováková, Kateřina; Hrdlička, V.; Navrátil, Tomáš; Vyskočil, V.; Barek, J.

    2015-01-01

    Roč. 146, č. 5 (2015), s. 761-769 ISSN 0026-9247 R&D Projects: GA ČR(CZ) GAP208/12/1645 Institutional support: RVO:61388955 Keywords : 5-nitroindazole * hanging mercury drop electrode * silver sold amalgam electrode Subject RIV: CG - Electrochemistry Impact factor: 1.131, year: 2015

  20. Detecting DNA damage with a silver solid amalgam electrode

    Czech Academy of Sciences Publication Activity Database

    Kuchaříková, Kateřina; Novotný, Ladislav; Josypčuk, Bohdan; Fojta, Miroslav

    2004-01-01

    Roč. 16, č. 5 (2004), s. 410-414 ISSN 1040-0397 R&D Projects: GA AV ČR IAA4004108; GA AV ČR IBS5004355 Institutional research plan: CEZ:AV0Z5004920 Keywords : DNA damage * silver solid amalgam electrode * HMDE Subject RIV: BO - Biophysics Impact factor: 2.038, year: 2004

  1. Drop amalgam voltammetric study of lead complexation by natural ...

    African Journals Online (AJOL)

    A study of inorganic complexation of lead using drop amalgam voltammetry is described. The study has been carried out in simulated salt lake water and at ionic strength of 7.35 M, the predetermined ionic strength of Lake Katwe. The complexation of lead with the simple ligands (Cl-, CO32-) created anodic waves and the ...

  2. Mercury Amalgam Diffusion in Human Teeth Probed Using Femtosecond LIBS.

    Science.gov (United States)

    Bello, Liciane Toledo; da Ana, Patricia Aparecida; Santos, Dário; Krug, Francisco José; Zezell, Denise Maria; Vieira, Nilson Dias; Samad, Ricardo Elgul

    2017-04-01

    In this work the diffusion of mercury and other elements from amalgam tooth restorations through the surrounding dental tissue (dentin) was evaluated using femtosecond laser-induced breakdown spectroscopy (fs-LIBS). To achieve this, seven deciduous and eight permanent extracted human molar teeth with occlusal amalgam restorations were half-sectioned and analyzed using pulses from a femtosecond laser. The measurements were performed from the amalgam restoration along the amalgam/dentin interface to the apical direction. It was possible to observe the presence of metallic elements (silver, mercury, copper and tin) emission lines, as well as dental constituent ones, providing fingerprints of each material and comparable data for checking the consistence of the results. It was also shown that the elements penetration depth values in each tooth are usually similar and consistent, for both deciduous and permanent teeth, indicating that all the metals diffuse into the dentin by the same mechanism. We propose that this diffusion mechanism is mainly through liquid dragging inside the dentin tubules. The mercury diffused further in permanent teeth than in deciduous teeth, probably due to the longer diffusion times due to the age of the restorations. It was possible to conclude that the proposed femtosecond-LIBS system can detect the presence of metals in the dental tissue, among the tooth constituent elements, and map the distribution of endogenous and exogenous chemical elements, with a spatial resolution that can be brought under 100 µm.

  3. Staining of dentin from amalgam corrosion is induced by demineralization

    NARCIS (Netherlands)

    Scholtanus, J.D.; van der Hoorn, W.; Özcan, M.; Huysmans, M.C.D.N.J.M.; Roeters, J.F.M.; Kleverlaan, C.J.; Feilzer, A.J.

    2013-01-01

    PURPOSE: To evaluate the effect of artificial demineralization upon color change of dentin in contact with dental amalgam. METHODS: Sound human molars (n = 34) were embedded in resin and coronal enamel was removed. Dentin was exposed to artificial caries gel (pH 5.5) at 37 degrees C for 12 weeks (n

  4. Staining of dentin from amalgam corrosion is induced by demineralization

    NARCIS (Netherlands)

    Scholtanus, Johannes D.; van der Hoorn, Wietske; Huysmans, Marie-Charlotte D. N. J. M.; Roeters, Joost F. M.; Kleverlaan, Cornelis J.; Feilzer, Albert J.; Ozcan, Mutlu

    Purpose: To evaluate the effect of artificial demineralization upon color change of dentin in contact with dental amalgam. Methods: Sound human molars (n= 34) were embedded in resin and coronal enamel was removed. Dentin was exposed to artificial caries gel (pH 5.5) at 37 degrees C for 12 weeks (n=

  5. BACTERIAL ADHESION TO DENTAL AMALGAM AND 3 RESIN COMPOSITES

    NARCIS (Netherlands)

    SULJAK, JP; REID, G; WOOD, SM; MCCONNELL, RJ; VANDERMEI, HC; BUSSCHER, HJ

    Objectives: The ability of three oral bacteria to adhere to hydrophobic amalgam (water contact angle 60 degrees) and hydrophobic resin composites (Prisma-AP.H 56 degrees, Herculite XRV 82 degrees and Z100 89 degrees) was compared using an in vitro assay. Methods and results: Following preincubation

  6. Are institutional combinations, mergers or amalgamation the answer ...

    African Journals Online (AJOL)

    Many higher and further education institutions in South Africa are struggling to survive in a context of financial stringency, declining student enrolments and increasing competition. For some of these institutions merging or amalgamation with other institutions in the near future is becoming a strong likelihood. The perceptions ...

  7. Voltammetric determination of leucovorin using silver solid amalgam electrode

    Czech Academy of Sciences Publication Activity Database

    Šelešovská, R.; Bandžuchová, L.; Navrátil, Tomáš; Chýlková, J.

    2012-01-01

    Roč. 60, JAN 2012 (2012), s. 375-383 ISSN 0013-4686 R&D Projects: GA AV ČR IAA400400806; GA ČR GAP206/11/1638 Institutional research plan: CEZ:AV0Z40400503 Keywords : leucovorin * voltammetry * amalgam electrode Subject RIV: CG - Electrochemistry Impact factor: 3.777, year: 2012

  8. The Fiscal Imperative in the Amalgamation of 1914 | Lawal ...

    African Journals Online (AJOL)

    Many historians that have written about Nigeria have shown a great deal of interest in the factors, which accounted for the amalgamation of 1914 by which Nigeria was established as a single political entity. The various works, which have been published, have treated exhaustively the administrative and political factors.1 ...

  9. Surface modification for bonding between amalgam and orthodontic brackets.

    Science.gov (United States)

    Wongsamut, Wittawat; Satrawaha, Sirichom; Wayakanon, Kornchanok

    2017-01-01

    Testing of methods to enhance the shear bond strength (SBS) between orthodontic metal brackets and amalgam by sandblasting and different primers. Three hundred samples of amalgam restorations (KerrAlloy ® ) were prepared in self-cured acrylic blocks, polished, and divided into two groups: nonsandblasted and sandblasted. Each group was divided into five subgroups with different primers used in surface treatment methods, with a control group of bonded brackets on human mandibular incisors. Following the surface treatments, mandibular incisor brackets (Unitek ® ) were bonded on the amalgam with adhesive resin (Transbond XT ® ). The SBS of the samples was tested. The adhesive remnant index (ARI) and failure modes were then determined under a stereo-microscope. Two-way analysis of variance, Chi-square, and Kruskal-Wallis tests were performed to calculate the correlations between and among the SBS and ARI values, the failure modes, and surface roughness results. There were statistically significant differences of SBS among the different adhesive primers and sandblasting methods ( P 0.05). Using adhesive primers with sandblasting together effectively enhances the SBS between orthodontic metal brackets and amalgam. The two primers with the ingredient methacryloxydecyl dihydrogen phosphate (MDP) monomer, Alloy Primer ® and Assure Plus ® , were the most effective. Including sandblasting in the treatment is essential to achieve the bonding strength required.

  10. Coordinating a Large, Amalgamated REU Program with Multiple Funding Sources

    Science.gov (United States)

    Fiorini, Eugene; Myers, Kellen; Naqvi, Yusra

    2017-01-01

    In this paper, we discuss the challenges of organizing a large REU program amalgamated from multiple funding sources, including diverse participants, mentors, and research projects. We detail the program's structure, activities, and recruitment, and we hope to demonstrate that the organization of this REU is not only beneficial to its…

  11. Determination of Iodates using Silver Solid Amalgam Electrodes

    Czech Academy of Sciences Publication Activity Database

    Josypčuk, Bohdan; Novotný, Ladislav

    2002-01-01

    Roč. 14, 15/16 (2002), s. 1138-1142 ISSN 1040-0397 R&D Projects: GA ČR GV204/97/K084 Institutional research plan: CEZ:AV0Z4040901 Keywords : silver solid amalgam electrodes * voltammetry * table salt Subject RIV: CG - Electrochemistry Impact factor: 1.783, year: 2002

  12. 75 FR 33169 - Dental Devices: Classification of Dental Amalgam, Reclassification of Dental Mercury, Designation...

    Science.gov (United States)

    2010-06-11

    .... FDA-2008-N-0163] (formerly Docket No. 2001N-0067) RIN 0910-AG21 Dental Devices: Classification of Dental Amalgam, Reclassification of Dental Mercury, Designation of Special Controls for Dental Amalgam... the Federal Register of August 4, 2009 (74 FR 38686) which classified dental amalgam as a class II...

  13. Pengaruh Penambahan Paladium Terhadap Perilaku Thermal Amalgam Tembaga Tinggi Tipe Lathe Cut

    Directory of Open Access Journals (Sweden)

    Ellyza Herda

    2015-09-01

    Full Text Available Effects of additing 1 percent (w/o palladium (Pd on the thermal behavior of a lathe cut type high copper amalgam (13 w/o copper were studied. The identical alloys, with and without 1% Pd were fabricated. X-ray diffraction studies of the amalgams revealed the elimination of the γ2-phase by Pd addition DSC thermogram of non-Pd containing amalgam indicated the existence of two γ1-phaseone with the transition temperature (endothermic peak at 88◦C and the other at 109◦C. The thermogram data of the Pd containing amalgam showed an endothermic peak at 110.7◦C. The transition temperature of the n phase of the palladium containing amalgam is 4.9◦C lower than the transition temperature of the n phase of the non Pd containing amalgam. This result indicates that the n phase of the Pd containing amalgam includes more of Tin (Sn than the non-Pd containing amalgam. The thermogravimetri diagram showed that the phase decomposition occurred at about 390◦C for the non-Pd containing amalgam and at about 410◦C for the Pd containing amalgam. It is concluded that the addition of 1% Pd into a lathe cut type of high copper amalgam (13% could eliminate the formation of γ2 phase as well as an unstable γ1 phase, promoting strong mercury bonding to Silver.

  14. Changes in Enzyme Activities Involved in Starch Synthesis and Hormone Concentrations in Superior and Inferior Spikelets and Their Association with Grain Filling of Super Rice

    Directory of Open Access Journals (Sweden)

    Jing FU

    2013-03-01

    Full Text Available The changes in activities of key enzymes involved in sucrose-to-starch conversion and concentrations of hormones in superior and inferior spikelets of super rice were investigated and their association with grain filling was analyzed. Four super rice cultivars, Liangyoupeijiu, IIyou 084, Huaidao 9 and Wujing 15, and two high-yielding and elite check cultivars, Shanyou 63 and Yangfujing 8, were used. The activities of sucrose synthase (SuSase, adenosine diphosphoglucose pyrophosphorylase (AGPase, starch synthase (StSase and starch branching enzyme (SBE, and the concentrations of zeatin + zeatin riboside (Z + ZR, indole-3-acetic acid (IAA and abscisic acid (ABA in superior and inferior spikelets were determined during the grain filling period and their relationships with grain filling rate were analyzed. Maximum grain filling rate, the time reaching the maximum grain-filling rate, mean grain filling rate and brown rice weight for superior spikelets showed a slight difference between the super and check rice cultivars, but were significantly lower in the super rice than in the check rice for inferior spikelets. Changes of enzyme activities and hormone concentrations in grains exhibited single peak curves during the grain filling period. The peak values and the mean activities of SuSase, AGPase, StSase and SBE were lower in inferior spikelets than in superior ones, as well as the peak values and the mean concentrations of Z + ZR and IAA. However, the peak value and the mean concentration of ABA were significantly higher in inferior spikelets than in superior ones and greater in the super rice than in the check rice. The grain filling rate was positively and significantly correlated with the activities of SuSase, AGPase and StSase and the concentrations of Z + ZR and IAA. The results suggested that the low activities of SuSase, AGPase and StSase and the low concentrations of Z + ZR and IAA might be important physiological reasons for the slow grain

  15. Voltammetric Determination of Azidothymidine Using Silver Solid Amalgam Electrodes

    Czech Academy of Sciences Publication Activity Database

    Pecková, K.; Navrátil, Tomáš; Josypčuk, Bohdan; Moreira, J. C.; Leandro, K. Ch.; Barek, J.

    2009-01-01

    Roč. 21, č. 15 (2009), s. 1750-1757 ISSN 1040-0397 R&D Projects: GA ČR GA203/07/1195; GA AV ČR IAA400400806; GA MŠk(CZ) LC06035 Institutional research plan: CEZ:AV0Z40400503 Keywords : azidothymidine * Zidovudine * Silver solid amalgam electrode * Differential pulse voltammetry Subject RIV: CG - Electrochemistry Impact factor: 2.630, year: 2009

  16. Voltammetric Determination of Nitrophenols at a Silver Solid Amalgam Electrode

    Czech Academy of Sciences Publication Activity Database

    Fischer, J.; Vaňourková, L.; Daňhel, A.; Vyskočil, V.; Čížek, K.; Barek, J.; Pecková, K.; Josypčuk, Bohdan; Navrátil, Tomáš

    2007-01-01

    Roč. 2, - (2007), s. 226-134 ISSN 1452-3981 R&D Projects: GA MŠk(CZ) LC06063; GA ČR GA203/07/1195; GA MPO 1H-PK/42 Institutional research plan: CEZ:AV0Z40400503 Keywords : solid amalgam electrodes * voltammetry * nitrophenols * growth stimulators * solid phase extraction (SPE) Subject RIV: CF - Physical ; Theoretical Chemistry

  17. Amalgamation of performance indicators to support NRC senior management reviews

    International Nuclear Information System (INIS)

    Wreathall, J.; Schurman, D.; Modarres, M.; Mosleh, A.; Anderson, N.; Reason, J.

    1991-01-01

    The purpose of this project is to develop a methodology for amalgamating performance indicators to provide an overall perspective on plant safety, as one input to Nuclear Regulatory Commission's (NRC) senior management reviews of plant safety. These reviews are used to adjust the level of oversight by NRC. Work completed to date includes the development of frameworks for relating indicator measures to safety, a classification scheme for performance indicators, and a mapping process to portray indicators in the frameworks

  18. A model for amalgamation in group decision making

    Science.gov (United States)

    Cutello, Vincenzo; Montero, Javier

    1992-01-01

    In this paper we present a generalization of the model proposed by Montero, by allowing non-complete fuzzy binary relations for individuals. A degree of unsatisfaction can be defined in this case, suggesting that any democratic aggregation rule should take into account not only ethical conditions or some degree of rationality in the amalgamating procedure, but also a minimum support for the set of alternatives subject to the group analysis.

  19. Voltammetric Determination of Nitronaphthalenes at a Silver Solid Amalgam Electrode

    Czech Academy of Sciences Publication Activity Database

    Pecková, K.; Barek, J.; Navrátil, Tomáš; Josypčuk, Bohdan; Zima, J.

    2009-01-01

    Roč. 42, č. 15 (2009), s. 2339-2363 ISSN 0003-2719 R&D Projects: GA ČR GA203/07/1195; GA AV ČR IAA400400806; GA MŠk(CZ) LC06035 Institutional research plan: CEZ:AV0Z40400503 Keywords : cyclic voltammetry * differential pulse voltammetry * elimination voltammetry with linear scan * silver amalgam electrode Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.317, year: 2009

  20. Silver Solid Amalgam Electrodes as Sensors for Chemical Carcinogens

    Czech Academy of Sciences Publication Activity Database

    Barek, J.; Fischer, J.; Navrátil, Tomáš; Pecková, K.; Josypčuk, Bohdan

    2006-01-01

    Roč. 6, č. 4 (2006), s. 445-452 ISSN 1424-8220 R&D Projects: GA MPO 1H-PK/42; GA ČR GA203/03/0182 Institutional research plan: CEZ:AV0Z40400503 Keywords : solid amalgam electrodes * voltammetry * carcirogens * 3-nitrofluoranthene * Ostazine Orange Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.373, year: 2006

  1. MONITORING OF INTERNATIONAL DONOR ASSISTANCE IN THE CONTEXT OF THE DEVELOPMENT OF AMALGAMATED TERRITORIAL COMMUNITIES

    Directory of Open Access Journals (Sweden)

    Elina Boichenko

    2017-12-01

    Full Text Available The research is conducted within the framework of the joint project of the F. Ebert Foundation (Germany and the Institute of Economic and Legal Studies of the National Academy of Sciences of Ukraine (Ukraine “The Experience of the Association of Territorial Communities in Eastern Ukraine: Economic and Legal Aspects”. The subject of the study is the theoretical, methodological, and practical aspects of monitoring international donor assistance in the context of the development of amalgamated territorial communities (ATC based on the example of Bilokurakyne and Novopskov ATC. Methodology. The system approach (in substantiating the directions of monitoring and established procedures for monitoring each component of the life of amalgamated territorial communities, logical generalization (in determining the state of development of amalgamated territorial communities, method of absolute, relative, and mean values, analysis of the dynamics series and structural shifts (in determining the dominant trends in the formation and development of ATC, method of economic analysis and synthesis (in determining the content of the monitoring, method of comparison (when the violations in the process of ATC, graphical method (the construction algorithm combined operation and development of local communities imaging method (for presenting the results of the total amount of international aid to ATC are used in the work. The purpose of the research is to develop theoretical, methodological, and practical approaches to the monitoring of international donor assistance in the context of the development of amalgamated territorial communities. The article suggests using monitoring as the most effective tool for controlling economic and social phenomena and processes. The authorial scheme for constructing a procedure for the monitoring of functioning and development of amalgamated territorial communities is developed. The monitoring of international donor support of the

  2. Calculation of depleted uranium concentration in dental fillings samples using the nuclear track detector CR-39

    International Nuclear Information System (INIS)

    Mahdi, K. H.; Subhi, A. T.; Tawfiq, N. F.

    2012-12-01

    The purpose of this study is to determine the concentration of depleted uranium in dental fillings samples, which were obtained some hospital and dental office, sale of materials deployed in Iraq. 8 samples were examined from two different fillings and lead-filling (amalgam) and composite filling (plastic). concentrations of depleted uranium were determined in these samples using a nuclear track detector CR-39 through the recording of the tracks left by of fragments of fission resulting from the reaction 2 38U (n, f). The samples are bombarded by neutrons emitted from the neutron source (2 41A m-Be) with flux of ( 10 5 n. cm- 2. s -1 ). The period of etching to show the track of fission fragments is 5 hours using NaOH solution with normalization (6.25N), and temperature (60 o C ). Concentration of depleted uranium were calculated by comparison with standard samples. The result that obtained showed that the value of the weighted average for concentration of uranium in the samples fillings (5.54± 1.05) ppm lead to thr filling (amalgam) and (5.33±0.6) ppm of the filling composite (plastic). The hazard- index, the absorbed dose and the effective dose for these concentration were determined. The obtained results of the effective dose for each of the surface of the bone and skin (as the areas most affected by this compensation industrial) is (0.56 mSv / y) for the batting lead (amalgam) and (0.54 mSv / y) for the filling composite (plastic). From the results of study it was that the highest rate is the effective dose to a specimen amalgam filling (0.68 mSv / y) which is less than the allowable limit for exposure of the general people set the World Health Organization (WHO), a (1 mSv / y). (Author)

  3. Crystallic silver amalgam--a novel electrode material.

    Science.gov (United States)

    Danhel, Ales; Mansfeldova, Vera; Janda, Pavel; Vyskocil, Vlastimil; Barek, Jiri

    2011-09-21

    A crystallic silver amalgam was found to be a suitable working electrode material for voltammetric determination of electrochemically reducible organic nitro-compounds. Optimum conditions for crystal growth were found, the crystal surface was investigated by atomic force microscopy in tapping mode and single crystals were used for the preparation of quasi-cylindrical single crystal silver amalgam electrode (CAgAE). An electrochemical behavior of this alternative electrode material was investigated in aqueous media by direct current voltammetry, cyclic voltammetry (CV), differential pulse voltammetry (DPV) and adsorptive stripping voltammetry (AdSV) using 4-nitrophenol as a model compound. Applicable potential windows of the CAgAE were found comparable with those obtained at a hanging mercury drop electrode, providing high hydrogen overpotential, and polished silver solid amalgam electrode. Thanks to the smooth single crystal electrode surface, the effect of the passivation is not too pronounced, direct DPV determination of 100 μmol l(-1) of 4-nitrophenol at CAgAEs in 0.2 mol l(-1) acetate buffer pH 4.8 provides a RSD around 1.5% (n = 15). DPV calibration curves of 4-nitrophenol are linear in the whole concentration range 1-100 μmol l(-1) with a limit of quantification of 1.5 μmol l(-1). The attempt to increase sensitivity by application of AdSV was not successful. The mechanism of 4-nitrophenol reduction at CAgAE was investigated by CV.

  4. Radiopaque zones in the dentin beneath amalgam restorations

    International Nuclear Information System (INIS)

    You, Young Jun; Ahn, Hyung Kyu

    1978-01-01

    The purpose of the present investigation is determine how frequently radiopaque zones are seen on standard intraoral film and to research some other things about radiopaque bones. This study obtained the following results: 1. According to the standard intraoral films of the charts that were kept at the Dept. of Oral Diagnosis in Seoul National University Hospital, radiopaque zones were found in the rate of 4.1% among 1150 cases of amalgam-restored teeth that were treated at least two years ago. 2. Out of teeth that possessed radiopaque zones, 38.3% had radiolucent area between amalgam restoration and radiopaque zone. 3. Out of teeth that possessed radiopaque zones, 36.2% had cement base between amalgam restoration and radiopaque zone. 4. Out of teeth that possessed radiopaque zones, no tooth had periapical radiolucency. 5. Radiopaque zones were found more frequently in the mandibular teeth than the maxillary teeth. 6. According to the result of direct x-ray taking of 50 teeth that were treated at least 2 years ago, 6% had radiopaque zone.

  5. The Impact of Amalgamations on Services in Icelandic Municipalities

    Directory of Open Access Journals (Sweden)

    Grétar Thór Eythórsson

    2018-03-01

    Full Text Available This article deals with answering the question whether municipal amalgamations can meet the wishes at the root of the most common motives behind them: to gain cost-efficiency and more quality in the municipal services. The analysis is partly based on a survey among Icelandic local leaders in 2015 and partly on survey among citizens in 8 recently amalgamated municipalities collected with a snowball method through Facebook in the spring and summer 2013. The main results are that the impact of amalgamations on municipal services seems to depend on whether we look at the central or peripheral parts of the municipality. Both leaders and citizens seem to perceive developments of services differently depending on the position in the municipality. In the peripheries, they have significantly more negative view than in the service centres. This has to do with both their evaluation of specific services and their general evaluation of service development. However, in the general evaluation the difference is significantly larger.

  6. Increased Microleakage of Amalgam Restorations after Exposure to 2.4 Ghz Radiofrequency Electromagnetic Fields from Common Wi-Fi Routers

    Directory of Open Access Journals (Sweden)

    Mortazavi SMJ

    2017-09-01

    Full Text Available Statement of Problem: Previous studies have shown that exposure of dental amalgam fillings to MRI and mobile phones can increase microleakage of amalgam restorations. Objectives: The aim of this study was to evaluate the effects of exposure to radiofrequency radiation emitted from indoor Wi-Fi access devices on microleakage of amalgam restorations. Materials and Methods: Standard class V cavities were prepared on the buccal surfaces of 69 extracted human premolar teeth. The samples were divided into two exposure groups and one non-exposed control group of 23 teeth each. The specimens in the experimental groups were exposed to a radiofrequency (RF radiation emitted from a commercial 2.4 GHz Wi Fi router. The distance between the Wi-Fi router and samples was 30 cm and the router was exchanging data with a laptop computer that was placed 20 m away from the router. Teeth samples in the first exposure group (group A were exposed to RF for 3 days while the second exposure group (group B was exposed for 6 days. Then the teeth were sectioned and scored for microleakage under a stereomicroscope. Results: The score of microleakage was significantly higher in the exposure group A compared to that of the control group. However, the score of microleakage was not significantly different between the exposure group B and control group. Furthermore, the scores of microleakage was signifi-cantly higher in the exposure group A than that of the exposure group B. Conclusions: Exposure of patients with amalgam restorations to radiofre-quency waves emitted from commercial Wi-Fi routers can lead to in-creased microleakage of amalgam restorations.

  7. Clinical study of the marginal microfiltration in restorations with amalgam applying sealant cavitario

    OpenAIRE

    Lahoud Salem, Víctor; Mendoza Zapata, Janet; Vidal Goñi, Raúl

    2014-01-01

    The present study to evaluate the clinical evaluation, marginal leakage of 30 amalgams restorations with sealers cavity and 30 amalgams restorations not sealers cavity. After of 12 months observation in amalgams restorations with sealers cavity 100% success in marginal leakage and not presents of secondary caries, not to have presents clinical cases of sensitivity post-operative and pulp inflammation. El presente estudio consistió en evaluar clínicamente la microfiltración marginal en 30 r...

  8. Estimated quantity of mercury in amalgam waste water residue released by dentists into the sewerage system in Ontario, Canada.

    Science.gov (United States)

    Adegbembo, Albert O; Watson, Philip A

    2004-12-01

    To estimate the quantity of dental amalgam that Ontario dentists release into waste water. Information from a self-administered postal survey of Ontario dentists was combined with the results of other experiments on the weight of amalgam restorations and the quantity of amalgam waste that bypasses solids separators in dental offices. Algorithms were developed to compute the quantity of amalgam waste leaving dental offices when dentists used or did not use ISO 11143 amalgam particle separators. A total of 878 (44.0%) of 1,994 sampled dentists responded to the survey. It was estimated that Ontario dentists removed 1,880.32 kg of amalgam (940.16 kg of mercury) during 2002, of which 1,128.19 kg of amalgam (564.10 kg of mercury) would have been released into waste water in Ontario if no dentists had been using a separator. Approximately 22% of the dentists reported using amalgam particle separators. On the basis of current use of amalgam separators, it was estimated that 861.78 kg of amalgam (430.89 kg of mercury or 170.72 mg per dentist daily) was released in 2002. The use of amalgam separators by all dentists could reduce the quantity of amalgam (and mercury) entering waste water to an estimated 12.41 kg (6.21 kg of mercury, or 2.46 mg per dentist per day). Amalgam particles separators can dramatically reduce amalgam and mercury loading in waste water released from dental offices.

  9. Managing amalgam phase down: An evaluation of mercury vapor levels in a dental center in Lagos, Nigeria

    Directory of Open Access Journals (Sweden)

    Adolphous Odofin Loto

    2017-01-01

    Full Text Available Background: Occupational exposure to elemental mercury vapor in a dental setting is mainly through inhalation exposure during preparation, insertion, polishing, and removal of amalgam fillings including storage of amalgam waste before disposal. This study aims to determine the indoor air levels of elemental mercury vapor in the dental operatories and ancillary sites at the Lagos State University Teaching Hospital (LASUTH. Materials and Methods: Samples of the ambient air were taken at seven locations the Dental Center of LASUTH by a trained technician between 9:00 and 11:00 a.m. This was done at a predetermined height (41/2feet above the floor for mercury vapor concentration using Lumex 915 light data logger mercury vapor analyzer manufactured by Ohio Lumex Company Incorporation, USA®. Results: The highest level of 1434 ng/m3 of mercury vapor in the air was found in the restorative clinic while the lowest of 23 ng Hg/m3 was found in the ambient air at the entrance of the dental Center. The Oral Surgery clinic had mercury vapor level of 318 ng/m3 which was slightly higher than Environmental Protection Agency recommended value of 0.3 μg/m3. Conclusion: An unacceptably high level of mercury vapor was detected, especially in the restorative clinic. Every dental clinic should have its ambient air evaluated for mercury vapor level for the purpose of forming a baseline data for monitoring purposes during the period of phase down of amalgam use. Best practices should also be instituted to reduce the level of exposure of patients and dental care workers to mercury vapor.

  10. Assessment of manual restorative treatment (MRT) with amalgam in high-caries Filipino children: results after 2 years.

    Science.gov (United States)

    Monse-Schneider, B; Heinrich-Weltzien, R; Schug, D; Sheiham, A; Borutta, A

    2003-04-01

    The atraumatic restorative treatment (ART), using only hand instruments and glass-ionomer cement as adhesive material is recommended for restorative dental treatment in disadvantaged communities lacking electricity and sophisticated dental equipment. Research is required on more durable restorative materials appropriate for populations with high-caries experience. The aim of the study was to evaluate, under field conditions, the applicability and effectiveness of an encapsulated amalgam as restorative material in ART prepared cavities in permanent teeth of children with high-caries rates. As the definition of ART restricts the manual treatment to adhesive materials the approach used is called the manual restorative treatment (MRT). Two dentists and two trained healthcare workers, using hand instruments and an encapsulated amalgam that was mixed with a manually driven triturator, placed a total of 934 restorations in the permanent dentition in 466 children. Due to irregular school attendance of Filipino children only 611 restorations could be evaluated by one independent dentist. The average age at reassessment of restorations was 27 +/- 4.5 months. 93.3% of the restorations were acceptable. The failure rate of occlusal surface restorations was 5.6% compared with 13.6% of buccal surface fillings. The survival rate of large occlusal restorations was 95.1% compared with 93.7% for small restorations. The survival of MRT restorations was not influenced by the experience and professional level of the operator. Amalgam is a suitable MRT material, especially for extensive occlusal lesions in high-caries populations. Studies of longer duration are needed to confirm this finding.

  11. Exposure to mercury and silver during removal of amalgam restorations

    International Nuclear Information System (INIS)

    Brune, D.; Hensten-Pettersen, A.; Beltesbrekke, H.

    1980-01-01

    The content of particulate matter and mercury vapor in dentist breathing air during removal of amalgam restorations was assessed. Mercury and silver were quantitatively assayed by nuclerar chemical analysis, and the mercury vapor concentration was measured with a sniffer. When the water spray was not used, the short time threshold limit values for exposure to mercury and silver were exceeded about 10 times. With water spray the mercury content was reduced to a level considerably lower that the threshold limit value, whereas the silver concentration slightly exceeded the corresponding limit. (author)

  12. Exposure to mercury and silver during removal of amalgam restorations

    International Nuclear Information System (INIS)

    Brune, D.; Hensten-Pettersen, A.; Beltesbrekke, H.

    1980-01-01

    The content of particulate matter and mercury vapor in dentist breathing air during removal of amalgam restorations was assessed. Mercury and silver were quantitatively assayed by nuclear chemical analysis, and the mercury vapor concentration was measured with a sniffer. When the water spray was not used, the short time threshold limit values for exposure to mercury and silver were exceeded about 10 times. With water spray the mercury content was reduced to a level considerably lower than the threshold limit value, whereas the silver concentration slightly exceeded the corresponding limit. (author)

  13. Reasons for Retreatment of Amalgam and Composite Restorations among the Patients Referring to Tabriz Faculty of Dentistry

    Directory of Open Access Journals (Sweden)

    Siavash Savadi Oskoee

    2007-06-01

    Full Text Available

    Background and aims. Retreatment of existing restorations not only requires a lot of money and time but also there is a danger of weakening tooth structure and irritating the pulp. Since awareness of the reasons for the retreatment of teeth will save the teeth from possible future failure, the aim of this study was to assess the reasons for retreatment of amalgam and composite restorations in patients referring to Tabriz Faculty of Dentistry.

    Materials and methods. In this descriptive study, the subjects had previously received an amalgam or a composite restoration in the Operative Department by dental students and were judged to need retreatment in their second visit. A total of 300 defective teeth were selected by simple random sampling method. The data was collected through examination and questionnaires and analyzed using chi-square test.

    Results. There was a statistically significant association between the type of the restorative material and the reason for retreatment (p=0.001.

    Conclusion. Although the reasons for the retreatment of amalgam and composite restorations were different, recurrent caries was the main reason for the retreatment for both restorative materials.

  14. Localized Glacier Deformation Associated with Filling and Draining of a Glacier-Dammed Lake and Implications for Outburst Flood Hydraulics

    Science.gov (United States)

    Cunico, M. L.; Walder, J. S.; Fountain, A. G.; Trabant, D. C.

    2001-12-01

    During the summer of 2000, we measured displacements of 22 survey targets on the surface of Kennicott Glacier, Alaska, in the vicinity of Hidden Creek Lake, an ice-dammed lake in a tributary valley that fills and drains annually. Targets were distributed over a domain about equal in width to the lake, from near the glacier/lake margin to a distance of about 1 km from the margin. Targets were surveyed over a 24-day period as the lake filled and then drained. Lake stage was independently monitored. Vertical movement of targets generally fell off with distance d from the lake. As the lake filled, targets with d typically about 0.5 m/d--with a few targets rising slightly faster than the lake. The rate of vertical movement fell off rapidly with distance from the lake: for d = ca. 600 m--roughly twice the local ice thickness--targets moved upward only about 10% as fast as lake stage. Vertical movement of targets with d > ca. 1 km seemed to be uncorrelated with lake stage. The general pattern is consistent with the idea that a wedge of water extended beneath the glacier to a distance of perhaps 300 to 400 m from the visible margin of the lake and exerts buoyant stresses on the ice that were transmitted into the main body of the glacier and caused flexure. This scenario bears some resemblance to tidal deflections of ice shelves or tidewater glaciers. For a given value of lake stage, target elevations were invariably higher as the lake drained than as the lake filled. Moreover, survey targets at a distance of about 400 m or more from the lake continued to rise for some time even after the lake began to drain. The lag time between the beginning of lake drainage and the beginning of target downdrop increased with distance from the lake, with the lag being about 14 hours at a distance of 400 m from the lake. (The lake drained completely in approximately 75 hours.) The likeliest explanations for the departure from reversibility and the existence of the time lag are either (i) a

  15. A variety of amalgamated allusion in Saeb’s sonnet

    Directory of Open Access Journals (Sweden)

    Siavash Haghjoo

    2014-12-01

    Full Text Available Abstract Poetic figures of speech are among the factors which their prominence in a poet’s poetry makes up his/her specific style. One of the figures of speech and poetic techniques is allusive figures of speech or amalgamated allusions. As the name entails, these are types of figures in which allusion is located at the center and amalgamates with other figures. Such amalgamation brings about a novel complicated figure of speech.  One special type of allusive figures of speech is an allusion which is occasionally amalgamated with metaphor and ambiguity, and at times in addition to metaphor and ambiguity with simile. The origin of this figure, which is recently referred to as “metaphoric ambiguous allusion, is traced back to Hakim baz in Persian literature. Although, poetry of Hafez is replete with metaphoric ambiguous allusion, it is considerably ubiquitous in Indian style in a way that its ignorance especially in Saeb’s poetry implies the denial of one of its foremost stylistic qualities. The mixed nature of this figure and the presence of several robust figures besides each other which are the basis of poetic fantasy and a fantastic presentation is created by combination of these figures. These figures invite readers into a mode of reflection and thinking and opens corridors of fantasy towards him replete with unsurpassable satisfaction. Such amalgamated figure is formed when a poet grants an allusion to a phenomenon which in reality the phenomenon owns such quality but in a different conceptualization. Supposedly, the given figure was Saeb’s major artifact which helped him to fulfill his distinct poetic quality i.e. unsurpassed power of creating vivacious contents. The present article intended to conduct a supplementary reanalysis of “metaphoric ambiguous allusion and its different varieties and examined it in Saeb’s Poetry. Metaphoric ambiguous allusion refers to a metaphor which alludes to something. The characteristics of the

  16. The impact of altering filling pressures in diagnostic outpatient hysteroscopy on the procedure completion rates and associated pain: a randomised double-blind controlled trial.

    Science.gov (United States)

    Haggag, Hisham M; Hassan, AbdelGany M A

    2016-02-01

    Several studies have compared different distension media and analgesics to optimise the efficiency of outpatient hysteroscopy. However, studies comparing different uterine filling pressures are scarce. The objective of this study was to evaluate and compare different uterine filling pressures during diagnostic outpatient hysteroscopy in an attempt to find the optimal pressure allowing adequate visualisation while minimising pain and increasing patient satisfaction. This was a double-blind randomised controlled trial. A total of 240 women who had diagnostic outpatient hysteroscopy were randomly divided into three equal groups: the uterine filling pressure was 30 mm Hg in group 1, 50 mm Hg in group 2 and 80 mm Hg in group 3. The primary outcome was adequate visualisation, and secondary outcomes were the proportion of completed procedures, pain perceived during the procedure, immediately after the procedure and 30 min later. Adequate visualisation was lower in group 1 (88.7% vs 97.5% and 98.7%; P = 0.009), but was not different between groups 2 and 3 (P > 0.999). The proportion of completed procedures was not different among the groups. There was a progressive increase in pain scores from the lower to the higher pressure groups during the procedure, immediately after the procedure and 30 min after completing the procedure. Uterine filling pressure of 50 mm Hg was associated with better visualisation than 30 mm Hg and lower pain scores than that of 80 mmHg with no difference in the proportion of completed procedures. © 2015 The Royal Australian and New Zealand College of Obstetricians and Gynaecologists.

  17. Benchmarking Parameter-free AMaLGaM on Functions With and Without Noise

    NARCIS (Netherlands)

    P.A.N. Bosman (Peter); J. Grahl; D. Thierens (Dirk)

    2013-01-01

    htmlabstractWe describe a parameter-free estimation-of-distribution algorithm (EDA) called the adapted maximum-likelihood Gaussian model iterated density-estimation evolutionary algorithm (AMaLGaM-IDEA, or AMaLGaM for short) for numerical optimization. AMaLGaM is benchmarked within the 2009 black

  18. On Reduced Amalgamated Free Products of C*-algebras and the MF-Property

    DEFF Research Database (Denmark)

    Seebach, Jonas A.

    We establish an isomorphism of the group von Neumann algebra of an amalgamated free product of countable Abelian discrete groups. This result is then used to give some new examples of reduced group $ C^* $-algebras which are MF. Finally, we give a characterization of the amalgamated free products...

  19. The amalgam of faith and reason: Euclid’s Elements and the scientific thinker

    DEFF Research Database (Denmark)

    Andrade-Molina, Melissa; Valero, Paola; Ravn, Ole

    2017-01-01

    child intertwines with what was ought to be the ‘scientific thinker’ to Christianity. We focus on how Euclidean geometry, taken as a proper method of inquiry amalgamated with the Christian worldview to provide explanations about the natural world. In modern education, the core of this amalgamation...

  20. Reasons for failure and replacement of class I and class II amalgam ...

    African Journals Online (AJOL)

    Aim: The aim of this study is to evaluate the reasons for failure of amalgam restorations in a teaching hospital. Method: A structured questionnaire was used to obtain information from patients presenting with failed amalgam restorations in the conservative clinic of a teaching hospital. The questionnaire was administered by ...

  1. Poor quality evidence suggests that failure rates for atraumatic restorative treatment and conventional amalgam are similar.

    Science.gov (United States)

    Hurst, Dominic

    2012-06-01

    The Medline, Cochrane CENTRAL, Biomed Central, Database of Open Access Journals (DOAJ), OpenJ-Gate, Bibliografia Brasileira de Odontologia (BBO), LILACS, IndMed, Sabinet, Scielo, Scirus (Medicine), OpenSIGLE and Google Scholar databases were searched. Hand searching was performed for journals not indexed in the databases. References of included trials were checked. Prospective clinical trials with test and control groups with a follow up of at least one year were included. Data abstraction was conducted independently and clinical and methodologically homogeneous data were pooled using a fixed-effects model. Eighteen trials were included. From these 32 individual dichotomous datasets were extracted and analysed. The majority of the results show no differences between both types of intervention. A high risk of selection-, performance-, detection- and attrition bias was identified. Existing research gaps are mainly due to lack of trials and small sample size. The current evidence indicates that the failure rate of high-viscosity GIC/ART restorations is not higher than, but similar to that of conventional amalgam fillings after periods longer than one year. These results are in line with the conclusions drawn during the original systematic review. There is a high risk that these results are affected by bias, and thus confirmation by further trials with suitably high numbers of participants is needed.

  2. Clinical longevity of extensive direct composite restorations in amalgam replacement : Up to 3.5 years follow-up

    NARCIS (Netherlands)

    Scholtanus, Johannes D.; Ozcan, Mutlu

    Objectives: This prospective clinical trial evaluated the longevity of direct resin composite (DRC) restorations made on stained dentin that is exposed upon removal of existing amalgam restorations in extensive cavities with severely reduced macro-mechanical retention for amalgam replacement.

  3. An evaluation of a lathe-cut high-copper amalgam alloy.

    Science.gov (United States)

    Knibbs, P J; Plant, C G; Shovelton, D S; Jones, P A

    1987-09-01

    Modification of an amalgam alloy may give rise to improved physical properties. The physical properties of a newly formulated, single-composition lathe-cut amalgam alloy were studied and found to be superior to those of a conventional lathe-cut amalgam alloy. However, such modification in formulation may result in changes in the clinical handling properties of the material. The high-copper amalgam alloy was assessed by a panel of general practitioners who found that the general handling properties of the material were similar to those of conventional lathe-cut amalgam alloys. The longer term performance of the high-copper alloy was assessed by means of a blind, controlled clinical trial carried out by two operators. A 1-year assessment of the resulting restorations and tooth replicas could not distinguish between the high-copper alloy and a conventional alloy. The two alloys had both given good clinical results.

  4. Effect of ProRoot MTA, Portland cement, and amalgam on the expression of fibronectin, collagen I, and TGFβ by human periodontal ligament fibroblasts in vitro.

    Science.gov (United States)

    Fayazi, Sara; Ostad, Seyed Nasser; Razmi, Hasan

    2011-01-01

    Today many materials have been introduced for root-end filling materials. One of them is mineral trioxide aggregate (MTA) that is mentioned as a gold standard. The purpose of this in vitro study was to evaluate the reaction of human periodontal ligament fibroblasts to the root-end filling materials, such as ProRoot MTA, Portland cement, and amalgam. Eight impacted teeth were extracted in aseptic condition. The tissues around the roots were used to obtain fibroblast cells. After cell proliferation, they were cultured in the chamber slides and the extracts of the materials were added to the wells. Immunocytochemical method for measuring the expression of Fibronectin, collagen I and transforming growth factor beta (TGF®) was performed by Olysia Bioreport Imaging Software. The results were analyzed by SPSS 13.0 and Tukey post hoc test with PPortland cement group showed the most expression of collagen significantly and after 1 week, Portland cement and MTA groups had the most expression of collagen but there was no significant difference between these 2 groups. After 1 week, the Portland cement group demonstrated a higher amount of TGF® and fibronectin. The results suggest that Portland cement can be used as a less expensive root filling material with low toxicity. It has better effects than amalgam on the fibroblasts.

  5. Determination of trace arsenic on hanging copper amalgam drop electrode.

    Science.gov (United States)

    Piech, Robert; Baś, Bogusław; Niewiara, Ewa; Kubiak, Władysław W

    2007-04-30

    Hanging copper amalgam drop electrode has been applied for trace determination of arsenic by cathodic stripping analysis. Detection limit for As(III) as low as 0.33nM (0.02mug/L) at deposition time (240s) could be obtained. For seven successive determinations of As(III) at concentration of 5nM relative standard deviation was 2.5% (n=7). Interferences from selected metals and surfactant substances were examined. Absence of copper ions in sample solution causes easier optimization and makes method less vulnerable on contamination. The developed method was validated by analysis of certified reference materials (CRMs) and applied to arsenic determinations in natural water samples.

  6. Process Optimization for Valuable Metal Recovery from Dental Amalgam Residues

    Directory of Open Access Journals (Sweden)

    C.M. Parra–Mesa

    2009-07-01

    Full Text Available In this paper, the methodology used for optimizing leaching in a semi pilot plant is presented. This leaching process was applied to recover value metals from dental amalgam residues. 23 factorial design was used to characterize the process during the first stage and in the second one, a central compound rotational design was used for modeling copper percentage dissolved, a function of the nitric acid concentration, leaching time and temperature. This model explained the 81% of the response variability, which is considered satisfactory given the complexity of the process kinetics and, furthermore, it allowed the definition of the operation conditions for better copper recovery, which this was of 99.15%, at a temperature of 55°C, a concentration of 30% by weight and a time of 26 hours.

  7. Biomarkers of kidney integrity in children and adolescents with dental amalgam mercury exposure: Findings from the Casa Pia children's amalgam trial

    International Nuclear Information System (INIS)

    Woods, James S.; Martin, Michael D.; Leroux, Brian G.; DeRouen, Timothy A.; Bernardo, Mario F.; Luis, Henrique S.; Leitao, Jorge G.; Kushleika, John V.; Rue, Tessa C.; Korpak, Anna M.

    2008-01-01

    Mercury is toxic to the kidney, and dental amalgam is a source of mercury exposure. Few studies have evaluated the effects of dental amalgam on kidney function in a longitudinal context in children. Here, we evaluated urinary concentrations of glutathione S-transferases (GSTs) α and π as biomarkers of renal proximal and distal tubular integrity, respectively, and albumin as a biomarker of glomerular integrity in children and adolescents 8-18 years of age over a 7-year course of dental amalgam treatment. Five hundred seven children, 8-12 years of age at baseline, participated in a clinical trial to evaluate the neurobehavioral and renal effects of dental amalgam in children. Subjects were randomized to either dental amalgam or resin composite treatments. Urinary GSTs α and π, albumin, and creatinine concentrations were measured at baseline and annually in all subjects. Results were evaluated using linear regression analysis. GST-α concentrations were similar between treatment groups and in each sex and race (white vs. non-white) group in each follow-up year. GST-π levels tended upward over the course of follow-up by four- to six-fold. This increase was seen in all groups irrespective of the treatment, race, or gender. Females had GST-π levels approximately twice those of males at all ages. Albumin concentrations were constant throughout the follow-up period and did not differ by treatment, although females had 39% higher albumin levels than males. Additionally, we found no significant effects of amalgam treatment on the proportion of children with microalbuminuria (>30 mg/g creatinine). These findings are relevant within the context of children's health risk assessment as relates to the safety of mercury exposure from dental amalgam on kidney function. These data also provide normative values for sensitive indices of renal functional integrity that may serve in the evaluation of children and adolescents with renal disorders

  8. High resolution neutron tomography applied to tooth fillings on real teeth by use of neutron lens

    International Nuclear Information System (INIS)

    Masschaele, B.; Cauwels, P.; Mondelaers, W.; Baechler, S.; Jolie, J.; Materna, T.

    2000-01-01

    Today tomography is a well known technique for nondestructive analysis of samples. By taking several X-ray pictures from an object, it is possible to make a 3D reconstruction. The same thing can be done with neutrons. Since very recent it is possible to produce a high-flux neutron beam. By looking at the attenuation of the neutron beam in the sample from different angles, it is possible to make a neutron tomography. The properties of neutrons are so much different from X-rays that a new era in tomography has started. Where X-rays have a hard time penetrating samples containing heavy elements (Pb, Bi, U, Hg, Au), neutrons just seem to walk through. But when the neutrons encounter samples containing light compounds like water, oil, paper, B, Li,... they are easily absorbed. This makes the use of neutrons for imaging complementary to the well known X-ray imaging. The most used tooth filling material nowadays is amalgam. Amalgam is a mixture of different metals, like silver, tin, copper, mercury. Mercury is dangerous for the human body when it enters the blood stream. These fillings are very dense and X-rays have a very hard time penetrating it. Neutrons are the ideal probe for investigation of these high density regions. The result of the tomography reveals information on the long term stability of amalgam fillings and could help the still ongoing debate on the safety of the fillings. (author)

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

    Directory of Open Access Journals (Sweden)

    Aminatun Aminatun

    2006-09-01

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

  10. A novel method for the preparation of uranium metal, oxide and carbide via electrolytic amalgamation

    International Nuclear Information System (INIS)

    Wang, L.C.; Lee, H.C.; Lee, T.S.; Lai, W.C.; Chang, C.T.

    1978-01-01

    A solid uranium amalgam was prepared electrolytically using a two-compartment cell separated with an ion exchange membrane for the purpose of regulating pH value within a narrowly restricted region of 2 to 3. The mercury cathode was kept at -1.8V vs SCE during electrolysis. The thereby obtained amalgam containing as high as 1.9gm U/ml Hg is easily converted into uranium metal by heating in vacuo above 1300 0 C. Uranium dioxide and uranium monocarbide could be easily obtained at relatively low temperature by reacting the amalgam with water vapor and methane. (author)

  11. Investigation of the mechanism of mercury removal from a silver dental amalgam alloy

    Directory of Open Access Journals (Sweden)

    M. DJURDJEVIC

    2004-12-01

    Full Text Available An investigation of silver dental amalgam decomposition and the mercury removal mechanism was performed. The decomposition process was analysed during thermal treatment in the temperature interval from 400 °C to 850 °C and for times from 0.5 to 7.5 h. The chemical compositions of the silver dental amalgam alloy and the treated alloy were tested and microstructure analysis using optical and scanning electron microscopy was carried out. The phases were identified using energy disperse electron probe microanalysis. A mechanism for the mercury removal process from silver dental amalgam alloy is suggested.

  12. Removal of root filling materials.

    LENUS (Irish Health Repository)

    Duncan, H.F. Chong, B.S.

    2011-05-01

    Safe, successful and effective removal of root filling materials is an integral component of non-surgical root canal re-treatment. Access to the root canal system must be achieved in order to negotiate to the canal terminus so that deficiencies in the original treatment can be rectified. Since a range of materials have been advocated for filling root canals, different techniques are required for their removal. The management of commonly encountered root filling materials during non-surgical re-treatment, including the clinical procedures necessary for removal and the associated risks, are reviewed. As gutta-percha is the most widely used and accepted root filling material, there is a greater emphasis on its removal in this review.

  13. DETERMINATION OF TOTAL MERCURY IN FISH TISSUES USING PYROLYSIS ATOMIC ABSORPTION SPECTROMETRY WITH GOLD AMALGAMATION

    Science.gov (United States)

    A simple and rapid procedure for measuring total mercury in fish tissues is evaluated and compared with conventional techniques. Using an automated instrument incorporating combustion, preconcentration by amalgamation with gold, and atomic absorption spectrometry (AAS), mill...

  14. Solid Amalgam Composite Electrode as a New Sensor for the Determination of Biologically Active Compounds

    Czech Academy of Sciences Publication Activity Database

    Josypčuk, Bohdan; Navrátil, Tomáš; Lukina, A.; Pecková, K.; Barek, J.

    2007-01-01

    Roč. 52, č. 6 (2007), s. 897-910 ISSN 0009-2223 R&D Projects: GA ČR GA203/07/1195; GA MŠk(CZ) LC06035 Institutional research plan: CEZ:AV0Z40400503 Keywords : solid composite electrode * solid amalgam electrodes * solid amalgam composite electrode * voltammetry Subject RIV: CG - Electrochemistry Impact factor: 0.529, year: 2007

  15. Effect of Magnetic Resonance Imaging on Micro leakage of Amalgam Restorations

    International Nuclear Information System (INIS)

    Sayed, A.I.

    2013-01-01

    Objective: To authenticate whether exposure to magnetic resonance imaging (MRI) can cause micro leakage of amalgam restorations or not. Methods: This prospective in-vitro study study was conducted at Faculty of Oral and Dental Medicine, Cairo University. Thirty-six non-carious human teeth (18 premolars and 18 molars), (26 upper and 10 lower) were gathered from the Oral Surgery Department. Standard class V cavities with all margins in the enamel were made on the buccal and lingual aspects after surface debridement .Three groups of teeth were randomly assigned, each containing 12 teeth. Three types of amalgams were used, GS-80, Rupy Cap and Trend alloy. Each type of amalgams was randomly applied to one group. Each group was divided randomly into two equal categories, one was designed to be the control group and the other was scanned by a 1.5 Tesla MRI Scanner for approximately 5 minutes. Micro leakage was assessed in each group. Three amalgam specimens were scanned using 1.5 Tesla Optima MR360 Scanner .The three specimens were sticked to the superior aspect of the medium spine phantom (one specimen per scan) to induce magnetization transfer contrast to easily visualize these in vitro dental ware containing amalgam. The three specimens were scanned using the same Susceptibility Weighted Angiography (SWAN) technique in different orthogonal orientations (Axial, Coronal and Sagittal) to assess the amalgam induced artifacts during MRI scanning. The primary outcome measure was the micro leakage caused by different types of amalgams during MRI scanning; the second outcome measure was the artifacts that may be encountered by different types of amalgams during MRI scanning .

  16. A 24-month evaluation of amalgam and resin-based composite restorations

    DEFF Research Database (Denmark)

    McCracken, Michael S; Gordan, Valeria V; Litaker, Mark S

    2013-01-01

    Knowing which factors influence restoration longevity can help clinicians make sound treatment decisions. The authors analyzed data from The National Dental Practice-Based Research Network to identify predictors of early failures of amalgam and resin-based composite (RBC) restorations.......Knowing which factors influence restoration longevity can help clinicians make sound treatment decisions. The authors analyzed data from The National Dental Practice-Based Research Network to identify predictors of early failures of amalgam and resin-based composite (RBC) restorations....

  17. Central centrifugal cicatricial alopecia amalgamated with alopecia areata: immunologic findings

    Directory of Open Access Journals (Sweden)

    Ana Maria Abreu Velez

    2014-07-01

    Full Text Available Introduction: Both scarring and non-scarring alopecias exist; however, rare cases demonstrate features of both classes. Case Report: We describe an interesting alopecia case with amalgamated clinical, histologic and immunopathologic features of scarring and non-scarring alopecia. Specifically, the case displays combined features of alopecia areata (AA and of central centrifugal cicatricial alopecia (CCCA. A 36 year old female presented with symmetric, round, patchy hair loss on her scalp. Methods: Biopsies for hematoxylin and eosin (H&E examination, as well as for special stains, direct immunofluorescence (DIF and immunohistochemistry (IHC were performed. Results: The H&E biopsy revealed focally diminished hair follicular units, and sebaceous gland damage. Perifollicular concentric fibrosis was confirmed by Verhoeff elastin special staining. Antibodies to micelles were noted. Positive IHC staining for CD4, CD8, CD45 and multiple proteases and protease inhibitors was noted around selected follicular unit remnants. Conclusion: We present a rare alopecia, combining histologic features of CCCA with additional, selected immunologic features of AA.

  18. Kinetic and thermodynamic study of lithium ternary amalgams in contact with solvated lithium hydroxide

    International Nuclear Information System (INIS)

    Cordova M, M.

    1991-12-01

    Lithium amalgams are used on lithium isotope separation, the process has been studied in its different parameters, but there is no information on the isotopic separation in the presence of ternary metals diluted in the amalgam. The latest voltammetric technique developed for trace analysis is used for the study, to determine the effects of the presence of cadmium, which has been selected on compatibility criteria with the system, in the intermetallic structures of the amalgam. The differential pulse anodic stripping voltammetry indicates the presence of an intermetallic persistent structure after the potassium and lithium oxidation. This structure has a slow formation and destruction rate, with an anionic character, which accounts for the oxidation potential displacement of the amalgamated metals. The activation energy results of amalgam decomposition reaction in contact with water, allows to establish the intermetallic effects on this reaction, raising the energy of the activated state, on condition that there were time to form it. A reaction mechanism is proposed that agrees with these results. The study of the isotopic composition indicates that the intermetallic species affect the thermodynamic equilibrium between the phases in contact. The measurements of the system's isotopic composition do not give exact values for the separation factors, but they establish a difference in the sign of enthalpies of the isotopic equilibria. The enthalpy for the isotopic exchange for the binary amalgam is negative, with a value that agrees with those in the literature. Nevertheless, those of the ternary systems are positive, indicating an endothermic character process. (author)

  19. Comparison of shear bond strength of amalgam bonded to primary and permanent dentin

    Directory of Open Access Journals (Sweden)

    Mahdi S

    2008-06-01

    Full Text Available Amalgam′s non-adhesive characteristics necessitate cavity preparations incorporating retentive features, which often require the removal of non-carious tooth structure. Use of adhesives beneath amalgam restorations, would be helpful to overcome this disadvantage. This study was undertaken to compare the mean shear bond strength of amalgam bonded to primary and permanent dentin, to evaluate the efficacy of amalgam adhesives in pediatric dentistry.27 primary and 28 permanent posterior teeth with intact buccal or lingual surfaces were grounded to expose dentin and wet-polished with 400-grit silicone carbide paper. Scotchbond Multi Purpose Plus adhesive system was applied to the dentin surfaces and light cured. Amalgam was condensed onto the treated dentin through a plastic mold.shear bond strength testing was done using an Instron Universal testing machine, at a crosshead speed of 0.5 mm/min.The data were analyzed by independent samples t-test The difference among the two groups was not statistically significant (p>0.05 Bonded amalgam showed the same level of bond strength to primary and permanent dentin; so, application of amalgam bonding agents in pediatric dentistry can be recommended.

  20. Sodium fill of FFTF

    International Nuclear Information System (INIS)

    Waldo, J.B.; Greenwell, R.K.; Keasling, T.A.; Collins, J.R.; Klos, D.B.

    1980-02-01

    With construction of the Fast Flux Test Facility (FFTF) completed, the first major objective in the startup program was to fill the sodium systems. A sodium fill sequence was developed to match construction completion, and as systems became available, they were inerted, preheated, and filled with sodium. The secondary sodium systems were filled first while dry refueling system testing was in progress in the reactor vessel. The reactor vessel and the primary loops were filled last. This paper describes the methods used and some of the key results achieved for this major FFTF objective

  1. Influence of dental filling material type on the concentration of interleukin 9 in the samples of gingival crevicular fluid

    Directory of Open Access Journals (Sweden)

    Stefanović Vladimir

    2016-01-01

    Full Text Available Background/Aim. Several cytokines and lymphokines (IL1β, ENA78, IL6, TNFα, IL8 and S100A8 are expressed during dental pulp inflammation. Analysis of gingival crevicu-lar fluid (GCF offers a non-invasive means of studying gen-eral host response in oral cavity. Although GCF levels of various mediators could reflect the state of inflammation both in dental pulp and gingiva adjacent to a tooth, GCF samples of those without significant gingivitis could be inter-preted as reflection of pulpal process. The aim of this study was to investigate IL9 GCF values in patients with dental car-ies and to assess possible influence of various dental fillings materials on local IL9 production. Methods. The study group included 90 patients, aged 18–70, with inclusion and exclusion criteria in the prospective clinical study. Of the 6 types of material used for the restoration of prepared cavities, 3 were intended for temporary and 3 for definitive restora-tion. According to dental fillings weight, all the participants were divided into 3 groups: those with fillings lighter than 0.50 g, those with 0.50–1.00 g, and those with fillings heavier than 1.00 g. Samples were taken from gingival sulcus using the filter paper technique. Clinical parameters were deter-mined by bleeding index, plaque index (Silness-Lou, 0–3, gingival index (0–3, and gingival sulcus depth. Cytokine con-centrations were assessed using commercially available cy-tomix. Results. According to the weight of dental fillings, there was a clear decreament trend of IL9 values meaning that dental defects greater than 1.00 g of dental filling were associated with lower GCF IL9 concentration. The IL9 val-ues correlated with the degree of gingival index and depth of gingival sulcus, being higher with more advanced gingivitis and more pronounced anatomical changes in the tooth edge. Different filling materials exerted various local IL9 responses. Zink polycarbonate cement and amalgam fillings induced

  2. Preparation of dental amalgam and spectral diagnosis of mercury in plasmas-laser in the region of 250 nm – 850 nm

    International Nuclear Information System (INIS)

    Ossa, A De la; Pacheco, P; Sarmiento, R

    2013-01-01

    In this paper we presents results of the spectral study of plasmas-laser of dental amalgam by technique Laser-induced Breakdown Spectroscopy (LIBS). Plasmas were generated focusing the beam of a Nd: YAG laser on the matrix of the mixture Ag-Sn-Cu and on amalgams with different proportions of mercury (3:2, 5:2, 6:2). Based on the spectral results and reported atomic parameters, became estimation of electron temperature plasmas- laser and their behavior with the concentration of Hg. The estimated values of the electron temperature for the respective proportions were 20 846 K, 19 139 K and 16 872 K, using the distribution of population of Boltzmann energy levels associated with spectral lines, considering conditions Local Thermodinamic Equilibrium (LTE) of plasmas

  3. Quantification of Hg excretion and distribution in biological samples of mercury-dental-amalgam users and its correlation with biological variables.

    Science.gov (United States)

    Gul, Nayab; Khan, Sardar; Khan, Abbas; Nawab, Javed; Shamshad, Isha; Yu, Xinwei

    2016-10-01

    This is the first study conducted to quantify the excretion and distribution of mercury (Hg) with time (days) in the biological samples collected from Hg dental amalgam users (MDA). The individuals, with Hg-based dental filling were selected, and their biological samples (red blood cells (RBCs), plasma, urine, hair, and nails) were collected on first, third, and 12th day of fillings. The concentrations of Hg observed in the biological samples of MDA were also correlated with the biological variables such as age, weight, restoration, fish consumption, number, and surface area of fillings. The concentrations of Hg in the biological samples of MDA were found 6-8 times higher than the non-amalgam users (control). The concentrations of Hg in the RBCs (4.39 μg/L), plasma (3.02 μg/L), and urine (22.5 μg/L) on first day of filling were found comparatively higher than the concentrations observed on third day (2.15, 1.46, and 12.3 μg/L for RBCs, plasma, urine, respectively) and 12th day (3.05, 2.5, 9.12 μg/L for RBCs, plasma, urine, respectively), while Hg concentrations were found lower in the hair and nails on third day of fillings (1.53 μg/g for hair and 2.35 μg/g for nails) as compared to the 12th day (2.95 μg/g for hair and 3.5 μg/g for nails). The correlations were found significant (p ˂ 0.05) between Hg concentrations in the biological samples of MDA and biological variables (the number of restoration, fish consumption, number, and surface area of fillings), while no significant (p ˃ 0.05) correlations were observed for Hg concentrations in the biological samples with age and weight of MDA. These observations unveil the fact that the use of Hg-based dental filling is the undesirable exposure to Hg which should be replaced by composite (a safer filling material).

  4. Hydrogen Filling Station

    Energy Technology Data Exchange (ETDEWEB)

    Boehm, Robert F; Sabacky, Bruce; Anderson II, Everett B; Haberman, David; Al-Hassin, Mowafak; He, Xiaoming; Morriseau, Brian

    2010-02-24

    Hydrogen is an environmentally attractive transportation fuel that has the potential to displace fossil fuels. The Freedom CAR and Freedom FUEL initiatives emphasize the importance of hydrogen as a future transportation fuel. Presently, Las Vegas has one hydrogen fueling station powered by natural gas. However, the use of traditional sources of energy to produce hydrogen does not maximize the benefit. The hydrogen fueling station developed under this grant used electrolysis units and solar energy to produce hydrogen fuel. Water and electricity are furnished to the unit and the output is hydrogen and oxygen. Three vehicles were converted to utilize the hydrogen produced at the station. The vehicles were all equipped with different types of technologies. The vehicles were used in the day-to-day operation of the Las Vegas Valley Water District and monitoring was performed on efficiency, reliability and maintenance requirements. The research and demonstration utilized for the reconfiguration of these vehicles could lead to new technologies in vehicle development that could make hydrogen-fueled vehicles more cost effective, economical, efficient and more widely used. In order to advance the development of a hydrogen future in Southern Nevada, project partners recognized a need to bring various entities involved in hydrogen development and deployment together as a means of sharing knowledge and eliminating duplication of efforts. A road-mapping session was held in Las Vegas in June 2006. The Nevada State Energy Office, representatives from DOE, DOE contractors and LANL, NETL, NREL were present. Leadership from the National hydrogen Association Board of Directors also attended. As a result of this session, a roadmap for hydrogen development was created. This roadmap has the ability to become a tool for use by other road-mapping efforts in the hydrogen community. It could also become a standard template for other states or even countries to approach planning for a hydrogen

  5. Uptake and accumulation of mercury from dental amalgam in the common goldfish, Carassius auratus

    International Nuclear Information System (INIS)

    Kennedy, C.J.

    2003-01-01

    Exposure of fish to concentrations of dental amalgam typically found in waste discharge leads to mercury accumulation in tissues. - In this study, the bioavailability and accumulation of mercury from external environmental exposure to mixed, cured, milled, sieved and proportioned dental amalgam was examined in the common goldfish, Carassius auratus. Fish were exposed to dental amalgam (particle size range from <0.10 to 3.15 mm) in order to represent the particle size and distribution of that found within the typical dental office wastewater discharge stream. Experimental amalgam water loadings were 0 g/l, 0.5 g/l and 1 g/l in glass aquaria at 15 deg. C for 28 days. Fish tissues were sampled at 5 min and 28 days of exposure, and the liver, brain, muscle and whole body analyzed for total mercury using cold vapor atomic fluorescence spectroscopy. Mercury was found in several tissues examined and generally increased with exposure to higher amounts of dental amalgam. The highest levels were found in the whole body (17.68±5.73 μg/g) followed by the liver (0.80±0.16 μg/g) and muscle (0.47±0.16 μg/g). The lowest concentrations were seen in the brain (0.28±0.19 μg/g). Compared to controls, concentrations in the whole body, muscle and liver in fish exposed for 28 days to the highest concentration of amalgam were 200-, 233-, and 40-fold higher, respectively. This study shows that mercury from an environmental exposure to representative samples of dental amalgam typically found within the dental wastewater discharge stream is bioavailable to fish and may accumulate in internal tissues

  6. Do Dental Resin Composites Accumulate More Oral Biofilms and Plaque than Amalgam and Glass Ionomer Materials?

    Directory of Open Access Journals (Sweden)

    Ning Zhang

    2016-11-01

    Full Text Available A long-time drawback of dental composites is that they accumulate more biofilms and plaques than amalgam and glass ionomer restorative materials. It would be highly desirable to develop a new composite with reduced biofilm growth, while avoiding the non-esthetics of amalgam and low strength of glass ionomer. The objectives of this study were to: (1 develop a protein-repellent composite with reduced biofilms matching amalgam and glass ionomer for the first time; and (2 investigate their protein adsorption, biofilms, and mechanical properties. Five materials were tested: A new composite containing 3% of protein-repellent 2-methacryloyloxyethyl phosphorylcholine (MPC; the composite with 0% MPC as control; commercial composite control; dental amalgam; resin-modified glass ionomer (RMGI. A dental plaque microcosm biofilm model with human saliva as inoculum was used to investigate metabolic activity, colony-forming units (CFU, and lactic acid production. Composite with 3% MPC had flexural strength similar to those with 0% MPC and commercial composite control (p > 0.1, and much greater than RMGI (p < 0.05. Composite with 3% MPC had protein adsorption that was only 1/10 that of control composites (p < 0.05. Composite with 3% MPC had biofilm CFU and lactic acid much lower than control composites (p < 0.05. Biofilm growth, metabolic activity and lactic acid on the new composite with 3% MPC were reduced to the low level of amalgam and RMGI (p > 0.1. In conclusion, a new protein-repellent dental resin composite reduced oral biofilm growth and acid production to the low levels of non-esthetic amalgam and RMGI for the first time. The long-held conclusion that dental composites accumulate more biofilms than amalgam and glass ionomer is no longer true. The novel composite is promising to finally overcome the major biofilm-accumulation drawback of dental composites in order to reduce biofilm acids and secondary caries.

  7. Uptake and accumulation of mercury from dental amalgam in the common goldfish, Carassius auratus

    Energy Technology Data Exchange (ETDEWEB)

    Kennedy, C.J

    2003-03-01

    Exposure of fish to concentrations of dental amalgam typically found in waste discharge leads to mercury accumulation in tissues. - In this study, the bioavailability and accumulation of mercury from external environmental exposure to mixed, cured, milled, sieved and proportioned dental amalgam was examined in the common goldfish, Carassius auratus. Fish were exposed to dental amalgam (particle size range from <0.10 to 3.15 mm) in order to represent the particle size and distribution of that found within the typical dental office wastewater discharge stream. Experimental amalgam water loadings were 0 g/l, 0.5 g/l and 1 g/l in glass aquaria at 15 deg. C for 28 days. Fish tissues were sampled at 5 min and 28 days of exposure, and the liver, brain, muscle and whole body analyzed for total mercury using cold vapor atomic fluorescence spectroscopy. Mercury was found in several tissues examined and generally increased with exposure to higher amounts of dental amalgam. The highest levels were found in the whole body (17.68{+-}5.73 {mu}g/g) followed by the liver (0.80{+-}0.16 {mu}g/g) and muscle (0.47{+-}0.16 {mu}g/g). The lowest concentrations were seen in the brain (0.28{+-}0.19 {mu}g/g). Compared to controls, concentrations in the whole body, muscle and liver in fish exposed for 28 days to the highest concentration of amalgam were 200-, 233-, and 40-fold higher, respectively. This study shows that mercury from an environmental exposure to representative samples of dental amalgam typically found within the dental wastewater discharge stream is bioavailable to fish and may accumulate in internal tissues.

  8. Electrochemical Biosensors Based on Enzymatic Reactors Filled by Various Types of Silica and Amalgam Powders for Measurements in Flow Systems

    Czech Academy of Sciences Publication Activity Database

    Josypčuk, Oksana; Barek, J.; Josypčuk, Bohdan

    2016-01-01

    Roč. 28, č. 12 (2016), s. 3028-3038 ISSN 1040-0397 R&D Projects: GA ČR(CZ) GA15-03139S Institutional support: RVO:61388955 Keywords : electrochemical biosensors * enzymatic reactor * silica powders Subject RIV: CG - Electrochemistry Impact factor: 2.851, year: 2016

  9. Progressive Amalgamation of Building Clusters for Map Generalization Based on Scaling Subgroups

    Directory of Open Access Journals (Sweden)

    Xianjin He

    2018-03-01

    Full Text Available Map generalization utilizes transformation operations to derive smaller-scale maps from larger-scale maps, and is a key procedure for the modelling and understanding of geographic space. Studies to date have largely applied a fixed tolerance to aggregate clustered buildings into a single object, resulting in the loss of details that meet cartographic constraints and may be of importance for users. This study aims to develop a method that amalgamates clustered buildings gradually without significant modification of geometry, while preserving the map details as much as possible under cartographic constraints. The amalgamation process consists of three key steps. First, individual buildings are grouped into distinct clusters by using the graph-based spatial clustering application with random forest (GSCARF method. Second, building clusters are decomposed into scaling subgroups according to homogeneity with regard to the mean distance of subgroups. Thus, hierarchies of building clusters can be derived based on scaling subgroups. Finally, an amalgamation operation is progressively performed from the bottom-level subgroups to the top-level subgroups using the maximum distance of each subgroup as the amalgamating tolerance instead of using a fixed tolerance. As a consequence of this step, generalized intermediate scaling results are available, which can form the multi-scale representation of buildings. The experimental results show that the proposed method can generate amalgams with correct details, statistical area balance and orthogonal shape while satisfying cartographic constraints (e.g., minimum distance and minimum area.

  10. Facilitating organizational mergers: amalgamation of community care access centres.

    Science.gov (United States)

    Mercer, Kevin

    2008-01-01

    The development of 14 Local Health Integration Networks (LHINs) in Ontario necessitated the re-organization of Community Care Access Centres (CCACs). The achievement of LHIN objectives was contingent upon the organizations responsible for home and long-term care placement being aligned within the LHIN geographic boundaries. This re-alignment required 42 provincial organizations to re-structure, integrate and reduce to 14. This project was focused on the amalgamation of two CCACs in the Waterloo Wellington LHIN. Both were distinctly different due to their organizational evolution, the composition of the region and leadership approach. The different organizational cultures, if not managed properly, could result in a derailing of several current projects that were underway and were also key to the overall health system transformation agenda. A literature search provided a plethora of critiques of organizational change approaches and practical suggestions. Of particular relevance was a report to the Royal Commission on Health Care in 2002 that authenticates the dismal success in health care to meet change objectives. The project included a joint planning day for the leadership teams of the two organizations followed by an Organizational Readiness Assessment conducted by the Canadian Council on Health Services Accreditation (CCHSA). Both activities brought the leadership and staff of Waterloo and Wellington together, started the integration process and solicited staff participation. A follow-up survey of the leadership teams revealed the effectiveness of the project in advancing integration between the two organizations and recognizing organizational cultural differences. The CCHSA Organizational Readiness Assessment process was viewed as an effective means for advancing the integration of the two organizations, particularly as it relates to allowing the staff groups to define for themselves the benefits of the merger. The lack of hard evidence on the benefits of a

  11. Decomposing one-relator products of cyclic groups into free products with amalgamation

    International Nuclear Information System (INIS)

    Benyash-Krivets, V V

    1998-01-01

    The problem of the decomposition of one-relator products of cyclics into non-trivial free products with amalgamation is considered. Two theorems are proved, one of which is as follows. Let G= 2n =R m (a,b)=1>, where n≥0, m≥2, and R(a,b) is a cyclically reduced word containing b in the free group on a and b. Then G is a non-trivial free product with amalgamation. One consequence of this theorem is a proof of the conjecture of Fine, Levin, and Rosenberger that each two-generator one-relator group with torsion is a non-trivial free product with amalgamation

  12. Taguchi optimization: Case study of gold recovery from amalgamation tailing by using froth flotation method

    Science.gov (United States)

    Sudibyo, Aji, B. B.; Sumardi, S.; Mufakir, F. R.; Junaidi, A.; Nurjaman, F.; Karna, Aziza, Aulia

    2017-01-01

    Gold amalgamation process was widely used to treat gold ore. This process produces the tailing or amalgamation solid waste, which still contains gold at 8-9 ppm. Froth flotation is one of the promising methods to beneficiate gold from this tailing. However, this process requires optimal conditions which depends on the type of raw material. In this study, Taguchi method was used to optimize the optimum conditions of the froth flotation process. The Taguchi optimization shows that the gold recovery was strongly influenced by the particle size which is the best particle size at 150 mesh followed by the Potassium amyl xanthate concentration, pH and pine oil concentration at 1133.98, 4535.92 and 68.04 gr/ton amalgamation tailing, respectively.

  13. Mercury content in amalgam tattoos of human oral mucosa and its relation to local tissue reactions

    Energy Technology Data Exchange (ETDEWEB)

    Forsell, M.; Larsson, B.; Ljungqvist, A.; Carlmark, B.; Johansson, O

    1998-02-01

    Mucosal biopsies from 48 patients with and 9 without amalgam tattoos were analysed with respect to their mercury content, distribution of mercury in the tissue, and histological tissue reactions. The distribution of mercury was assessed by auto-metallography (AMG), a silver amplification technique. The mercury content was determined by energy dispersive X-ray fluorescence (EDXRF), a multielemental analysis. Mercury was observed in connective tissue where it was confined to fibroblasts and macrophages, in vessel walls and in structures with the histological character of nerve fibres. A correlation was found between the histopathological tissue reaction, the type of mercury deposition, the intensity of the AMG reaction, and the mercury content. Mercury was also found in patients with amalgam dental fittings but without amalgam tattoos. (au) 24 refs.

  14. Mercury content in amalgam tattoos of human oral mucosa and its relation to local tissue reactions

    International Nuclear Information System (INIS)

    Forsell, M.; Larsson, B.; Ljungqvist, A.; Carlmark, B.; Johansson, O.

    1998-01-01

    Mucosal biopsies from 48 patients with and 9 without amalgam tattoos were analysed with respect to their mercury content, distribution of mercury in the tissue, and histological tissue reactions. The distribution of mercury was assessed by auto-metallography (AMG), a silver amplification technique. The mercury content was determined by energy dispersive X-ray fluorescence (EDXRF), a multielemental analysis. Mercury was observed in connective tissue where it was confined to fibroblasts and macrophages, in vessel walls and in structures with the histological character of nerve fibres. A correlation was found between the histopathological tissue reaction, the type of mercury deposition, the intensity of the AMG reaction, and the mercury content. Mercury was also found in patients with amalgam dental fittings but without amalgam tattoos. (au)

  15. Mercury release from dental amalgam restorations after magnetic resonance imaging and following mobile phone use.

    Science.gov (United States)

    Mortazavi, S M J; Daiee, E; Yazdi, A; Khiabani, K; Kavousi, A; Vazirinejad, R; Behnejad, B; Ghasemi, M; Mood, M Balali

    2008-04-15

    In the 1st phase of this study, thirty patients were investigated. Five milliliter stimulated saliva was collected just before and after MRI. The magnetic flux density was 0.23 T and the duration of exposure of patients to magnetic field was 30 minutes. In the 2nd phase, fourteen female healthy University students who had not used mobile phones before the study and did not have any previous amalgam restorations were investigated. Dental amalgam restoration was performed for all 14 students. Their urine samples were collected before amalgam restoration and at days 1, 2, 3 and 4 after restoration. The mean +/- SD saliva Hg concentrations of the patients before and after MRI were 8.6 +/- 3.0 and 11.3 +/- 5.3 microg L(-1), respectively (p mobile phone. The mean +/- SE urinary Hg concentrations of the students who used mobile phones were 2.43 +/- 0.25, 2.71 +/- 0.27, 3.79 +/- 0.25, 4.8 +/- 0.27 and 4.5 +/- 0.32 microg L(-1) before the amalgam restoration and at days 1, 2, 3 and 4, respectively. Whereas the respective Hg concentrations in the controls, were 2.07 +/- 0.22, 2.34 +/- 0.30, 2.51 +/- 0.25, 2.66 +/- 0.24 and 2.76 +/- 0.32 microg L(-1). It appears that MRI and microwave radiation emitted from mobile phones significantly release mercury from dental amalgam restoration. Further research is needed to clarify whether other common sources of electromagnetic field exposure may cause alterations in dental amalgam and accelerate the release of mercury.

  16. The Distribution of Mutans Streptococci in Plaque on the margin of Amalgam, on the Enamel, and on the Surface of Amalgam Restoration

    Directory of Open Access Journals (Sweden)

    Soeherwin Mangundjaja

    2015-10-01

    Full Text Available The aim of the study was to evaluate the level of distribution of mutans streptococci on the margin of amalgam restoration, compared with that on the enamel and on the surface of restoration. It is assumed that the level of distribution of mutans streptococci on the margin will be able to influence the presence of secondary caries. In this study the first molars of 20 patients were treated with amalgam restoration. The mutans streptococci was measured as the percentage of total CFU count in the plaque. The results showed a mean count of 108.8 (SD= 55.2 of mutans streptococci in the margin; 97.7 (SD=63.5 on the enamel; and 61.4 (SD=32.4 on the surface of amalgam restoration. It seems that the level of mutans streptococci on the margin is higher than those on the enamel (p=0.006 as well as higher than those on the surface of (p=0.031. It is suggested that elevated level of mutans streptococci on the margin can indicate risk to secondary caries.

  17. Comparison of antibacterial activities of root-end filling materials by an agar diffusion assay and Alamar blue assay

    Directory of Open Access Journals (Sweden)

    Tsui-Hsien Huang

    2012-12-01

    Conclusion: We concluded that both the agar diffusion test and Alamar blue assay gave comparable findings of assessing the antimicrobial activity present in root-end filling materials. No antimicrobial activity was detected for mineral trioxide aggregate, calcium silicate cement, or amalgam after coming into contact with S. mutans, S. sanguinis and E. coli. IRM showed high antimicrobial activity against both S. sanguinis and E. coli.

  18. Filling a Conical Cavity

    Science.gov (United States)

    Nye, Kyle; Eslam-Panah, Azar

    2016-11-01

    Root canal treatment involves the removal of infected tissue inside the tooth's canal system and filling the space with a dense sealing agent to prevent further infection. A good root canal treatment happens when the canals are filled homogeneously and tightly down to the root apex. Such a tooth is able to provide valuable service for an entire lifetime. However, there are some examples of poorly performed root canals where the anterior and posterior routes are not filled completely. Small packets of air can be trapped in narrow access cavities when restoring with resin composites. Such teeth can cause trouble even after many years and lead the conditions like acute bone infection or abscesses. In this study, the filling of dead-end conical cavities with various liquids is reported. The first case studies included conical cavity models with different angles and lengths to visualize the filling process. In this investigation, the rate and completeness at which a variety of liquids fill the cavity were observed to find ideal conditions for the process. Then, a 3D printed model of the scaled representation of a molar with prepared post spaces was used to simulate the root canal treatment. The results of this study can be used to gain a better understanding of the restoration for endodontically treated teeth.

  19. The use of copper solid amalgam electrodes for determination of the pesticide thiram

    Czech Academy of Sciences Publication Activity Database

    Nováková, Kateřina; Navrátil, Tomáš; Jaklová Dytrtová, Jana; Chýlková, J.

    2013-01-01

    Roč. 17, č. 6 (2013), s. 1517-1528 ISSN 1432-8488 R&D Projects: GA ČR(CZ) GAP208/12/1645; GA ČR GP13-21409P Institutional support: RVO:61388955 ; RVO:61388963 Keywords : Tetramethylthiuram disulfide * amalgam * voltammetry Subject RIV: CG - Electrochemistry Impact factor: 2.234, year: 2013

  20. Flow electrochemical biosensors based on enzymatic porous reactor and tubular detector of silver solid amalgam

    Czech Academy of Sciences Publication Activity Database

    Josypčuk, Bohdan; Barek, J.; Josypčuk, Oksana

    2013-01-01

    Roč. 778, MAY 2013 (2013), s. 24-30 ISSN 0003-2670 R&D Projects: GA ČR GAP206/11/1638 Institutional support: RVO:61388955 Keywords : flow analysis * amperometry * silver solid amalgam Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 4.517, year: 2013

  1. A novel paste electrode based on a silver solid amalgam and an organic pasting liquid

    Czech Academy of Sciences Publication Activity Database

    Daňhel, A.; Josypčuk, Bohdan; Vyskočil, V.; Zima, J.; Barek, J.

    2011-01-01

    Roč. 656, 1-2 (2011), s. 218-222 ISSN 1572-6657 R&D Projects: GA MŠk(CZ) LC06063; GA AV ČR IAA400400806 Institutional research plan: CEZ:AV0Z40400503 Keywords : voltammetry * paste electrode * silver amalgam Subject RIV: CG - Electrochemistry Impact factor: 2.905, year: 2011

  2. A Novel Voltammetric Method for the Determination of Maleic Acid Using Silver Amalgam Paste Electrode

    Czech Academy of Sciences Publication Activity Database

    Niaz, A.; Fischer, J.; Barek, J.; Josypčuk, Bohdan; Sirajuddin, C.; Bhanger, M. I.

    2009-01-01

    Roč. 21, č. 15 (2009), s. 1719-1722 ISSN 1040-0397 R&D Projects: GA MŠk(CZ) LC06035; GA ČR GA203/07/1195 Institutional research plan: CEZ:AV0Z40400503 Keywords : voltammetry * maleic acid * silver amalgam paste electrode Subject RIV: CG - Electrochemistry Impact factor: 2.630, year: 2009

  3. Voltametric Determination of Adenine, Guanine and DNA Using Liquid Mercury Free Polished Silver Solid Amalgam Electrode

    Czech Academy of Sciences Publication Activity Database

    Fadrná, Renata; Josypčuk, Bohdan; Fojta, Miroslav; Navrátil, Tomáš; Novotný, Ladislav

    2004-01-01

    Roč. 37, č. 3 (2004), s. 399-413 ISSN 0003-2719 R&D Projects: GA AV ČR KSK4040110 Grant - others:GIT(AR) 101/02/U111/CZ Keywords : voltammetry * DNA * polished silver solid amalgam electrode Subject RIV: CG - Electrochemistry Impact factor: 1.165, year: 2004

  4. Silver Solid Amalgam Electrode as a Tool for Monitoring the Electrochemical Reduction of Hydroxocobalamin

    Czech Academy of Sciences Publication Activity Database

    Bandžuchová, L.; Šelešovská, R.; Navrátil, Tomáš; Chýlková, J.

    2013-01-01

    Roč. 25, č. 1 (2013), s. 213-222 ISSN 1040-0397 R&D Projects: GA ČR GAP206/11/1638; GA ČR(CZ) GAP208/12/1645 Institutional support: RVO:61388955 Keywords : cobalamin * hanging mercury drop electrode * silver solid amalgam electrode Subject RIV: CG - Electrochemistry Impact factor: 2.502, year: 2013

  5. Application of silver solid amalgam electrode for determination of formamidine amitraz

    Czech Academy of Sciences Publication Activity Database

    Nováková, Kateřina; Hrdlička, V.; Navrátil, Tomáš; Harvila, M.; Zima, J.; Barek, J.

    2016-01-01

    Roč. 147, č. 1 (2016), s. 181-189 ISSN 0026-9247 R&D Projects: GA ČR(CZ) GAP208/12/1645 Institutional support: RVO:61388955 Keywords : amitraz * pesticide * silver solid amalgam electrode Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.282, year: 2016

  6. Voltammetric monitoring of electrochemical reduction of riboflavin using silver solid amalgam electrodes

    Czech Academy of Sciences Publication Activity Database

    Bandžuchová, L.; Šelešovská, R.; Navrátil, Tomáš; Chýlková, J.; Novotný, L.

    2012-01-01

    Roč. 75, July 2012 (2012), s. 316-324 ISSN 0013-4686 R&D Projects: GA AV ČR IAA400400806; GA ČR GAP208/12/1645; GA ČR GAP206/11/1638 Institutional support: RVO:61388955 Keywords : riboflavin * determination * amalgam electrode Subject RIV: CG - Electrochemistry Impact factor: 3.777, year: 2012

  7. When Old and New Regionalism Collide: Deinstitutionalization of Regions and Resistance Identity in Municipality Amalgamations

    Science.gov (United States)

    Zimmerbauer, Kaj; Paasi, Anssi

    2013-01-01

    Regions as well as their identities and borders are social and discursive constructs that are produced and removed in contested, historically contingent and context-bound processes of institutionalization and deinstitutionalization. This article studies the deinstitutionalization of regions in the context of municipality amalgamations and the…

  8. Electrolytic method for the production of lithium using a lithium-amalgam electrode

    Science.gov (United States)

    Cooper, John F.; Krikorian, Oscar H.; Homsy, Robert V.

    1979-01-01

    A method for recovering lithium from its molten amalgam by electrolysis of the amalgam in an electrolytic cell containing as a molten electrolyte a fused-salt consisting essentially of a mixture of two or more alkali metal halides, preferably alkali metal halides selected from lithium iodide, lithium chloride, potassium iodide and potassium chloride. A particularly suitable molten electrolyte is a fused-salt consisting essentially of a mixture of at least three components obtained by modifying an eutectic mixture of LiI-KI by the addition of a minor amount of one or more alkali metal halides. The lithium-amalgam fused-salt cell may be used in an electrolytic system for recovering lithium from an aqueous solution of a lithium compound, wherein electrolysis of the aqueous solution in an aqueous cell in the presence of a mercury cathode produces a lithium amalgam. The present method is particularly useful for the regeneration of lithium from the aqueous reaction products of a lithium-water-air battery.

  9. Study of complex amalgams containing alkali metals by method of broken thermometric titration

    International Nuclear Information System (INIS)

    Filippova, L.M.; Zebreva, A.I.; Espenbetov, A.A.

    1977-01-01

    Complex potassium-cadmium and sodium-cadmium amalgams containing different amounts of the alkali metal nad cadmium have been studied by thermometric titration with mercury. The experiments have been carried out in argon atmosphere at 25 deg C. As evidenced by the titration of sodium-cadmium amalgams, in the range of concentrations studied (Csub(Na)=0.71-2.95, Csub(Cd)=4.38-6.45 g-at/lHg) no solid phase is formed in them. Potassium-cadmium amalgams where the metals content is no higher than their individual solubility in mercury, display, when being mercury-titrated, negative heat effects due to solid phase formation. An estimation is made of the solid phase composition, its solubility in mercury and the heat of dissolution. The solid phase appearing in complex K-Cd amalgams is likely to contain K and Cd in a ratio 1:1 its conventional solubility product is 5.4 g-at/l Hg, and the heat of dissolution in mercury at 25 deg is -21 +-4 kJ/g-at

  10. Voltammetric determination of sodium anthraquinone-2-sulfonate using silver solid amalgam electrodes

    Czech Academy of Sciences Publication Activity Database

    Skalová, Štěpánka; Navrátil, Tomáš; Barek, J.; Vyskočil, V.

    2017-01-01

    Roč. 148, č. 3 (2017), s. 577-583 ISSN 0026-9247 Institutional support: RVO:61388955 Keywords : Anthraquinone * Drugs * Silver solid amalgam electrode * Voltammetry Subject RIV: CG - Electrochemistry OBOR OECD: Electrochemistry (dry cells, batteries, fuel cells, corrosion metals, electrolysis) Impact factor: 1.282, year: 2016

  11. Application of Copper Solid Amalgam Electrode for Determination of Fungicide Tebuconazole

    Czech Academy of Sciences Publication Activity Database

    Nováková, Kateřina; Navrátil, Tomáš; Jaklová Dytrtová, Jana; Chýlková, J.

    2013-01-01

    Roč. 8, č. 1 (2013), s. 1-16 ISSN 1452-3981 R&D Projects: GA ČR GAP206/11/1638; GA ČR(CZ) GAP208/12/1645 Institutional support: RVO:61388955 ; RVO:61388963 Keywords : tebuconazole * fungicide * copper solid amalgam electrode Subject RIV: CG - Electrochemistry Impact factor: 1.956, year: 2013

  12. Combined Voltammetric-Potentiometric Sensor with the Silver Solid Amalgam Link for Electroanalytical Measurements

    Czech Academy of Sciences Publication Activity Database

    Josypčuk, Bohdan; Novotný, Ladislav

    2002-01-01

    Roč. 14, č. 24 (2002), s. 1739-1741 ISSN 1040-0397 R&D Projects: GA ČR GV204/97/K084 Institutional research plan: CEZ:AV0Z4040901 Keywords : combined voltammetric-potentiometric sensors * solid amalgam Subject RIV: CG - Electrochemistry Impact factor: 1.783, year: 2002

  13. An Empirical Consideration of a Balanced Amalgamation of Learning Strategies in Graduate Introductory Statistics Classes

    Science.gov (United States)

    Vaughn, Brandon K.

    2009-01-01

    This study considers the effectiveness of a "balanced amalgamated" approach to teaching graduate level introductory statistics. Although some research stresses replacing traditional lectures with more active learning methods, the approach of this study is to combine effective lecturing with active learning and team projects. The results of this…

  14. Cathodic Stripping Voltammetry of Cysteine Using Silver and Copper Solid Amalgam Electrodes

    Czech Academy of Sciences Publication Activity Database

    Josypčuk, Bohdan; Novotný, Ladislav

    2002-01-01

    Roč. 56, č. 5 (2002), s. 971-976 ISSN 0039-9140 R&D Projects: GA ČR GV204/97/K084 Institutional research plan: CEZ:AV0Z4040901 Keywords : silver or copper solid amalgam electrode * cysteine * voltammetry Subject RIV: CG - Electrochemistry Impact factor: 2.054, year: 2002

  15. The Use of the Silver Solid Amalgam Electrode for Voltammetric Determination of 9-Nitroanthracene

    Czech Academy of Sciences Publication Activity Database

    Navrátil, Tomáš; Nováková, Kateřina; Barek, J.; Vyskočil, V.; Chýlková, J.

    2016-01-01

    Roč. 49, č. 1 (2016), s. 37-48 ISSN 0003-2719 R&D Projects: GA ČR(CZ) GAP208/12/1645 Institutional support: RVO:61388955 Keywords : 9-Nitroanthracene * Silver solid amalgam electrode * Voltammetry Subject RIV: CG - Electrochemistry Impact factor: 1.150, year: 2016

  16. Amalgam shear bond strength to dentin using single-bottle primer/adhesive systems.

    Science.gov (United States)

    Cobb, D S; Denehy, G E; Vargas, M A

    1999-10-01

    To evaluate the in vitro shear bond strengths (SBS) of a spherical amalgam alloy (Tytin) to dentin using several single-bottle primer/adhesive systems both alone: Single Bond (SB), OptiBond Solo (Sol), Prime & Bond 2.1 (PB), One-Step (OS) and in combination with the manufacturer's supplemental amalgam bonding agent: Single Bond w/3M RelyX ARC (SBX) and Prime & Bond 2.1 w/Amalgam Bonding Accessory Kit (PBA). Two, three-component adhesive systems, Scotchbond Multi-Purpose (SBMP) and Scotchbond Multi-Purpose Plus w/light curing (S + V) and w/o light curing (S+) were used for comparison. One hundred eight extracted human third molars were mounted lengthwise in phenolic rings with acrylic resin. The proximal surfaces were ground to expose a flat dentin surface, then polished to 600 grit silicon carbide paper. The teeth were randomly assigned to 9 groups (n = 12), and dentin surfaces in each group were treated with an adhesive system according to the manufacturer's instructions, except for S + V specimens, where the adhesive was light cured for 10 s before placing the amalgam. Specimens were then secured in a split Teflon mold, having a 3 mm diameter opening and amalgam was triturated and condensed onto the treated dentin surfaces. Twenty minutes after condensation, the split mold was separated. Specimens were placed in distilled water for 24 hrs, then thermocycled (300 cycles, between 5 degrees C and 55 degrees C, with 12 s dwell time). All specimens were stored in 37 degrees C distilled water for 7 days, prior to shear strength testing using a Zwick Universal Testing Machine at a cross-head speed of 0.5 mm/min. The highest to the lowest mean dentin shear bond strength values (MPa) for the adhesive systems tested were: S + V (10.3 +/- 2.3), SBX (10.2 +/- 3.5), PBA, (6.4 +/- 3.6), SOL (5.8 +/- 2.5), SBMP (5.7 +/- 1.8), S+ (4.8 +/- 2.3), PB (2.7 +/- 2.6), SB (2.7 +/- 1.1) and OS (2.5 +/- 1.8). One-way ANOVA and Duncan's Multiple Range Test indicated significant

  17. A REFLECTION ON THE WAVE OF AMALGAMATIONS IN THE ROMANIAN HEALTH SECTOR

    Directory of Open Access Journals (Sweden)

    Ina MITU

    2014-12-01

    Full Text Available In the context of New Public Management (NPM and good governance, in the last decade the Romanian public health system has undergone a reform process. One of its consequences is the wave of public hospitals amalgamations that have occurred especially since the adoption of the new health law. Thus, in 2011 the Ministry of Health has made public a list of proposed amalgamations of hospitals (around 25% from total hospitals with beds that existed in that period. The aim of this research is to examine the wave of hospital mergers that occurred in Romania between 2011 and 2012. In particular, the study focuses on the drivers, social impact, typology and purpose of the analysed amalgamations. The study uses primary resources documents and it is based on a content analysis of 25 Government Decisions and Substantiation Notes from 2011 to 2012. An important generalization of the paper is that all the amalgamations from the analysed period are involuntary and are selected on territorial criteria and depending on the distance, the specific health services for the purpose of efficient use of human and material resources in order to enhance public health services. Additionally, the expected social impact of these events is materialized mainly in improving the quality of medical services provided to the population and providing unconditional access to medical services for policyholders. The expected changes include: reduction of staff costs; efficient use of public services; classifying the amalgamated hospitals in a higher category; reduction of management positions; optimizing medical activity in terms of economic efficiency; and achieving a management capable of the best use of existing financial resources.

  18. Effect of radiofrequency radiation from Wi-Fi devices on mercury release from amalgam restorations.

    Science.gov (United States)

    Paknahad, Maryam; Mortazavi, S M J; Shahidi, Shoaleh; Mortazavi, Ghazal; Haghani, Masoud

    2016-01-01

    Dental amalgam is composed of approximately 50% elemental mercury. Despite concerns over the toxicity of mercury, amalgam is still the most widely used restorative material. Wi-Fi is a rapidly using local area wireless computer networking technology. To the best of our knowledge, this is the first study that evaluates the effect of exposure to Wi-Fi signals on mercury release from amalgam restorations. Standard class V cavities were prepared on the buccal surfaces of 20 non-carious extracted human premolars. The teeth were randomly divided into 2 groups (n = 10). The control group was stored in non-environment. The specimens in the experimental groups were exposed to a radiofrequency radiation emitted from standard Wi Fi devices at 2.4 GHz for 20 min. The distance between the Wi-Fi router and samples was 30 cm and the router was exchanging data with a laptop computer that was placed 20 m away from the router. The concentration of mercury in the artificial saliva in the groups was evaluated by using a cold-vapor atomic absorption Mercury Analyzer System. The independent t test was used to evaluate any significant differences in mercury release between the two groups. The mean (±SD) concentration of mercury in the artificial saliva of the Wi-Fi exposed teeth samples was 0.056 ± .025 mg/L, while it was only 0.026 ± .008 mg/L in the non-exposed control samples. This difference was statistically significant (P =0.009). Exposure of patients with amalgam restorations to radiofrequency radiation emitted from conventional Wi-Fi devices can increase mercury release from amalgam restorations.

  19. [A study of different polishing techniques for amalgams and glass-cermet cement by scanning electron microscope (SEM)].

    Science.gov (United States)

    Kakaboura, A; Vougiouklakis, G; Argiri, G

    1989-01-01

    Finishing and polishing an amalgam restoration, is considered as an important and necessary step of the restorative procedure. Various polishing techniques have been recommended to success a smooth amalgam surface. The aim of this study was to investigate the influence of three different polishing treatments on the marginal integrity and surface smoothness of restorations made of three commercially available amalgams and a glass-cermet cement. The materials used were the amalgams, Amalcap (Vivadent), Dispersalloy (Johnson and Johnson), Duralloy (Degussa) and the glass-cermet Katac-Silver (ESPE). The occlusal surfaces of the restorations were polished by the methods: I) round bur, No4-rubber cup-zinc oxide paste in a small brush, II) round bur No 4-bur-brown, green and super green (Shofu) polishing cups and points successively and III) amalgam polishing bur of 12-blades-smooth amalgam polishing bur. Photographs from unpolished and polished surfaces of the restorations, were taken with scanning electron microscope, to evaluate the polishing techniques. An improvement of marginal integrity and surface smoothness of all amalgam restorations was observed after the specimens had been polished with the three techniques. Method II, included Shofu polishers, proved the best results in comparison to the methods I and III. Polishing of glass-cermet cement was impossible with the examined techniques.

  20. Tension-filled Governance?

    DEFF Research Database (Denmark)

    Celik, Tim Holst

    on the statesituated tension-filled functional relationship between legitimation and accumulation, the study both historically and theoretically reworks this approach and reapplies it for the post-1970s/1990s governance period. It asks whether and to what extent governance has served as a distinctive post- 1970s/1990s...

  1. filled neutron detectors

    Indian Academy of Sciences (India)

    Boron trifluoride (BF3) proportional counters are used as detectors for thermal neutrons. They are characterized by high neutron sensitivity and good gamma discriminating properties. Most practical BF3 counters are filled with pure boron trifluoride gas enriched up to 96% 10B. But BF3 is not an ideal proportional counter ...

  2. Gas filled detectors

    International Nuclear Information System (INIS)

    Stephan, C.

    1993-01-01

    The main types of gas filled nuclear detectors: ionization chambers, proportional counters, parallel-plate avalanche counters (PPAC) and microstrip detectors are described. New devices are shown. A description of the processes involved in such detectors is also given. (K.A.) 123 refs.; 25 figs.; 3 tabs

  3. Comparison of chlorine and chloramine in the release of mercury from dental amalgam.

    Science.gov (United States)

    Stone, Mark E; Scott, John W; Schultz, Stephen T; Berry, Denise L; Wilcoxon, Monte; Piwoni, Marv; Panno, Brent; Bordson, Gary

    2009-01-01

    The purpose of this project was to compare the ability of chlorine (HOCl/OCl(-)) and monochloramine (NH(2)Cl) to mobilize mercury from dental amalgam. Two types of amalgam were used in this investigation: laboratory-prepared amalgam and samples obtained from dental-unit wastewater. For disinfectant exposure simulations, 0.5 g of either the laboratory-generated or clinically obtained amalgam waste was added to 250 mL amber bottles. The amalgam samples were agitated by end-over-end rotation at 30 rpm in the presence of 1 mg/L chlorine, 10 mg/L chlorine, 1 mg/L monochloramine, 10 mg/L monochloramine, or deionized water for intervals of 0 h, 2 h, 4 h, 8 h, and 24 h for the clinically obtained amalgam waste samples and 4 h and 24 h for the laboratory-prepared samples. Chlorine and monochloramine concentrations were measured with a spectrophotometer. Samples were filtered through a 0.45 microm membrane filter and analyzed for mercury with USEPA standard method 245.7. When the two sample types were combined, the mean mercury level in the 1 mg/L chlorine group was 0.020 mg/L (n=25, SD=0.008). The 10 mg/L chlorine group had a mean mercury concentration of 0.59 mg/L (n=25, SD=1.06). The 1 mg/L chloramine group had a mean mercury level of 0.023 mg/L (n=25, SD=0.010). The 10 mg/L chloramine group had a mean mercury level of 0.024 mg/L (n=25, SD=0.011). Independent samples t-tests showed that there was a significant difference between the natural log mercury measurements of 10 mg/L chlorine compared to those of 1 mg/L and 10 mg/L chloramine. Changing from chlorine to chloramine disinfection at water treatment plants would not be expected to produce substantial increases in dissolved mercury levels in dental-unit wastewater.

  4. Systolic ventricular filling.

    Science.gov (United States)

    Torrent-Guasp, Francisco; Kocica, Mladen J; Corno, Antonio; Komeda, Masashi; Cox, James; Flotats, A; Ballester-Rodes, Manel; Carreras-Costa, Francesc

    2004-03-01

    The evidence of the ventricular myocardial band (VMB) has revealed unavoidable coherence and mutual coupling of form and function in the ventricular myocardium, making it possible to understand the principles governing electrical, mechanical and energetical events within the human heart. From the earliest Erasistratus' observations, principal mechanisms responsible for the ventricular filling have still remained obscured. Contemporary experimental and clinical investigations unequivocally support the attitude that only powerful suction force, developed by the normal ventricles, would be able to produce an efficient filling of the ventricular cavities. The true origin and the precise time frame for generating such force are still controversial. Elastic recoil and muscular contraction were the most commonly mentioned, but yet, still not clearly explained mechanisms involved in the ventricular suction. Classical concepts about timing of successive mechanical events during the cardiac cycle, also do not offer understandable insight into the mechanism of the ventricular filling. The net result is the current state of insufficient knowledge of systolic and particularly diastolic function of normal and diseased heart. Here we summarize experimental evidence and theoretical backgrounds, which could be useful in understanding the phenomenon of the ventricular filling. Anatomy of the VMB, and recent proofs for its segmental electrical and mechanical activation, undoubtedly indicates that ventricular filling is the consequence of an active muscular contraction. Contraction of the ascendent segment of the VMB, with simultaneous shortening and rectifying of its fibers, produces the paradoxical increase of the ventricular volume and lengthening of its long axis. Specific spatial arrangement of the ascendent segment fibers, their interaction with adjacent descendent segment fibers, elastic elements and intra-cavitary blood volume (hemoskeleton), explain the physical principles

  5. The mercury-richest europium amalgam Eu{sub 10}Hg{sub 55}

    Energy Technology Data Exchange (ETDEWEB)

    Tambornino, Frank; Hoch, Constantin [Department of Chemistry, Ludwig-Maximilians-Universitaet Muenchen (Germany)

    2015-03-15

    The mercury-richest europium amalgam Eu{sub 10}Hg{sub 55} was synthesized by isothermal electrocrystallization from a solution of EuI{sub 3}.8DMF in DMF on a reactive mercury cathode. The crystal structure shows remarkable complexity and polar metal-metal bonding. Closely related to the structures of mercury-rich amalgams A{sub 11-x}Hg{sub 55+x} (A = Na, Ca, Sr), it shows underoccupied Hg positions along [00z]. Eu{sub 10}Hg{sub 55} can be described as hettotype structure of the Gd{sub 14}Ag{sub 51} structure type. (Copyright copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  6. Physico-Chemical Study of the Separation of Calcium Isotopes by Chemical Exchange Between Amalgam and Salt Solutions

    International Nuclear Information System (INIS)

    Duie, P.; Dirian, G.

    1962-01-01

    In a preliminary study of the isotopic exchange between Ca amalgam and aqueous or organic solutions of Ca salts, the main parameters governing the feasibility of a separation process based on these systems such as separation factor, exchange kinetics, rate of decomposition of the amalgam were investigated. The separation factor between 40 Ca and 46 Ca was found to be of the order of 1.02. The rate of the exchange reaction is rather low for aqueous solutions, extremely low for organic solutions. The amalgam seems not to be attacked by dimethyl-formamide solutions; but it is rapidly decomposed by aqueous solutions of Ca halides. This decomposition is slow in the case of aqueous solutions of calcium formate and still slower for Ca(OH) 2 ; however, except in particular conditions, the observed rate is often much higher, owing to interfering reactions between amalgam and water vapor contained in H 2 bubbles. (authors) [fr

  7. Sensitive voltammetric method for determination of herbicide triasulfuron using silver solid amalgam electrode

    Czech Academy of Sciences Publication Activity Database

    Bandžuchová, L.; Šelešovská, R.; Navrátil, Tomáš; Chýlková, J.

    2013-01-01

    Roč. 113, DEC 2013 (2013), s. 1-8 ISSN 0013-4686 R&D Projects: GA ČR(CZ) GAP208/12/1645 Grant - others:GA MŠk(CZ) CZ.1.07/2.3.00/30.0021 Institutional support: RVO:61388955 Keywords : Triasulfuron * Hanging mercury drop electrode * Mercury meniscus modified silver solid amalgam electrode Subject RIV: CG - Electrochemistry Impact factor: 4.086, year: 2013

  8. Liquid-Mercury Free Silver Solid Amalgam Electrode - Tool for Electroanalysis of Organic Compounds

    Czech Academy of Sciences Publication Activity Database

    Šelešovská-Fadrná, R.; Navrátil, Tomáš; Vlček, Milan

    2007-01-01

    Roč. 52, č. 6 (2007), s. 911-929 ISSN 0009-2223 R&D Projects: GA ČR GA203/07/1195; GA MŠk(CZ) LC06035 Institutional research plan: CEZ:AV0Z40400503; CEZ:AV0Z40500505 Keywords : ascorbic acid * solid silver amalgam electrodes * cysteine * voltammetry Subject RIV: CG - Electrochemistry Impact factor: 0.529, year: 2007

  9. Voltammetric Determination of 4-Nitrophenol Using a Novel Type of Silver Amalgam Paste Electrode

    Czech Academy of Sciences Publication Activity Database

    Niaz, A.; Fischer, J.; Barek, J.; Josypčuk, Bohdan; Sirajuddin, C.; Bhanger, M. I.

    2009-01-01

    Roč. 21, č. 16 (2009), s. 1786-1791 ISSN 1040-0397 R&D Projects: GA MŠk(CZ) LC06035; GA ČR GA203/07/1195 Institutional research plan: CEZ:AV0Z40400503 Keywords : voltammetry * drinking water * silver amalgam paste electrode * 4-nitrophenol Subject RIV: CG - Electrochemistry Impact factor: 2.630, year: 2009

  10. Fracture Resistance of Pulpotomized Primary Molar Restored with Extensive Class II Amalgam Restorations

    Directory of Open Access Journals (Sweden)

    F. Mazhari

    2008-06-01

    Full Text Available Objective: The aim of the present study was to evaluate fracture resistance of pulpoto-mized primary molar teeth restored with extensive multisurface amalgam restorations.Materials and Methods: Eighty extracted carious human primary molar teeth were se-lected forpresent study. Teeth were divided in to eight groups of ten. Mesio- or disto-occlusal and Mesio-occluso-distal cavities with different cavity wall thickness (1.5 or 2.5mm were prepared in both first and second primary molar teeth. After restoring teeth with amalgam, all specimens were stored in distilled water at 37°C for 7 days. Then samples were thermocycled for 1000 cycles from 5°C to 55°C. The specimens then were subjected to a compressive load in a universal testing machine at a crosshead speed of 0.5 mm min-1. ANOVA and t-test were used for statistical analysis.Results: Mean fracture resistance of first and second molar teeth were 975.5 N (SD=368.8 and 1049.2 N (SD=540.1 respectively. In the first molar group, fracture resis-tance of two-surface cavities was significantly more than three-surface cavities (P<0.001, however this difference was not statistically significant in the second molar group. In both first and second molar group, fracture resistance incavities with 2.5 mm wall thickness, was significantly more than the group with 1.5 mm wall thickness.Conclusion: The mean fracture resistance in pulpotomized primary molar restored with amalgam restorations was higher than reported maximum bite force in primary teeth even in extensive multi-surface restorations. Therefore, the teeth with large proximal carious lesions in schoolchildren could be restored with amalgam.

  11. Shear bond strength of amalgam to dentin using different dentin adhesive systems

    Directory of Open Access Journals (Sweden)

    Farimah Sardari

    2012-01-01

    Full Text Available Background and Aims: The aim of this in vitro study was to assess the shear bond strength of amalgam to dentin using four dentin adhesive systems.Materials and Methods: One hundred human molars were selected. After enamel removal, a dentin cylinder with 3 mm thickness was prepared. Eighty specimens were resorted with amalgam and four dentin adhesive systems as follows (n=20: group 1, Scotch Bond Multi-Purpose; group 2, One Coat Bond; group 3, PQ1; and group 4, Panavia-F. In group 5, 20 specimens were resorted with amalgam and varnish as control group. The specimens were incubated at 37°C for 24 h. The shear bond strengths were then measured by using push out method. The data were analyzed by one-way ANOVA and post hoc Duncan's tests.Results: Mean values for bond strengths of test groups were as follows: group 1=21.03±8.9, group 2=23.47±9, group 3=13.16±8.8, group 4=20.07±8.9 and group 5=14.15±8.7 MPa±SD. One-way ANOVA showed the statistically significant difference between the bond strengths of five groups (P=0.001. Post hoc Duncan's test showed significant difference between groups 1and 3 (P=0.008, groups 1 and 5 (P=0.019, groups 2 and 5 (P=0.0008, groups 4 and 5 (P=0.042, and groups 3 and 4 (P=0.018.Conclusion: Results of this study showed that the bond strength of amalgam to dentin using One Coat Bond as dentin adhesive system was higher than that observed in other dentin adhesive systems.

  12. Effect of amalgam cuspal coverage on the fracture resistance of endodontically treated teeth

    Directory of Open Access Journals (Sweden)

    Mahshid Mohammdi Basir

    2013-05-01

    Full Text Available   Background and Aims: Endodontically treated teeth are prone to fracture because they loose a big amount of their structure. The treatment plan of those teeth is completed when they are rehabilitated with a strong and functional restoration. The purpose of this study was to evaluate the fracture resistance of endodontically treated teeth restored with amalgam cuspal coverage in comparison with other restorative techniques.   Materials and Methods: 40 human healthy maxillary premolars were divided into 4 groups: group1 (S: sound teeth, group 2(Co: endodontically treated teeth with MOD cavity restored with bonding and composite, group 3(Am-B: endodontically treated teeth with MOD cavity restored with bonding and amalgam and group 4 (Am-CC: endodontically treated teeth with MOD cavity restored with amalgam cuspal coverage. Then the restorations were stored in water and room temperature for 100 days at then thermocycled for 500 cycles between water baths at (5.5 ± 1 and (55 ± 1 0 C. The fracture resistance was evaluated by universal testing machine (Instron, 1195 UK with the compressive force of about 2000 N in 0.5 mm/min. The fracture modes were evaluated in four groups by a stereomicroscope. Statistical analysis (Scheffe test was done for all groups (P0.05. The lowest fracture resistance was found in group 2 (Co (384 ± 137.4 N that had no significant difference with group 3 (Am-B (P>0.05. The fracture resistance in group 4 was significantly higher than group 2 (Co and 3 (Am-B. The fracture mode in group 1 was cohesive within tooth and in group 2 (Co and 3 (Am-B was mixed cohesive and adhesive, and in group 4 was cohesive within in restorative material.   Conclusion: The highest fracture resistance was found in teeth that received amalgam cuspal coverage.

  13. Influence of different bonding agents on marginal sealing quality of amalgam restorations

    Directory of Open Access Journals (Sweden)

    Melih Irena

    2011-01-01

    Full Text Available Introduction. Although advanced adhesive systems are in use, marginal microleakage is one of the greatest problems of contemporary restorative dentistry. Objective. The aim of this in vitro study was to evaluate the influence of different bonding agents on the marginal sealing quality of class II amalgam restorations. Methods. Forty freshly extracted human premolar and molar teeth were divided into four groups with 10 teeth in each one. Class II preparations were prepared and different adhesives were applied as follows: group I - Amalgam Liner® (Voco; group II - ONE-STEP® PLUS (Bisco; group III - PQ 1 (Ultradent. Group IV was used as a control, without any bonding agent. Amalgam (Cavex Non Gamma 2, Cavex was hand-condensed into each preparation. Specimens were thermocycled 200 times at the following temperatures: 5-7°C, 37°C and 57-59°C, and were then immersed into 1% solution of gentian violet for 72 hours. The teeth were sectioned longitudinally and microleakage was graded in the area of the gingival and occlusal quantity rim using a binocular magnifying glass with 25 times magnification. Results. The highest microleakage was recorded in the Amalgam Liner group; 1526.0 μm at the gingival wall and 694.5 μm at the occlusal cavity wall. The lowest dye penetration was observed in the PQ1 group; 589.5 μm at the gingival wall, and 599.9 μm at the occlusal wall of the restoration. ANOVA test showed that there was a statistically significant difference of dye penetration values at the gingival wall among all examination groups (p<0.01. No statistically significant differences were found comparing microleakage values at the occlusal wall. Conclusion. Results of this study showed that the best marginal sealing was accomplished by using the PQ1 bonding agent.

  14. A biologists' perspective on amalgamating traditional environmental knowledge and resource management

    OpenAIRE

    A.W.L. Hawley; Sherry, E.E.; Johnson, C.J.

    2004-01-01

    Recent transitions in resource management and recognition of the role of First Nations in resource management have heightened the need for conciliation of these two different views of the world and the place of people in it (world view). Efforts to amalgamate these diverse perspectives in resource management are impeded by a legacy of cultural imperialism and difficulties in understanding and accommodating differences in world views, including the place of resource management in society, the ...

  15. Voltammetric Determination of 4-Nitrophenol and 5-Nitrobenzimidazole Using Different Types of Silver Solid Amalgam Electrodes - A Comparative Study

    Czech Academy of Sciences Publication Activity Database

    Deýlová, D.; Josypčuk, Bohdan; Vyskočil, V.; Barek, J.

    2011-01-01

    Roč. 23, č. 7 (2011), s. 1548-1555 ISSN 1040-0397 R&D Projects: GA MŠk(CZ) LC06063; GA AV ČR IAA400400806 Institutional research plan: CEZ:AV0Z40400503 Keywords : voltammetry * polished silver solid amalgam electrode * Mercury meniscus modified silver solid amalgam electrode Subject RIV: CG - Electrochemistry Impact factor: 2.872, year: 2011

  16. TrigDB back-filling method in EEW for the regional earthquake for reducing false location of the deep focus earthquake event by considering neighborhood triggers and forced association.

    Science.gov (United States)

    Park, J. H.; Chi, H. C.; Lim, I. S.; Seong, Y. J.; Pak, J.

    2017-12-01

    During the first phase of EEW(Earthquake Early Warning) service to the public by KMA (Korea Meteorological Administration) from 2015 in Korea, KIGAM(Korea Institute of Geoscience and Mineral Resources) has adopted ElarmS2 of UC Berkeley BSL and modified local magnitude relation, travel time curves and association procedures so called TrigDB back-filling method. The TrigDB back-filling method uses a database of sorted lists of stations based on epicentral distances of the pre-defined events located on the grids for 1,401 × 1,601 = 2,243,001 events around the Korean Peninsula at a grid spacing of 0.05 degrees. When the version of an event is updated, the TrigDB back-filling method is invoked. First, the grid closest to the epicenter of an event is chosen from the database and candidate stations, which are stations corresponding to the chosen grid and also adjacent to the already-associated stations, are selected. Second, the directions from the chosen grid to the associated stations are averaged to represent the direction of wave propagation, which is used as a reference for computing apparent travel times. The apparent travel times for the associated stations are computed using a P wave velocity of 5.5 km/s from the grid to the projected points in the reference direction. The travel times for the triggered candidate stations are also computed and used to obtain the difference between the apparent travel times of the associated stations and the triggered candidates. Finally, if the difference in the apparent travel times is less than that of the arrival times, the method forces the triggered candidate station to be associated with the event and updates the event location. This method is useful to reduce false locations of events which could be generated from the deep (> 500 km) and regional distance earthquakes happening on the subduction pacific plate boundaries. In comparison of the case study between TrigDB back-filling applied system and the others, we could get

  17. Determination of the cathode and anode voltage drops in high power low-pressure amalgam lamps

    International Nuclear Information System (INIS)

    Vasilyak, L. M.; Vasiliev, A. I.; Kostyuchenko, S. V.; Sokolov, D. V.; Startsev, A. Yu.; Kudryavtsev, N. N.

    2011-01-01

    For the first time, cathode and anode drops of powerful low-pressure amalgam lamps were measured. The lamp discharge current is 3.2 A, discharge current frequency is 43 kHz, linear electric power is 2.4 W/cm. The method of determination of a cathode drop is based on the change of a lamp operating voltage at variation of the electrode filament current at constant discharge current. The total (cathode plus anode) drop of voltage was measured by other, independent ways. The maximum cathode fall is 10.8 V; the anode fall corresponding to the maximal cathode fall is 2.4 V. It is shown that in powerful low pressure amalgam lamps the anode fall makes a considerable contribution (in certain cases, the basic one) to heating of electrodes. Therefore, the anode fall cannot be neglected, at design an electrode and ballast of amalgam lamps with operating discharge current frequency of tens of kHz.

  18. Determination of the cathode and anode voltage drops in high power low-pressure amalgam lamps

    Energy Technology Data Exchange (ETDEWEB)

    Vasilyak, L. M., E-mail: vasilyak@ihed.ras.ru [Russian Academy of Sciences, Joint Institute for High Temperatures (Russian Federation); Vasiliev, A. I., E-mail: vasiliev@npo.lit.ru; Kostyuchenko, S. V.; Sokolov, D. V.; Startsev, A. Yu. [Joint Stock Company NPO LIT (Russian Federation); Kudryavtsev, N. N. [Moscow Institute of Physics and Technology (State University) (Russian Federation)

    2011-12-15

    For the first time, cathode and anode drops of powerful low-pressure amalgam lamps were measured. The lamp discharge current is 3.2 A, discharge current frequency is 43 kHz, linear electric power is 2.4 W/cm. The method of determination of a cathode drop is based on the change of a lamp operating voltage at variation of the electrode filament current at constant discharge current. The total (cathode plus anode) drop of voltage was measured by other, independent ways. The maximum cathode fall is 10.8 V; the anode fall corresponding to the maximal cathode fall is 2.4 V. It is shown that in powerful low pressure amalgam lamps the anode fall makes a considerable contribution (in certain cases, the basic one) to heating of electrodes. Therefore, the anode fall cannot be neglected, at design an electrode and ballast of amalgam lamps with operating discharge current frequency of tens of kHz.

  19. Thermal diffusion through amalgam and cement base: comparison of in vitro and in vivo measurements.

    Science.gov (United States)

    Tibbetts, V R; Schnell, R J; Swartz, M L; Phillips, R W

    1976-01-01

    Thermal diffusion was measured in vitro and in vivo through amalgam and amalgam underlaid with bases of zinc phosphate, zinc oxide-eugenol, and calcium hydroxide cements. Although the magnitudes differed, there generally was good agreement between in vitro and in vivo data with respect to the relative rates of thermal diffusivity through amalgam restorations underlaid with bases of each of the three materials. In all tests, both in vitro and in vivo, the zinc oxide-eugenol base proved to be the best thermal insulator. Calcium hydroxide was the next best thermal barrier and was followed by zinc phosphate cement. In vitro tests indicated dentin to be a better thermal insulator than zinc phosphate cement but inferior to the zinc oxide-eugenol and calcium hydroxide base materials used here. Although a method has been presented here for the in vivo assessment of the efficacy of thermal insulating bases and a number of in vivo experiments were conducted, much research remains to be done in this area. Additional investigation is needed to better define the parameters of thermal change beneath various types of restoratives and also to establish more exactly the role of base thickness in providing thermal protection beneath clinical metallic restorations.

  20. 33 CFR 183.564 - Fuel tank fill system.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Fuel tank fill system. 183.564...) BOATING SAFETY BOATS AND ASSOCIATED EQUIPMENT Fuel Systems Manufacturer Requirements § 183.564 Fuel tank fill system. (a) Each fuel fill opening must be located so that a gasoline overflow of up to five...

  1. In Vitro Description of Macroscopic Changes of Dental Amalgam Discs Subject to High Temperatures to Forensic Purposes.

    Science.gov (United States)

    Arcos, Carlos; Díaz, Juan-David; Canencio, Kenny; Rodríguez, Diana; Viveros, Carlos; Vega, Jonathan; Lores, Juliana; Sinisterra, Gustavo; Sepúlveda, Wilmer; Moreno, Freddy

    2015-07-01

    To describe the behavior of 45 discs of dental amalgam of known dimension prepared from three commercially available brands of dental amalgam (Contour® Kerr®-USA, Admix® SDI®-Australia and Nu Alloy® Newstethic®-Colombia) when subjected to the action of high temperatures (200 °C, 400 °C, 600 °C, 800 °C, 1000 °C). It was hoped to establish parameters that could be used for human dental identification in cases of charred, burned or incinerated human remains. A pseudo-experimental descriptive in-vitro study was designed to describe the macroscopic physical changes to the surface of 45 discs of pre-prepared amalgam of three commercially available brands exposed to a range of high temperatures. Characteristic and repetitive physical changes were a noticeable feature of the discs of amalgam of each brand of amalgam subjected to the different temperature ranges. These physical changes included changes in dimensional stability, changes in texture, changes in colour, changes in the appearance of fissures and cracks and changes in the fracture and fragmentation of the sample. The characteristics of dental amalgam may be of assistance in cases of human identification where charred, burned or incinerated human remains are a feature and where fingerprints or other soft tissue features are unavailable.

  2. Composite Replacement of Amalgam Restoration Versus Freshly Cut Dentin: An In Vitro Microleakage Comparison.

    Science.gov (United States)

    Redwan, H; Bardwell, D N; Ali, A; Finkelman, M; Khayat, S; Weber, H-P

    2016-01-01

    The aim of this study was to evaluate the microleakage of the composite restorations when bonded to tooth structure previously restored with amalgam material compared with that of freshly cut dentin. Thirty intact, extracted intact human molars were mounted in autopolymerizing acrylic resin. Class II box preparations were prepared on the occluso-proximal surfaces of each tooth (4-mm bucco-lingual width and 2-mm mesio-distal depth) with the gingival cavosurface margin 1 mm above the CEJ. Each cavity was then restored using high copper amalgam restoration (Disperalloy, Dentsply) and then thermocycled for 10,000 thermal cycles. Twenty-five of the amalgam restorations were then carefully removed and replaced with Filtek Supreme Ultra Universal (3M ESPE); the remaining five were used for scanning electron microscopy and energy dispersive x-ray spectroscopy analysis. A preparation of the same dimensions was performed on the opposite surface of the tooth and restored with composite resin and thermocycled for 5000 thermal cycles. Twenty samples were randomly selected for dye penetration testing using silver nitrate staining to detect the microleakage. The specimens were analyzed with a stereomicroscope at a magnification of 20×. All of the measurements were done in micrometers; two readings were taken for each cavity at the occlusal and proximal margins. Two measurements were taken using a 0-3 scale and the percentage measurements. Corrosion products were not detected in either group (fresh cut dentin and teeth previously restored with amalgam). No statistically significant difference was found between the microleakage of the two groups using a 0-3 scale at the occlusal margins (McNemar test, p=0.727) or proximal margins (Wilcoxon signed-rank test, p=0.174). No significance difference was found between the two groups using the percentage measurements and a Wilcoxon signed-rank test at either the occlusal (p=0.675) or proximal (p=0.513) margins. However, marginal

  3. Dye filled security seal

    International Nuclear Information System (INIS)

    Wilson, D.C.

    1982-01-01

    A security seal for providing an indication of unauthorized access to a sealed object includes an elongate member to be entwined in the object such that access is denied unless the member is removed. The elongate member has a hollow, pressurizable chamber extending throughout its length that is filled with a permanent dye under greater than atmospheric pressure. Attempts to cut the member and weld it together are revealed when dye flows through a rupture in the chamber wall and stains the outside surface of the member

  4. Benign gastric filling defect

    International Nuclear Information System (INIS)

    Oh, K. K.; Lee, Y. H.; Cho, O. K.; Park, C. Y.

    1979-01-01

    The gastric lesion is a common source of complaints to Orientals, however, evaluation of gastric symptoms and laboratory examination offer little specific aid in the diagnosis of gastric diseases. Thus roentgenography of gastrointestinal tract is one of the most reliable method for detail diagnosis. On double contract study of stomach, gastric filling defect is mostly caused by malignant gastric cancer, however, other benign lesions can cause similar pictures which can be successfully treated by surgery. 66 cases of benign causes of gastric filling defect were analyzed at this point of view, which was verified pathologically by endoscope or surgery during recent 7 years in Yensei University College of Medicine, Severance Hospital. The characteristic radiological picture of each disease was discussed for precise radiologic diagnosis. 1. Of total 66 cases, there were 52 cases of benign gastric tumor 10 cases of gastric varices, 5 cases of gastric bezoar, 5 cases of corrosive gastritis, 3 cases of granulomatous disease and one case of gastric hematoma. 2. The most frequent causes of benign tumors were adenomatous polyp (35/42) and the next was leiomyoma (4/42). Others were one of case of carcinoid, neurofibroma and cyst. 3. Characteristic of benign adenomatous polyp were relatively small in size, smooth surface and were observed that large size, benign polyp was frequently type IV lesion with a stalk. 4. Submucosal tumors such as leiomyoma needed differential diagnosis with polypoid malignant cancer. However, the characteristic points of differentiation was well circumscribed smooth margined filling defect without definite mucosal destruction on surface. 5. Gastric varices showed multiple lobulated filling defected especially on gastric fundus that changed its size and shape by respiration and posture of patients. Same varices lesions on esophagus and history of liver disease were helpful for easier diagnosis. 6. Gastric bezoar showed well defined movable mass

  5. Benign gastric filling defect

    Energy Technology Data Exchange (ETDEWEB)

    Oh, K. K.; Lee, Y. H.; Cho, O. K.; Park, C. Y. [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    1979-06-15

    The gastric lesion is a common source of complaints to Orientals, however, evaluation of gastric symptoms and laboratory examination offer little specific aid in the diagnosis of gastric diseases. Thus roentgenography of gastrointestinal tract is one of the most reliable method for detail diagnosis. On double contract study of stomach, gastric filling defect is mostly caused by malignant gastric cancer, however, other benign lesions can cause similar pictures which can be successfully treated by surgery. 66 cases of benign causes of gastric filling defect were analyzed at this point of view, which was verified pathologically by endoscope or surgery during recent 7 years in Yensei University College of Medicine, Severance Hospital. The characteristic radiological picture of each disease was discussed for precise radiologic diagnosis. 1. Of total 66 cases, there were 52 cases of benign gastric tumor 10 cases of gastric varices, 5 cases of gastric bezoar, 5 cases of corrosive gastritis, 3 cases of granulomatous disease and one case of gastric hematoma. 2. The most frequent causes of benign tumors were adenomatous polyp (35/42) and the next was leiomyoma (4/42). Others were one of case of carcinoid, neurofibroma and cyst. 3. Characteristic of benign adenomatous polyp were relatively small in size, smooth surface and were observed that large size, benign polyp was frequently type IV lesion with a stalk. 4. Submucosal tumors such as leiomyoma needed differential diagnosis with polypoid malignant cancer. However, the characteristic points of differentiation was well circumscribed smooth margined filling defect without definite mucosal destruction on surface. 5. Gastric varices showed multiple lobulated filling defected especially on gastric fundus that changed its size and shape by respiration and posture of patients. Same varices lesions on esophagus and history of liver disease were helpful for easier diagnosis. 6. Gastric bezoar showed well defined movable mass

  6. Benign gastric filling defect

    Energy Technology Data Exchange (ETDEWEB)

    Oh, K K; Lee, Y H; Cho, O K; Park, C Y [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    1979-06-15

    The gastric lesion is a common source of complaints to Orientals, however, evaluation of gastric symptoms and laboratory examination offer little specific aid in the diagnosis of gastric diseases. Thus roentgenography of gastrointestinal tract is one of the most reliable method for detail diagnosis. On double contract study of stomach, gastric filling defect is mostly caused by malignant gastric cancer, however, other benign lesions can cause similar pictures which can be successfully treated by surgery. 66 cases of benign causes of gastric filling defect were analyzed at this point of view, which was verified pathologically by endoscope or surgery during recent 7 years in Yensei University College of Medicine, Severance Hospital. The characteristic radiological picture of each disease was discussed for precise radiologic diagnosis. 1. Of total 66 cases, there were 52 cases of benign gastric tumor 10 cases of gastric varices, 5 cases of gastric bezoar, 5 cases of corrosive gastritis, 3 cases of granulomatous disease and one case of gastric hematoma. 2. The most frequent causes of benign tumors were adenomatous polyp (35/42) and the next was leiomyoma (4/42). Others were one of case of carcinoid, neurofibroma and cyst. 3. Characteristic of benign adenomatous polyp were relatively small in size, smooth surface and were observed that large size, benign polyp was frequently type IV lesion with a stalk. 4. Submucosal tumors such as leiomyoma needed differential diagnosis with polypoid malignant cancer. However, the characteristic points of differentiation was well circumscribed smooth margined filling defect without definite mucosal destruction on surface. 5. Gastric varices showed multiple lobulated filling defected especially on gastric fundus that changed its size and shape by respiration and posture of patients. Same varices lesions on esophagus and history of liver disease were helpful for easier diagnosis. 6. Gastric bezoar showed well defined movable mass

  7. Preparing for faster filling

    CERN Multimedia

    CERN Bulletin

    2010-01-01

    Following the programmed technical stop last week, operators focussed on preparing the machine for faster filling, which includes multibunch injection and a faster pre-cycle phase.   The LHC1 screen shot during the first multibunch injection operation. The LHC operational schedule incorporates a technical stop for preventive maintenance roughly every six weeks of stable operation, during which several interventions on the various machines are carried out. Last week these included the replacement of a faulty magnet in the SPS pre-accelerator, which required the subsequent re-setting of the system of particle extraction and transfer to the LHC. At the end of last week, all the machines were handed back for operation and work could start on accommodating all the changes made into the complex systems in order for normal operation to be resumed. These ‘recovery’ operations continued through the weekend and into this week. At the beginning of this week, operators succeeded in pro...

  8. Bulk-Fill Resin Composites

    DEFF Research Database (Denmark)

    Benetti, Ana Raquel; Havndrup-Pedersen, Cæcilie; Honoré, Daniel

    2015-01-01

    the restorative procedure. The aim of this study, therefore, was to compare the depth of cure, polymerization contraction, and gap formation in bulk-fill resin composites with those of a conventional resin composite. To achieve this, the depth of cure was assessed in accordance with the International Organization...... for Standardization 4049 standard, and the polymerization contraction was determined using the bonded-disc method. The gap formation was measured at the dentin margin of Class II cavities. Five bulk-fill resin composites were investigated: two high-viscosity (Tetric EvoCeram Bulk Fill, SonicFill) and three low......-viscosity (x-tra base, Venus Bulk Fill, SDR) materials. Compared with the conventional resin composite, the high-viscosity bulk-fill materials exhibited only a small increase (but significant for Tetric EvoCeram Bulk Fill) in depth of cure and polymerization contraction, whereas the low-viscosity bulk...

  9. Residual mercury content and leaching of mercury and silver from used amalgam capsules.

    Science.gov (United States)

    Stone, M E; Pederson, E D; Cohen, M E; Ragain, J C; Karaway, R S; Auxer, R A; Saluta, A R

    2002-06-01

    The objective of this investigation was to carry out residual mercury (Hg) determinations and toxicity characteristic leaching procedure (TCLP) analysis of used amalgam capsules. For residual Hg analysis, 25 capsules (20 capsules for one brand) from each of 10 different brands of amalgam were analyzed. Total residual Hg levels per capsule were determined using United States Environmental Protection Agency (USEPA) Method 7471. For TCLP analysis, 25 amalgam capsules for each of 10 brands were extracted using a modification of USEPA Method 1311. Hg analysis of the TCLP extracts was done with USEPA Method 7470A. Analysis of silver (Ag) concentrations in the TCLP extract was done with USEPA Method 6010B. Analysis of the residual Hg data resulted in the segregation of brands into three groups: Dispersalloy capsules, Group A, retained the most Hg (1.225 mg/capsule). These capsules were the only ones to include a pestle. Group B capsules, Valliant PhD, Optaloy II, Megalloy and Valliant Snap Set, retained the next highest amount of Hg (0.534-0.770 mg/capsule), and were characterized by a groove in the inside of the capsule. Group C, Tytin regular set double-spill, Tytin FC, Contour, Sybraloy regular set, and Tytin regular set single-spill retained the least amount of Hg (0.125-0.266 mg/capsule). TCLP analysis of the triturated capsules showed Sybraloy and Contour leached Hg at greater than the 0.2 mg/l Resource Conservation and Recovery Act (RCRA) limit. This study demonstrated that residual mercury may be related to capsule design features and that TCLP extracts from these capsules could, in some brands, exceed RCRA Hg limits, making their disposal problematic. At current RCRA limits, the leaching of Ag is not a problem.

  10. Preparation and Properties of Mercury Film Electrodes on Solid Amalgam Surface

    Czech Academy of Sciences Publication Activity Database

    Josypčuk, Bohdan; Fojta, Miroslav; Barek, J.

    2010-01-01

    Roč. 22, 17-18 (2010), s. 1967-1973 ISSN 1040-0397. [International Conference on Modern Electroanalytical Methods. Prague, 09.12.2009-14.12.2009] R&D Projects: GA ČR GA203/07/1195; GA AV ČR IAA400400806; GA MŠk(CZ) LC06035 Institutional research plan: CEZ:AV0Z40400503; CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : voltammetry * solid and paste amalgam * Mercury film electrode Subject RIV: CG - Electrochemistry Impact factor: 2.721, year: 2010

  11. Physico-Chemical Study of the Separation of Calcium Isotopes by Chemical Exchange Between Amalgam and Salt Solutions; Etude physico-chimique de la separation des isotopes du calcium par echange chimique entre amalgame et solution saline

    Energy Technology Data Exchange (ETDEWEB)

    Duie, P; Dirian, G [Commissariat a l' Energie Atomique. Centre d' Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France)

    1962-07-01

    In a preliminary study of the isotopic exchange between Ca amalgam and aqueous or organic solutions of Ca salts, the main parameters governing the feasibility of a separation process based on these systems such as separation factor, exchange kinetics, rate of decomposition of the amalgam were investigated. The separation factor between {sup 40}Ca and {sup 46}Ca was found to be of the order of 1.02. The rate of the exchange reaction is rather low for aqueous solutions, extremely low for organic solutions. The amalgam seems not to be attacked by dimethyl-formamide solutions; but it is rapidly decomposed by aqueous solutions of Ca halides. This decomposition is slow in the case of aqueous solutions of calcium formate and still slower for Ca(OH){sub 2}; however, except in particular conditions, the observed rate is often much higher, owing to interfering reactions between amalgam and water vapor contained in H{sub 2} bubbles. (authors) [French] On a fait une etude preliminaire, pour des systemes amalgame de calcium - solution aqueuse ou organique de sels de calcium, des principaux parametres pouvant intervenir dans l'application d'un procede d'echange a l'enrichissement isotopique du calcium: facteur de separation, cinetique de l'echange, cinetique de la decomposition de l'amalgame. Les facteurs de separation {sup 40}Ca-{sup 46}Ca sont de l'ordre de 1,02. L'echange est assez lent pour les solutions aqueuses, extremement lent pour les solutions organiques. La decomposition de l'amalgame est pratiquement inexistante avec les solutions dans le dimethyl- formamide, appreciable pour les solutions alcooliques, rapide pour les solutions aqueuses d'halogenures; elle est normalement lente pour les solutions aqueuses de formiate et surtout de chaux, mais la decomposition est en general acceleree par une reaction parasite entre l'amalgame et l'eau a l'etat vapeur, reaction que l'on n'evite dans des conditions tres particulieres. (auteurs)

  12. Evaluating the Reasons of Amalgam Restoration Replacement in Esthetic and Restorative Department of Babol Dental School in 2013-14

    Directory of Open Access Journals (Sweden)

    F Abolghasemzade

    2015-08-01

    Results: Within 263 patients, there were 81(30.8% men and 182(69.2% women. Most patients aged 30-40(42.2%, and were reported to suffer from class Ι dental occlusion(92.4%.The mean DMF was 9.7±2.4 . Lower molars were demonstrated as the most frequent teeth group for replacing amalgam restorations as well as causing secondary caries. Furthermore, secondary caries involved the major causes of amalgam restoration replacement. The most prevalent class for amalgam restoration replacement was class II restorations. It should be noted that secondary caries were most prevalent within class II MO / DO(25 cases(44.6%. Conclusion: The study findings revealed that the most common cause of the restoration replacement involved the secondary caries which was most observed in the Class II restorations.

  13. Evaluation of dental amalgam mercury in human body by nuclear techniques

    International Nuclear Information System (INIS)

    Khddour, S.S.

    2000-01-01

    The levels of mercury in blood and hair samples of different groups of population belong to the same geographical areas have been investigated using neutron activation technique. The level of mercury in the blood samples ranged between 1.021 - 81.64 mg/l, while that in the hair samples ranged between 0.17 - 3.95 mg/l. T-test analysis showed higher levels of Hg in blood and hair of group having amalgam restorations comparing to other groups. This study also showed high correlation between the concentration of mercury in the blood of treated and untreated mothers and their newborn babies, where the correlation factors were 0.66 and 0.49 respectively. Correlation between the levels of Hg and Se in the blood was week. It can undoubtedly be concluded that amalgam restorations will contribute in increasing the level of mercury in blood, but although these levels exceed the maximum permissible limit in some samples, there were no any clinical side effects noticed. these levels also remained below the poisoning level.(Author)

  14. Determination of ablation threshold for composite resins and amalgam irradiated with femtosecond laser pulses

    International Nuclear Information System (INIS)

    Freitas, A Z; Samad, R E; Zezell, D M; Vieira Jr, N D; Freschi, L R; Gouw-Soares, S C

    2010-01-01

    The use of laser for caries removal and cavity preparation is already a reality in the dental clinic. The objective of the present study was to consider the viability of ultrashort laser pulses for restorative material selective removal, by determining the ablation threshold fluence for composite resins and amalgam irradiated with femtosecond laser pulses. Lasers pulses centered at 830 nm with 50 fs of duration and 1 kHz of repetition rate, with energies in the range of 300 to 770 μJ were used to irradiate the samples. The samples were irradiated using two different geometrical methods for ablation threshold fluence determinations and the volume ablation was measured by optical coherence tomography. The shape of the ablated surfaces were analyzed by optical microscopy and scanning electron microscopy. The determined ablation threshold fluence is 0.35 J/cm 2 for the composite resins Z-100 and Z-350, and 0.25 J/cm 2 for the amalgam. These values are half of the value for enamel in this temporal regime. Thermal damages were not observed in the samples. Using the OCT technique (optical coherence tomography) was possible to determine the ablated volume and the total mass removed

  15. Potential of Brass to Remove Inorganic Hg(II) from Aqueous Solution through Amalgamation.

    Science.gov (United States)

    Wenke, Axel; Bollen, Anne; Richard, Jan-Helge; Biester, Harald

    2016-06-01

    Brass shavings (CuZn45) were tested for their efficiency to remove Hg(II) from contaminated groundwater through amalgamation. The study was focused on long-term retention efficiency, the understanding of the amalgamation process and kinetics, and influences of filter surface alteration. Column tests were performed with brass filters (thickness 3 to 9 cm) flushed with 1000 μg/L Hg solution for 8 hours under different flow rates (300 to 600 mL/h). Brass filters consistently removed >98% of Hg from solution independent of filter thickness and flow rate. In a long-term experiment (filter thickness 2 cm), Hg retention decreased from 96 to 92% within 2000 hours. Batch and column experiments for studying kinetics of Hg removal indicate ~100% Hg removal from solution within only 2 hours. Solid-phase mercury thermo-desorption analysis revealed that Hg(0) diffusion into the brass surface controls kinetics of mercury retention. Brass surface alteration could be observed, but did not influence Hg retention.

  16. A method for thickness determination of thin films of amalgamable metals by total-reflection X-ray fluorescence

    International Nuclear Information System (INIS)

    Bennun, L.; Greaves, E.D.; Barros, H.; Diaz-Valdes, J.

    2009-01-01

    A method for thickness determination of thin amalgamable metallic films by total-reflection X-ray fluorescence (TXRF) is presented. The peak's intensity in TXRF spectra are directly related to the surface density of the sample, i.e. to its thickness in a homogeneous film. Performing a traditional TXRF analysis on a thin film of an amalgamated metal, and determining the relative peak intensity of a specific metal line, the layer thickness can be precisely obtained. In the case of gold thickness determination, mercury and gold peaks overlap, hence we have developed a general data processing scheme to achieve the most precise results.

  17. Gas-filled hohlraum fabrication

    International Nuclear Information System (INIS)

    Salazar, M.A.; Gobby, P.L.; Foreman, L.R.; Bush, H. Jr.; Gomez, V.M.; Moore, J.E.; Stone, G.F.

    1995-01-01

    Los Alamos National Laboratory (LANL) researchers have fabricated and fielded gas-filled hohlraums at the Lawrence Livermore National Laboratory (LLNL) Nova laser. Fill pressures of 1--5 atmospheres have been typical. We describe the production of the parts, their assembly and fielding. Emphasis is placed on the production of gas-tight polyimide windows and the fielding apparatus and procedure

  18. Mechanics of filled carbon nanotubes

    KAUST Repository

    Monteiro, A.O.; Cachim, P.B.; Da Costa, Pedro M. F. J.

    2014-01-01

    The benefits of filling carbon nanotubes (CNTs) with assorted molecular and crystalline substances have been investigated for the past two decades. Amongst the study of new structural phases, defects, chemical reactions and varied types of host-guest interactions, there is one fundamental characterisation aspect of these systems that continues to be overlooked: the mechanical behaviour of filled CNTs. In contrast to their empty counterparts, the mechanics of filled CNTs is a subject where reports appear far and apart, this despite being key to the application of these materials in technological devices. In the following paragraphs, we review the work that has been carried out up to the present on the mechanics of filled CNTs. The studies discussed range from experimental resonant frequency essays performed within electron microscopes to modelling, via molecular dynamics, of three-point bending of nanotubes filled with gases. (C) 2014 Elsevier B.V. All rights reserved.

  19. Mechanics of filled carbon nanotubes

    KAUST Repository

    Monteiro, A.O.

    2014-04-01

    The benefits of filling carbon nanotubes (CNTs) with assorted molecular and crystalline substances have been investigated for the past two decades. Amongst the study of new structural phases, defects, chemical reactions and varied types of host-guest interactions, there is one fundamental characterisation aspect of these systems that continues to be overlooked: the mechanical behaviour of filled CNTs. In contrast to their empty counterparts, the mechanics of filled CNTs is a subject where reports appear far and apart, this despite being key to the application of these materials in technological devices. In the following paragraphs, we review the work that has been carried out up to the present on the mechanics of filled CNTs. The studies discussed range from experimental resonant frequency essays performed within electron microscopes to modelling, via molecular dynamics, of three-point bending of nanotubes filled with gases. (C) 2014 Elsevier B.V. All rights reserved.

  20. Flow electrochemical biosensors based on enzymatic porous reactor and tubular detector of silver solid amalgam

    Energy Technology Data Exchange (ETDEWEB)

    Josypčuk, Bohdan, E-mail: josypcuk@jh-inst.cas.cz [J. Heyrovský Institute of Physical Chemistry of AS CR, v.v.i., Department of Biophysical Chemistry, Dolejskova 3, Prague (Czech Republic); Barek, Jiří [Charles University in Prague, Faculty of Science, University Center of Excellence UNCE “Supramolecular Chemistry”, Department of Analytical Chemistry, UNESCO Laboratory of Environmental Electrochemistry, Albertov 6, CZ-128 43 Prague 2 (Czech Republic); Josypčuk, Oksana [J. Heyrovský Institute of Physical Chemistry of AS CR, v.v.i., Department of Biophysical Chemistry, Dolejskova 3, Prague (Czech Republic); Charles University in Prague, Faculty of Science, University Center of Excellence UNCE “Supramolecular Chemistry”, Department of Analytical Chemistry, UNESCO Laboratory of Environmental Electrochemistry, Albertov 6, CZ-128 43 Prague 2 (Czech Republic)

    2013-05-17

    Graphical abstract: -- Highlights: •Flow amperometric enzymatic biosensor was constructed. •The biosensor is based on a reactor of a novel material – porous silver solid amalgam. •Tubular amalgam detector was used for determination of decrease of O{sub 2} concentration. •Covalent bonds amalgam−thiol−enzyme contributed to the sensor long-term stability. •LOD of glucose was 0.01 mmol L{sup −1} with RSD = 1.3% (n = 11). -- Abstract: A flow amperometric enzymatic biosensor for the determination of glucose was constructed. The biosensor consists of a flow reactor based on porous silver solid amalgam (AgSA) and a flow tubular detector based on compact AgSA. The preparation of the sensor and the determination of glucose occurred in three steps. First, a self-assembled monolayer of 11-mercaptoundecanoic acid (MUA) was formed at the porous surface of the reactor. Second, enzyme glucose oxidase (GOx) was covalently immobilized at MUA-layer using N-ethyl-N′-(3-dimethylaminopropyl) carboimide and N-hydroxysuccinimide chemistry. Finally, a decrease of oxygen concentration (directly proportional to the concentration of glucose) during enzymatic reaction was amperometrically measured on the tubular detector under flow injection conditions. The following parameters of glucose determination were optimized with respect to amperometric response: composition of the mobile phase, its concentration, the potential of detection and the flow rate. The calibration curve of glucose was linear in the concentration range of 0.02–0.80 mmol L{sup −1} with detection limit of 0.01 mmol L{sup −1}. The content of glucose in the sample of honey was determined as 35.5 ± 1.0 mass % (number of the repeated measurements n = 7; standard deviation SD = 1.2%; relative standard deviation RSD = 3.2%) which corresponds well with the declared values. The tested biosensor proved good long-term stability (77% of the current response of glucose was retained after 35 days)

  1. Measures and experiments to the reduction of mercury in the waste recycling plant Bonn. The gold amalgam procedure - Attempt of precipitation in the scrubber with TMT 15 - enrichment of the Dioxorb absorbent with activated charcoal; Massnahmen und Versuche zur Quecksilberminderung in der Abfallverwertungsanlage Bonn. Das Gold-Amalgamverfahren: Faellungsversuch im Waescher mit TMT 15 - Anreicherung des Dioxorb-Absorbens mit Aktivkohle

    Energy Technology Data Exchange (ETDEWEB)

    Heidrich, R. [Muellverwertungsanlage Bonn GmbH, Bonn (Germany)

    2007-07-01

    MVA Bonn GmbH (Bonn, Federal Republic of Germany) operates a plant for the thermal utilization of settlement wastes. The author of the contribution under consideration reports on measures and attempts according to the reduction of mercury in the waste processing plant Bonn. In particular, three procedures are discussed: (a) The gold amalgam procedure; (b) attempt of precipitation in the scrubber with TMT-15; (c) enrichment of the adsorbent Dioxorb with activated charcoal. The gold amalgam procedure is a reliable procedure for the reduction of the mercury content in exhaust gases. Additionally, it is a very expensive procedure. The filling material containers of all three procedures should be replaced in the next revisions gradually with new containers. The danger of an enrichment of considerable quantities of mercury on the filling material packing is large. A further possibility is the filling of the finished solution over a mist eliminator. Here the danger of the blockage plays a substantial role. A thorough and reliable lowering of the mercury emission can be achieved by means of the active charcoal containing Dioxorb.

  2. Differential metallothionein expression in oral lichen planus and amalgam-associated oral lichenoid lesions.

    Science.gov (United States)

    Mendes, G-G; Servato, J-P-S; Borges, F-C; Rosa, R-R; Siqueira, C-S; de Faria, P-R; Loyola, A-M; Cardoso, S-V

    2018-05-01

    Oral lichen planus (OLP) is a chronic inflammatory disease mediated by T cells, which manifests as reticular (white) or erosive (red) lesions, that are eventually painful. Oral lichenoid lesion (OLL) are distinguished from OLP by the presence of precipitating factors. The aim of this study was to evaluate whether the presence of metallothionein, which is involved in anti-apoptotic pathways and the anti-oxidative response, could serve as a differential diagnostic for OLP and OLL. We evaluated the expression of metallothionein in 40 cases of OLP and 20 cases of OLL using immunohistochemistry. White OLP has higher concentrations of metallothionein than red OLP in basal and parabasal layers. Moreover, metallothionein was more frequently observed in the cytoplasm and nuclei of basal cells in OLP patients compared to the same regions of OLL cases. Metallothionein levels are related to OLP severity and may contribute to a differential diagnosis between OLP and OLL.

  3. Voltammetric determination of the herbicide Bifenox in drinking and river water using a silver solid amalgam electrode

    Czech Academy of Sciences Publication Activity Database

    Barek, J.; Cabalková, D.; Fischer, J.; Navrátil, Tomáš; Pecková, K.; Josypčuk, Bohdan

    2011-01-01

    Roč. 9, č. 1 (2011), s. 83-86 ISSN 1610-3653 R&D Projects: GA ČR GA203/07/1195 Institutional research plan: CEZ:AV0Z40400503 Keywords : differential pulse voltammetry * silver solid amalgam electrode * solid phase extraction Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.881, year: 2011

  4. Construction and Application of Flow Enzymatic Biosensor Based of Silver Solid Amalgam Electrode for Determination of Sarcosine

    Czech Academy of Sciences Publication Activity Database

    Josypčuk, Oksana; Barek, J.; Josypčuk, Bohdan

    2015-01-01

    Roč. 27, č. 11 (2015), s. 2559-2566 ISSN 1040-0397 R&D Projects: GA ČR GBP206/12/G151; GA ČR GAP206/11/1638 Institutional support: RVO:61388955 Keywords : biosensors * sarcosine * silver solid amalgam electrode Subject RIV: CG - Electrochemistry Impact factor: 2.471, year: 2015

  5. Six-year success rates of occlusal amalgam and glass-ionomer restorations placed using three minimal intervention approaches.

    NARCIS (Netherlands)

    Mandari, G.J.; Frencken, J.E.F.M.; Hof, M.A. van 't

    2003-01-01

    The present randomised clinical trial was aimed at comparing three minimally invasive restorative treatment approaches for managing dental caries in occlusal surfaces using a non-gamma-2 amalgam and a low-viscosity glass-ionomer as the restorative material. The treatment approaches tested in

  6. Voltammetric Determination of N,N-Dimethyl-4-amine-carboxyazobenzene at a Silver Solid Amalgam Electrode

    Czech Academy of Sciences Publication Activity Database

    Barek, J.; Dodova, E.; Navrátil, Tomáš; Josypčuk, Bohdan; Novotný, Ladislav; Zima, J.

    2003-01-01

    Roč. 15, č. 22 (2003), s. 1778-1781 ISSN 1040-0397 Grant - others:GIT(AR) 101/02/U111/CZ Institutional research plan: CEZ:AV0Z4040901 Keywords : N,N-dimethyl-4-amino-carboxyazobenzene * differential pulse voltammetry * silver solid amalgam electrode Subject RIV: CG - Electrochemistry Impact factor: 1.811, year: 2003

  7. Radiopacity of root filling materials

    International Nuclear Information System (INIS)

    Beyer-Olsen, E.M.

    1983-01-01

    A method for measuring the radiopacity of root filling materials is described. Direct measurements were made of the optic density values of the materials in comparison with a standard curve relating optic density to the thickness of an aluminium step wedge exposed simultaneously. By proper selection of film and conditions for exposure and development, it was possible to obtain a near-linear standard curve which added to the safety and reproducibility of the method. The technique of radiographic assessment was modified from clinical procedures in evaluating the obturation in radiographs, and it was aimed at detecting slits or voids between the dental wall and the filling material. This radiographic assessment of potensial leakage was compared with actual in vitro lekage of dye (basic fuchsin) into the roots of filled teeth. The result of the investigation show that root filling materials display a very wide range of radiopacity, from less than 3 mm to more than 12 mm of aluminium. It also seem that tooth roots that appear to be well obturated by radiographic evaluation, stand a good chance of beeing resistant to leakage in vitro, and that the type of filling material rather than its radiographic appearance, determines the susceptibility of the filled tooth to leakage in vitro. As an appendix the report contains a survey of radiopaque additives in root filling materials

  8. Occlusal glass ionomer cermet, resin sandwich and amalgam restorations: a 2-year clinical study.

    Science.gov (United States)

    Lidums, A; Wilkie, R; Smales, R

    1993-08-01

    This study compared the clinical behavior of a glass ionomer silver cermet (Ketac-Silver), a posterior resin composite (Visio-Molar) used with the "sandwich" technique, and a high-copper amalgam (Dispersalloy) for restoring conventional Class I occlusal cavity preparations. Two dentists placed 116 restorations in the posterior permanent teeth of 35 adults treated at a dental hospital. Restorations were assessed at 6-month intervals over 2 years for bulk loss of material and occlusal wear, surface voids, roughness and cracking, surface and marginal staining, and marginal fracture. Losses of material and surface voids were obvious with the cermet material, with surface crazing or cracking being present in 33% of the restorations. The cermet cannot be recommended as a long-term permanent restorative material if the restorations are likely to be subjected to heavy occlusal stresses and abrasive wear.

  9. Amalgamation of Chlamydia pneumoniae inclusions with lipid droplets in foam cells in human atherosclerotic plaque.

    Science.gov (United States)

    Bobryshev, Yuri V; Killingsworth, Murray C; Tran, Dihn; Lord, Reginald

    2008-07-01

    Chlamydia pneumoniae (Chlamydophila pneumoniae) infect macrophages and accelerates foam cell formation in in vitro experiments, but whether this might occur in human atherosclerosis is unknown. In the present study, we examined 17 carotid artery segments, obtained by endarterectomy, in which the presence of C. pneumoniae was confirmed by both polymerase chain reaction and immunohistochemistry. Electron microscopy demonstrated the presence of structures with the appearance of elementary, reticulate and aberrant bodies of C. pneumoniae in the cytoplasm of macrophage foam cells. The volume of the cytoplasm that was free from vacuoles and lipid droplets in C. pneumoniae-infected foam cells was dramatically reduced, and a phenomenon of the amalgamation of C. pneumoniae inclusions with lipid droplets was detected. Double immunohistochemistry showed that C. pneumoniae-infected foam cells contained a large number of oxidized low-density lipoproteins. The observations provide support to the hypothesis that C. pneumoniae could affect foam cell formation in human atherosclerosis.

  10. Design and evaluation of a filter-based chairside amalgam separation system

    Energy Technology Data Exchange (ETDEWEB)

    Stone, Mark E. [Naval Institute for Dental and Biomedical Research, 310A B Street, Great Lakes, Illinois 60088 (United States)], E-mail: mark.stone@yahoo.com; Cohen, Mark E.; Berry, Denise L.; Ragain, James C. [Naval Institute for Dental and Biomedical Research, 310A B Street, Great Lakes, Illinois 60088 (United States)

    2008-06-15

    This study evaluated the ability of a chairside filtration system to remove particulate-based mercury (Hg) from dental-unit wastewater. Prototypes of the chairside filtration system were designed and fabricated using reusable filter chambers with disposable filter elements. The system was installed in five dental operatories utilizing filter elements with nominal pore sizes of 50{mu}m, 15{mu}m, 1{mu}m, 0.5{mu}m, or with no system installed (control). Daily chairside wastewater samples were collected on ten consecutive days from each room and brought to the laboratory for processing. After processing the wastewater samples, Hg concentrations were determined with cold vapor atomic absorption spectrometry (USEPA method 7470A). Filter systems were exchanged after ten samples were collected so that all five of the configurations were evaluated in each room (with assignment order balanced by a Latin Square). The numbers of surfaces of amalgam placed and removed per day were tracked in each room. In part two, new filter systems with the 0.5{mu}m filter elements were installed in the five dental operatories and vacuum levels at the high-velocity evacuation cannula tip were measured with a vacuum gauge. In part three of the study, the chairside filtration system utilizing 0.5{mu}m and 15{mu}m filter elements was evaluated utilizing the ISO 11143 testing protocol, a laboratory test of amalgam separator efficiency utilizing amalgam samples of known particle size distribution. Mean Hg per chair per day (no filter installed) was 1087.38mg (SD = 993.92mg). Mean Hg per chair per day for the 50{mu}m, 15{mu}m, 1{mu}m, 0.5{mu}m filter configurations was 79.13mg (SD = 71.40mg), 23.55mg (SD = 23.25mg), 17.68mg (SD = 17.35mg), and 4.25mg (SD = 6.35mg), respectively (n = 50 for all groups). Calculated removal efficiencies from the clinical samples were 92.7%, 97.8%, 98.4%, and 99.6%, respectively. ANCOVA on data from the four filter groups, with amalgam-surfaces-removed included as a

  11. Towards a computational- and algorithmic-level account of concept blending using analogies and amalgams

    Science.gov (United States)

    Besold, Tarek R.; Kühnberger, Kai-Uwe; Plaza, Enric

    2017-10-01

    Concept blending - a cognitive process which allows for the combination of certain elements (and their relations) from originally distinct conceptual spaces into a new unified space combining these previously separate elements, and enables reasoning and inference over the combination - is taken as a key element of creative thought and combinatorial creativity. In this article, we summarise our work towards the development of a computational-level and algorithmic-level account of concept blending, combining approaches from computational analogy-making and case-based reasoning (CBR). We present the theoretical background, as well as an algorithmic proposal integrating higher-order anti-unification matching and generalisation from analogy with amalgams from CBR. The feasibility of the approach is then exemplified in two case studies.

  12. Some physico-chemical and radiation properties of plutonium-238 metal prepared by electrochemical amalgamation

    Energy Technology Data Exchange (ETDEWEB)

    Peretrukhin, V.F. [A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31 Leninsky Prospect, Moscow 119991 (Russian Federation)], E-mail: vperet@ipc.rssi.ru; Rovny, S.I. [Production Association ' Mayak' , 31 Prospect Lenin, Ozersk, Chelyabinsk Region 456784 (Russian Federation); Maslennikov, A.G. [A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31 Leninsky Prospect, Moscow 119991 (Russian Federation); Ershov, V.V.; Chinenov, P.P.; Kapitonov, V.I.; Kuvaev, V.L. [Production Association ' Mayak' , 31 Prospect Lenin, Ozersk, Chelyabinsk Region 456784 (Russian Federation)

    2007-10-11

    Pu-238 metal was prepared by electrolytic amalgamation from Pu(III) acetate aqueous solution and by followed by the thermal decomposition of the Pu amalgam. The density, specific heat power, {gamma}-spectra, neutron flux, and corrosion kinetics in dry air at ambient temperature of the prepared {sup 238}Pu metal were measured. The neutron flux and {gamma}-spectra from {sup 238}Pu metal have been attributed to spontaneous and induced fission and to ({alpha},{alpha}'{gamma}), ({alpha},p{gamma}), and ({alpha},n{gamma}) nuclear reactions on light nuclei. The electrochemically prepared {sup 238}Pu metal was shown to generate fewer neutrons, produce less gamma radiation, and contains lower {sup 10}B, {sup 19}F, and {sup 28}Si impurities in comparison with biomedical {sup 238}PuO{sub 2}. The increase of neutron flux from the sample due to the reaction {sup 18}O({alpha},n{gamma}) {sup 21}Ne was shown to be proportional to the increase of the mass of the {sup 238}Pu metal with time due to corrosion in dry air. {sup 238}Pu metal corrosion rate maximum and average values (1.1 x 10{sup -2} and 4.7 x 10{sup -3} mg cm{sup -2} h{sup -1}, respectively) obtained in dry air were an order of magnitude higher than the rates published for {sup 239}Pu under similar experiment conditions. The difference between the {sup 239}Pu and {sup 238}Pu metal corrosion rate and mechanism is proposed to be due to the greater radiation effects and temperature on the {sup 238}Pu surface.

  13. The Gd14Ag51 structure type and its relation to some complex amalgam structures

    International Nuclear Information System (INIS)

    Tambornino, Frank; Sappl, Jonathan; Hoch, Constantin

    2015-01-01

    Highlights: • The Gd 14 Ag 51 structure type has been revisited on the basis of single crystal diffraction data. • Symmetry analysis from electron density and TEM shows the space group P6/m to be true. • Gd 14 Ag 51 shows good metallic behaviour. • Structure relations to alkali, alkaline-earth and rare-earth metal amalgams can be established. • Complexity values for the RE 14 Ag 51 structure family were calculated. - Abstract: A plethora of binary and ternary intermetallic compounds has been assigned to the Gd 14 Ag 51 structure type, crystallising in the hexagonal system (space group P6/m, a = 1264.30(18) pm, c = 933.58(11) pm for Gd 14 Ag 51 ). Starting in the late 1960s, much work has been invested in the structural elucidation of these crystal structures. However, reliable single crystal data are scarce, and most structure type assignments have been performed merely on the basis of powder data. We have redetermined four representatives of the binary RE 14 Ag 51 structure type (RE = Y, Ce, Gd, Tb) with modern high-precision single crystal X-ray methods. The assignment of the Gd 14 Ag 51 structure type to space group P6/m was additionally verified by careful analysis of high resolution transmission electron micrographs. We emphasise the close relation of the Gd 14 Ag 51 structure type to the structures of some recently described amalgams of similar composition focussing on disorder phenomena and structural complexity. Furthermore, we provide detailed information on synthesis as well as electrical and magnetic properties for Gd 14 Ag 51 , the parent compound of this structure family

  14. Better building of valley fills

    Energy Technology Data Exchange (ETDEWEB)

    Chironis, N.P.

    1980-03-01

    Current US regulations for building valley fills or head of hollow fills to hold excess spoil resulting from contour mining are meeting with considerable opposition, particularly from operators in steep-slope areas. An alternative method has been submitted to the Office of Surface Mining by Virgina. Known as the zoned concept method, it has already been used successfully in building water-holding dams and coal refuse embankments on sloping terrain. The ways in which drainage and seepage are managed are described.

  15. The differences in Hg content released from high copper amalgam and silverfil argentum restoration into artificial saliva after one week of soaking (in vitro

    Directory of Open Access Journals (Sweden)

    Deriz Rieskanoerbachra Wisuardy

    2008-07-01

    Full Text Available Dental restoration is a treatment in dentistry that very often implemented. One of the restoration materials used is an amalgam. Amalgam has some deficiencies, among others, the presence of free Hg. The purpose of this study was to find out the difference in Hg content released from two different kinds of amalgam, namely, high copper amalgam and silverfil argentum carried out in vitro. This study was carried out on thirty premolar teeth of the maxilla which underwent class one occlusal restoration. The Hg content released was measured using the Atomic Absorption Spectrophotometry (AAS. This was a quasi-experimental study. The study results analyzed using the independent t paired statistical test method indicated that after one week of immersion, the average Hg content released from high copper amalgam restoration was 10,695 ng/mL and from silverfil argentum restoration was 5,602 ng/mL. The conclusion of the study was that there was a difference in Hg content released from high copper amalgam restoration and silverfil argentum restoration. The Hg content released from high copper amalgam restoration was higher than the Hg content released from silverfil argentum restoration.

  16. Perioral Dermatitis after Dental Filling in a 12-Year-Old Girl: Involvement of Cholinergic System in Skin Neuroinflammation?

    Directory of Open Access Journals (Sweden)

    Fabrizio Guarneri

    2008-01-01

    Full Text Available The etiopathogenesis of perioral dermatitis (PD is still unknown and, consequently, medical treatment is difficult, not precisely defined, and often unsatisfactory. On the basis of a peculiar case that appeared soon after multiple dental fillings with a mercury-containing amalgam, we proposed that neurogenic inflammation could play a role in the pathogenesis of PD. According to the new findings provided by clinical and basic research, neurogenic inflammation has a relevant part in the pathogenesis of many cutaneous diseases. We report a similar case of PD, taking into account, more specifically, the possible involvement of the cholinergic system. Also in this case, PD seems to be mainly related to the mercury contained in dental fillings and/or its organic compounds formed by oral/gut bacteria. We examined the possible role of these substances as causes of PD, providing new information on the possible cross-talk between neuroimmunodermatology and potential triggers of PD.

  17. QENS investigation of filled rubbers

    CERN Document Server

    Triolo, A; Desmedt, A; Pieper, J K; Lo Celso, F; Triolo, R; Negroni, F; Arrighi, V; Qian, H; Frick, B

    2002-01-01

    The polymer segmental dynamics is investigated in a series of silica-filled rubbers. The presence of inert fillers in polymers greatly affects the mechanical and physical performance of the final materials. For example, silica has been proposed as a reinforcing agent of elastomers in tire production. Results from quasielastic neutron scattering and Dynamic Mechanical Thermal Analysis (DMTA) measurements are presented on styrene-ran-butadiene rubber filled with silica. A clear indication is obtained of the existence of a bimodal dynamics, which can be rationalized in terms of the relaxation of bulk rubber and the much slower relaxation of the rubber adsorbed on the filler surface. (orig.)

  18. Gas-Filled Capillary Model

    International Nuclear Information System (INIS)

    Steinhauer, L. C.; Kimura, W. D.

    2006-01-01

    We have developed a 1-D, quasi-steady-state numerical model for a gas-filled capillary discharge that is designed to aid in selecting the optimum capillary radius in order to guide a laser beam with the required intensity through the capillary. The model also includes the option for an external solenoid B-field around the capillary, which increases the depth of the parabolic density channel in the capillary, thereby allowing for propagation of smaller laser beam waists. The model has been used to select the parameters for gas-filled capillaries to be utilized during the Staged Electron Laser Acceleration -- Laser Wakefield (STELLA-LW) experiment

  19. A Tale of Amalgamation of Three Permo-Triassic Collage Systems in Central Asia: Oroclines, Sutures, and Terminal Accretion

    Science.gov (United States)

    Xiao, Wenjiao; Windley, Brian F.; Sun, Shu; Li, Jiliang; Huang, Baochun; Han, Chunming; Yuan, Chao; Sun, Min; Chen, Hanlin

    2015-05-01

    The Central Asian Orogenic Belt records the accretion and convergence of three collage systems that were finally rotated into two major oroclines. The Mongolia collage system was a long, N-S-oriented composite ribbon that was rotated to its current orientation when the Mongol-Okhotsk orocline was formed. The components of the Kazakhstan collage system were welded together into a long, single composite arc that was bent to form the Kazakhstan orocline. The cratons of Tarim and North China were united and sutured by the Beishan orogen, which terminated with formation of the Solonker suture in northern China. All components of the three collage systems were generated by the Neoproterozoic and were amalgamated in the Permo-Triassic. The Central Asian Orogenic Belt evolved by multiple convergence and accretion of many orogenic components during multiple phases of amalgamation, followed by two phases of orocline rotation.

  20. Use of polished and mercury film-modified silver solid amalgam electrodes in electrochemical analysis of DNA

    Czech Academy of Sciences Publication Activity Database

    Fadrná, Renata; Cahová, Kateřina; Havran, Luděk; Josypčuk, Bohdan; Fojta, Miroslav

    2005-01-01

    Roč. 17, 5-6 (2005), s. 452-459 ISSN 1040-0397 R&D Projects: GA MPO 1H-PK/42; GA ČR GA203/04/1325; GA AV ČR KJB4004302 Institutional research plan: CEZ:AV0Z40400503; CEZ:AV0Z50040507 Keywords : DNA electrochemistry * solid amalgam electrodes * mercury film electrodes * DNA damage Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.189, year: 2005

  1. Voltammetric Determination of Genotoxic Nitro Derivatives of Fluorene and 9-Fluorenone Using a Mercury Meniscus Modified Silver Solid Amalgam Electrode

    Czech Academy of Sciences Publication Activity Database

    Vyskočil, V.; Navrátil, Tomáš; Polášková, P.; Barek, J.

    2010-01-01

    Roč. 22, 17-18 (2010), s. 2034-2042 ISSN 1040-0397. [International Conference on Modern Electroanalytical Methods. Prague, 09.12.2009-14.12.2009] R&D Projects: GA AV ČR IAA400400806 Institutional research plan: CEZ:AV0Z40400503 Keywords : voltammetry * Silver solid amalgam electrode * drinking water Subject RIV: CG - Electrochemistry Impact factor: 2.721, year: 2010

  2. Study of tin amalgam mirrors by {sup 119}Sn Mössbauer spectroscopy and other analytical methods

    Energy Technology Data Exchange (ETDEWEB)

    Lerf, A. [Bavarian Academy of Sciences, Walther Meißner Institute (Germany); Wagner, F. E., E-mail: fwagner@tum.de [Technical University of Munich, Physics Department E15 (Germany); Herrera, L. K. [Universidad Nacional de Colombia. Dpto. de Ingeniería Mecánica y Mecatrónica (Colombia); Justo, A.; Mu noz-Páez, A.; Pérez-Rodríguez, J. L. [University of Sevilla-CSIC, ICMSE (Spain)

    2016-12-15

    From the beginning of the 16 {sup th} until the end of the 19 {sup th} century the most widely used mirrors consisted of a pane of glass backed with a reflecting layer of tin-mercury amalgam. They were made by sliding the glass pane over a tin foil covered with liquid mercury. After removal of the superfluous mercury, tin amalgam formed slowly at ambient temperature and yielded a reflecting layer adhering to the surface of the glass. Such mirrors often deteriorate in the course of time by oxidation of the tin in the amalgam to stannous or stannic oxide. {sup 119}Sn Mössbauer spectroscopy, scanning electron microscopy, micro-XRF and X-ray diffraction have been used to study this deterioration process. The studied specimens were a modern mirror made for the reconstruction of the Green Vault in Dresden in the early 2000s, two rather well preserved German mirrors from the 17 {sup th} and 19 {sup th} centuries and several strongly deteriorated specimens of Baroque mirrors from the south of Spain. The modern mirror consists mainly of a Sn{sub 0.9}Hg{sub 0.1} amalgam with only 2 % of SnO{sub 2}. The older German mirrors showed more pronounced oxidation, containing 12 and 15 % of SnO{sub 2}, which did not noticeably impair their reflectivity. In the samples from the Spanish mirrors at best a few percent of metallic phase was left. The majority of the tin had oxidised to SnO{sub 2}, but between 8 and 20 % of the tin was present as SnO. X-ray diffraction yielded similar results and micro-XRF mapping using synchrotron radiation for excitation gave information on the distribution of Sn and Hg in the reflecting layer of the mirrors.

  3. Study of tin amalgam mirrors by "1"1"9Sn Mössbauer spectroscopy and other analytical methods

    International Nuclear Information System (INIS)

    Lerf, A.; Wagner, F. E.; Herrera, L. K.; Justo, A.; Mu noz-Páez, A.; Pérez-Rodríguez, J. L.

    2016-01-01

    From the beginning of the 16 "t"h until the end of the 19 "t"h century the most widely used mirrors consisted of a pane of glass backed with a reflecting layer of tin-mercury amalgam. They were made by sliding the glass pane over a tin foil covered with liquid mercury. After removal of the superfluous mercury, tin amalgam formed slowly at ambient temperature and yielded a reflecting layer adhering to the surface of the glass. Such mirrors often deteriorate in the course of time by oxidation of the tin in the amalgam to stannous or stannic oxide. "1"1"9Sn Mössbauer spectroscopy, scanning electron microscopy, micro-XRF and X-ray diffraction have been used to study this deterioration process. The studied specimens were a modern mirror made for the reconstruction of the Green Vault in Dresden in the early 2000s, two rather well preserved German mirrors from the 17 "t"h and 19 "t"h centuries and several strongly deteriorated specimens of Baroque mirrors from the south of Spain. The modern mirror consists mainly of a Sn_0_._9Hg_0_._1 amalgam with only 2 % of SnO_2. The older German mirrors showed more pronounced oxidation, containing 12 and 15 % of SnO_2, which did not noticeably impair their reflectivity. In the samples from the Spanish mirrors at best a few percent of metallic phase was left. The majority of the tin had oxidised to SnO_2, but between 8 and 20 % of the tin was present as SnO. X-ray diffraction yielded similar results and micro-XRF mapping using synchrotron radiation for excitation gave information on the distribution of Sn and Hg in the reflecting layer of the mirrors.

  4. Verification of Applicability of Mercury Meniscus Modified Silver Solid Amalgam Electrode for Determination of Heavy Metals in Plant matrices

    Czech Academy of Sciences Publication Activity Database

    Čížková, P.; Navrátil, Tomáš; Šestáková, Ivana; Josypčuk, Bohdan

    2007-01-01

    Roč. 19, 2-3 (2007), s. 161-171 ISSN 1040-0397 R&D Projects: GA MPO 1H-PK/42; GA ČR GA521/06/0496 Institutional research plan: CEZ:AV0Z40400503 Keywords : voltammetry * biological materials * solid amalgam electrode * atomic absorption spectroscopy Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.949, year: 2007

  5. Voltammetric determination of trace amounts of 2-methyl-4,6-dinitrophenol at a silver solid amalgam electrode

    Czech Academy of Sciences Publication Activity Database

    Fischer, J.; Barek, J.; Josypčuk, Bohdan; Navrátil, Tomáš

    2006-01-01

    Roč. 18, č. 2 (2006), s. 127-130 ISSN 1040-0397 R&D Projects: GA ČR GA203/03/0182; GA MPO 1H-PK/42 Institutional research plan: CEZ:AV0Z40400503 Keywords : 2-methyl-4,6-dinitrophenol * differential pulse voltammetry * silver solid amalgam electrode Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.444, year: 2006

  6. Filling of charged cylindrical capillaries

    NARCIS (Netherlands)

    Das, Siddhartha; Chanda, Sourayon; Eijkel, J.C.T.; Tas, N.R.; Chakraborty, Suman; Mitra, Sushanta K.

    2014-01-01

    We provide an analytical model to describe the filling dynamics of horizontal cylindrical capillaries having charged walls. The presence of surface charge leads to two distinct effects: It leads to a retarding electrical force on the liquid column and also causes a reduced viscous drag force because

  7. Space-filling polyhedral sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Haaland, Peter

    2016-06-21

    Solid sorbents, systems, and methods for pumping, storage, and purification of gases are disclosed. They derive from the dynamics of porous and free convection for specific gas/sorbent combinations and use space filling polyhedral microliths with facial aplanarities to produce sorbent arrays with interpenetrating interstitial manifolds of voids.

  8. Clinical anatomy of the subserous layer: An amalgamation of gross and clinical anatomy.

    Science.gov (United States)

    Yabuki, Yoshihiko

    2016-05-01

    The 1998 edition of Terminologia Anatomica introduced some currently used clinical anatomical terms for the pelvic connective tissue or subserous layer. These innovations persuaded the present author to consider a format in which the clinical anatomical terms could be reconciled with those of gross anatomy and incorporated into a single anatomical glossary without contradiction or ambiguity. Specific studies on the subserous layer were undertaken on 79 Japanese women who had undergone surgery for uterine cervical cancer, and on 26 female cadavers that were dissected, 17 being formalin-fixed and 9 fresh. The results were as follows: (a) the subserous layer could be segmentalized by surgical dissection in the perpendicular, horizontal and sagittal planes; (b) the segmentalized subserous layer corresponded to 12 cubes, or ligaments, of minimal dimension that enabled the pelvic organs to be extirpated; (c) each ligament had a three-dimensional (3D) structure comprising craniocaudal, mediolateral, and dorsoventral directions vis-á-vis the pelvic axis; (d) these 3D-structured ligaments were encoded morphologically in order of decreasing length; and (e) using these codes, all the surgical procedures for 19th century to present-day radical hysterectomy could be expressed symbolically. The establishment of clinical anatomical terms, represented symbolically through coding as demonstrated in this article, could provide common ground for amalgamating clinical anatomy with gross anatomy. Consequently, terms in clinical anatomy and gross anatomy could be reconciled and compiled into a single anatomical glossary. © 2015 Wiley Periodicals, Inc.

  9. Amalgamation of management information system into anaesthesiology practice: A boon for the modern anaesthesiologists

    Directory of Open Access Journals (Sweden)

    Sukhminder Jit Singh Bajwa

    2014-01-01

    Full Text Available Over the years, traditional anaesthesia record keeping system has been the backbone of anaesthesiology ever since its introduction in the 1890s by Dr. Harvey Cushing and Dr. Ernest A. Codman. Besides providing the important information regarding patients′ vital physiologic parameters, paper records had been a reliable source for various clinical research activities. The introduction of electronic monitoring gadgets and electronic record keeping systems has revolutionised the anaesthesiology practice to a large extent. Recently, the introduction of anaesthesia information management system (AIMS, which incorporates all the features of monitoring gadgets, such as electronic storage of large accurate data, quality assurance in anaesthesia, enhancing patient safety, ensuring legal protection, improved billing services and effecting an organisational change, is almost a revolution in modern-day anaesthesiology practice. The clinical research activities that are responsible for taking anaesthesiology discipline to higher peaks have also been boosted by the amalgamation of AIMS, enabling multicenter studies and sharing of clinical data. Barring few concerns in its installation, cost factors and functional aspects, the future of AIMS seems to be bright and will definitely prove to be a boon for modern-day anaesthesiology practice.

  10. A comparison between new dentinal adhesives (fifth generation and traditional varnish in microleakage reduction of amalgam restorations in primary teeth

    Directory of Open Access Journals (Sweden)

    Mortazavi M. Associate Professor

    2003-06-01

    Full Text Available Statement of Problem: Microleakage presents the major cause for restorations failure in the oral cavity resulting in postoperative sensitivity, pulp irritation and secondary caries formation."nAim: The aim of this study was to compare two dentinal adhesive systems of fifth generation and copalite varnish in reducing microleakage of amalgam restorations in primary teeth."nMaterials and Methods: In this in-vitro study, 100 class V amalgam restorations were prepared on the buccal or lingual surfaces of primary molar and canine teeth. Samples were randomly divided into four groups (25 samples each. No liner was used for the first group and the second group restorations were lined with copalite varnish. Two dentin adhesives, called Syntac C and Single Bond, were used for the third and fourth groups, respectively. At the next stage, the samples were immersed in 5% fuschin solution for 24 hours, then sectioned buccolingually, and examined under a stereomicroscope for microleakage evaluation."nResults: There was a significant difference between four groups statistically (PO.000I, Comparing"nfour groups, the first and fourth ones, demonstrated the most and the least microleakage, respectively."nConclusion: The present study showed that new dentinal adhesive systems caused microleakage"nreduction in amalgam restorations of primary teeth.

  11. Validity and reliability of methods for the detection of secondary caries around amalgam restorations in primary teeth

    Directory of Open Access Journals (Sweden)

    Mariana Minatel Braga

    2010-03-01

    Full Text Available Secondary caries has been reported as the main reason for restoration replacement. The aim of this in vitro study was to evaluate the performance of different methods - visual inspection, laser fluorescence (DIAGNOdent, radiography and tactile examination - for secondary caries detection in primary molars restored with amalgam. Fifty-four primary molars were photographed and 73 suspect sites adjacent to amalgam restorations were selected. Two examiners evaluated independently these sites using all methods. Agreement between examiners was assessed by the Kappa test. To validate the methods, a caries-detector dye was used after restoration removal. The best cut-off points for the sample were found by a Receiver Operator Characteristic (ROC analysis, and the area under the ROC curve (Az, and the sensitivity, specificity and accuracy of the methods were calculated for enamel (D2 and dentine (D3 thresholds. These parameters were found for each method and then compared by the McNemar test. The tactile examination and visual inspection presented the highest inter-examiner agreement for the D2 and D3 thresholds, respectively. The visual inspection also showed better performance than the other methods for both thresholds (Az = 0.861 and Az = 0.841, respectively. In conclusion, the visual inspection presented the best performance for detecting enamel and dentin secondary caries in primary teeth restored with amalgam.

  12. Hard-to-fill vacancies.

    Science.gov (United States)

    Williams, Ruth

    2010-09-29

    Skills for Health has launched a set of resources to help healthcare employers tackle hard-to-fill entry-level vacancies and provide sustainable employment for local unemployed people. The Sector Employability Toolkit aims to reduce recruitment and retention costs for entry-level posts and repare people for employment through pre-job training programmes, and support employers to develop local partnerships to gain access to wider pools of candidates and funding streams.

  13. Determination of mercury in hair: Comparison between gold amalgamation-atomic absorption spectrometry and mass spectrometry.

    Science.gov (United States)

    Domanico, Francesco; Forte, Giovanni; Majorani, Costanza; Senofonte, Oreste; Petrucci, Francesco; Pezzi, Vincenzo; Alimonti, Alessandro

    2017-09-01

    Mercury is a heavy metal that causes serious health problems in exposed subjects. The most toxic form, i.e., methylmercury (MeHg), is mostly excreted through human hair. Numerous analytical methods are available for total Hg analysis in human hair, including cold vapour atomic fluorescence spectrometry (CV-AFS), inductively coupled plasma mass spectrometry (ICP-MS) and thermal decomposition amalgamation atomic absorption spectrometry (TDA-AAS). The aim of the study was to compare the TDA-AAS with the ICP-MS in the Hg quantification in human hair. After the washing procedure to minimize the external contamination, from each hair sample two aliquots were taken; the first was used for direct analysis of Hg by TDA-AAS and the second was digested for Hg determination by the ICP-MS. Results indicated that the two data sets were fully comparable (median; TDA-AAS, 475ngg -1 ; ICP-MS, 437ngg -1 ) and were not statistically different (Mann-Whitney test; p=0.44). The two techniques presented results with a good coefficient of correlation (r=0.94) despite different operative ranges and method limits. Both techniques satisfied internal performance requirements and the parameters for method validation resulting sensitive, precise and reliable. Finally, the use of the TDA-AAS can be considered instead of the ICP-MS in hair analysis in order to reduce sample manipulation with minor risk of contamination, less time consuming due to the absence of the digestion step and cheaper analyses. Copyright © 2016 Elsevier GmbH. All rights reserved.

  14. Extent of tooth decay in the mouth and increased need for replacement of dental restorations: the New England Children's Amalgam Trial.

    Science.gov (United States)

    Trachtenberg, Felicia; Maserejian, Nancy Nairi; Tavares, Mary; Soncini, Jennifer Ann; Hayes, Catherine

    2008-01-01

    The purpose of this study was to assess the relationship between baseline caries experience and the restoration replacement rate in children. The 5-year New England Children's Amalgam Trial recruited 534 6- to 10-year-old children with 2 or more carious posterior teeth. The association between decoy and longevity of restorations was assessed. Restorations with no follow-up (N = 391) were excluded from analysis. The average follow-up was 3.0 +/- 1.6 years in 489 children. Restorations with follow-up (N = 3,604) were placed in mouths with a median of 15 dfs/DFS and 8 dft/DFT. The need for replacement increased significantly (P or = 14 dfs/DFS needed replacement, compared to 9% for 2 to 5 dfs/DFS. Comparing dft/DFT after 5 years of follow-up, there was a 23% replacement rate for > or = 12 dft/DFT compared to 10% for 2 to 3 dft/DFT. Decoy in the mouth had a greater association with the need for replacement due to new caries compared to replacement due to recurrent caries. Children with more decoy at the time of restoration placement were at higher risk for replacement of restorations.

  15. Determination of the metal distribution in tooth fillings in real teeth based on element sensitive X-ray tomography

    International Nuclear Information System (INIS)

    Masschaele, B.; Mondelaers, W.; Cauwels, P.; Jolie, J.; Baechler, S.; Materna, T.

    2000-01-01

    Since a couple of centuries people are using metal tooth-fillings in order to protect their teeth. In the beginning of the 19th century the amalgam or silver fillings were introduced for to first time. Nowadays, dentists mostly use amalgam. These fillings are a mixture of silver, tin and mercury. The mercury which is abundant, about 50%, is dangerous for any living organism. Mercury has a particular affinity for the brain tissue but is also accumulated in the liver, kidneys, lungs, gastrointestinal track and jawbone. Mercury Basely crosses the placenta and is gathered in the heart, pituitary gland and liver of the fetus. It is been proven that the mercury vaporises and enter enters the body via the lungs. Since a couple of years we apply the element sensitive X-ray tomography technique on heavy elements like uranium or lead. By scanning teeth using photons having two different energies, one just below and one just above the K-edge of the element under investigation, the tomography becomes element sensitive. The experiment has been done at the ESRF, beam line ID15A, with a very intense tunable monochromatic high energy X-ray beam. We made tomographies of different teeth with 20 μm image resolution. The slices were 20 μm apart. The results after reconstruction are three dimensional mercury maps which can tell us something about the possibility of mercury diffusion into the roots of the tooth. From there the mercury could enter the blood stream and end up in the organs. (author)

  16. Fissure fillings from Gideaa, central Sweden

    International Nuclear Information System (INIS)

    Tullborg, E.L.; Larsson, S.Aa.

    1983-08-01

    The most frequent fissure filling minerals at Gideaa are calcite, chlorite, pyrite, laumontite, stilbite, smectite, quartz and epidote. Potentially young minerals, i.e. minerals which can be formed during present conditions, are smectite, calcite and quartz, Equilibrium calculations show that these minerals can be stable in the water analysed from Gideaa. In borehole Gi 2, the water exhibits a greater equilibrium with existing minerals in the fissures than water from Gi 4. This is due to the recharge of the water in Gi 4 and discharge of the water in Gi 2. When carbonate saturated water penetrated through the bedrock, calcite precipitated within the more superficial portions of the rock. However, both calcite and zeolite fissures fillings are associated with certain zones in the drill holes. A large number of fractures can be concluded to be of post-Jotnian age. Stilbite, calcite and smectite are associated with these fractures. Laumontite can also be assumed to belong here. The dolerites in the area exhibit a high fracture frequency but a relatively low hydraulic conductivity. This is due to the fact that smectite is very prevalent in the dolerite fractures, Several generations of fracturefilling minerals (above all calcite) have been found in a single fracture. Stable isotope analyses of fissure filling calcites indicate that there are three different groups of calcite. Most of the calcites could not have been precipitated from water of present-day isotope composition at Gideaa, whereas recent calcite may be found in one of the groups. Another group of calcite was precipitated during hydro-thermal conditions.(author)

  17. Selection and specification criteria for fills for cut-and-fill mining

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, E. G.

    1980-05-15

    Because of significant differences in placement and loading conditions, the ideal fill material for a cut-and-fill operation has different characteristics to those for a fill for a filled open stoping operation. The differing requirements of the two mining operations must be understood and accounted for in establishing fill selection and specification criteria. Within the paper, aspects of the particular requirements of cut-and-fill mining are analyzed and related to the specific fill tests and properties required. Emphasis is placed upon the role of fill in ground support, though this cannot be isolated from overall fill performance. Where appropriate, test data are introduced and areas requiring continuing research highlighted.

  18. 30 CFR 817.72 - Disposal of excess spoil: Valley fill/head-of-hollow fills.

    Science.gov (United States)

    2010-07-01

    ... STANDARDS-UNDERGROUND MINING ACTIVITIES § 817.72 Disposal of excess spoil: Valley fill/head-of-hollow fills.... Uncontrolled surface drainage may not be directed over the outslope of the fill. (2) Runoff from areas above the fill and runoff from the surface of the fill shall be diverted into stabilized diversion channels...

  19. Technology of hardening fills for mined spaces

    International Nuclear Information System (INIS)

    Simek, P.; Holas, M.; Chyla, A.; Pech, P.

    1985-01-01

    The technology is described of hardening fills for mined spaces of uranium deposits in North Bohemian chalk. A special equipment was developed for the controlled preparation of a hardening mixture. The composition of the fill is determined by the strength of the filled rock, expecially by the standard strength, i.e., the minimal strength of the filling under uniaxial pressure. The said parameter determines the consumption of binding materials and thereby the total costs of the filling. A description is presented of the filling technology, including rabbit tube transport of the mixture and quality control. (Pu)

  20. Charge balancing fill rate monitor

    International Nuclear Information System (INIS)

    Rothman, J.L.; Blum, E.B.

    1995-01-01

    A fill rate monitor has been developed for the NSLS storage rings to allow machine tuning over a very large dynamic range of beam current. Synchrotron light, focused on a photodiode, produces a signal proportional to the beam current. A charge balancing circuit processes the diode current, creating an output signal proportional to the current injected into the ring. The unit operates linearly over a dynamic range of 120 dB and can resolve pulses of injected beam as small as 1 μA

  1. 3D integrated HYDRA simulations of hohlraums including fill tubes

    Science.gov (United States)

    Marinak, M. M.; Milovich, J.; Hammel, B. A.; Macphee, A. G.; Smalyuk, V. A.; Kerbel, G. D.; Sepke, S.; Patel, M. V.

    2017-10-01

    Measurements of fill tube perturbations from hydro growth radiography (HGR) experiments on the National Ignition Facility show spoke perturbations in the ablator radiating from the base of the tube. These correspond to the shadow of the 10 μm diameter glass fill tube cast by hot spots at early time. We present 3D integrated HYDRA simulations of these experiments which include the fill tube. Meshing techniques are described which were employed to resolve the fill tube structure and associated perturbations in the simulations. We examine the extent to which the specific illumination geometry necessary to accommodate a backlighter in the HGR experiment contributes to the spoke pattern. Simulations presented include high resolution calculations run on the Trinity machine operated by the Alliance for Computing at Extreme Scale (ACES) partnership. This work was performed under the auspices of the Lawrence Livermore National Security, LLC, (LLNS) under Contract No. DE-AC52-07NA27344.

  2. Voltammetric behavior of osmium-labeled DNA at mercury meniscus-modified solid amalgam electrodes. Detecting DNA hybridization

    Czech Academy of Sciences Publication Activity Database

    Josypčuk, Bohdan; Fojta, Miroslav; Havran, Luděk; Heyrovský, Michael; Paleček, Emil

    2006-01-01

    Roč. 18, č. 2 (2006), s. 186-194 ISSN 1040-0397 R&D Projects: GA MPO 1H-PK/42; GA AV ČR IAA4004402; GA AV ČR KJB4004302; GA AV ČR IBS5004355 Institutional research plan: CEZ:AV0Z40400503; CEZ:AV0Z50040507 Keywords : voltammetry * solid amalgam electrodes * DNA-osmium complex * hybridization * catalytic hydrogen evolution Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.444, year: 2006

  3. Bio-inspired dental fillings

    Science.gov (United States)

    Deyhle, Hans; Bunk, Oliver; Buser, Stefan; Krastl, Gabriel; Zitzmann, Nicola U.; Ilgenstein, Bernd; Beckmann, Felix; Pfeiffer, Franz; Weiger, Roland; Müller, Bert

    2009-08-01

    Human teeth are anisotropic composites. Dentin as the core material of the tooth consists of nanometer-sized calcium phosphate crystallites embedded in collagen fiber networks. It shows its anisotropy on the micrometer scale by its well-oriented microtubules. The detailed three-dimensional nanostructure of the hard tissues namely dentin and enamel, however, is not understood, although numerous studies on the anisotropic mechanical properties have been performed and evaluated to explain the tooth function including the enamel-dentin junction acting as effective crack barrier. Small angle X-ray scattering (SAXS) with a spatial resolution in the 10 μm range allows determining the size and orientation of the constituents on the nanometer scale with reasonable precision. So far, only some dental materials, i.e. the fiber reinforced posts exhibit anisotropic properties related to the micrometer-size glass fibers. Dental fillings, composed of nanostructures oriented similar to the natural hard tissues of teeth, however, do not exist at all. The current X-ray-based investigations of extracted human teeth provide evidence for oriented micro- and nanostructures in dentin and enamel. These fundamental quantitative findings result in profound knowledge to develop biologically inspired dental fillings with superior resistance to thermal and mechanical shocks.

  4. Vertical Scan-Conversion for Filling Purposes

    OpenAIRE

    Hersch, R. D.

    1988-01-01

    Conventional scan-conversion algorithms were developed independently of filling algorithms. They cause many problems, when used for filling purposes. However, today's raster printers and plotters require extended use of filling, especially for the generation of typographic characters and graphic line art. A new scan-conversion algorithm, called vertical scan-conversion has been specifically designed to meet the requirements of parity scan line fill algorithms. Vertical scan-conversion ensures...

  5. 7 CFR 58.923 - Filling containers.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Filling containers. 58.923 Section 58.923 Agriculture... Procedures § 58.923 Filling containers. (a) The filling of small containers with product shall be done in a sanitary manner. The containers shall not contaminate or detract from the quality of the product in any way...

  6. [Comparative study of the fracture resistance of sound upper premolars and upper premolars restored with bonded amalgam].

    Science.gov (United States)

    Minto, André Marcelo Peruchi; Dinelli, Welingtom; Nonaka, Tomio; Thome, Luis Henrique de Camargo

    2002-01-01

    The purpose of this in vitro study was to determine the fracture resistance of upper premolars which had received class II preparations (conservative and extensive) and were restored with bonded amalgam, with two different adhesive systems. Seventy teeth were divided in four groups: group 1 (control), with ten sound teeth; group 2, with twenty prepared teeth (10 teeth received conservative cavities and 10, extensive cavities) restored with amalgam without any kind of liner; groups 3 and 4, similar to group 2, though with linings of glass ionomer cement (Vitrebond - 3M) (group 3) and dental adhesive (Scotchbond Multi-Purpose Plus - 3M) (group 4). The teeth were previously fixed in PVC cylinders with acrylic resin. After being restored and thermocycled, the test specimens were submitted to fracture by means of compression in an EMIC-MEM 2000 universal testing machine. After the application of the analysis of variance and complementary Tukey's test, we concluded that the utilized adhesive systems produced an increase of the fracture resistance of teeth presenting with conventional cavities; the teeth presenting with conservative cavities were more resistant in all experimental situations.

  7. Bad metal behaviour in the new Hg-rich amalgam KHg{sub 6} with polar metallic bonding

    Energy Technology Data Exchange (ETDEWEB)

    Tambornino, Frank; Hoch, Constantin, E-mail: constantin.hoch@cup.uni-muenchen.de

    2015-01-05

    Highlights: • The novel Hg-rich amalgam KHg{sub 6} was synthesised by electrocrystallisation. • The structure was investigated by single crystal and powder diffraction. • Thermal decomposition, electric resistance and magnetic susceptibiliy were examined. • Band structure, total and partial density of states and Bader charges were calculated. • Bad metal behaviour results from ionic, metallic and covalent bonding contributions. - Abstract: The new mercury-rich amalgam KHg{sub 6} crystallises with the BaHg{sub 6} structure type (orthorhombic, space group Pnma (No. 62), a = 13.394(9) Å, b = 5.270(3) Å, c = 10.463 Å). It was prepared by electrolysis of a solution of KI in N,N′-Dimethylformamide at 343 K at a reactive Hg cathode. The structure of KHg{sub 6} shows motifs of ionic packing, covalent Hg cluster formation and metallic properties. KHg{sub 6} decomposes peritectically at 443 K. The combination of alkali metals with a noble metal with moderate electron affinity results in the formation of polar metal–metal bonding with considerable but incomplete electron transfer from the electropositive to the electronegative sublattice, resulting in typical “bad metal behaviour”, illustrated by resistance and susceptibility measurements and quantum theoretical calculations.

  8. The simplest representative of a complex series. The Hg-rich amalgam Yb_1_1Hg_5_4

    International Nuclear Information System (INIS)

    Tambornino, Frank; Hoch, Constantin

    2017-01-01

    Yb_1_1Hg_5_4 is a new member of a series of amalgams with composition close to MHg_5. Its crystal structure was solved and refined on the basis of single crystal data. The structure model was confirmed with a Rietveld refinement. Yb_1_1Hg_5_4 has the first crystal structure in this family in which no disorder effects such as mixed occupation, split positions or superstructure formation is observed. It therefore can be regarded as a parent structure for all other amalgams. The crystal structure of Yb_1_1Hg_5_4 can be derived from the Gd_1_4Ag_5_1 structure type, the aristotype of this family. We give a detailed crystal structure description for Yb_1_1Hg_5_4 and discuss it in the context of the further known crystal structures closely related. A ranking within this structure family can be established by calculating features for the structural complexity for all structures, including the individual disorder phenomena.

  9. Diffraction-amalgamated grain boundary tracking for mapping 3D crystallographic orientation and strain fields during plastic deformation

    International Nuclear Information System (INIS)

    Toda, Hiroyuki; Kamiko, Takanobu; Tanabe, Yasuto; Kobayashi, Masakazu; Leclere, D.J.; Uesugi, Kentaro; Takeuchi, Akihisa; Hirayama, Kyosuke

    2016-01-01

    By amalgamating the X-ray diffraction technique with the grain boundary tracking technique, a novel method, diffraction-amalgamated grain boundary tracking (DAGT), has been developed. DAGT is a non-destructive in-situ analysis technique for characterising bulk materials, which can be applied up to near the point of fracture. It provides information about local crystal orientations and detailed grain morphologies in three dimensions, together with high-density strain mapping inside grains. As it obtains the grain morphologies by utilising X-ray imaging instead of X-ray diffraction, which latter is typically vulnerable to plastic deformation, DAGT is a fairly robust technique for analysing plastically deforming materials. Texture evolution and localised deformation behaviours have here been successfully characterised in Al–Cu alloys, during tensile deformation of 27% in applied strain. The characteristic rotation behaviours of grains were identified, and attributed to the effects of interaction with adjacent grains on the basis of the 3D local orientation and plastic strain distributions. It has also been revealed that 3D strain distribution in grains is highly heterogeneous, which is not explained by known mechanisms such as simple incompatibility with adjacent grains or strain percolation through soft grains. It has been clarified that groups consisting of a few adjacent grains may deform coordinately, especially in shear and lateral deformation, and the characteristic deformation pattern is thereby formed on a mesoscopic scale.

  10. The simplest representative of a complex series. The Hg-rich amalgam Yb{sub 11}Hg{sub 54}

    Energy Technology Data Exchange (ETDEWEB)

    Tambornino, Frank; Hoch, Constantin [LMU Muenchen (Germany). Dept. Chemie

    2017-09-01

    Yb{sub 11}Hg{sub 54} is a new member of a series of amalgams with composition close to MHg{sub 5}. Its crystal structure was solved and refined on the basis of single crystal data. The structure model was confirmed with a Rietveld refinement. Yb{sub 11}Hg{sub 54} has the first crystal structure in this family in which no disorder effects such as mixed occupation, split positions or superstructure formation is observed. It therefore can be regarded as a parent structure for all other amalgams. The crystal structure of Yb{sub 11}Hg{sub 54} can be derived from the Gd{sub 14}Ag{sub 51} structure type, the aristotype of this family. We give a detailed crystal structure description for Yb{sub 11}Hg{sub 54} and discuss it in the context of the further known crystal structures closely related. A ranking within this structure family can be established by calculating features for the structural complexity for all structures, including the individual disorder phenomena.

  11. Influence of the temperature, volume and type of solution in the mercury vaporization of dental amalgam residue

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Raquel dalla [Department of Chemical Engineering, State University of Maringa, Maringa - PR (Brazil)], E-mail: raqueldc_eng@yahoo.com.br; Cossich, Eneida Sala; Tavares, Celia Regina Granhen [Department of Chemical Engineering, State University of Maringa, Maringa - PR (Brazil)

    2008-12-15

    One of the qualitative methods for the identification of mercury vapor is what it occurs as a way of chemical reaction between palladium chloride and metallic mercury. Palladium chloride ribbons with yellowish coloration put in contact with the vaporized mercury of dental amalgam residue, liberates palladium and forms mercury chloride in your surface, and starts to have black coloration; this form identify the presence of the mercury vapor in the system. This work studies the influence of temperature, volume and type of barrier-solution in the vaporization of mercury during the period of storage of dental amalgam residues, aiming to establish the best conditions for storage of these residues. It was found that for all tested solutions, the longest storage times without any occurrence of mercury vaporization were obtained in the lowest temperatures tested and the largest solution volumes of barrier-solution. The radiographic effluent presented bigger efficacy in the reduction of the volatilization, increasing the period when the residue was stored, however the analysis of this solution after the vaporization test showed the presence of organic mercury. These results show that water is the most efficient barrier against the vaporization of mercury, since it did not result in organic mercury formation in the effluent solution from the storage process.

  12. Influence of the temperature, volume and type of solution in the mercury vaporization of dental amalgam residue

    International Nuclear Information System (INIS)

    Costa, Raquel dalla; Cossich, Eneida Sala; Tavares, Celia Regina Granhen

    2008-01-01

    One of the qualitative methods for the identification of mercury vapor is what it occurs as a way of chemical reaction between palladium chloride and metallic mercury. Palladium chloride ribbons with yellowish coloration put in contact with the vaporized mercury of dental amalgam residue, liberates palladium and forms mercury chloride in your surface, and starts to have black coloration; this form identify the presence of the mercury vapor in the system. This work studies the influence of temperature, volume and type of barrier-solution in the vaporization of mercury during the period of storage of dental amalgam residues, aiming to establish the best conditions for storage of these residues. It was found that for all tested solutions, the longest storage times without any occurrence of mercury vaporization were obtained in the lowest temperatures tested and the largest solution volumes of barrier-solution. The radiographic effluent presented bigger efficacy in the reduction of the volatilization, increasing the period when the residue was stored, however the analysis of this solution after the vaporization test showed the presence of organic mercury. These results show that water is the most efficient barrier against the vaporization of mercury, since it did not result in organic mercury formation in the effluent solution from the storage process

  13. Microhardness of bulk-fill composite materials

    OpenAIRE

    Kelić, Katarina; Matić, Sanja; Marović, Danijela; Klarić, Eva; Tarle, Zrinka

    2016-01-01

    The aim of the study was to determine microhardness of high- and low-viscosity bulk-fill composite resins and compare it with conventional composite materials. Four materials of high-viscosity were tested, including three bulk-fills: QuiXfi l (QF), x-tra fil (XTF) and Tetric EvoCeram Bulk Fill (TEBCF), while nanohybrid composite GrandioSO (GSO) served as control. The other four were low-viscosity composites, three bulk-fill materials: Smart Dentin Replacement (SDR), Venus Bulk Fill (VBF) and ...

  14. Review of fill mining technology in Canada

    Energy Technology Data Exchange (ETDEWEB)

    Singh, K. H.; Hedley, D. G.F.

    1980-05-15

    The Canadian mining industry has a long history of being in the fore-front in developing new technology in underground hardrock mines. Examples include the development of hydraulic and cemented fills, undercut-and-fill, mechanized cut-and-fill, post pillar, vertical retreat and blasthole mining methods. The evolution of this technology is briefly described in an historical review. Backfill serves many functions, although it is generally considered in terms of its support capabilities. These functions, mainly related to the mining method used, are evaluated in regard to regional support, pillar support, fill roof, working floor, dilution control and waste disposal. With the advent of blasthole and vertical retreat methods for pillar recovery operations, the freestanding height of backfill walls has assumed greater importance. Consequently, more attention is being given to what fill properties are required to achieve fill wall exposures up to 25 m wide by 90 m high. With the large increases in energy costs, alternatives to partially replace Portland cement in fill are being examined. The validation of mining concepts and the interaction of backfill is perhaps best evaluated by in-situ measurements. Examples are given of stress, deformation and fill pressure measurements in longitudinal cut-and-fill, post pillar mining and blasthole stoping with delayed fill which were taken in several mines in Canada. Finally, the overall design procedure used in deciding mining method, stope and pillar dimensions, sequence of extraction, fill properties and support systems at a new mine is described.

  15. LHC Abort Gap Filling by Proton Beam

    CERN Document Server

    Fartoukh, Stéphane David; Shaposhnikova, Elena

    2004-01-01

    Safe operation of the LHC beam dump relies on the possibility of firing the abort kicker at any moment during beam operation. One of the necessary conditions for this is that the number of particles in the abort gap should be below some critical level defined by quench limits. Various scenarios can lead to particles filling the abort gap. Time scales associated with these scenarios are estimated for injection energy and also coast where synchrotron radiation losses are not negligible for uncaptured particle motion. Two cases are considered, with RF on and RF off. The equilibrium distribution of lost particles in the abort gap defines the requirements for maximum tolerable relative loss rate and as a consequence the minimum acceptable longitudinal lifetime of the proton beam in collision.

  16. The clayey fissural fillings associated with N100º-110ºE fractures at the El Berrocal uranium mine (Sierra de Gredos, Spain: characterization, genesis and retention capacity of radioactive and other elements

    Directory of Open Access Journals (Sweden)

    Pérez del Villar, L.

    1993-08-01

    Full Text Available The clayey fissural fillings (18O data obtained from the quartz vein and the 2++ phosphate precipitation. The high organic C content in the clay fractions could be due to present biological activity in the clayey fissural filling or to organic acids transported from the topographic surface by the percolating water. In this last case, organie-clay complexes would probbly be formed.En relación con los procesos de migración/retención de los radionucleidos naturales en un medio granítico fisurado se han estudiado los rellenos fisurales arcillosos (18O obtenidos del cuarzo filoniano y de la fracción 2++. El alto contenido en C orgánico de la fracción arcilla de las muestras puede explicarse por la actividad bacteriana actual observada en los rellenos fisurales, o por la presencia de ácidos orgánicos, transportados por las aguas percolantes desde la superficie topográfica. En este último caso, han podido formarse complejos orgánico-arcillosos.

  17. Operation feedback of hydrogen filling station

    International Nuclear Information System (INIS)

    Pregassame, S.; Barral, K.; Allidieres, L.; Charbonneau, T.; Lacombe, Y.

    2004-01-01

    One of the technical challenges of hydrogen technology is the development of hydrogen infrastructures which satisfy either safety requirements and reliability of filling processes. AIR LIQUIDE realized an hydrogen filling station in Sassenage (France) operational since September 2003. This station is able to fill 3 buses a day up to 350bar by equilibrium with high pressure buffers. In parallel with commercial stations, the group wanted to create a testing ground in real conditions running with several objectives: validate on a full scale bench a simulation tool able to predict the temperature of both gas and cylinder's materials during filling processes; define the best filling procedures in order to reach mass, temperature and filling time targets; analyse the temperature distribution and evolution inside the cylinder; get a general knowledge about hydrogen stations from safety and reliability point of view; operate the first full scale refuelling station in France. The station is also up-graded for 700bar filling from either a liquid hydrogen source or a gas booster, with cold filling possibility. This paper presents the results concerning 350bar filling : thermal effects, optimal filling procedures and influence of parameters such as climatic conditions are discussed. (author)

  18. Understanding the safety and tolerability of facial filling therapeutics.

    Science.gov (United States)

    Kulichova, Daniela; Borovaya, Alyona; Ruzicka, Thomas; Thomas, Peter; Gauglitz, Gerd G

    2014-09-01

    Aesthetic medicine represents an emerging field for many specialties. Nowadays, a plethora of approaches are available to rejuvenate the human body and face, the latter being a frequent target for the placement of filling substances to correct wrinkles and volume loss. Nevertheless, based on the many products on the market, treating clinicians must pay specific attention to the properties of the respective materials, their associated side effects and any specific handling requirements to prevent potential short- and long-term adverse events. Types of filling materials, including biodegradable and non-biodegradable products, related complications, their conservative and invasive treatment options, as well as prevention strategies are described in this review. A profound knowledge of the facial anatomy as well as extensive experience with the various filling techniques and suitable materials for the respective areas remains crucial to prevent adverse events associated with filling procedures to the human face. Since side effects such as malar edema and foreign body granuloma do affect patients physically and psychologically to a significant extent and their successful treatment still remains challenging, further in depth studies on the tolerability of many filling materials utilized are required.

  19. Dielectric-filled radiofrequency linacs

    Energy Technology Data Exchange (ETDEWEB)

    Faehl, R J; Keinigs, R K; Pogue, E W [Los Alamos National Lab., NM (United States)

    1997-12-31

    High current, high brightness electron beam accelerators promise to open up dramatic new applications. Linear induction accelerators are currently viewed as the appropriate technology for these applications. A concept by Humphries and Hwang may permit radiofrequency accelerators to fulfill the same functions with greater simplicity and enhanced flexibility. This concept involves the replacement of vacuum rf cavities with dielectric filled ones. Simple analysis indicates that the resonant frequencies are reduced by a factor of ({epsilon}{sub 0}/{epsilon}){sup 1/2} while the stored energy is increased by {epsilon}/{epsilon}{sub 0}. For a high dielectric constant like water, this factor can approach 80. A series of numerical calculations of simple pill-box cavities was performed. Eigenfunctions and resonant frequencies for a full system configuration, including dielectric material, vacuum beamline, and a ceramic window separating the two have been computed. These calculations are compared with the results of a small experimental cavity which have been constructed and operated. Low power tests show excellent agreement. (author). 4 figs., 8 refs.

  20. An evaluation on microleakage and gap width of different dentin bonding agents in high copper amalgam restorations

    Directory of Open Access Journals (Sweden)

    Ghavam-Nasiri M. Associate Professor

    2003-07-01

    Full Text Available Statement of Problem: A lot of efforts have been made to create a complete adaptation between tooth"nand amalgam restorations."nPurpose: The aim of this study was to evaluate microleakage and interfacial micromorphology of"namalgam restorations lined with dentin adhesives, namely One Coat Bond, Syntac, Excite and Copalite,"nas liners."nMaterials and Methods: 144 intact human canine teeth were selected. Then class V cavities, with"nenamel and dentinal margins, were prepared on each of them. Cavities were lined with different dentin"nbonding systems (Syntac, One Coat Bond and Excite according to the manufacturer's instructions and"nrestored with Oralloy and Cinalloy, non gamma 2 spherical amalgams and Aristaloy a non gamma 2"nAdmixed alloy. Copalite was used in the group, served as controls. After thirty days storage in synthetic"nsaliva at 37°c, the specimens were thermocycled in saliva (4000 cycles. The degree of microleakage was"nassessed by means of basic fushin dye penetration and recorded. The gap width was evaluated with"nScanning Electron Microscope. Pearson and %2 tests were used to analyze the results."nResults: None of the systems, tested in this study, eliminated microleakage completely, Pearson's"ncorrelation coefficient showed a positive correlation between gap and microleakage (P<0/05.Statistical"nsignificant differences were revealed among the liners regarding gap and microleakage (P<0.05."nOne Coat Bond and Syntac appeared to leak less than other groups. The gap width by One Coat Bond"nand Syntac were respectively 0.35 and 0.3 urn in dentine, 0.2 and 0.1 in enamel. Excite and copalite gap"nwidth in dentine and enamel were 1,3-1.36 urn and 0.3-0.6, respectively. The type of amalgam did not"nhave any effect in the degree of microleakage and gap width (P>0/05."nConclusion: One Coat Bond and Syntac, comparing to Excite and Copalite, showed less microleakage"nand gap width.

  1. Iron filled carbon nanostructures from different precursors

    International Nuclear Information System (INIS)

    Costa, S.; Borowiak-Palen, E.; Bachmatiuk, A.; Ruemmeli, M.H.; Gemming, T.; Kalenczuk, R.J.

    2008-01-01

    Here, we present a study on the synthesis of different nanostructures with one single-step in situ filling (encapsulation) via carbon vapor deposition (CVD). Ferrocene, acetylferrocene and iron (II) nitrate as iron precursors were explored. The application of each of these compounds resulted in different carbon nanomaterials such as: iron filled multiwalled carbon nanotubes with a low filling ratio (Fe-MWCNT), iron filled nanocapsules and unfilled MWCNT. The as-produced samples were purified by high temperature annealing and acid treatment. The purified materials were characterised using transmission electron microscopy (TEM) and Raman spectroscopy

  2. Characterization of Low Density Glass Filled Epoxies

    National Research Council Canada - National Science Library

    Quesenberry, Matthew

    2003-01-01

    This report discusses the experimental determination and modeling of several thermophysical and mechanical properties of glass filled epoxy composite systems for potential use as electronic potting compounds...

  3. Performance of a gaseous detector based energy dispersive X-ray fluorescence imaging system: Analysis of human teeth treated with dental amalgam

    International Nuclear Information System (INIS)

    Silva, A.L.M.; Figueroa, R.; Jaramillo, A.; Carvalho, M.L.; Veloso, J.F.C.A.

    2013-01-01

    Energy dispersive X-ray fluorescence (EDXRF) imaging systems are of great interest in many applications of different areas, once they allow us to get images of the spatial elemental distribution in the samples. The detector system used in this study is based on a micro patterned gas detector, named Micro-Hole and Strip Plate. The full field of view system, with an active area of 28 × 28 mm 2 presents some important features for EDXRF imaging applications, such as a position resolution below 125 μm, an intrinsic energy resolution of about 14% full width at half maximum for 5.9 keV X-rays, and a counting rate capability of 0.5 MHz. In this work, analysis of human teeth treated by dental amalgam was performed by using the EDXRF imaging system mentioned above. The goal of the analysis is to evaluate the system capabilities in the biomedical field by measuring the drift of the major constituents of a dental amalgam, Zn and Hg, throughout the tooth structures. The elemental distribution pattern of these elements obtained during the analysis suggests diffusion of these elements from the amalgam to teeth tissues. - Highlights: • Demonstration of an EDXRF imaging system based on a 2D-MHSP detector for biological analysis • Evaluation of the drift of the dental amalgam constituents, throughout the teeth • Observation of Hg diffusion, due to hydroxyapatite crystal defects that compose the teeth tissues

  4. Performance of a gaseous detector based energy dispersive X-ray fluorescence imaging system: Analysis of human teeth treated with dental amalgam

    Energy Technology Data Exchange (ETDEWEB)

    Silva, A.L.M. [I3N, Physics Dept, University of Aveiro, 3810-193 Aveiro (Portugal); Figueroa, R.; Jaramillo, A. [Physics Department, Universidad de La Frontera, Temuco (Chile); Carvalho, M.L. [Atomic Physics Centre, University of Lisbon, 1649-03 Lisboa (Portugal); Veloso, J.F.C.A., E-mail: joao.veloso@ua.pt [I3N, Physics Dept, University of Aveiro, 3810-193 Aveiro (Portugal)

    2013-08-01

    Energy dispersive X-ray fluorescence (EDXRF) imaging systems are of great interest in many applications of different areas, once they allow us to get images of the spatial elemental distribution in the samples. The detector system used in this study is based on a micro patterned gas detector, named Micro-Hole and Strip Plate. The full field of view system, with an active area of 28 × 28 mm{sup 2} presents some important features for EDXRF imaging applications, such as a position resolution below 125 μm, an intrinsic energy resolution of about 14% full width at half maximum for 5.9 keV X-rays, and a counting rate capability of 0.5 MHz. In this work, analysis of human teeth treated by dental amalgam was performed by using the EDXRF imaging system mentioned above. The goal of the analysis is to evaluate the system capabilities in the biomedical field by measuring the drift of the major constituents of a dental amalgam, Zn and Hg, throughout the tooth structures. The elemental distribution pattern of these elements obtained during the analysis suggests diffusion of these elements from the amalgam to teeth tissues. - Highlights: • Demonstration of an EDXRF imaging system based on a 2D-MHSP detector for biological analysis • Evaluation of the drift of the dental amalgam constituents, throughout the teeth • Observation of Hg diffusion, due to hydroxyapatite crystal defects that compose the teeth tissues.

  5. Application of thin film mercury electrodes and solid amalgam electrodes in electrochemical analysis of the nucleic acids components: detection of the two-dimensional phase transients of adenosine

    Czech Academy of Sciences Publication Activity Database

    Hasoň, Stanislav; Vetterl, Vladimír

    2004-01-01

    Roč. 63, 1-2 (2004), s. 37-41 ISSN 1567-5394 R&D Projects: GA AV ČR KJB4004305; GA AV ČR IBS5004107 Institutional research plan: CEZ:AV0Z5004920 Keywords : mercury film electrodes * solid amalgam electrodes * roughness Subject RIV: BO - Biophysics Impact factor: 2.261, year: 2004

  6. The Gd{sub 14}Ag{sub 51} structure type and its relation to some complex amalgam structures

    Energy Technology Data Exchange (ETDEWEB)

    Tambornino, Frank; Sappl, Jonathan; Hoch, Constantin, E-mail: constantin.hoch@cup.uni-muenchen.de

    2015-01-05

    Highlights: • The Gd{sub 14}Ag{sub 51} structure type has been revisited on the basis of single crystal diffraction data. • Symmetry analysis from electron density and TEM shows the space group P6/m to be true. • Gd{sub 14}Ag{sub 51} shows good metallic behaviour. • Structure relations to alkali, alkaline-earth and rare-earth metal amalgams can be established. • Complexity values for the RE{sub 14}Ag{sub 51} structure family were calculated. - Abstract: A plethora of binary and ternary intermetallic compounds has been assigned to the Gd{sub 14}Ag{sub 51} structure type, crystallising in the hexagonal system (space group P6/m, a = 1264.30(18) pm, c = 933.58(11) pm for Gd{sub 14}Ag{sub 51}). Starting in the late 1960s, much work has been invested in the structural elucidation of these crystal structures. However, reliable single crystal data are scarce, and most structure type assignments have been performed merely on the basis of powder data. We have redetermined four representatives of the binary RE{sub 14}Ag{sub 51} structure type (RE = Y, Ce, Gd, Tb) with modern high-precision single crystal X-ray methods. The assignment of the Gd{sub 14}Ag{sub 51} structure type to space group P6/m was additionally verified by careful analysis of high resolution transmission electron micrographs. We emphasise the close relation of the Gd{sub 14}Ag{sub 51} structure type to the structures of some recently described amalgams of similar composition focussing on disorder phenomena and structural complexity. Furthermore, we provide detailed information on synthesis as well as electrical and magnetic properties for Gd{sub 14}Ag{sub 51}, the parent compound of this structure family.

  7. Adherence of Streptococcus Mutans to Microhybrid and Nanohybrid Resin Composites and Dental Amalgam: An In Vitro Study

    Directory of Open Access Journals (Sweden)

    Fariba Motevasselian

    2017-12-01

    Full Text Available Objectives: Streptococcus mutans (S. mutans is a cariogenic microorganism. The restorative materials which harbor a biofilm with high levels of S. mutans can accelerate the occurrence of dental caries. The purpose of this study was to evaluate the influence of different restorative materials on S. mutans colonization in a simple in-vitro biofilm formation model.Materials and Methods: Thirteen discs of each material (nanohybrid resin composite, microhybrid resin composite, and amalgam were prepared, polished, and sterilized in a gamma radiation chamber. The saliva-free specimens were exposed to the S. mutans bacterial suspension (0.5 McFarland and were incubated for 4 hours. Afterwards, the specimens were rinsed and sonicated in normal saline. 10µl of the obtained suspension was cultured in a sterile blood agar medium. After 24 hours, the number of colony forming units (CFU of S. mutans was counted. A sterility test control was considered for each group of materials. The data were analyzed by one-way ANOVA at 5% significance level.Results: The means and standard deviations of the logarithmic values of the colonies on the surfaces of amalgam, microhybrid, and nanohybrid resin composites were equal to 3.76±0.64, 3.91±0.52 and 3.34±0.74, respectively.Conclusions: There were no significant differences between the restorative materials in terms of S. mutans adhesion rate. The evaluated resin composites showed comparable numbers of CFUs, which could imply the importance of the polishing procedures.

  8. Provenance of detrital zircons from the Ribeira and Dom Feliciano Belts, comparison with African equivalents and implications on western Gondwana amalgamation. Geological Society of London-2008

    International Nuclear Information System (INIS)

    Basei, M.; Frimmel, H.E.; Nutman, A.P.; Preciozzi, F.

    2005-01-01

    The geologic make-up of southern Brazil has been defined by processes related to the Brasiliano orogenic cycle and, in particular, to con tractional tectonic events that led to the amalgamation of different terranes, which culminated in the formation of Western Gondwana (Campos Neto and Figueiredo, 1995; Brito Neves and Cordani,1991; Brito Neves et al, 1999, Campos Neto, 2000). Polycyclic deformation and metamorphism that masked the characteristics, including the age records, of the protoliths were associated with the juxtaposition of these different terranes. Ophiolitic remains and magmatic arc roots signal the existence of fossil subduction and collision zones, whereas intense post-tectonic to an orogenic granitic magmatism marks the end of the orogenic cycle towards the end of the Neoproterozoic Era. U-Pb dating of domains within single zircon grains has proven to be a very powerful tool for the unraveling of the complex tecto no-thermal evolution as well as in characterizing the provenance of the original sediments. This is due to the high resistance to weathering and to high closure temperatures with respect to the U-Pb isotope system in zircon. Over the past decade, the standard technique for this analytical approach has become the analyses of U-Pb isotope ratios by SHRIMP,preceded by cathodoluminescence analysis (McClaren et al 1994). In this study, a set of 11 new SHRIMP analyses on detrital zircon grains from the major metasedimentary units of the Ribeira and Dom Feliciano Belts of the southeastern portion of South America is presented and the data are compared with available analyses for the Gariep Belt (Basei et al. 2005) and a new analysis for the Damara Belt. Combined with available Sm-Nd bulk rock isotope data, the results will form the basis for a revised tectonic model for the formation of Western Gondwana

  9. Provenance of detrital zircons from the Ribeira and Dom Feliciano Belts, comparison with African equivalents and implications on Western Gondwana amalgamation

    International Nuclear Information System (INIS)

    Basei, M.; Frimmel, H.E.; Nutman, A.P.; Preciozzi, F.

    2008-01-01

    The geologic make-up of southern Brazil has been defined by processes related to the Brasiliano orogenic cycle and, in particular, to con tractional tectonic events that led to the amalgamation of different terranes, which culminated in the formation of Western Gondwana (Campos Neto and Figueiredo, 1995; Brito Neves and Cordani, 1991; Brito Neves et al, 1999, Campos Neto, 2000). Polycyclic deformation and metamorphism that masked the characteristics, including the age records, of the protoliths were associated with the juxtaposition of these different terranes. Ophiolitic remains and magmatic arc roots signal the existence of fossil subduction and collision zones, whereas intense post-tectonic to an orogenic granitic magmatism marks the end of the orogenic cycle towards the end of the Neoproterozoic Era. U-Pb dating of domains within single zircon grains has proven to be a very powerful tool for the unraveling of the complex tecto no-thermal evolution as well as in characterizing the provenance of the original sediments. This is due to the high resistance to weathering and to high closure temperatures with respect to the U-Pb isotope system in zircon. Over the past decade, the standard technique for this analytical approach has become the analyses of U-Pb isotope ratios by SHRIMP, preceded by cathodoluminescence analysis (McClaren et al 1994). In this study, a set of 11 new SHRIMP analyses on detrital zircon grains from the major metasedimentary units of the Ribeira and Dom Feliciano Belts of the southeastern portion of South America is presented and the data are compared with available analyses for the Gariep Belt (Basei et al. 2005) and a new analysis for the Damara Belt. Combined with available Sm-Nd bulk rock isotope data, the results will form the basis for a revised tectonic model for the formation of Western Gondwana

  10. Intravaginal administration of metformin hydrochloride loaded cationic niosomes amalgamated with thermosensitive gel for the treatment of polycystic ovary syndrome: In vitro and in vivo studies.

    Science.gov (United States)

    Saini, Neetu; Sodhi, Rupinder Kaur; Bajaj, Lotika; Pandey, Ravi Shankar; Jain, Upendra Kumar; Katare, Om Prakash; Madan, Jitender

    2016-08-01

    Metformin hydrochloride (MTF-HCl) is extensively recommended by physicians for the treatment of polycystic ovary syndrome (PCOS). Mechanistically, MTF-HCl activates AMP-dependent kinase-α (AMPK-α) pathway to decrease the glucose production, enhances fatty acid oxidation and elevates the uptake of glucose in tissues. However, despite favourable physicochemical properties, oral administration of MTF-HCl is associated with impaired bioavailability (50-60%), lactic-acidosis and frequent dosing (500mg 2-3 times a day) in PCOS that ultimately influence the patient compliance. Therefore, in present investigation, MTF-HCl loaded unmodified and cationic small unilamellar niosomes were separately amalgamated with thermosensitive gel (MTF-HCl-SUNs-Gel and MTF-HCl-C-SUNs-Gel) for the treatment of PCOS through vaginal route of administration. MTF-HCl-SUNs and MTF-HCl-C-SUNs were separately prepared by reverse phase evaporation method. The nanovesicle size and zeta-potential of MTF-HCl-C-SUNs were measured to be 210.3±14.8-nm (Ptreatment of PCOS rats under scheduled dose-dosage regimen with oral MTF-HCl solution, intravaginal MTF-HCl-SUNs-Gel and intravaginal MTF-HCl-C-SUNs-gel exhibited remarkable alterations, recruitment and development of normal follicles in addition to normalization of level of various hormones in PCOS. In conclusion, MTF-C-SUNs-Gel has paved the way for developing intravaginal dosage form of MTF-HCl for the treatment of PCOS. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Polyphase deformation history and strain analyses of the post-amalgamation depositional basins in the Arabian-Nubian Shield: Evidence from Fatima, Ablah and Hammamat Basins

    Science.gov (United States)

    Hamimi, Zakaria; El-Fakharani, Abdelhamid; Abdeen, Mamdouh M.

    2014-11-01

    Post-amalgamation depositional basins Asir tectonic terrane. The Hammamat PADB is investigated in Wadi Umm Gheig, Wadi Allaqi and Wadi Hodein in the Egyptian Eastern Desert tectonic terrane. It is supposed that the Fatima is a basin controlled by dextral transcurrent shearing occurred along the NE-oriented Wadi Fatima Shear Zone and the Ablah is a strike-slip pull-apart basin, and both basins were believed to be deposited during and soon after the Nabitah Orogeny (680-640 Ma) that marked suturing of the Afif terrane with the oceanic ANS terranes to the west. They were affected by at least three Neoproterozoic deformation phases and show geometric and kinematic relationships between folding and thrusting. The Hammamat PADB is a fault-bounded basin affected by a NW-SE- to NNW-SSE-oriented shortening phase just after the deposition of the molasse sediments, proved by NW- to NNW-verging folds and SE- to SSE-dipping thrusts that were refolded and thrusted in the same direction. The shortening phase in the Hammamat was followed by a transpressional wrenching phase related to the Najd Shear System, which resulted in the formation of NW-SE sinistral-slip faults associated with positive flower structures that comprise NE-verging folds and SW-dipping thrusts. Strain results in the three studied PADBs are nearly consistent, indicating that they are correlated and underwent the same history of deformation. The ANOVA test indicates that there is no significant difference for the Vector mean and ISYM for the three PADBs. There is only a significant difference for the Harmonic mean (P-value < 0.05). A Post Hoc test (Shefee) shows that the difference exists between the Allaqi and the Umm Gheig's deformed polymictic conglomeratic pebbles of the Hammamat PADB.

  12. 7 CFR 58.730 - Filling containers.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Filling containers. 58.730 Section 58.730 Agriculture... Procedures § 58.730 Filling containers. Hot fluid cheese from the cookers may be held in hotwells or hoppers... shall effectively measure the desired amount of product into the pouch or container in a sanitary manner...

  13. Selective filling of Photonic Crystal Fibres

    DEFF Research Database (Denmark)

    Nielsen, Kristian; Noordegraaf, Danny; Sørensen, Thorkild

    2005-01-01

    A model for calculating the time necessary for filling one or more specific holes in a photonic crystal fibre is made. This model is verified for water, and its enabling potential is illustrated by a polymer application. Selective filling of the core in an air-guide photonic crystal fibre...

  14. Raman spectra of filled carbon nanotubes

    International Nuclear Information System (INIS)

    Bose, S.M.; Behera, S.N.; Sarangi, S.N.; Entel, P.

    2004-01-01

    The Raman spectra of a metallic carbon nanotube filled with atoms or molecules have been investigated theoretically. It is found that there will be a three way splitting of the main Raman lines due to the interaction of the nanotube phonon with the collective excitations (plasmons) of the conduction electrons of the nanotube as well as its coupling with the phonon of the filling material. The positions and relative strengths of these Raman peaks depend on the strength of the electron-phonon interaction, phonon frequency of the filling atom and the strength of interaction of the nanotube phonon and the phonon of the filling atoms. Careful experimental studies of the Raman spectra of filled nanotubes should show these three peaks. It is also shown that in a semiconducting nanotube the Raman line will split into two and should be observed experimentally

  15. Text-Filled Stacked Area Graphs

    DEFF Research Database (Denmark)

    Kraus, Martin

    2011-01-01

    -filled stacked area graphs; i.e., graphs that feature stacked areas that are filled with small-typed text. Since these graphs allow for computing the text layout automatically, it is possible to include large amounts of textual detail with very little effort. We discuss the most important challenges and some...... solutions for the design of text-filled stacked area graphs with the help of an exemplary visualization of the genres, publication years, and titles of a database of several thousand PC games....

  16. Droplet Measurement below Single-Layer Grid Fill

    Directory of Open Access Journals (Sweden)

    Vitkovic Pavol

    2016-01-01

    Full Text Available The main part of the heat transfer in a cooling tower is in a fill zone. This one is consist of a cooling fill. For the cooling tower is used a film fill or grid fill or splash fill in the generally. The grid fill has lower heat transfer performance like film fill usually. But their advantage is high resistance to blockage of the fill. The grid fill is consisted with independent layers made from plastic usually. The layers consist of several bars connected to the different shapes. For experiment was used the rhombus shape. The drops diameter was measured above and below the Grid fill.

  17. PERVAPORATION USING ADSORBENT-FILLED MEMBRANES

    Science.gov (United States)

    Membranes containing selective fillers, such as zeolites and activated carbon, can improve the separation by pervaporation. Applications of adsorbent-filled membranes in pervaporation have been demonstrated by a number of studies. These applications include removal of organic co...

  18. Structural evolution of the Irtysh Shear Zone: implication for the Late Paleozoic amalgamation of multiple arc systems in Central Asia

    Science.gov (United States)

    Li, Pengfei; Sun, Min; Rosenbaum, Gideon

    2015-04-01

    The NW-SE Irtysh Shear Zone represents a major tectonic boundary in the Central Asian Orogenic Belt, recording the amalgamation history between the peri-Siberian orogenic system and the Kazakhstan orogenic system. The structural evolution and geodynamics of this shear zone is still poorly documented. Here we present new structural data complemented by chronological data in an attempt to unravel the geodynamic significance of the Irtysh Shear Zone in the context of accretion history of the Central Asian Orogenic Belt. Our results show three episodes of deformation for the shear zone. D1 foliation is locally recognized in low strain area and recorded by garnet inclusions, whereas D2 is represented by a sub-horizontal fabric and related NW-SE lineation. D3 is characterized by a transpersonal deformation event, to form a series of NW-SE mylonitic belts with sinistral kinematics, and to overprint D2 fabric forming regional-scale NW-SE upright folds. A paragneiss sample from the shear zone yielded the youngest detrital zircon peaks in the late Carboniferous, placing a maximum age constraint on the deformation, which overlaps in time with the late Paleozoic collision between the Chinese Altai and the intraoceanic arc system of the East Junggar and West Junggar. We interpret three episodes of deformation to represent orogenic thickening (D1), collapse (D2) and thickening (D3) in response to this collisional event. Sinistral shearing (D3) together with the coeval dextral shearing in the Tianshan accommodate eastward extrusion of the Kazakhstan orogenic system during the late Paleozoic amalgamation of the Central Asian Orogenic Belt. Acknowledgements: This study was financially supported by the Major Basic Research Project of the Ministry of Science and Technology of China (Grant: 2014CB440801), Hong Kong Research Grant Council (HKU705311P and HKU704712P), National Science Foundation of China (41273048, 41273012) and a HKU CRCG grant. The work is a contribution of the Joint

  19. Dural sinus filling defect: intrasigmoid encephalocele

    Science.gov (United States)

    Karatag, Ozan; Cosar, Murat; Kizildag, Betul; Sen, Halil Murat

    2013-01-01

    Filling defects of dural venous sinuses are considered to be a challenging problem especially in case of symptomatic patients. Many lesions have to be ruled out such as sinus thrombosis, arachnoid granulations and tumours. Encephalocele into dural sinus is also a rare cause of these filling defects of dural sinuses. Here, we report an extremely rare case with spontaneous occult invagination of temporal brain tissue into the left sigmoid sinus and accompanying cerebellar ectopia. PMID:24311424

  20. In vitro fabrication of dental filling nanopowder by green route and its antibacterial activity against dental pathogens.

    Science.gov (United States)

    Lee, Jeong-Ho; Velmurugan, Palanivel; Park, Jung-Hee; Lee, Kui-Jae; Jin, Jong-Sik; Park, Yool-Jin; Bang, Keuk-Soo; Oh, Byung-Taek

    2016-06-01

    The aim of this study was to introduce novel Sn, Cu, Hg, and Ag nanopowders (NPs) and a composite nanopowder (NP) synthesized using Salvia miltiorrhiza Bunge (SM) root extract as a reducing and capping agent to improve the antibacterial property of dental filling materials. All of the NPs obtained were characterized using a scanning transmission electron microscope (STEM), and energy dispersive X-ray (EDX) spectrum imaging was performed to map the elemental distributions of the NP composite. Fourier transform infrared (FTIR) spectroscopy was performed to identify the role of various functional groups in all of the obtained NPs and the phyto-compound responsible for the reduction of various metal ions. The X-ray diffraction (XRD) patterns clearly illustrated the crystalline phase of the synthesized NP. The antibacterial properties of the synthesized Sn, Cu, Hg, Ag, composite NP, SM root extract, and commercial amalgam powder were evaluated. The Cu, composite NP, SM root extract and Ag NP displayed excellent antibacterial activity against dental bacteria Streptococcus mutans and Lactobacillus acidophilus. The results of this study require further evaluation for signs of metal toxicity in appropriate animal models. However, the results are encouraging for the application of metal NPs as suitable alternatives for antibiotics and disinfectants, especially in dental filling materials. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Grain-filling duration and grain yield relationships in wheat mutants

    International Nuclear Information System (INIS)

    Larik, A.S.

    1987-01-01

    Nine stable mutants of bread wheat along with their mother cultivars were investigated for grain-filling characteristics in relation to grain yield. Significant differences among mutants for grain-filling duration and grain-filling index were observed. Inspite of the consistent differences in grain-filling duration there was no significant association between grain-filling duration and grain yield in C-591 and Nayab mutants. Failure to detect an yield advantage due to differences in grain-filling duration in these genotypes suggests that any advantage derived from alteration of grain-filling period may have been outweighed by the coincident changes in length of the vegetative period. Other factors such as synchrony of anthesis may have limited out ability to find an association between grainfilling duration and grain yield. On the contrary, significant association between grain-filling duration and grain yield displayed by indus-66 indus-66 mutants derived from gamma rays, shows the ability of gamma rays to induce functional alternations in the pattern of gene arrangements controlling these traits. Thus, the vaability observed in these physiological traits suggests that selection for these traits could be useful in improving grain yield. (author)

  2. Stoichiometric and X-ray diffraction analysis on the γ2→eta' transformation in a dispersant phase silver amalgam

    International Nuclear Information System (INIS)

    Jensen, S.J.; Joergensen, K.D.

    1981-01-01

    Phase composition of an amalgam prepared from a two-particle alloy was determined over a 2-year period by X-ray diffraction. The γ 2 -content decreased from 3.6% to 0.3%, and eta' increased from 3.9% to 10.0%. These alterations in phase content agreed with stoichiometric calculations performed on the basis of the solid state reaction: γ 2 +Ag/Cu→eta'+γ 1 . (author)

  3. Target-induced formation of gold amalgamation on DNA-based sensing platform for electrochemical monitoring of mercury ion coupling with cycling signal amplification strategy

    International Nuclear Information System (INIS)

    Chen, Jinfeng; Tang, Juan; Zhou, Jun; Zhang, Lan; Chen, Guonan; Tang, Dianping

    2014-01-01

    Graphical abstract: -- Highlights: •We report a new electrochemical sensing protocol for the detection of mercury ion. •Gold amalgamation on DNA-based sensing platform was used as nanocatalyst. •The signal was amplified by cycling signal amplification strategy. -- Abstract: Heavy metal ion pollution poses severe risks in human health and environmental pollutant, because of the likelihood of bioaccumulation and toxicity. Driven by the requirement to monitor trace-level mercury ion (Hg 2+ ), herein we construct a new DNA-based sensor for sensitive electrochemical monitoring of Hg 2+ by coupling target-induced formation of gold amalgamation on DNA-based sensing platform with gold amalgamation-catalyzed cycling signal amplification strategy. The sensor was simply prepared by covalent conjugation of aminated poly-T (25) oligonucleotide onto the glassy carbon electrode by typical carbodiimide coupling. Upon introduction of target analyte, Hg 2+ ion was intercalated into the DNA polyion complex membrane based on T–Hg 2+ –T coordination chemistry. The chelated Hg 2+ ion could induce the formation of gold amalgamation, which could catalyze the p-nitrophenol with the aid of NaBH 4 and Ru(NH 3 ) 6 3+ for cycling signal amplification. Experimental results indicated that the electronic signal of our system increased with the increasing Hg 2+ level in the sample, and has a detection limit of 0.02 nM with a dynamic range of up to 1000 nM Hg 2+ . The strategy afforded exquisite selectivity for Hg 2+ against other environmentally related metal ions. In addition, the methodology was evaluated for the analysis of Hg 2+ in spiked tap-water samples, and the recovery was 87.9–113.8%

  4. Pollution status and mercury sedimentation in small river near amalgamation and cyanidation units of Talawaan-Tatelu gold mining, North Sulawesi

    Directory of Open Access Journals (Sweden)

    T M Palapa

    2015-04-01

    Full Text Available Information Journal Help User Username Password Remember me Notifications View Subscribe / Unsubscribe Search Keyword : The activities of traditional gold mining in the region of Talawaan-Tatelu, North Minahasa regency, North Sulawesi, have been ongoing since 1998. Processing the gold in the mine consists of three stages i.e., the excavation, milling and amalgamation, and the use of cyanide tanks. Waste from the processing units which contains high mercury, generally flows directly into small rivers nearby. This study aimed to determine the pollution status and mercury sedimentation in a small river near the amalgamation and cyanidation processing units in Talawaan-Tatelu gold mining. Water and sediment samples were taken from seven stations along a small river, as many as four temporal replications (weekly. Mercury determination in water and sediments was done by using Cold Vapor Atomic Fluorescence Spectrometry. Pollution status was determined through the calculation of Hg ratio in water samples and in water quality criterion (4th class, as noted in The Indonesian Government Regulation No. 82 of 2001 on Water Quality and Water Pollution Control, while the mercury sedimentation was calculated from the ratio of mercury in water and sediment. The results showed that there are differences in the status of pollution and mercury sedimentation of seven sampling stations. Amalgamation and cyanidation processing units provide significant impact on the status of pollution (although it is categorized in contamination and mercury sedimentation along small river in the gold mining area of Talawaan-Tatelu. The downstream of this small river, Talawaan River, is the main river of the Talawaan watershed. Things that should be a concern are Talawaan rural communities living near Talawaan River who often use the water for daily needs such as bathing and washing. Risk to public health around the river can arise when the status of pollution and mercury

  5. Target-induced formation of gold amalgamation on DNA-based sensing platform for electrochemical monitoring of mercury ion coupling with cycling signal amplification strategy

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Jinfeng; Tang, Juan; Zhou, Jun; Zhang, Lan; Chen, Guonan; Tang, Dianping, E-mail: dianping.tang@fzu.edu.cn

    2014-01-31

    Graphical abstract: -- Highlights: •We report a new electrochemical sensing protocol for the detection of mercury ion. •Gold amalgamation on DNA-based sensing platform was used as nanocatalyst. •The signal was amplified by cycling signal amplification strategy. -- Abstract: Heavy metal ion pollution poses severe risks in human health and environmental pollutant, because of the likelihood of bioaccumulation and toxicity. Driven by the requirement to monitor trace-level mercury ion (Hg{sup 2+}), herein we construct a new DNA-based sensor for sensitive electrochemical monitoring of Hg{sup 2+} by coupling target-induced formation of gold amalgamation on DNA-based sensing platform with gold amalgamation-catalyzed cycling signal amplification strategy. The sensor was simply prepared by covalent conjugation of aminated poly-T{sub (25)} oligonucleotide onto the glassy carbon electrode by typical carbodiimide coupling. Upon introduction of target analyte, Hg{sup 2+} ion was intercalated into the DNA polyion complex membrane based on T–Hg{sup 2+}–T coordination chemistry. The chelated Hg{sup 2+} ion could induce the formation of gold amalgamation, which could catalyze the p-nitrophenol with the aid of NaBH{sub 4} and Ru(NH{sub 3}){sub 6}{sup 3+} for cycling signal amplification. Experimental results indicated that the electronic signal of our system increased with the increasing Hg{sup 2+} level in the sample, and has a detection limit of 0.02 nM with a dynamic range of up to 1000 nM Hg{sup 2+}. The strategy afforded exquisite selectivity for Hg{sup 2+} against other environmentally related metal ions. In addition, the methodology was evaluated for the analysis of Hg{sup 2+} in spiked tap-water samples, and the recovery was 87.9–113.8%.

  6. Electrochemical generation of arsenic volatile species using a gold/mercury amalgam cathode. Determination of arsenic by atomic absorption spectrometry

    Directory of Open Access Journals (Sweden)

    Andrea Caiminagua

    2015-03-01

    Full Text Available The electrochemical generation of arsenic volatile species (arsine using an Au/Hg amalgam cathode in a 0.5 M H2SO4 solution, is described. Results were compared with those obtained with other cathodes commonly used for generation of arsine. The effects of the electrolytic conditions and interferent ions have been studied. Results show that the Au/Hg cathode has better tolerance to interference and higher repeatability than cathodes made out of platinum (Pt, gold (Au, reticulated glassy carbon (RGC, lead (Pb. Under optimized conditions, a 0.027 μg L−1 (3σ detection limit for As(III in aqueous solutions and a 2.4% relative standard deviation for a 0.1 μg L−1 As(III were obtained. The accuracy of the method was verified by determination of As in a certified reference material. The proposed method was applied to the determination of As in spiked tap water samples.

  7. Fast and sensitive metronidazole determination by means of voltammetry on renewable amalgam silver based electrode without the preconcentration step

    Directory of Open Access Journals (Sweden)

    Piech Robert

    2017-01-01

    Full Text Available Application of cyclic renewable amalgam silver-based electrode (Hg(AgFE for sensitive metronidazole detection by the differential pulse voltammetry (DPV is described. The unique properties of the Hg(AgFE such as the relative large surface area and its fast and very simple renewal were fully utilized for sensitive measurements. Compared with the classical hanging mercury drop electrode (HMDE, the renewable Hg(AgFE significantly increases the reduction peak current of metronidazole because of its large surface area. The effects of various factors for the metronidazole determination such as: pulse height and width, step potential, surface area of the working electrode, and basic electrolyte composition are optimized. The obtained calibration graph is linear from 0.1 (17 μg L-1 to 2 μM (342 μg L-1 with correlation coefficient 0.999. For the Hg(AgFE with the surface area of 10.1 mm2 the limit of detection (LOD is 20 nM (3.4 μg L-1. The repeatability of the method at a concentration of the analyte of 0.5 μM (5.6 μg L−1, expressed as relative standard deviation (RSD is 2.1 % (n = 7. The proposed method was successfully applied and confirmed by studying recovery of metronidazole from spiked samples.

  8. Amalgamation based optical and colorimetric sensing of mercury(II) ions with silver graphene oxide nanocomposite materials

    International Nuclear Information System (INIS)

    Kamali, Khosro Zangeneh; Pandikumar, Alagarsamy; Jayabal, Subramaniam; Huang, Nay Ming; Ramaraj, Ramasamy; Lim, Hong Ngee; Ong, Boon Hoong; Bien, Chia Sheng Daniel; Kee, Yeh Yee

    2016-01-01

    The article describes a facile method for the preparation of a conjugate composed of silver nanoparticles and graphene oxide (Ag GO) via chemical reduction of silver precursors in the presence of graphene oxide (GO) while sonicating the solution. The Ag GO was characterized by X-ray photoelectron spectroscopy, X-ray powder diffraction, and energy-dispersive X-ray spectroscopy. The nanocomposite undergoes a color change from yellow to colorless in presence of Hg(II), and this effect is based on the disappearance of the localized surface plasmon resonance absorption of the AgNPs due to the formation of silver-mercury amalgam. The presence of GO, on the other hand, prevents the agglomeration of the AgNPs and enhances the stability of the nanocomposite material in solution. Hence, the probe represents a viable optical probe for the determination of mercury(II) ions in that it can be used to visually detect Hg(II) concentrations as low as 100 μM. The instrumental LOD is 338 nM. (author)

  9. The Amalgamation of SVR and ANFIS Models with Synchronized Phasor Measurements for On-Line Voltage Stability Assessment

    Directory of Open Access Journals (Sweden)

    Mohammed Amroune

    2017-10-01

    Full Text Available This paper presents the application of support vector regression (SVR and adaptive neuro-fuzzy inference system (ANFIS models that are amalgamated with synchronized phasor measurements for on-line voltage stability assessment. As the performance of SVR model extremely depends on the good selection of its parameters, the recently developed ant lion optimizer (ALO is adapted to seek for the SVR’s optimal parameters. In particular, the input vector of ALO-SVR and ANFIS soft computing models is provided in the form of voltage magnitudes provided by the phasor measurement units (PMUs. In order to investigate the effectiveness of ALO-SVR and ANFIS models towards performing the on-line voltage stability assessment, in-depth analyses on the results have been carried out on the IEEE 30-bus and IEEE 118-bus test systems considering different topologies and operating conditions. Two statistical performance criteria of root mean square error (RMSE and correlation coefficient (R were considered as metrics to further assess both of the modeling performances in contrast with the power flow equations. The results have demonstrated that the ALO-SVR model is able to predict the voltage stability margin with greater accuracy compared to the ANFIS model.

  10. Performance of a gaseous detector based energy dispersive X-ray fluorescence imaging system: Analysis of human teeth treated with dental amalgam

    Science.gov (United States)

    Silva, A. L. M.; Figueroa, R.; Jaramillo, A.; Carvalho, M. L.; Veloso, J. F. C. A.

    2013-08-01

    Energy dispersive X-ray fluorescence (EDXRF) imaging systems are of great interest in many applications of different areas, once they allow us to get images of the spatial elemental distribution in the samples. The detector system used in this study is based on a micro patterned gas detector, named Micro-Hole and Strip Plate. The full field of view system, with an active area of 28 × 28 mm2 presents some important features for EDXRF imaging applications, such as a position resolution below 125 μm, an intrinsic energy resolution of about 14% full width at half maximum for 5.9 keV X-rays, and a counting rate capability of 0.5 MHz. In this work, analysis of human teeth treated by dental amalgam was performed by using the EDXRF imaging system mentioned above. The goal of the analysis is to evaluate the system capabilities in the biomedical field by measuring the drift of the major constituents of a dental amalgam, Zn and Hg, throughout the tooth structures. The elemental distribution pattern of these elements obtained during the analysis suggests diffusion of these elements from the amalgam to teeth tissues.

  11. Assessment of periapical health, quality of root canal filling, and ...

    African Journals Online (AJOL)

    Sixty three teeth were found to have short root canal fillings, whereas 74 teeth had adequate root canal fillings, and the remaining 10 teeth had over extended root canal filling. A significant correlation was observed between the length of root filling and apical periodontitis (P = 0,023). Inadequately dense root canal filling was ...

  12. Flexible walled container having membrane fitment for use with aseptic filling apparatus

    International Nuclear Information System (INIS)

    Davis, J.C.; Reiss, R.J.; Rica, A.F.

    1984-01-01

    There is disclosed an aseptic flexible walled container having a rigid fitment member cooperative with an aseptic filling apparatus and including a neck, outer flanges surrounding the neck, a frangible membrane and an outer end rim receptive of an hermetically sealed lid. The neck is formed with an internal chamferred seating shoulder for fluid-tight engagement with a fill tube. One outer flange cooperates with clamping jaws of the aseptic filling apparatus for detachably sealing the fitment to a sterilizing chamber and placing it in position for insertion of the filling tube which ruptures the membrane and permits the aseptic introduction of product to the container's interior. The other outer flange is secured to an opening in a wall of the flexible container. The joined fitment and container are presterilized prior to filling. Selected materials for the multi-ply container walls and the fitment permit the container to withstand gamma ray and other sterilization treatment, heat and pressure while maintaining required strength. After the container is aseptically filled, such as with flowable food product, the fill tube is withdrawn and a lid is hermetically sealed onto the rim of the fitment. A heat shield adjacent a container wall surrounds the fitment to protect the container from excessive heat generated by the associated filling apparatus during filling

  13. Computed tomography assessment of the efficiency of different techniques for removal of root canal filling material

    International Nuclear Information System (INIS)

    Dall'agnol, Cristina; Barletta, Fernando Branco; Hartmann, Mateus Silveira Martins

    2008-01-01

    This study evaluated the efficiency of different techniques for removal of filling material from root canals, using computed tomography (CT). Sixty mesial roots from extracted human mandibular molars were used. Root canals were filled and, after 6 months, the teeth were randomly assigned to 3 groups, according to the root-filling removal technique: Group A - hand instrumentation with K-type files; Group B - reciprocating instrumentation with engine-driven K-type files; and Group C rotary instrumentation with engine-driven ProTaper system. CT scans were used to assess the volume of filling material inside the root canals before and after the removal procedure. In both moments, the area of filling material was outlined by an experienced radiologist and the volume of filling material was automatically calculated by the CT software program. Based on the volume of initial and residual filling material of each specimen, the percentage of filling material removed from the root canals by the different techniques was calculated. Data were analyzed statistically by ANOVA and chi-square test for linear trend (α=0.05). No statistically significant difference (p=0.36) was found among the groups regarding the percent means of removed filling material. The analysis of the association between the percentage of filling material removal (high or low) and the proposed techniques by chi-square test showed statistically significant difference (p=0.015), as most cases in group B (reciprocating technique) presented less than 50% of filling material removed (low percent removal). In conclusion, none of the techniques evaluated in this study was effective in providing complete removal of filling material from the root canals. (author)

  14. Computed tomography assessment of the efficiency of different techniques for removal of root canal filling material

    Energy Technology Data Exchange (ETDEWEB)

    Dall' agnol, Cristina; Barletta, Fernando Branco [Lutheran University of Brazil, Canoas, RS (Brazil). Dental School. Dept. of Dentistry and Endodontics]. E-mail: fbarletta@terra.com.br; Hartmann, Mateus Silveira Martins [Uninga Dental School, Passo Fundo, RS (Brazil). Postgraduate Program in Dentistry

    2008-07-01

    This study evaluated the efficiency of different techniques for removal of filling material from root canals, using computed tomography (CT). Sixty mesial roots from extracted human mandibular molars were used. Root canals were filled and, after 6 months, the teeth were randomly assigned to 3 groups, according to the root-filling removal technique: Group A - hand instrumentation with K-type files; Group B - reciprocating instrumentation with engine-driven K-type files; and Group C rotary instrumentation with engine-driven ProTaper system. CT scans were used to assess the volume of filling material inside the root canals before and after the removal procedure. In both moments, the area of filling material was outlined by an experienced radiologist and the volume of filling material was automatically calculated by the CT software program. Based on the volume of initial and residual filling material of each specimen, the percentage of filling material removed from the root canals by the different techniques was calculated. Data were analyzed statistically by ANOVA and chi-square test for linear trend ({alpha}=0.05). No statistically significant difference (p=0.36) was found among the groups regarding the percent means of removed filling material. The analysis of the association between the percentage of filling material removal (high or low) and the proposed techniques by chi-square test showed statistically significant difference (p=0.015), as most cases in group B (reciprocating technique) presented less than 50% of filling material removed (low percent removal). In conclusion, none of the techniques evaluated in this study was effective in providing complete removal of filling material from the root canals. (author)

  15. Topological materials discovery using electron filling constraints

    Science.gov (United States)

    Chen, Ru; Po, Hoi Chun; Neaton, Jeffrey B.; Vishwanath, Ashvin

    2018-01-01

    Nodal semimetals are classes of topological materials that have nodal-point or nodal-line Fermi surfaces, which give them novel transport and topological properties. Despite being highly sought after, there are currently very few experimental realizations, and identifying new materials candidates has mainly relied on exhaustive database searches. Here we show how recent studies on the interplay between electron filling and nonsymmorphic space-group symmetries can guide the search for filling-enforced nodal semimetals. We recast the previously derived constraints on the allowed band-insulator fillings in any space group into a new form, which enables effective screening of materials candidates based solely on their space group, electron count in the formula unit, and multiplicity of the formula unit. This criterion greatly reduces the computation load for discovering topological materials in a database of previously synthesized compounds. As a demonstration, we focus on a few selected nonsymmorphic space groups which are predicted to host filling-enforced Dirac semimetals. Of the more than 30,000 entires listed, our filling criterion alone eliminates 96% of the entries before they are passed on for further analysis. We discover a handful of candidates from this guided search; among them, the monoclinic crystal Ca2Pt2Ga is particularly promising.

  16. NSLS-II filling pattern measurement

    International Nuclear Information System (INIS)

    Yong Hu; Dalesio, L.B.; Kiman Ha; Pinayev, I.

    2012-01-01

    Multi-bunch injection will be deployed at NSLS-II. High bandwidth diagnostic beam monitors with high speed digitizers are used to measure bunch-by-bunch charge variation. In order to minimize intensity-correlated orbit oscillations due to uneven bunch patterns, we need to measure the filling pattern (also named bunch pattern or bunch structure). This paper focuses on filling pattern measurements: how to measure bunch structure and make this information available in EPICS-based control system. This measurement requires combination of 3 types of beam monitors (Wall Current Monitor, Fast Current Transformer and Beam Position Monitor), data acquisition and controls (fast digitizer, EPICS software, etc.) and Event Timing system. High-bandwidth filling pattern monitor requires high-speed digitizer to sample its analog output signal. The evaluation results of commercial fast digitizer Agilent Acqiris and high bandwidth detector Bergoz FCT are presented. We have also tested the algorithm software for filling pattern measurement as well as the interface to event timing system. It appears that filling pattern measurement system is well understood and the tests for control hardware and software have given good results

  17. Improving the support characteristics of hydraulic fill

    Energy Technology Data Exchange (ETDEWEB)

    Corson, D. R.; Dorman, K. R.; Sprute, R. H.

    1980-05-15

    Extensive laboratory and field testing has defined the physical properties of hydraulic fill. Effect of void ratio on percolation rate has been quantified, and tests were developed to estimate waterflow through fill material in a given state underground. Beneficial effect on fill's support capability through addition of cement alone or in conjunction with vibratory compaction has been investigated. Two separate field studies in operating cut-and-fill mines measured vein-wall deformation and loads imposed on backfilled stopes. Technology has been developed that will effectively and efficiently dewater and densify ultra-fine-grained slurries typical of metal mine hydraulic backfill. At least two operators are using this electrokinetic technique to dewater slimes collected in underground sumps or impoundments. This technique opens up the possibility of using the total unclassified tailings product as a hydraulic backfill. Theoretical enhancement of ground support and rock-burst control through improved support capability will be tested in a full-scale mine stope installation. Both a horizontal layer and a vertical column of high modulus fill will be placed in an attempt to reduce stope wall closure, support more ground pressure, and lessen rock-burst occurrence.

  18. Primary Sjögren’s syndrome with polymyositis, a rare amalgamation

    Directory of Open Access Journals (Sweden)

    Harpreet Singh

    2018-01-01

    Full Text Available Sjögren’s syndrome is characterized by diminished lacrimal and salivary gland secretory function. This disorder is not strictly confined to the exocrine glands and its manifestations may extend to extraglandular sites, such as the lungs, kidneys, reticuloendothelial system, and the musculoskeletal system. Although muscular manifestations are very common with Sjögren’s syndrome, true myopathy is very rare. Here, we report a case of a 45-year-old woman who presented with complaints of bilateral progressive weakness of upper and lower limbs associated with difficulty in neck holding with a history of dryness of the mouth and the eyes. The diagnosis of polymyositis associated with Sjögren’s syndrome was established on the basis of clinical picture and diagnostic tests. True polymyositis is very rare in primary Sjögren syndrome and there are scarcely any cases of primary Sjögren’s syndrome with polymyositis reported in the literature.

  19. Fort George G. Meade Active Sanitary Landfill and Clean Fill Dump, Remedial Investigation Report

    National Research Council Canada - National Science Library

    1992-01-01

    ...) and a Site Inspection at the inactive Clean Fill Dump (CFD) sites. The objective of the ASL study involved obtaining additional data to evaluate the potential environmental impacts associated with the landfill operations...

  20. Fissure fillings from Finnsjoen and Studsvik Sweden

    International Nuclear Information System (INIS)

    Tullborg, E.-L.; Larsson, S.Aa.

    1982-12-01

    Samples were taken from cores and collected at different levels. The bedrock at Finnsjoen is a Svecokarelian granite-granodiorite, the most frequent mineral in the fissures being calcite. The water from boreholes have a mean S 18 O value of -12 per thousand and saturated by calcite. Isotopically three different groups of calcite have been distinguished. Ages of 29+-13x10 3 years to 79+-25x10 3 years were estimated. Two generations of quartz were recognized the minerals prehnite and lanmontite were found Most fissure filling materials have cation exchange capacities. The bedrock at Studsvik is a Svecokarelian gneiss of sedimentary type which is migmatized with calcite and chlorite as fissure filling minerals. Most fissure fillings are thin and simple Claby minerals of smectite type are also frequent. (G.B.)

  1. One-dimensional Gromov minimal filling problem

    International Nuclear Information System (INIS)

    Ivanov, Alexandr O; Tuzhilin, Alexey A

    2012-01-01

    The paper is devoted to a new branch in the theory of one-dimensional variational problems with branching extremals, the investigation of one-dimensional minimal fillings introduced by the authors. On the one hand, this problem is a one-dimensional version of a generalization of Gromov's minimal fillings problem to the case of stratified manifolds. On the other hand, this problem is interesting in itself and also can be considered as a generalization of another classical problem, the Steiner problem on the construction of a shortest network connecting a given set of terminals. Besides the statement of the problem, we discuss several properties of the minimal fillings and state several conjectures. Bibliography: 38 titles.

  2. Posterior bulk-filled resin composite restorations.

    DEFF Research Database (Denmark)

    van Dijken, Jan WV; Pallesen, Ulla

    2016-01-01

    up to 4mm as needed to fill the cavity 2mm short of the occlusal cavosurface. The occlusal part was completed with the nano-hybrid resin composite (Ceram X mono+). In the other cavity, the resin composite-only (Ceram X mono+) was placed in 2mm increments. The restorations were evaluated using...... Class II, 4 SDR-CeramX mono+ and 6 CeramXmono+-only restorations. The main reasons for failurewere tooth fracture (6) and secondary caries (4). The annual failure rate (AFR) for all restorations (Class I and II) was for the bulk-filled-1.1% and for the resin composite-only restorations 1...

  3. Alkaline earth filled nickel skutterudite antimonide thermoelectrics

    Science.gov (United States)

    Singh, David Joseph

    2013-07-16

    A thermoelectric material including a body centered cubic filled skutterudite having the formula A.sub.xFe.sub.yNi.sub.zSb.sub.12, where A is an alkaline earth element, x is no more than approximately 1.0, and the sum of y and z is approximately equal to 4.0. The alkaline earth element includes guest atoms selected from the group consisting of Be, Mb, Ca, Sr, Ba, Ra and combinations thereof. The filled skutterudite is shown to have properties suitable for a wide variety of thermoelectric applications.

  4. Creep of granulated loose-fill insulation

    DEFF Research Database (Denmark)

    Rasmussen, Torben Valdbjørn

    This report presents a proposal for a standardised method for creep tests and the necessary theoretical framework that can be used to describe creep of a granulated loose-fill material. Furthermore results from a round robin test are shown. The round robin test was carried out in collaboration...... with SP-Building Physics in Sweden and VTT Building Technology in Finland. For the round robin test a cellulosic fibre insulation material was used. The proposed standardised method for creep tests and theories are limited to cases when the granulated loose-fill material is exposed to a constant...

  5. Did the amalgamation of continents drive the end Ordovician mass extinctions?

    DEFF Research Database (Denmark)

    Mac Ørum Rasmussen, Christian; Harper, David Alexander Taylor

    2011-01-01

    not uniformly distributed, nor was the succeeding recovery. Here we argue that changing plate tectonic configurations during the Ordovician–Silurian interval may have exerted a primary control on biotic extinction and recovery. In particular the proximity and ultimate loss of microcontinents and associated...... smaller terranes around Laurentia may have restricted shelf and slope habitats during the latest Ordovician but, nevertheless, in a contracted Iapetus Ocean, provided migration routes to help drive a diachronous early Silurian recovery. The conclusion that plate tectonics was a primary factor controlling...

  6. The structure of filled skutterudites and the local vibration behavior of the filling atom

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Xiaojuan [Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China); Dongguan Institute of Neutron Science, Dongguan 523808 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Zong, Peng-an [State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China); Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050 (China); Chen, Xihong [Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050 (China); Tao, Juzhou, E-mail: taoj@ihep.ac.cn [Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China); Dongguan Institute of Neutron Science, Dongguan 523808 (China); Lin, He, E-mail: linhe@sinap.ac.cn [Shanghai Institute of Applied Physics, Chinese Academy of Science, Shanghai 201204 (China)

    2017-02-15

    Both of atomic pair distribution function (PDF) and extended x-ray absorption fine structure (EXAFS) experiments have been carried out on unfilled and Yb-filled skutterudites Yb{sub x}Co{sub 4}Sb{sub 12} (x=0, 0.15, 0.2 and 0.25) samples. The structure refinements on PDF data confirm the large amplitude vibration of Yb atom and the dependence of Yb vibration amplitude on the filling content. Temperature dependent EXAFS experiment on filled skutterudites have been carried out at Yb L{sub Ⅲ}-edge in order to explore the local vibration behavior of filled atom. EXAFS experiments show that the Einstein temperature of the filled atom is very low (70.9 K) which agrees with the rattling behavior.

  7. Cytotoxicity of dental composite (co)monomers and the amalgam component Hg{sup 2+} in human gingival fibroblasts

    Energy Technology Data Exchange (ETDEWEB)

    Reichl, Franz-Xaver; Simon, Sabine; Esters, Magalie; Seiss, Mario [Ludwig-Maximilians-University of Munich, Walther-Straub-Institute of Pharmacology and Toxicology, Munich (Germany); Kehe, Kai [Bundeswehr Institute of Pharmacology and Toxicology, Munich (Germany); Kleinsasser, Norbert [University of Regensburg, Department of Otolaryngology - Head and Neck Surgery, Regensburg (Germany); Hickel, Reinhard [Ludwig-Maximilians-University, Department of Operative Dentistry and Periodontology, Munich (Germany)

    2006-08-15

    Unpolymerized resin (co)monomers or mercury (Hg) can be released from restorative dental materials (e.g. composites and amalgam). They can diffuse into the tooth pulp or the gingiva. They can also reach the gingiva and organs by the circulating blood after the uptake from swallowed saliva. The cytotoxicity of dental composite components hydroxyethylmethacrylate (HEMA), triethyleneglycoldimethacrylate (TEGDMA), urethanedimethacrylate (UDMA), and bisglycidylmethacrylate (Bis-GMA) as well as the amalgam component Hg{sup 2+} (as HgCl{sub 2}) and methyl mercury chloride (MeHgCl) was investigated on human gingival fibroblasts (HGFs) at two time intervals. To test the cytotoxicity of substances, the bromodeoxyuridine (BrdU) assay and the lactate dehydrogenase (LDH) assay were used. The test substances were added in various concentrations and cells were incubated for 24 or 48 h. The EC{sub 50} values were obtained as half-maximum-effect concentrations from fitted curves. Following EC{sub 50} values were found [BrdU: mean (mmol/l); SEM in parentheses; n=12]: (24 h/48 h) HEMA 8.860 (0.440)/6.600(0.630), TEGDMA 1.810(0.130)/1.220(0.130), UDMA 0.120(0.010)/0.140(0.010), BisGMA 0.060(0.004)/0.040(0.002), HgCl{sub 2} 0.015(0.001)/0.050(0.006), and MeHgCl 0.004(0.001)/0.005(0.001). Following EC{sub 50} values were found [LDH: mean (mmol/l); SEM in parentheses; n=12]: (24 h/48 h) HEMA 9.490(0.300)/7.890(1.230), TEGDMA 2.300(0.470)/1.950(0.310), UDMA 0.200(0.007)/0.100(0.007), BisGMA 0.070(0.005)/0.100(0.002), and MeHgCl 0.014(0.006)/0.010(0.003). In both assays, the following range of increased toxicity was found for composite components (24 and 48 h): HEMA < TEGDMA < UDMA < BisGMA. In both assays, MeHgCl was the most toxic substance. In the BrdU assay, Hg{sup 2+} was about fourfold less toxic than MeHgCl but Hg{sup 2+} was about fourfold more toxic than BisGMA. In the BrdU test, a significantly (P<0.05) decreased toxicity was observed for Hg{sup 2+} at 48 h, compared to the 24 h

  8. Soluble curcumin amalgamated chitosan microspheres augmented drug delivery and cytotoxicity in colon cancer cells: In vitro and in vivo study.

    Science.gov (United States)

    Jyoti, Kiran; Bhatia, Richa Kaur; Martis, Elvis A F; Coutinho, Evans C; Jain, Upendra Kumar; Chandra, Ramesh; Madan, Jitender

    2016-12-01

    In present investigation, initially curcumin was complexed with 2-HP-β-CD (curcumin-2-HP-β-CD-complex) in 1:1 ratio and later amalgamated with chitosan microspheres (curcumin-2-HP-β-CD-CMs) for selective delivery in colon only through oral route of administration. Various analytical, spectral and in-silico docking techniques revealed that the curcumin was deeply inserted in the 2-HP-β-CD cavity with apparent stability constant of 3.35×10 -3 M. Furthermore, the mean particle size of 6.8±2.6μm and +39.2±4.1mV surface charge of curcumin-2-HP-β-CD-complex-CMs in addition to encapsulation efficiency of about 79.8±6.3% exhibited that the tailored microspheres were optimum for colon delivery of curcumin. This was also demonstrated in dissolution testing and standard cell proliferation assay in which curcumin-2-HP-β-CD-complex-CMs exhibited maximum release in simulated colonic fluid (SCF, pH ∼7.0-8.0, almond emulsion-β-glucosidase) with improved therapeutic index in HT-29 cells. Consistently, curcumin-2-HP-β-CD-complex-CMs successively enhanced the colonic bio-distribution of curcumin by ∼8.36 folds as compared to curcumin suspension in preclinical pharmacokinetic studies. In conclusion, curcumin-2-HP-β-CD-complex-CMs warrant further in vivo tumor regression study to establish its therapeutic efficacy in experimental colon cancer. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Form Filling with Self-Compacting Concrete

    DEFF Research Database (Denmark)

    Thrane, Lars Nyholm

    2002-01-01

    This paper describes a newly started Ph.D. project with the aim of simulating the form filling ability of Self-Compacting Concrete (SCC) taking into account the form geometry, reinforcement configuration, casting technique, and the rheological properties of the concrete. Comparative studies...

  10. Stock keeping unit fill rate specification

    NARCIS (Netherlands)

    Teunter, R. H.; Syntetos, A. A.; Babai, M. Z.

    2017-01-01

    The fill rate is the most widely applied service level measure in industry and yet there is minimal advice available on how it should be differentiated on an individual Stock Keeping Unit (SKU) basis given that there is an overall system target service level. The typical approach utilized in

  11. New Skeletal-Space-Filling Models

    Science.gov (United States)

    Clarke, Frank H.

    1977-01-01

    Describes plastic, skeletal molecular models that are color-coded and can illustrate both the conformation and overall shape of small molecules. They can also be converted to space-filling counterparts by the additions of color-coded polystyrene spheres. (MLH)

  12. Safety distances for hydrogen filling stations

    NARCIS (Netherlands)

    Matthijsen, A J C M; Kooi, E S

    2006-01-01

    In the context of spatial planning the Dutch Ministry of Housing, Spatial Planning and the Environment asked the Centre for External Safety of the National Institute for Public Health and the Environment (RIVM) to advice on safe distances pertaining to hydrogen filling stations. The RIVM made use of

  13. Banach spaces that realize minimal fillings

    International Nuclear Information System (INIS)

    Bednov, B. B.; Borodin, P. A.

    2014-01-01

    It is proved that a real Banach space realizes minimal fillings for all its finite subsets (a shortest network spanning a fixed finite subset always exists and has the minimum possible length) if and only if it is a predual of L 1 . The spaces L 1 are characterized in terms of Steiner points (medians). Bibliography: 25 titles. (paper)

  14. INS gas-filled recoil isotope separator

    International Nuclear Information System (INIS)

    Miyatake, M.; Nomura, T.; Kawakami, H.

    1986-09-01

    The characteristics and performance of a small sized gas-filled recoil isotope separator recently made at INS are described. The total efficiency and the ΔBρ/Bρ values have been measured using low velocity 16 O, 40 Ar and 68 As ions and found to be 10 and 5 %, respectively. The Z-dependence of the mean charge is discussed. (author)

  15. Stability of fruit bases and chocolate fillings

    Directory of Open Access Journals (Sweden)

    Joice Natali Miquelim

    2011-03-01

    Full Text Available Syrups with high sugar content and dehydrated fruits in its composition can be added to chocolate fillings to reduce the need of artificial flavor and dyes attributing a natural appeal to the product. Fruit bases were produced with lyophilized strawberry, passion fruit, and sliced orange peel. Rheological dynamic oscillatory tests were applied to determine the products stability and tendency of shelf life. Values of G´ G´´ were found for orange flavor during the 90 days of storage. It was observed that shear stress values did not vary significantly suggesting product stability during the studied period. For all fillings, it was found a behavior similar to the fruit base indicating that it has great influence on the filling behavior and its stability. The use of a sugar matrix in fillings provided good shelf life for the fruit base, which could be kept under room temperature conditions for a period as long as one year. The good stability and storage conditions allow the use of fruit base for handmade products as well as for industrialized products.

  16. Full-waveform inversion: Filling the gaps

    KAUST Repository

    Beydoun, Wafik B.; Alkhalifah, Tariq Ali

    2015-01-01

    After receiving an outstanding response to its inaugural workshop in 2013, SEG once again achieved great success with its 2015 SEG Middle East Workshop, “Full-waveform inversion: Filling the gaps,” which took place 30 March–1 April 2015 in Abu Dhabi

  17. Safety Distances for hydrogen filling stations

    Energy Technology Data Exchange (ETDEWEB)

    Matthijsen, A. J. C. M.; Kooi, E. S.

    2005-07-01

    In the Netherlands there is a growing interest in using natural gas as a transport fuel. The most important drivers behind this development are formed by poor inner city air quality and the decision to close several LPG filling stations. Dwellings are not allowed within the safety distances of 45 or 110 meters from the tanker filling point of these LPG stations, depending on the capacity of the station. Another driver is global warming. We are carrying out a study on station supply, compression, storage and filling for natural gas stations, and a similar, simultaneous study on hydrogen as a followup to our risk analysis for the hydrogen filling station in Amsterdam. Here, three buses drive on hydrogen as part of the European CUTE project. Driving on natural gas is an important step in the transition to cars on hydrogen. This study was commissioned by the Dutch Ministry of Spatial Planning, Housing and the Environment to advise on external safety aspects of future hydrogen filling stations. According to Dutch law homes may not be built within an individual risk contour of 10-6 per year of a dangerous object, such as a plant with hazardous materials or a filling station. An individual risk contour of 10-6 is represented by a line around a dangerous object that connects locations with an individual risk level of 10-6 per year. An individual 'located' within this contour line has a chance of one per million per year or more to be killed as a result of an accident caused by this object. The longest distance between the object and such a contour is called a 'safety distance'. A study on safety distances is now in progress for different kinds of hydrogen filling stations (e. g. gaseous and liquid hydrogen) and for different capacities, such as big, medium and small stations. The focus is on different kinds of hydrogen production and the hydrogen supply of the filling station. To decide on the design and supply of the hydrogen station, we examined the

  18. Root canal filling using Resilon: a review.

    LENUS (Irish Health Repository)

    Shanahan, D J

    2011-07-01

    Root canal treatment is achieved by chemo-mechanical debridement of the root canal system followed by filling. The filling material \\'entombs\\' residual bacteria and acts as a barrier which prevents the entrance of oral microorganisms and reinfection of the root canal system through microleakage. However, filling with contemporary root filling materials such as gutta-percha offers limited long-term resistance to microorganisms; as a result other materials such as Resilon have been investigated as alternatives. The aim of this review was to analyse the literature to consider whether Resilon is a suitable root canal filling material. A MEDLINE and Cochrane library search including various keyword searches identified several papers which investigated or discussed Resilon or RealSeal\\/Epiphany. Analysis of the literature demonstrated that the bulk of the literature is in vitro in nature, based largely on leakage-type studies, and demonstrates a wide variety of methodologies with conflicting findings; as a result meaningful conclusions are difficult. Within the limit of these in vitro studies Resilon appears to perform adequately in comparison to gutta-percha, however, as a result of the questionable merit of such studies, it cannot presently be considered an evidence-based alternative to the current gold standard gutta-percha. It is imperative that before Resilon is considered as a replacement material, a better understanding of the physical properties of the resin sealer and the reality of the adhesive \\'monoblock\\' are elucidated. The literature also demonstrates a paucity of quality long-term clinical outcome studies which will need to be addressed before firm conclusions can be reached.

  19. Late Paleozoic closure of the Ob-Zaisan Ocean along the Irtysh/Chara shear zone and implications for arc amalgamation and oroclinal bending in the western Central Asian Orogenic Belt

    Science.gov (United States)

    Li, Pengfei; Sun, Min; Rosenbaum, Gideon

    2016-04-01

    The Irtysh/Chara Shear Zone is one of the largest strike-slip systems in the Central Asian Orogenic Belt (CAOB). It records collisional processes of the peri-Siberian orogenic system with the West Junggar-Kazakhstan-Tianshan orogenic system following the closure of the Ob-Zaisan Ocean, but the exact timing of these events remains enigmatic. We conducted detailed structural analysis along the Irtysh Shear Zone (NW China), which together with new geochronological data allows us to reconstruct the tectonic evolution during the final closure of the Ob-Zaisan Ocean. Our results showed that subduction-accretion processes lasted at least until the Late Carboniferous in the Chinese Altai and the East/West Junggar. The subsequent arc amalgamation is characterized by a cycle of crustal thickening, orogenic collapse and transpressional thickening. On a larger scale, the West Junggar- Kazakhstan -Tianshan orogenic system defines a U-shape oroclinal structure (e.g. Xiao et al., 2010). A major phase of oroclinal bending that involved ~110° rotation may have occurred during the Late Devonian to Early Carboniferous (Levashova et al., 2012). Previous authors have linked oroclinal bending with the late Paleozoic amalgamation of the western CAOB, and proposed that a quasi-linear West Junggar- Kazakhstan -Tianshan orogenic system was buckled during the convergence of the Siberian and Tarim cratons following the closure of the Ob-Zaisan Ocean (in the north) and the South Tianshan Ocean (in the south) (e.g. Abrajevitch et al., 2008). This model, however, is not supported by our new data that constrain the closure of the Ob-Zaisan Ocean to the Late Carboniferous. Alternatively, we propose that oroclinal bending may have involved two phases of bending, with the ~110° rotation in the Late Devonian to Early Carboniferous possibly associated with trench retreat. Further tightening may have occurred in response to the convergence of the Siberian and Tarim cratons during the Late

  20. Cardiovascular responses to apneic facial immersion during altered cardiac filling.

    Science.gov (United States)

    Journeay, W Shane; Reardon, Francis D; Kenny, Glen P

    2003-06-01

    The hypothesis that reduced cardiac filling, as a result of lower body negative pressure (LBNP) and postexercise hypotension (PEH), would attenuate the reflex changes to heart rate (HR), skin blood flow (SkBF), and mean arterial pressure (MAP) normally induced by facial immersion was tested. The purpose of this study was to investigate the cardiovascular control mechanisms associated with apneic facial immersion during different cardiovascular challenges. Six subjects randomly performed 30-s apneic facial immersions in 6.0 +/- 1.2 degrees C water under the following conditions: 1) -20 mmHg LBNP, 2) +40 mmHg lower body positive pressure (LBPP), 3) during a period of PEH, and 4) normal resting (control). Measurements included SkBF at one acral (distal phalanx of the thumb) and one nonacral region of skin (ventral forearm), HR, and MAP. Facial immersion reduced HR and SkBF at both sites and increased MAP under all conditions (P filling during LBNP and PEH significantly attenuated the absolute HR nadir observed during the control immersion (P facial immersion can be attenuated when cardiac filling is compromised.

  1. Integration of different data gap filling techniques to facilitate ...

    Science.gov (United States)

    Data gap filling techniques are commonly used to predict hazard in the absence of empirical data. The most established techniques are read-across, trend analysis and quantitative structure-activity relationships (QSARs). Toxic equivalency factors (TEFs) are less frequently used data gap filling techniques which are applied to estimate relative potencies for mixtures of chemicals that contribute to an adverse outcome through a common biological target. For example, The TEF approach has been used for dioxin-like effects comparing individual chemical activity to that of the most toxic dioxin: 2,3,7,8-tetrachlorodibenzo-p-dioxin. The aim of this case study was to determine whether integration of two data gap filling techniques: QSARs and TEFs improved the predictive outcome for the assessment of a set of polychlorinated biphenyl (PCB) congeners and their mixtures. PCBs are associated with many different adverse effects, including their potential for neurotoxicity, which is the endpoint of interest in this study. The dataset comprised 209 PCB congeners, out of which 87 altered in vitro Ca(2+) homeostasis from which neurotoxic equivalency values (NEQs) were derived. The preliminary objective of this case study was to develop a QSAR model to predict NEQ values for the 122 untested PCB congeners. A decision tree model was developed using the number of position specific chlorine substitutions on the biphenyl scaffold as a fingerprint descriptor. Three different positiona

  2. Innovations in endodontic filling materials: guttapercha vs Resilon.

    Science.gov (United States)

    de Souza Filho, Francisco José; Gallina, Giuseppe; Gallottini, Livio; Russo, Riccardo; Cumbo, Enzo Maria

    2012-01-01

    One of the goals of endodontic treatment is to achieve a complete, tridimensional, hermetic sealing of the root canal system to prevent the entry of microorganisms or their products through both the coronal and apical pathways. Gutta-percha is the most widely used material for root canal filling and despite its numerous properties, such as biocompatibility and thermoplasticity, it has however an important limit: the lack of adhesion to the canal walls. Attempts to address this problem have been made over the years by using endodontic cements capable of bonding to canal dentine but their tendency to resorption in time can compromise the quality of treatment. The first step towards a real adhesive endodontic filling(4) is rather recent; in fact, it goes back to 2003 when, on the occasion of the American Dental Association (ADA) Annual Session, Resilon Research LLC introduced a new canal filling adhesive system based on a thermoplastic synthetic resin material called Resilon™. The real innovation of this system is its capacity of creating a core made of Resilon™ bonded to the cement which adheres to dentine walls previously conditioned with a self-etching primer(4) so no changes in the techniques of canal preparation are required. The aim of this study was to evaluate the capacity of two filling materials (gutta-percha and Resilon) to adapt to the canal anatomy, especially on the apical third, using the continuous wave of condensation technique. Our data suggest that in the third apical the gutta-percha best shows rheological properties that are as important as the bond capability.

  3. The order and volume fill rates in inventory control systems

    DEFF Research Database (Denmark)

    Thorstenson, Anders; Larsen, Christian

    2011-01-01

    This paper differentiates between an order (line) fill rate and a volume fill rate and specifies their performance for different inventory control systems. When the focus is on filling complete customer orders rather than total quantities the order fill rate would be the preferred service level m...

  4. Target-induced formation of gold amalgamation on DNA-based sensing platform for electrochemical monitoring of mercury ion coupling with cycling signal amplification strategy.

    Science.gov (United States)

    Chen, Jinfeng; Tang, Juan; Zhou, Jun; Zhang, Lan; Chen, Guonan; Tang, Dianping

    2014-01-31

    Heavy metal ion pollution poses severe risks in human health and environmental pollutant, because of the likelihood of bioaccumulation and toxicity. Driven by the requirement to monitor trace-level mercury ion (Hg(2+)), herein we construct a new DNA-based sensor for sensitive electrochemical monitoring of Hg(2+) by coupling target-induced formation of gold amalgamation on DNA-based sensing platform with gold amalgamation-catalyzed cycling signal amplification strategy. The sensor was simply prepared by covalent conjugation of aminated poly-T(25) oligonucleotide onto the glassy carbon electrode by typical carbodiimide coupling. Upon introduction of target analyte, Hg(2+) ion was intercalated into the DNA polyion complex membrane based on T-Hg(2+)-T coordination chemistry. The chelated Hg(2+) ion could induce the formation of gold amalgamation, which could catalyze the p-nitrophenol with the aid of NaBH4 and Ru(NH3)6(3+) for cycling signal amplification. Experimental results indicated that the electronic signal of our system increased with the increasing Hg(2+) level in the sample, and has a detection limit of 0.02nM with a dynamic range of up to 1000nM Hg(2+). The strategy afforded exquisite selectivity for Hg(2+) against other environmentally related metal ions. In addition, the methodology was evaluated for the analysis of Hg(2+) in spiked tap-water samples, and the recovery was 87.9-113.8%. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. Flammability of Gas-Filled Polymers

    Directory of Open Access Journals (Sweden)

    Ushkov Valentin Anatol'evich

    2017-09-01

    Full Text Available The regularities of flame propagation on the horizontal surface of gas-filled polymers are considered depending on the concentration of oxygen in the oxidizer flow. The values of the coefficients in the expression describing relationship between the rate of flame propagation on the surface of foams and oxygen concentration are obtained. It was shown that with the mass content of reactive organophosphorus compounds reaching 4.0...5.9%, non-smoldering resole foam plastics with high performance characteristics are obtained. It was found that in order to obtain moderately combustible polyurethane foams based on oxyethylated phosphorus-containing polyols, the phosphorus concentration should not exceed 3 % of mass. To obtain flame-retardant urea-formaldehyde foam cellular plastics, the concentration of phosphorus should not exceed 0.3 % of mass. Physical-mechanical properties and flammability indices of developed gas-filled polymers based on reactive oligomers are presented.

  6. Form Filling with Self-Compacting Concrete

    DEFF Research Database (Denmark)

    Thrane, Lars Nyholm

    2007-01-01

    to the prospects of improving the structural quality, working environment, productivity, and architectural appearance. However, especially in vertical applications there is a great unused potential. Controlling the casting process is important in many different industries such as the metal, plastic, and food...... the framework of Computational Fluid Dynamics (CFD). CFD is applied to simulate the homogeneous form filling characteristics, i.e. the form filling ability and flow patterns, taking into account the rheological properties and casting technique. It is assumed that the rheological properties of SCC follow...... dimensions. For the heterogeneous flow phenomena, this project focusses on the assessment of blocking, which is of special interest in relation to high quality and complicated structures with a dense reinforcement configuration. A phenomenological micro-mechanical model has been developed, which introduces...

  7. Rainwater drained through fully filled pipes

    Energy Technology Data Exchange (ETDEWEB)

    Kuhn, B; Koestel, P

    1989-02-01

    The conventional rainwater drainage system according to DIN 1986 always seems to be a point of problemacy in the building services as far as the occupancy of installation shafts and ducts is at stake. The excavation work and the necessary gravity lines are considered to be expensive. The consideration of the necessary slope complicates the installation additionally. Basing on those considerations, the raindraining system with fully filled pipes has been developed. DIN 1986, edition June 1988, part 1, point 6.1.1 allows to install rainwater pipes operated as planned, fully filled without slope. An enterprise specialised in building services investigated all system laws because only by a hydraulically exact balance, the function of the rainwater drainage system operated by negative and positive pressure can be insured. The results of those investigations are integrated in a computer program developed for this purpose.

  8. Air filled porosity in composting processes

    Energy Technology Data Exchange (ETDEWEB)

    Ruggieri, L.; Gea, T.; Artola, A.; Sanchez, A.

    2009-07-01

    As it is widely known, the composting process consists in the aerobic decomposition of the biodegradable organic matter present in different types of solid wastes. Water and oxygen are necessary for the biological activity of microorganisms involved in the composting process and their availability is directly related to the total and the air filled porosity (AFP). Maintaining adequate AFP level satisfies the oxygen content requirement to achieve the desired composting conditions and thus, tho enhance biological activity. (Author)

  9. Moon - 'Ghost' craters formed during Mare filling.

    Science.gov (United States)

    Cruikshank, D. P.; Hartmann, W. K.; Wood, C. A.

    1973-01-01

    This paper discusses formation of 'pathological' cases of crater morphology due to interaction of craters with molten lavas. Terrestrial observations of such a process are discussed. In lunar maria, a number of small impact craters (D less than 10 km) may have been covered by thin layers of fluid lavas, or formed in molten lava. Some specific lunar examples are discussed, including unusual shallow rings resembling experimental craters deformed by isostatic filling.

  10. Mobile myelographic filling defects: Spinal cysticercosis

    Energy Technology Data Exchange (ETDEWEB)

    Savoiardo, M.; Cimino, C.; Passerini, A.; La Mantia, L.

    1986-03-01

    Cysticercosis usually affects the brain and is easily demonstrated by CT. Spinal cysticercosis is much rarer and is usually diagnosed only at surgery. Myelographic demonstration of multiple rounded filling defects, some of which were mobile, allowed diagnosis of spinal extramedullary cysticercosis in an unsuspected case. The literature on spinal cysticercosis is briefly reviewed. Diagnosis is important in view of the recent development of medical treatment.

  11. The partially filled viscous ring damper.

    Science.gov (United States)

    Alfriend, K. T.

    1973-01-01

    The problem of a spinning satellite with a partially filled viscous ring damper is investigated. It is shown that there are two distinct modes of motion, the nutation-synchronous mode and spin-synchronous mode. From an approximate solution of the equations of motion a time constant is obtained for each mode. From a consideration of the fluid dynamics several methods are developed for determining the damping constant.

  12. Pulse formation of gas-filled counter

    International Nuclear Information System (INIS)

    Iwatani, Kazuo; Teshima, Kazunori; Shizuma, Kiyoshi; Hasai, Hiromi

    1991-01-01

    The pulse formation of gas-filled counter has been calculated by simple models for the proportional and self-quenching streamer (SQS) modes. Calculated pulse shapes of counter output have accurately reproduced the observed ones for both modes. As a result, it is shown that the special density distribution of ion pairs in a streamer can be estimated with the rising part of observed pulse shape, using the model. (author)

  13. Full-waveform inversion: Filling the gaps

    KAUST Repository

    Beydoun, Wafik B.

    2015-09-01

    After receiving an outstanding response to its inaugural workshop in 2013, SEG once again achieved great success with its 2015 SEG Middle East Workshop, “Full-waveform inversion: Filling the gaps,” which took place 30 March–1 April 2015 in Abu Dhabi, UAE. The workshop was organized by SEG, and its partner sponsors were Saudi Aramco (gold sponsor), ExxonMobil, and CGG. Read More: http://library.seg.org/doi/10.1190/tle34091106.1

  14. Air filled porosity in composting processes

    International Nuclear Information System (INIS)

    Ruggieri, L.; Gea, T.; Artola, A.; Sanchez, A.

    2009-01-01

    As it is widely known, the composting process consists in the aerobic decomposition of the biodegradable organic matter present in different types of solid wastes. Water and oxygen are necessary for the biological activity of microorganisms involved in the composting process and their availability is directly related to the total and the air filled porosity (AFP). Maintaining adequate AFP level satisfies the oxygen content requirement to achieve the desired composting conditions and thus, tho enhance biological activity. (Author)

  15. Long-term observation of endodontic surgical intervention to treat root perforation and apical periodontitis: a case report of an amalgam-restored tooth.

    Science.gov (United States)

    Tsurumachi, Tamotsu; Hayashi, Makoto

    2003-10-01

    A case of crestal root perforation and periapical lesion in a maxillary left lateral incisor is reported. Teeth with root perforation present technical difficulties in their clinical management because of their complex defects. In the present case, surgical endodontic treatment was chosen. The apical and lateral pathology was curetted, the tooth root was resected, and a retrograde root restoration of amalgam was placed in a root-end cavity and perforation site. A 10-year follow-up clinical and radiographic examination showed an asymptomatic tooth with osseous healing proceeding.

  16. Soil and minespoil fill as media for renovation of nitrogen and phosphorus in domestic wastewater

    International Nuclear Information System (INIS)

    Peterson, C.E.; Reneau, R.B. Jr.; Hagedorn, C.

    1998-01-01

    Development of US Appalachian coal mining regions has been hampered by lack of domestic waste disposal technologies suited to fills. The suitability of on-site wastewater treatment and disposal systems (OSWTDS) in fill material is uncertain due to the effects of surface mining on soil physical properties. This research evaluated the potential for renovation of N and P present in domestic wastewater by fills from mining operations. N and P were chosen because of their potential adverse environmental impacts. Soil-fill (a mixture of Jefferson, fine-loamy, siliceous, mesic Typic Hapludult and Muskingom, fine-loamy, mixed, mesic Typic Dystrochrept soils) and minespoil (spoil)-fill (blasted rock material associated with the Taggart Marker and Low Splint Bench coal seams of the Upper Middle Wise Formation) were used. Septic tank effluent (STE) and sand filter effluent (SFE) were applied to spoil-fill columns at four loading rates and spoil-fill columns at one loading rate for a period of 20 wk. Renovation of wastewater was assessed by determining the concentration of N and P present in column leachate. Reduction of inorganic N(NO 3 - + NH 4 + ), based on N/Cl ratios ranged from 14.9 to 32.1% after the varying application rates of STE and SFE passed through the soil columns. However, leachate NO 3 - -N concentrations were still above the 10 mg -1 drinking water standard. The quantity of P emerging from the spoil-fill columns (3.0 mg PL -1 ) was higher than anticipated and may be related to the indigenous P present in the minespoil. Sorption of P in the spoil-fill column decreased with increased STE and SFE application (reduction ranged from 99.1 to 74.4%). Results from this study indicate that there is potential for renovating wastewater in OSWTDS in selected soil-fill areas in reclaimed minelands. 33 refs., 2 figs., 4 tabs

  17. Boron filled siloxane polymers for radiation shielding

    Science.gov (United States)

    Labouriau, Andrea; Robison, Tom; Shonrock, Clinton; Simmonds, Steve; Cox, Brad; Pacheco, Adam; Cady, Carl

    2018-03-01

    The purpose of the present work was to evaluate changes to structure-property relationships of 10B filled siloxane-based polymers when exposed to nuclear reactor radiation. Highly filled polysiloxanes were synthesized with the intent of fabricating materials that could shield high neutron fluences. The newly formulated materials consisted of cross-linked poly-diphenyl-methylsiloxane filled with natural boron and carbon nanofibers. This polymer was chosen because of its good thermal and chemical stabilities, as well as resistance to ionizing radiation thanks to the presence of aromatic groups in the siloxane backbone. Highly isotopically enriched 10B filler was used to provide an efficient neutron radiation shield, and carbon nanofibers were added to improve mechanical strength. This novel polymeric material was exposed in the Annular Core Research Reactor (ACRR) at Sandia National Labs to five different neutron/gamma fluxes consisting of very high neutron fluences within very short time periods. Thermocouples placed on the specimens recorded in-situ temperature changes during radiation exposure, which agreed well with those obtained from our MCNP simulations. Changes in the microstructural, thermal, chemical, and mechanical properties were evaluated by SEM, DSC, TGA, FT-IR NMR, solvent swelling, and uniaxial compressive load measurements. Our results demonstrate that these newly formulated materials are well-suitable to be used in applications that require exposure to different types of ionizing conditions that take place simultaneously.

  18. MORPHOLOGICAL FILLING OF DIGITAL ELEVATION MODELS

    Directory of Open Access Journals (Sweden)

    T. Krauß

    2012-09-01

    Full Text Available In this paper a new approach for a more detailed post processing and filling of digital elevation models (DEMs in urban areas is presented. To reach the required specifications in a first step the errors in digital surface models (DSMs generated by dense stereo algorithms are analyzed and methods for detection and classification of the different types of errors are implemented. Subsequently the classified erroneous areas are handled in separate manner to eliminate outliers and fill the DSM properly. The errors which can be detected in DSMs range from outliers – single pixels or small areas containing extremely high or low values – over noise from mismatches, single small holes to occlusions, where large areas are not visible in one of the images of the stereo pair. To validate the presented method artificial DSMs are generated and superimposed with all different kinds of described errors like noise (small holes cut in, outliers (small areas moved up/down, occlusions (larger areas beneath steep walls and so on. The method is subsequently applied to the artificial DSMs and the resulting filled DSMs are compared to the original artificial DSMs without the introduced errors. Also the method is applied to stereo satellite generated DSMs from the ISPRS Comission 1 WG4 benchmark dataset and the results are checked with the also provided first pulse laser DSM data. Finally the results are discussed, strengths and weaknesses of the approach are shown and suggestions for application and optimization are given.

  19. Mercury health effects among the workers extracting gold from carpets and dusted clays through amalgamation and roasting processes.

    Science.gov (United States)

    Gul, Nayab; Khan, Sardar; Khan, Abbas; Ahmad, Sheikh Saeed

    2015-11-01

    Mercury (Hg) is a highly toxic metal which can cause serious health effects. The aim of this research was to determine the concentrations of total Hg (T-Hg), methyl Hg (Me-Hg), and inorganic Hg (I-Hg) in the biological samples (plasma, red blood cells (RBCs), urine, hair, and nails) of the exposed goldsmith workers. This is the first study that determines the detailed Hg concentrations in the biological samples (plasma, RBCs, urine, hair, and nails) of the exposed goldsmith workers and correlates them with the diseases noted among the workers in a single paper. Biological samples were collected from goldsmith workers (n = 40) and analyzed for T-Hg, Me-Hg, and I-Hg using atomic absorption spectrometer equipped with mercury hydride system. The mean T-Hg concentration in RBCs (33 μg L(-1)), plasma (11.8 μg L(-1)), urine (167 μg L(-1)), hair (4.21 μg g(-1)), and nails (5.91 μg g(-1)) were higher than the control RBCs (1.64 μg L(-1)), plasma (0.55 μg L(-1)), urine (2.72 μg L(-1)), hair (0.35 μg g(-1)), and nails (0.51 μg g(-1)). All workers participated in this study were suffering from physical and mental diseases. The concentration of Hg was found higher among the workers suffering from mental diseases as compared to those suffering from physical diseases. Among the physical diseases, the most serious diseases were sexual dysfunction, skin diseases, and fatigue because the workers suffering from these diseases had higher concentration of Hg than the workers with other diseases. The occurrence of physical diseases (88%) was greater than the mental diseases (53%) among the workers. The correlations of physical and mental diseases with experience (years of work) and exposure time were significant (p  0.05) correlation was observed between demographic parameters and Hg concentrations in the biological samples of the workers. The burning process of amalgamated gold is a significant source of Hg exposure to goldsmith workers; therefore, awareness and

  20. Identification and Characterization of microRNAs during Maize Grain Filling.

    Science.gov (United States)

    Jin, Xining; Fu, Zhiyuan; Lv, Panqing; Peng, Qian; Ding, Dong; Li, Weihua; Tang, Jihua

    2015-01-01

    The grain filling rate is closely associated with final grain yield of maize during the period of maize grain filling. To identify the key microRNAs (miRNAs) and miRNA-dependent gene regulation networks of grain filling in maize, a deep-sequencing technique was used to research the dynamic expression patterns of miRNAs at four distinct developmental grain filling stages in Zhengdan 958, which is an elite hybrid and cultivated widely in China. The sequencing result showed that the expression amount of almost all miRNAs was changing with the development of the grain filling and formed in seven groups. After normalization, 77 conserved miRNAs and 74 novel miRNAs were co-detected in these four samples. Eighty-one out of 162 targets of the conserved miRNAs belonged to transcriptional regulation (81, 50%), followed by oxidoreductase activity (18, 11%), signal transduction (16, 10%) and development (15, 9%). The result showed that miRNA 156, 393, 396 and 397, with their respective targets, might play key roles in the grain filling rate by regulating maize growth, development and environment stress response. The result also offered novel insights into the dynamic change of miRNAs during the developing process of maize kernels and assisted in the understanding of how miRNAs are functioning about the grain filling rate.

  1. Electrospun nanofibers decorated with bio-sonochemically synthesized gold nanoparticles as an ultrasensitive probe in amalgam-based mercury (II) detection system.

    Science.gov (United States)

    Parsaee, Zohreh

    2018-06-01

    In this study, bio-ultrasound-assisted synthesized gold nanoparticles using Gracilaria canaliculata algae have been immobilized on a polymeric support and used as a glassy probe chemosensor for detection and rapid removal of Hg 2+ ions. The function of the suggested chemosensor has been explained based on gold-amalgam formation and its catalytic role on the reaction of sodium borohydride and rhodamine B (RhB) with fluorescent and colorimetric sensing function. The catalyzed reduction of RhB by the gold amalgam led to a distinguished color change from red and yellow florescence to colorless by converting the amount of Hg 2+ deposited on Au-NPs. The detection limit of the colorimetric and fluorescence assays for Hg 2+ was 2.21 nM and 1.10 nM respectively. By exposing the mentioned colorless solution to air for at least 2 h, unexpectedly it was observed that the color and fluorescence of RhB were restored. Have the benefit of the above phenomenon a recyclable and portable glass-based sensor has been provided by immobilizing the Au-NPs and RB on the glass slide using electrospinning. Moreover, the introduced combinatorial membrane has facilitated the detection and removal of Hg 2+ ions in various Hg (II)-contaminated real water samples with efficiency of up to 99%. Copyright © 2018 Elsevier B.V. All rights reserved.

  2. Complications of cataract surgery in eyes filled with silicone oil.

    Science.gov (United States)

    Kanclerz, Piotr; Grzybowski, Andrzej; Schwartz, Stephen G; Lipowski, Paweł

    2018-03-01

    The aim of the study was to evaluate complications of cataract surgery in eyes filled with silicone oil. This retrospective, noncomparative, consecutive case series analyzed medical files of patients with eyes filled with silicone oil undergoing cataract surgery. Phacoemulsification with posterior chamber intraocular lens implantation was conducted with or without concurrent silicone oil removal. In this study, 121 eyes of 120 patients were included. In 32 eyes (26.4%) with evident silicone oil microemulsification or silicone oil-associated open-angle glaucoma, silicone oil was removed prior to phacoemulsification through a pars plana incision and no cases of posterior capsular rupture occurred during the subsequent cataract surgery. In the remaining 89 eyes, phacoemulsification was performed with silicone oil in the vitreous cavity. In these eyes, the rate of posterior capsular rupture was 9/89 (10.1%) and the rate of silicone oil migration into the anterior chamber through an apparently intact posterior capsule was 5/89 (5.6%). In 94 eyes (77.7%), an intraocular lens was inserted into the capsular bag, in 3 eyes (2.5%) into the sulcus, and in 1 eye (0.8%) a transscleral suturing was performed. In this series, complications related to the silicone oil were not uncommon during cataract surgery. In the majority of patients without evident silicone oil microemulsification or silicone oil-associated open-angle glaucoma, cataract surgery and posterior chamber intraocular lens implantation were performed while leaving the silicone oil in place.

  3. The effect of tube filling on the electronic properties of Fe filled carbon nanotubes

    International Nuclear Information System (INIS)

    Linganiso, Ella C.; Chimowa, George; Franklyn, Paul J.; Bhattacharyya, Somnath; Coville, Neil J.

    2012-01-01

    Graphical abstract: HRTEM image of a twisted CNT filled with a bent single crystal of Fe. Insets from top to bottom show the power spectra of the corresponding regions, indicating the twisting of the Fe lattice. Inset in the top right shows the relative angling of the lattice fringes to accommodate the twisting of the Fe. Highlights: ► Synthesis of Fe filled CNTs with Fe content varying from 3 to 35%. ► TEM analysis indicates that Fe in the tubes is in contact with the CNTs. ► TEM analysis reveals that α-Fe crystallizes after CNT formation. ► Temperature dependent electronic transport measurements performed. ► Conductivity varies with the % Fe filling in the CNTs. - Abstract: Carbon nanotubes filled with Fe nanostructures (Fe-CNTs) were synthesized using an injection method in a 1-stage horizontal CVD furnace and a bubbling method in a 2-stage horizontal CVD reactor. Fe-CNTs were obtained through the pyrolysis of a mixture of dichlorobenzene and ferrocene in 5%H 2 /Ar. Metal impurities from the Fe-CNTs were removed using 1 M HCl solution. CNTs filled with crystalline Fe nanoparticles, nanorods and nanowires were obtained using these procedures. An intimate interaction between the Fe and the CNT was established by HRTEM studies. The α-Fe phase was observed to be the most dominant fraction found in the synthesized Fe-CNTs. The Fe 2 O 3 residue obtained from the TGA analysis revealed the amount of Fe filled inside the CNTs and this ranged between 3 and 31% by mass after purification. The temperature dependence of the conductivity in the temperature range between 2.5 and 100 K for an entangled network of Fe-CNTs was measured. An increase in conductivity due to the increased Fe filling inside the CNTs with increased temperature was observed. The observed temperature dependence was explained in terms of variable range hopping (VRH) conduction mechanisms. A transition from Efros–Shklovskii behavior at low % Fe filling of the CNTs to Mott 3D VRH behavior at

  4. Multiple scattering theory for space filling potentials

    International Nuclear Information System (INIS)

    Butler, W.H.; Brown, R.G.; Nesbet, R.K.

    1990-01-01

    Multiple scattering theory (MST) provides an efficient technique for solving the wave equation for the special case of muffin-tin potentials. Here MST is extended to treat space filling non-muffin tin potentials and its validity, accuracy and efficiency are tested by application of the two dimensional empty lattice test. For this test it is found that the traditional formulation of MST does not coverage as the number of partial waves is increased. A simple modification of MST, however, allows this problem to be solved exactly and efficiently. 15 refs., 3 tabs

  5. Hydraulic fracturing of rock-fill dam

    Directory of Open Access Journals (Sweden)

    Jun-Jie WANG

    2016-02-01

    Full Text Available The condition in which hydraulic fracturing in core of earth-rock fill dam maybe induced, the mechanism by which the reason of hydraulic fracturing canbe explained, and the failure criterion by which the occurrence of hydraulicfracturing can be determined, were investigated. The condition dependson material properties such as, cracks in the core and low permeability ofcore soil, and “water wedging” action in cracks. An unsaturated core soiland fast impounding are the prerequisites for the formation of “waterwedging” action. The mechanism of hydraulic fracturing can be explainedby fracture mechanics. The crack propagation induced by water pressuremay follow any of mode I, mode II and mixed mode I-II. Based on testingresults of a core soil, a new criterion for hydraulic fracturing was suggested,from which mechanisms of hydraulic fracturing in the core of rock-fill damwere discussed. The results indicated that factors such as angle betweencrack surface and direction of principal stress, local stress state at thecrack, and fracture toughness KIC of core soil may largely affect theinduction of hydraulic fracturing and the mode of the propagation of thecrack.The condition in which hydraulic fracturing in core of earth-rock fill dam maybe induced, the mechanism by which the reason of hydraulic fracturing canbe explained, and the failure criterion by which the occurrence of hydraulicfracturing can be determined, were investigated. The condition dependson material properties such as, cracks in the core and low permeability ofcore soil, and “water wedging” action in cracks. An unsaturated core soiland fast impounding are the prerequisites for the formation of “waterwedging” action. The mechanism of hydraulic fracturing can be explainedby fracture mechanics. The crack propagation induced by water pressuremay follow any of mode I, mode II and mixed mode I-II. Based on testingresults of a core soil, a new criterion for hydraulic fracturing

  6. Carbon Nanotubes Filled with Ferromagnetic Materials

    Directory of Open Access Journals (Sweden)

    Albrecht Leonhardt

    2010-08-01

    Full Text Available Carbon nanotubes (CNT filled with ferromagnetic metals like iron, cobalt or nickel are new and very interesting nanostructured materials with a number of unique properties. In this paper we give an overview about different chemical vapor deposition (CVD methods for their synthesis and discuss the influence of selected growth parameters. In addition we evaluate possible growth mechanisms involved in their formation. Moreover we show their identified structural and magnetic properties. On the basis of these properties we present different application possibilities. Some selected examples reveal the high potential of these materials in the field of medicine and nanotechnology.

  7. Carbon Nanotubes Filled with Ferromagnetic Materials

    Science.gov (United States)

    Weissker, Uhland; Hampel, Silke; Leonhardt, Albrecht; Büchner, Bernd

    2010-01-01

    Carbon nanotubes (CNT) filled with ferromagnetic metals like iron, cobalt or nickel are new and very interesting nanostructured materials with a number of unique properties. In this paper we give an overview about different chemical vapor deposition (CVD) methods for their synthesis and discuss the influence of selected growth parameters. In addition we evaluate possible growth mechanisms involved in their formation. Moreover we show their identified structural and magnetic properties. On the basis of these properties we present different application possibilities. Some selected examples reveal the high potential of these materials in the field of medicine and nanotechnology. PMID:28883334

  8. Le déficit de filles

    International Development Research Centre (IDRC) Digital Library (Canada)

    de la population est une tendance plus récente. C. Le déficit de filles. Le déséquilibre du ratio hommes-femmes en Inde. D. R. O. I. T. S. D. E. S. F. E. M. M. E. S. E. T. P. A. R. T. IC. I. P. A. T. IO. N. C. I. T. O. Y. E. N. N. E. CENTRE DE. RECHERCHES. POUR LE. DÉVELOPPEMENT. INTERNATIONAL. CRDI : Jason Taylor ...

  9. Evaluation of Flowable Fill Surface Performance

    Science.gov (United States)

    2016-11-01

    general, traditional flowable fill is a low- viscosity , grout-like, cementitious blend commonly composed of portland cement, fine aggregate, and water...93.7 45.0 19.6 % Finer No. 200 7.0 0.5 9.1 % Gravel 2.2 0.0 56.1 % Sand 90.8 99.5 34.8 % Silt 3.2 < 0.5 6.8 % Clay 3.8 < 0.5 2.3 Fineness Modulus

  10. The history of research on the filled pause as evidence of the written language bias in linguistics (Linell, 1982).

    Science.gov (United States)

    O'Connell, Daniel C; Kowal, Sabine

    2004-11-01

    Erard's (2004) publication in the New York Times of a journalistic history of the filled pause serves as the occasion for this critical review of the past half-century of research on the filled pause. Historically, the various phonetic realizations or instantiations of the filled pause have been presented with an odd recurrent admixture of the interjection ah. In addition, the filled pause has been consistently associated with both hesitation and disfluency. The present authors hold that such a mandatory association of the filled pause with disfluency is the product of The written language bias in linguistics [Linell, 1982] and disregards much cogent evidence to the contrary. The implicit prescriptivism of well formedness--a demand derived from literacy--must be rejected; literate well formedness is not a necessary or even typical property of spontaneous spoken discourse; its structures and functions--including those of the filled pause--are very different from those of written language The recent work of Clark and Fox Tree (2002) holds promise for moving the status of the filled pause not only toward that of a conventional word, but also toward its status as an interjection. This latter development is also being fostered by lexicographers. Nonetheless, in view of ongoing research regarding the disparate privileges of occurrence and functions of filled pauses in comparison with interjections, the present authors are reluctant to categorize the filled pause as an interjection.

  11. An interview study of persons who attribute health problems to dental filling materials--part two in a triangulation study on 65 and 75 years old Swedes.

    Science.gov (United States)

    Ståhlnacke, Katri; Söderfeldt, Björn

    2013-01-01

    Dental materials are perceived as a health problem by some people, although scientists do not agree about possible causes of such problems. The aim of this paper was to gain a deeper knowledge and understanding of experiences from living with health problems attributed to dental materials. Addressed topics were the type of problem, both as to general and oral health, perceived causes of the problems,their experienced effect on life, and reception by health professionals. Persons, who in a previous large questionnaire study had answered that they had experienced troubles from dental materials and also agreed to answer follow-up questions, were contacted with a request to take part in an interview study. Eleven individual interviews were held.The interviews were transcribed verbatim and the material was analysed according to the Qualitative Content Analysis method. Meaning units were extracted and condensed into a number of codes, which were combined into subcategories, categories, and themes. Four themes were identified: 1) Long-term oral, mental, and somatic difficulties of varying character, caused by dental amalgam. 2) Problems treated mainly by replacement of dental material in fillings. 3) Powerful effects on life, mostly negative. 4) The reception by health professionals was generally good, but with elements of encounters where they felt treated with nonchalance and lack of respect. In conclusion, people who attributed their health difficulties to dental materials had a complex range of problems and the perception was that amalgam/mercury was the cause of the troubles. The reception from health professionals was perceived as generally good, although with occasional negative experiences.

  12. Liquid-filled ionization chamber temperature dependence

    Energy Technology Data Exchange (ETDEWEB)

    Franco, L. [Dpto. de Fisica de Particulas, Facultade de Fisica, Universidade de Santiago, Campus Sur S/N, 15782 Santiago de Compostela (Spain)]. E-mail: luciaff@usc.es; Gomez, F. [Dpto. de Fisica de Particulas, Facultade de Fisica, Universidade de Santiago, Campus Sur S/N, 15782 Santiago de Compostela (Spain); Iglesias, A. [Dpto. de Fisica de Particulas, Facultade de Fisica, Universidade de Santiago, Campus Sur S/N, 15782 Santiago de Compostela (Spain); Pardo, J. [Dpto. de Fisica de Particulas, Facultade de Fisica, Universidade de Santiago, Campus Sur S/N, 15782 Santiago de Compostela (Spain); Pazos, A. [Dpto. de Fisica de Particulas, Facultade de Fisica, Universidade de Santiago, Campus Sur S/N, 15782 Santiago de Compostela (Spain); Pena, J. [Dpto. de Fisica de Particulas, Facultade de Fisica, Universidade de Santiago, Campus Sur S/N, 15782 Santiago de Compostela (Spain); Zapata, M. [Dpto. de Fisica de Particulas, Facultade de Fisica, Universidade de Santiago, Campus Sur S/N, 15782 Santiago de Compostela (Spain)

    2006-05-10

    Temperature and pressure corrections of the read-out signal of ionization chambers have a crucial importance in order to perform high-precision absolute dose measurements. In the present work the temperature and pressure dependences of a sealed liquid isooctane filled ionization chamber (previously developed by the authors) for radiotherapy applications have been studied. We have analyzed the thermal response of the liquid ionization chamber in a {approx}20 deg. C interval around room temperature. The temperature dependence of the signal can be considered linear, with a slope that depends on the chamber collection electric field. For example, a relative signal slope of 0.27x10{sup -2}K{sup -1} for an operation electric field of 1.67x10{sup 6}Vm{sup -1} has been measured in our detector. On the other hand, ambient pressure dependence has been found negligible, as expected for liquid-filled chambers. The thermal dependence of the liquid ionization chamber signal can be parametrized within the Onsager theory on initial recombination. Considering that changes with temperature of the detector response are due to variations in the free ion yield, a parametrization of this dependence has been obtained. There is a good agreement between the experimental data and the theoretical model from the Onsager framework.

  13. Fissure fillings from the Klipperaas study site

    International Nuclear Information System (INIS)

    Tullborg, E.L.

    1986-07-01

    The Klipperaas study site is located within the Smaaland-Vaermland granitoid belt in southern Sweden. The area investigated can be subdivided into blocks with different hydraulic character and fracture frequency of the rocks. A fissure filling, study has been carried out within the area. This includes identification of the minerals, mineral frequency, textures within the fissures and isotope analyses of calcites. Four generation of fissure fillings, within the time space c. 1600 M.a. to present, has been distinguished. These are 1) quartz; 2) epidote + muscovite and adularia + hematite; 3) calcite + chlorite +/hematite; 4) calcite, clay minerals and Fe-oxyhydroxide. It is observed that the surface water affect the uppermost part of the bedrock resulting in calcite dissolution, break down of pyrite and precipitation of Fe-oxyhydroxide. It is also obvious from the fracture calcite frequency that calcite dissolution is more intensive close to and within the fracture zones. There, Fe-oxyhydroxide can be found down to at least 400 m depth. This gives valuable information about the physic-chemical character of the groundwater within the bedrock. Several fracture zones have been reactivated. It is also suspected that relatively late movements have taken place causing crushing of the rock and only a slight cementation of the crushed material is visible. Some of the fracture zones correspond to mafic dikes. These zones exhibit lower hydraulic conductivity than other zones due to fracture sealing by clay minerals but also by chlorite and calcite. (author)

  14. GRAVITY PIPELINE TRANSPORT FOR HARDENING FILLING MIXTURES

    Directory of Open Access Journals (Sweden)

    Leonid KROUPNIK

    2015-12-01

    Full Text Available In underground mining of solid minerals becoming increasingly common development system with stowing hardening mixtures. In this case the natural ore array after it is replaced by an artificial excavation of solidified filling mixture consisting of binder, aggregates and water. Such a mixture is prepared on the surface on special stowing complexes and transported underground at special stowing pipelines. However, it is transported to the horizons of a few kilometers, which requires a sustainable mode of motion of such a mixture in the pipeline. Hardening stowing mixture changes its rheological characteristics over time, which complicates the calculation of the parameters of pipeline transportation. The article suggests a method of determining the initial parameters of such mixtures: the status coefficient, indicator of transportability, coefficient of hydrodynamic resistance to motion of the mixture. These indicators characterize the mixture in terms of the possibility to transport it through pipes. On the basis of these indicators is proposed methodology for calculating the parameters of pipeline transport hardening filling mixtures in drift mode when traffic on the horizontal part of the mixture under pressure column of the mixture in the vertical part of the backfill of the pipeline. This technique allows stable operation is guaranteed to provide pipeline transportation.

  15. Filling behaviour of wood plastic composites

    Science.gov (United States)

    Duretek, I.; Lucyshyn, T.; Holzer, C.

    2017-01-01

    Wood plastic composites (WPC) are a young generation of composites with rapidly growing usage within the plastics industry. The advantages are the availability and low price of the wood particles, the possibility of partially substituting the polymer in the mixture and sustainable use of the earth’s resources. The current WPC products on the market are to a large extent limited to extruded products. Nowadays there is a great interest in the market for consumer products in more use of WPC as an alternative to pure thermoplastics in injection moulding processes. This work presents the results of numerical simulation and experimental visualisation of the mould filling process in injection moulding of WPC. The 3D injection moulding simulations were done with the commercial software package Autodesk® Moldflow® Insight 2016 (AMI). The mould filling experiments were conducted with a box-shaped test part. In contrast to unfilled polymers the WPC has reduced melt elasticity so that the fountain flow often does not develop. This results in irregular flow front shapes in the moulded part, especially at high filler content.

  16. Voltammetric behavior and determination of the macrolide antibiotics azithromycin, clarithromycin and roxithromycin at a renewable silver – amalgam film electrode

    International Nuclear Information System (INIS)

    Vajdle, Olga; Guzsvány, Valéria; Škorić, Dušan; Csanádi, János; Petković, Miloš; Avramov-Ivić, Milka; Kónya, Zoltán; Petrović, Slobodan

    2017-01-01

    Highlights: • Voltammetric characterization of AZI, CLA and ROX at Hg(Ag)FE was performed. • AZI, CLA and ROX were determined via optimized SWV and SW-AdSV procedures. • Protonated forms of AZI, CLA and ROX favored their adsorption on Hg(Ag)FE. • 1 H NMR chemical shift dependence of N-methyl proton signals from pH. • Optimized SW-AdSV procedure was applied to determine ROX in Runac ® tablet. - Abstract: The renewable silver-amalgam film electrode (Hg(Ag)FE) was applied for voltammetric characterization and determination of semi-synthetic macrolide antibiotics azithromycin (AZI), clarithromycin (CLA) and roxithromycin (ROX) in the Britton-Robinson buffer as supporting electrolyte ranging the pH from 4.0 to 11.9. All three macrolides showed reduction signals in fairly negative potential range. During direct cathodic square wave voltammetric (SWV) investigations conducted over the potential range from −0.75 V to −2.00 V vs SCE, either one or two reduction peaks were obtained in the potential range from −1.5 to −1.9 V. The shapes and intensities of the signals depend on the applied pH values in wider pH ranges. For analytical purposes concerning the development of direct cathodic SWV and adsorptive stripping SWV (SW-AdSV) methods the neutral and slightly alkaline media were suitable as pH 7.2, pH 7.4 and pH 7.0 for AZI, CLA and ROX, respectively. Based on the cyclic voltammograms recorded at these pH values, adsorption-controlled electrode kinetics process can be proposed for all three macrolides. Furthermore, the water suppressed 1 H NMR measurements in the pH range between 6.0 and 10.5 indicated that the macrolide molecules at the optimal analytical conditions are predominantly in protonated form via their tertiary amino groups which supported in all three cases their adsorption on the appropriately polarized Hg(Ag)FE electrode. The optimized direct cathodic SWV methods showed good linearity in concentration ranges 4.81–23.3 μg mL −1 , 1.96

  17. Processes of arroyo filling in northern New Mexico, USA

    Science.gov (United States)

    Friedman, Jonathan M.; Vincent, Kirk R.; Griffin, Eleanor R.; Scott, Michael L.; Shafroth, Patrick B.; Auble, Gregor T.

    2015-01-01

    We documented arroyo evolution at the tree, trench, and arroyo scales along the lower Rio Puerco and Chaco Wash in northern New Mexico, USA. We excavated 29 buried living woody plants and used burial signatures in their annual rings to date stratigraphy in four trenches across the arroyos. Then, we reconstructed the history of arroyo evolution by combining trench data with arroyo-scale information from aerial imagery, light detection and ranging (LiDAR), longitudinal profiles, and repeat surveys of cross sections. Burial signatures in annual rings of salt cedar and willow dated sedimentary beds greater than 30 cm thick with annual precision. Along both arroyos, incision occurred until the 1930s in association with extreme high flows, and subsequent filling involved vegetation development, channel narrowing, increased sinuosity, and finally vertical aggradation. A strongly depositional sediment transport regime interacted with floodplain shrubs to produce a characteristic narrow, trapezoidal channel. The 55 km study reach along the Rio Puerco demonstrated upstream progression of arroyo widening and filling, but not of arroyo incision, channel narrowing, or floodplain vegetation development. We conclude that the occurrence of upstream progression within large basins like the Rio Puerco makes precise synchrony across basins impossible. Arroyo wall retreat is now mostly limited to locations where meanders impinge on the arroyo wall, forming hairpin bends, for which entry to and exit from the wall are stationary. Average annual sediment storage within the Rio Puerco study reach between 1955 and 2005 was 4.8 × 105 t/yr, 16% of the average annual suspended sediment yield, and 24% of the long-term bedrock denudation rate. At this rate, the arroyo would fill in 310 yr.

  18. Antimicrobial activity of different filling pastes for deciduous tooth treatment

    Directory of Open Access Journals (Sweden)

    Bruna Feltrin ANTONIAZZI

    2015-01-01

    Full Text Available Guedes-Pinto paste is the filling material most employed in Brazil for endodontic treatment of deciduous teeth; however, the Rifocort® ointment has been removed. Thus, the aim of this study was to investigate the antimicrobial potential of filling pastes, by proposing three new pharmacological associations to replace Rifocort® ointment with drugs of already established antimicrobial power: Nebacetin® ointment, 2% Chlorhexidine Gluconate gel, and Maxitrol® ointment. A paste composed of Iodoform, Rifocort® ointment and Camphorated Paramonochlorophenol (CPC was employed as the gold standard (G1. The other associations were: Iodoform, Nebacetin® ointment and CPC (G2; Iodoform, 2% Chlorhexidine Digluconate gel and CPC (G3; Iodoform, Maxitrol® ointment and CPC (G4. The associations were tested for Staphylococcus aureus (S. aureus, Streptococcus mutans (S. mutans, Streptococcus oralis (S. oralis, Enterococcus faecalis (E. faecalis, Escherichia coli (E. coli, and Bacillus subtilis (B. subtilis, using the methods of dilution on solid medium – orifice agar – and broth dilution. The results were tested using statistical analysis ANOVA and Kruskal-Wallis. They showed that all the pastes had a bacteriostatic effect on all the microorganisms, without any statistically significant difference, compared with G1. S. aureus was statistically significant (multiple comparison test of Tukey, insofar as G2 and G3 presented the worst and the best performance, respectively. All associations were bactericidal for E. coli, S. aureus, S. mutans and S. oralis. Only G3 and G4 were bactericidal for E. faecalis, whereas no product was bactericidal for B. subtilis. Thus, the tested pastes have antimicrobial potential and have proved acceptable for endodontic treatment of primary teeth.

  19. Physico-mechanical characteristics of commercially available bulk-fill composites.

    Science.gov (United States)

    Leprince, Julian G; Palin, William M; Vanacker, Julie; Sabbagh, Joseph; Devaux, Jacques; Leloup, Gaetane

    2014-08-01

    Bulk-fill composites have emerged, arguably, as a new "class" of resin-based composites, which are claimed to enable restoration in thick layers, up to 4mm. The objective of this work was to compare, under optimal curing conditions, the physico-mechanical properties of most currently available bulk-fill composites to those of two conventional composite materials chosen as references, one highly filled and one flowable "nano-hybrid" composite. Tetric EvoCeram Bulk Fill (Ivoclar-Vivadent), Venus Bulk Fill (Heraeus-Kulzer), SDR (Dentsply), X-tra Fil (VOCO), X-tra Base (VOCO), Sonic Fill (Kerr), Filtek Bulk Fill (3M-Espe), Xenius (GC) were compared to the two reference materials. The materials were light-cured for 40s in a 2mm×2mm×25mm Teflon mould. Degree of conversion was measured by Raman spectroscopy, Elastic modulus and flexural strength were evaluated by three point bending, surface hardness using Vickers microindentation before and after 24h ethanol storage, and filler weight content by thermogravimetric analysis. The ratio of surface hardness before and after ethanol storage was considered as an evaluation of polymer softening. Data were analyzed by one-way ANOVA and post hoc Tukey's test (p=0.05). The mechanical properties of the bulk-fill composites were mostly lower compared with the conventional high viscosity material, and, at best, comparable to the conventional flowable composite. Linear correlations of the mechanical properties investigated were poor with degree of conversion (0.090.8). Softening in ethanol revealed differences in polymer network density between material types. The reduction of time and improvement of convenience associated with bulk-fill materials is a clear advantage of this particular material class. However, a compromise with mechanical properties compared with more conventional commercially-available nano-hybrid materials was demonstrated by the present work. Given the lower mechanical properties of most bulk-fill materials

  20. 21 CFR 872.3310 - Coating material for resin fillings.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Coating material for resin fillings. 872.3310... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3310 Coating material for resin fillings. (a) Identification. A coating material for resin fillings is a device intended to be applied to the...

  1. 46 CFR 98.25-65 - Filling density.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Filling density. 98.25-65 Section 98.25-65 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS SPECIAL... § 98.25-65 Filling density. (a) The filling density, or the percent ratio of the liquefied gas that may...

  2. 21 CFR 872.3820 - Root canal filling resin.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Root canal filling resin. 872.3820 Section 872...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3820 Root canal filling resin. (a) Identification. A root canal filling resin is a device composed of material, such as methylmethacrylate, intended...

  3. 46 CFR 98.25-50 - Filling and discharge pipes.

    Science.gov (United States)

    2010-10-01

    ... with a secondary remote control of a type acceptable to the Commandant. (c) The excess flow, internal... 46 Shipping 4 2010-10-01 2010-10-01 false Filling and discharge pipes. 98.25-50 Section 98.25-50... § 98.25-50 Filling and discharge pipes. (a) Filling connections shall be provided with one of the...

  4. Feast to famine: Sediment supply control on Laramide basin fill

    Science.gov (United States)

    Carroll, Alan R.; Chetel, Lauren M.; Elliot Smith, M.

    2006-03-01

    Erosion of Laramide-style uplifts in the western United States exerted an important first-order influence on Paleogene sedimentation by controlling sediment supply rates to adjacent closed basins. During the latest Cretaceous through Paleocene, these uplifts exposed thick intervals of mud-rich Upper Cretaceous foreland basin fill, which was quickly eroded and redeposited. Cretaceous sedimentary lithologies dominate Paleocene conglomerate clast compositions, and the volume of eroded foreland basin strata is approximately twice the volume of preserved Paleocene basin fill. As a result of this sediment oversupply, clastic alluvial and paludal facies dominate Paleocene strata, and are associated with relatively shallow and ephemeral freshwater lake facies. In contrast, large, long-lived, carbonate-producing lakes occupied several of the basins during the Eocene. Basement-derived clasts (granite, quartzite, and other metamorphic rocks) simultaneously became abundant in lower Eocene conglomerate. We propose that Eocene lakes developed primarily due to exposure of erosion-resistant lithologies within cores of Laramide uplifts. The resultant decrease in erosion rate starved adjacent basins of sediment, allowing the widespread and prolonged deposition of organic-rich lacustrine mudstone. These observations suggest that geomorphic evolution of the surrounding landscape should be considered as a potentially important influence on sedimentation in many other interior basins, in addition to more conventionally interpreted tectonic and climatic controls.

  5. Colloid transport in model fracture filling materials

    Science.gov (United States)

    Wold, S.; Garcia-Garcia, S.; Jonsson, M.

    2010-12-01

    Colloid transport in model fracture filling materials Susanna Wold*, Sandra García-García and Mats Jonsson KTH Chemical Science and Engineering Royal Institute of Technology, SE-100 44 Stockholm, Sweden *Corresponding author: E-mail: wold@kth.se Phone: +46 8 790 6295 In colloid transport in water-bearing fractures, the retardation depends on interactions with the fracture surface by sorption or filtration. These mechanisms are difficult to separate. A rougher surface will give a larger area available for sorption, and also when a particle is physically hindered, it approaches the surface and enables further sorption. Sorption can be explained by electrostatics were the strongest sorption on minerals always is observed at pH below pHpzc (Filby et al., 2008). The adhesion of colloids to mineral surfaces is related to the surface roughness according to a recent study (Darbha et al., 2010). There is a large variation in the characteristics of water-bearing fractures in bedrock in terms of aperture distribution, flow velocity, surface roughness, mineral distributions, presence of fracture filling material, and biological and organic material, which is hard to implement in modeling. The aim of this work was to study the transport of negatively charged colloids in model fracture filling material in relation to flow, porosity, mineral type, colloid size, and surface charge distribution. In addition, the impact on transport of colloids of mixing model fracture filling materials with different retention and immobilization capacities, determined by batch sorption experiments, was investigated. The transport of Na-montmorillonite colloids and well-defined negatively charged latex microspheres of 50, 100, and 200 nm diameter were studied in either columns containing quartz or quartz mixed with biotite. The ionic strength in the solution was exclusively 0.001 and pH 6 or 8.5. The flow rates used were 0.002, 0.03, and 0.6 mL min-1. Sorption of the colloids on the model fracture

  6. Filling bore-holes with explosive

    Energy Technology Data Exchange (ETDEWEB)

    Alfredsson, S H

    1965-03-02

    In this device for filling boreholes formed in a rock formation with particulate explosive, the explosive is conveyed into the hole by means of a pressure fluid through a tube which has a lesser diameter than the hole. The tube is characterized by a lattice work arranged externally on it, and having a structure adapted to allow passage of a pressure fluid returning between the tube and the wall of the hole, but retaining particles of explosive entrained by the returning pressure fluid. In another arrangement of the device, the lattice work has the form of a brush, including filaments or bristles which are dimensioned to bridge the spacing between the tube and the wall of the hole. (12 claims)

  7. Alleviate Cellular Congestion Through Opportunistic Trough Filling

    Directory of Open Access Journals (Sweden)

    Yichuan Wang

    2014-04-01

    Full Text Available The demand for cellular data service has been skyrocketing since the debut of data-intensive smart phones and touchpads. However, not all data are created equal. Many popular applications on mobile devices, such as email synchronization and social network updates, are delay tolerant. In addition, cellular load varies significantly in both large and small time scales. To alleviate network congestion and improve network performance, we present a set of opportunistic trough filling schemes that leverage the time-variation of network congestion and delay-tolerance of certain traffic in this paper. We consider average delay, deadline, and clearance time as the performance metrics. Simulation results show promising performance improvement over the standard schemes. The work shed lights on addressing the pressing issue of cellular overload.

  8. Internal Accident Report: fill it out!

    CERN Multimedia

    2012-01-01

    It is important to report all accidents, near-misses and dangerous situations so that they can be avoided in the future.   Reporting these events allows the relevant services to take appropriate action and implement corrective and preventive measures. It should be noted that the routing of the internal accident report was recently changed to make sure that the people who need to know are informed. Without information, corrective action is not possible. Without corrective action, there is a risk that the events will recur. As soon as you experience or see something amiss, fill out an internal accident report! If you have any questions the HSE Unit will be happy to answer them. Contact us at safety-general@cern.ch. The HSE Unit

  9. Neutron transmission measurements on hydrogen filled microspheres

    International Nuclear Information System (INIS)

    Dyrnjaja, Eva; Hummel, Stefan; Keding, Marcus; Smolle, Marie-Theres; Gerger, Joachim; Zawisky, Michael

    2014-01-01

    Hollow microspheres are promising candidates for future hydrogen storage technologies. Although the physical process for hydrogen diffusion through glass is well understood, measurements of static quantities (e.q. hydrogen pressure inside the spheres) as well as dynamic properties (e.g. diffusion rate of hydrogen through glass) are still difficult to handle due to the small size of the spheres (d≈15μm). For diffusion rate measurements, the long-term stability of the experiment is also mandatory due to the relatively slow diffusion rate. In this work, we present an accurate and long-term stable measurement technique for static and dynamic properties, using neutron radiography. Furthermore, possible applications for hydrogen filled microspheres within the scope of radiation issues are discussed

  10. Direct contra naïve-indirect comparison of clinical failure rates between high-viscosity GIC and conventional amalgam restorations: an empirical study.

    Science.gov (United States)

    Mickenautsch, Steffen; Yengopal, Veerasamy

    2013-01-01

    Naïve-indirect comparisons are comparisons between competing clinical interventions' evidence from separate (uncontrolled) trials. Direct comparisons are comparisons within randomised control trials (RCTs). The objective of this empirical study is to test the null-hypothesis that trends and performance differences inferred from naïve-indirect comparisons and from direct comparisons/RCTs regarding the failure rates of amalgam and direct high-viscosity glass-ionomer cement (HVGIC) restorations in permanent posterior teeth have similar direction and magnitude. A total of 896 citations were identified through systematic literature search. From these, ten and two uncontrolled clinical longitudinal studies for HVGIC and amalgam, respectively, were included for naïve-indirect comparison and could be matched with three out twenty RCTs. Summary effects sizes were computed as Odds ratios (OR; 95% Confidence intervals) and compared with those from RCTs. Trend directions were inferred from 95% Confidence interval overlaps and direction of point estimates; magnitudes of performance differences were inferred from the median point estimates (OR) with 25% and 75% percentile range, for both types of comparison. Mann-Whitney U test was applied to test for statistically significant differences between point estimates of both comparison types. Trends and performance differences inferred from naïve-indirect comparison based on evidence from uncontrolled clinical longitudinal studies and from direct comparisons based on RCT evidence are not the same. The distributions of the point estimates differed significantly for both comparison types (Mann-Whitney U  =  25, n(indirect)  =  26; n(direct)  =  8; p  =  0.0013, two-tailed). The null-hypothesis was rejected. Trends and performance differences inferred from either comparison between HVGIC and amalgam restorations failure rates in permanent posterior teeth are not the same. It is recommended that clinical practice

  11. The order and volume fill rates in inventory control systems

    DEFF Research Database (Denmark)

    Thorstenson, Anders; Larsen, Christian

    2011-01-01

    This paper differentiates between an order (line) fill rate and a volume fill rate and specifies their performance for different inventory control systems. When the focus is on filling complete customer orders rather than total quantities the order fill rate would be the preferred service level...... measure. The main result shows how the order and volume fill rates are related in magnitude. Earlier results derived for a single-item, single-stage, continuous review inventory system with backordering and constant lead times controlled by a base-stock policy are extended in different directions...

  12. Traces: making sense of urodynamics testing--Part 8: Evaluating sensations of bladder filling.

    Science.gov (United States)

    Gray, Mikel

    2011-01-01

    The "Traces" series discusses how the urodynamic clinician generates usable data from a filling cystometrogram (CMG). Part 8 focuses on the question, "What are the sensations of bladder filling?" Recent research suggests that sensations of bladder filling wax and wane from consciousness in healthy persons free of bothersome lower urinary tract symptoms. Because of its invasive and atypical nature when compared to daily life, multichannel urodynamics testing cannot reproduce the numerous and complex variables that influence bladder sensation in the healthy individual, making the evaluation of sensations of bladder filling a particularly challenging component of the filling CMG. Routine assessment of bladder sensations focuses on identification of three landmarks--first sensation of bladder filling, first desire to void, and a strong desire to void. A fourth sensation, bladder fullness or a compelling desire to void, is recommended. In addition to assessing these sensations, the urodynamic clinician must assess sensations indicating associated disease or disorders affecting lower urinary tract function, including urgency, pain, and atypical sensations. This assessment should be completed in the context of the results of one or more validated instruments used to measure bladder sensations.

  13. Thermal-fluid analysis of the fill and drain operations of a cryrogenic fuel tank

    Science.gov (United States)

    Stephens, Craig A.; Hanna, Gregory J.; Gong, Leslie

    1993-01-01

    The Generic Research Cryogenic Tank was designed to establish techniques for testing and analyzing the behavior of reusable fuel tank structures subjected to cryogenic fuels and aerodynamic heating. The Generic Research Cryogenic Tank tests will consist of filling a pressure vessel to a prescribed fill level, waiting for steady-state conditions, then draining the liquid while heating the external surface to simulate the thermal environment associated with hypersonic flight. Initial tests of the Generic Research Cryogenic Tank will use liquid nitrogen with future tests requiring liquid hydrogen. Two-dimensional finite-difference thermal-fluid models were developed for analyzing the behavior of the Generic Research Cryogenic Tank during fill and drain operations. The development and results of the two-dimensional fill and drain models, using liquid nitrogen, are provided, along with results and discussion on extrapolating the model results to the operation of the full-size Generic Research Cryogenic Tank. These numerical models provided a means to predict the behavior of the Generic Research Cryogenic Tank during testing and to define the requirements for the Generic Research Cryogenic Tank support systems such as vent, drain, pressurization, and instrumentation systems. In addition, the fill model provided insight into the unexpected role of circumferential conduction in cooling the Generic Research Cryogenic Tank pressure vessel during fill operations.

  14. Direct observation of Medicaid beneficiary attempts to fill prescriptions for nicotine replacement medications.

    Science.gov (United States)

    Richter, Kimber P; Shergina, Elena; Grodie, Amanda; Massey, Justin K; Ellerbeck, Edward F; Applegate, Amanda; Faseru, Babalola

    2018-04-21

    Although many states have expanded Medicaid coverage of cessation medications, utilization remains low. Anecdotal reports suggest that beneficiaries are at times denied coverage of cessation medications at the pharmacy counter. We conducted an observational community-wide case study of Medicaid beneficiary attempts to fill over-the-counter nicotine replacement therapy at pharmacies. We recruited tobacco-using beneficiaries from a Federally Qualified Health Center, whose providers wrote paper prescriptions for nicotine patches. Study staff escorted beneficiaries to all eligible pharmacies (n = 18) in a Midwestern community to observe fill attempts. Study staff recorded encounters via smartphone into a secure database on a university server. Seven of 18 pharmacies (39%) did not fill the prescription on the day of the attempt. Of these, 6 offered to order the patch for pick-up at a later date. All (4/4) chain pharmacies filled the prescription; 2/3 mass merchant pharmacies failed to fill. Combining successful same-day fills with offers to order for pick-up, 17/18 (94%) would ultimately have been able to obtain patches. This pilot study found that many beneficiaries left pharmacies without a prescription in hand. Successful same-day fills varied markedly by store type. For people with low incomes, transportation presents a major barrier for delayed pick-up. In addition, delays can fuel ambivalence toward quitting. Future research based on this pilot study might address whether patients who fail to secure a same-day prescription ever fill the prescription and, if not, the degree to which this barrier contributes to success or failure in quitting. Copyright © 2018 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  15. Gap filling of 3-D microvascular networks by tensor voting.

    Science.gov (United States)

    Risser, L; Plouraboue, F; Descombes, X

    2008-05-01

    We present a new algorithm which merges discontinuities in 3-D images of tubular structures presenting undesirable gaps. The application of the proposed method is mainly associated to large 3-D images of microvascular networks. In order to recover the real network topology, we need to fill the gaps between the closest discontinuous vessels. The algorithm presented in this paper aims at achieving this goal. This algorithm is based on the skeletonization of the segmented network followed by a tensor voting method. It permits to merge the most common kinds of discontinuities found in microvascular networks. It is robust, easy to use, and relatively fast. The microvascular network images were obtained using synchrotron tomography imaging at the European Synchrotron Radiation Facility. These images exhibit samples of intracortical networks. Representative results are illustrated.

  16. Rock mechanics applied to cut and fill mining in Australia

    Energy Technology Data Exchange (ETDEWEB)

    Willoughby, D. R.

    1980-05-15

    Cut and fill mining and recent changes made possible by the application of rock mechanics principles are briefly introduced. The principal interests of professional groups associated with the industry, and incentives that exist to encourage research of benefit to the industry in general, are identified. Details are given of recent advances in rock mechanics instrumentation and technique by drawing to a large extent on experience gained in projects that have been conducted jointly with the mining companies. Examples of the application of the results of this research are given on a mine site basis. Reference is made where possible to papers that describe the examples in more detail. The review is concluded with identification of topics that require further research.

  17. Carpel size, grain filling, and morphology determine individual grain weight in wheat.

    Science.gov (United States)

    Xie, Quan; Mayes, Sean; Sparkes, Debbie L

    2015-11-01

    Individual grain weight is a major yield component in wheat. To provide a comprehensive understanding of grain weight determination, the carpel size at anthesis, grain dry matter accumulation, grain water uptake and loss, grain morphological expansion, and final grain weight at different positions within spikelets were investigated in a recombinant inbred line mapping population of bread wheat (Triticum aestivum L.)×spelt (Triticum spelta L.). Carpel size, grain dry matter and water accumulation, and grain dimensions interacted strongly with each other. Furthermore, larger carpels, a faster grain filling rate, earlier and longer grain filling, more grain water, faster grain water absorption and loss rates, and larger grain dimensions were associated with higher grain weight. Frequent quantitative trait locus (QTL) coincidences between these traits were observed, particularly those on chromosomes 2A, 3B, 4A, 5A, 5DL, and 7B, each of which harboured 16-49 QTLs associated with >12 traits. Analysis of the allelic effects of coincident QTLs confirmed their physiological relationships, indicating that the complex but orderly grain filling processes result mainly from pleiotropy or the tight linkages of functionally related genes. After grain filling, distal grains within spikelets were smaller than basal grains, primarily due to later grain filling and a slower initial grain filling rate, followed by synchronous maturation among different grains. Distal grain weight was improved by increased assimilate availability from anthesis. These findings provide deeper insight into grain weight determination in wheat, and the high level of QTL coincidences allows simultaneous improvement of multiple grain filling traits in breeding. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  18. Filled aperture concepts for the Terrestrial Planet Finder

    Science.gov (United States)

    Ridgway, Stephen T.

    2003-02-01

    Filled aperture telescopes can deliver a real, high Strehl image which is well suited for discrimination of faint planets in the vicinity of bright stars and against an extended exo-zodiacal light. A filled aperture offers a rich variety of PSF control and diffraction suppression techniques. Filled apertures are under consideration for a wide spectral range, including visible and thermal-IR, each of which offers a significant selection of biomarker molecular bands. A filled aperture visible TPF may be simpler in several respects than a thermal-IR nuller. The required aperture size (or baseline) is much smaller, and no cryogenic systems are required. A filled aperture TPF would look and act like a normal telescope - vendors and users alike would be comfortable with its design and operation. Filled aperture telescopes pose significant challenges in production of large primary mirrors, and in very stringent wavefront requirements. Stability of the wavefront control, and hence of the PSF, is a major issue for filled aperture systems. Several groups have concluded that these and other issues can be resolved, and that filled aperture options are competitive for a TPF precursor and/or for the full TPF mission. Ball, Boeing-SVS and TRW have recently returned architecture reviews on filled aperture TPF concepts. In this paper, I will review some of the major considerations underlying these filled aperture concepts, and suggest key issues in a TPF Buyers Guide.

  19. Surface Patterning Using Diazonium Ink Filled Nanopipette.

    Science.gov (United States)

    Zhou, Min; Yu, Yun; Blanchard, Pierre-Yves; Mirkin, Michael V

    2015-11-03

    Molecular grafting of diazonium is a widely employed surface modification technique. Local electrografting of this species is a promising approach to surface doping and related properties tailoring. The instability of diazonium cation complicates this process, so that this species was generated in situ in many reported studies. In this Article, we report the egress transfer of aryl diazonium cation across the liquid/liquid interface supported at the nanopipette tip that can be used for controlled delivery this species to the external aqueous phase for local substrate patterning. An aryl diazonium salt was prepared with weakly coordinating and lipophilic tetrakis(pentafluorophenyl)borate anion stable as a solid and soluble in low polarity media. The chemically stable solution of this salt in 1,2-dichloroethane can be used as "diazonium ink". The ink-filled nanopipette was employed as a tip in the scanning electrochemical microscope (SECM) for surface patterning with the spatial resolution controlled by the pipette orifice radius and a few nanometers film thickness. The submicrometer-size grafted spots produced on the HOPG surface were located and imaged with the atomic force microscope (AFM).

  20. Polymer deformation and filling modes during microembossing

    Science.gov (United States)

    Rowland, Harry D.; King, William P.

    2004-12-01

    This work investigates the initial stages of polymer deformation during hot embossing micro-manufacturing at processing temperatures near the glass transition temperature (Tg) of polymer films having sufficient thickness such that polymer flow is not supply limited. Several stages of polymer flow can be observed by employing stamp geometries of various widths and varying imprint conditions of time and temperature to modulate polymer viscosity. Experiments investigate conditions affecting cavity filling phenomena, including apparent polymer viscosity. Stamps with periodic ridges of height and width 4 µm and periodicity 30, 50 and 100 µm emboss trenches into polymethyl methacrylate films at Tg - 10 °C time, temperature and load are correlated with replicated polymer shape, height and imprinted area. Polymer replicates are measured by atomic force microscopy and inspected by scanning electron microscopy. Cavity size and the temperature dependence of polymer viscosity significantly influence the nature of polymer deformation in hot embossing micro-manufacturing and must be accounted for in rational process design.

  1. Turbulent flow in a partially filled pipe

    Science.gov (United States)

    Ng, Henry; Cregan, Hope; Dodds, Jonathan; Poole, Robert; Dennis, David

    2017-11-01

    Turbulent flow in a pressure driven pipe running partially full has been investigated using high-speed 2D-3C Stereoscopic Particle Imaging Velocimetry. With the field-of-view spanning the entire pipe cross section we are able to reconstruct the full three dimensional quasi-instantaneous flow field by invoking Taylor's hypothesis. The measurements were carried out over a range of flow depths at a constant Reynolds number based on hydraulic diameter and bulk velocity of Re = 32 , 000 . In agreement with previous studies, the ``velocity dip'' phenomenon, whereby the location of the maximum streamwise velocity occurs below the free surface was observed. A mean flow secondary current is observed near the free surface with each of the counter-rotating rollers filling the half-width of the pipe. Unlike fully turbulent flow in a rectangular open channel or pressurized square duct flow where the secondary flow cells appear in pairs about a corner bisector, the mean secondary motion observed here manifests only as a single pair of vortices mirrored about the pipe vertical centreline.

  2. Thermodynamics of the amalgam cells {l_brace}Cs-amalgam|CsX (m)|AgX|Ag{r_brace} (X=Cl, Br, I) and primary medium effects in (methanol+water) (acetonitrile+water), and (1,4-dioxane+water) solvent mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Falciola, Luigi [Department of Physical Chemistry and Electrochemistry, University of Milan, Via Golgi 19, I-20133 Milan (Italy)]. E-mail: luigi.falciola@unimi.it; Longoni, Giorgio [Department of Physical Chemistry and Electrochemistry, University of Milan, Via Golgi 19, I-20133 Milan (Italy); Mussini, Patrizia R. [Department of Physical Chemistry and Electrochemistry, University of Milan, Via Golgi 19, I-20133 Milan (Italy)]. E-mail: patrizia.mussini@unimi.it; Mussini, Torquato [Department of Physical Chemistry and Electrochemistry, University of Milan, Via Golgi 19, I-20133 Milan (Italy)]. E-mail: torquato.mussini@unimi.it

    2006-06-15

    The potential difference E of the amalgam cell {l_brace}Cs{sub x}Hg{sub 1-x}|CsX (m)|AgX|Ag{r_brace} (X=Cl, Br, I) has been measured as a function of the mole fraction x{sub Cs} of Cs metal in amalgams and of the molality m of CsX in (methanol+water) (acetonitrile+water), and (1,4-dioxane+water) solvent mixtures containing up to 0.75 mass fraction of the organic component, at the temperature 298.15K. The respective standard molal potential differences E{sub m}{sup o} have been determined together with the relevant activity coefficients {gamma}{sub +}/- as functions of the CsX molality. The found E{sub m}{sup o} values show a parabolic decrease with increasing proportion of the organic component in the solvent mixture. Analysis of the relevant primary medium effects upon CsX shows that the CsX transfer from the standard state in water to the standard state in the (aqueous+organic) mixture is always unfavoured, and the acetonitrile is the least unfavoured co-solvent studied. Analysis of the primary medium effect upon CsI in terms of Feakins and French's theory leads to a primary hydration number close to zero, which is consistent with the results of supplementary EXAFS experiments on Cs{sup +} and I{sup -} in (acetonitrile+water) solvent mixtures.

  3. Sorption of Np (Ⅴ) on Beishan granite fracture filling materials

    International Nuclear Information System (INIS)

    Jiang Tao; Wang Bo; Bao Liangjin; Zhou Duo; Long Haoqi; Song Zhixin; Chen Xi

    2012-01-01

    The sorption behaviors of Np (Ⅴ) on the granite fracture filling materials were studied by batch experiments under anaerobic in Beishan groundwater. The impact of pH of groundwater, CO 3 2- , humic acid and different components of granite fracture filling materials on sorption of Np (Ⅴ) was investigated. The results show that the granite fracture filling materials have strong capacity of Np (Ⅴ) adsorption. The value of K d , for Np (Ⅴ) sorption on the granite fracture filling materials is 843 mL/g. With the increase of pH, the value of K d increases at first and then decreases. K d of Np sorption on granite fracture filling materials in the presence of CO 3 2- and humic acid decreases. The chlorite and feldspar are major contributors to the sorption of Np (Ⅴ) on Beishan granite fracture filling materials. (authors)

  4. Effects of selective attention on perceptual filling-in.

    Science.gov (United States)

    De Weerd, P; Smith, E; Greenberg, P

    2006-03-01

    After few seconds, a figure steadily presented in peripheral vision becomes perceptually filled-in by its background, as if it "disappeared". We report that directing attention to the color, shape, or location of a figure increased the probability of perceiving filling-in compared to unattended figures, without modifying the time required for filling-in. This effect could be augmented by boosting attention. Furthermore, the frequency distribution of filling-in response times for attended figures could be predicted by multiplying the frequencies of response times for unattended figures with a constant. We propose that, after failure of figure-ground segregation, the neural interpolation processes that produce perceptual filling-in are enhanced in attended figure regions. As filling-in processes are involved in surface perception, the present study demonstrates that even very early visual processes are subject to modulation by cognitive factors.

  5. The order and volume fill rates in inventory control systems

    DEFF Research Database (Denmark)

    Thorstenson, Anders; Larsen, Christian

    2014-01-01

    This paper differentiates between an order (line) fill rate and a volume fill rate and specifies their performance for different inventory control systems. When the focus is on filling complete customer orders rather than total demanded quantity the order fill rate would be the preferred service...... level measure. The main result shows how the order and volume fill rates are related in magnitude. Earlier results derived for a single-item, single-stage, continuous review inventory system with backordering and constant lead times controlled by a base-stock policy are extended in different directions...... extensions consider more general inventory control review policies with backordering, as well as some relations between service measures. A particularly important result in the paper concerns an alternative service measure, the customer order fill rate, and shows how this measure always exceeds the other two...

  6. Curing characteristics of flowable and sculptable bulk-fill composites

    OpenAIRE

    Miletic, Vesna; Pongpruenska, Pong; De Munck, Jan; Brooks, Neil R; Van Meerbeek, Bart

    2016-01-01

    OBJECTIVES: The aim of this study was to determine and correlate the degree of conversion (DC) with Vickers hardness (VH) and translucency parameter (TP) with the depth of cure (DoC) of five bulk-fill composites. MATERIALS AND METHODS: Six specimens per group, consisting of Tetric EvoCeram Bulk Fill ("TEC Bulk," Ivoclar Vivadent), SonicFill (Kerr), SDR Smart Dentin Replacement ("SDR," Dentsply), Xenius base ("Xenius," StickTech; commercialized as EverX Posterior, GC), Filtek Bul...

  7. Bladder filling variation during conformal radiotherapy for rectal cancer

    International Nuclear Information System (INIS)

    Sithamparam, S; Ahmad, R; Sabarudin, A; Othman, Z; Ismail, M

    2017-01-01

    Conformal radiotherapy for rectal cancer is associated with small bowel toxicity mainly diarrhea. Treating patients with a full bladder is one of the practical solutions to reduce small bowel toxicity. Previous studies on prostate and cervix cancer patients revealed that maintaining consistent bladder volume throughout radiotherapy treatment is challenging. The aim of this study was to measure bladder volume variation throughout radiotherapy treatment. This study also measured the association between bladder volume changes and diarrhea. Twenty two rectal cancer patients were recruited prospectively. Patients were planned for treatment with full bladder following departmental bladder filling protocol and the planning bladder volume was measured during CT-simulation. During radiotherapy, the bladder volume was measured weekly using cone-beam computed tomography (CBCT) and compared to planning bladder volume. Incidence and severity of diarrhea were recorded during the weekly patient review. There was a negative time trend for bladder volume throughout five weeks treatment. The mean bladder volume decreased 18 % from 123 mL (SD 54 mL) during CT-simulation to 101 mL (SD 71 mL) on the 5th week of radiotherapy, but the decrease is not statistically significant. However, there was a large variation of bladder volume within each patient during treatment. This study showed an association between changes of bladder volume and diarrhea (P = 0.045). In conclusion bladder volume reduced throughout radiotherapy treatment for conformal radiotherapy for rectal cancer and there was a large variation of bladder volume within patients. (paper)

  8. Bladder filling variation during conformal radiotherapy for rectal cancer

    Science.gov (United States)

    Sithamparam, S.; Ahmad, R.; Sabarudin, A.; Othman, Z.; Ismail, M.

    2017-05-01

    Conformal radiotherapy for rectal cancer is associated with small bowel toxicity mainly diarrhea. Treating patients with a full bladder is one of the practical solutions to reduce small bowel toxicity. Previous studies on prostate and cervix cancer patients revealed that maintaining consistent bladder volume throughout radiotherapy treatment is challenging. The aim of this study was to measure bladder volume variation throughout radiotherapy treatment. This study also measured the association between bladder volume changes and diarrhea. Twenty two rectal cancer patients were recruited prospectively. Patients were planned for treatment with full bladder following departmental bladder filling protocol and the planning bladder volume was measured during CT-simulation. During radiotherapy, the bladder volume was measured weekly using cone-beam computed tomography (CBCT) and compared to planning bladder volume. Incidence and severity of diarrhea were recorded during the weekly patient review. There was a negative time trend for bladder volume throughout five weeks treatment. The mean bladder volume decreased 18 % from 123 mL (SD 54 mL) during CT-simulation to 101 mL (SD 71 mL) on the 5th week of radiotherapy, but the decrease is not statistically significant. However, there was a large variation of bladder volume within each patient during treatment. This study showed an association between changes of bladder volume and diarrhea (P = 0.045). In conclusion bladder volume reduced throughout radiotherapy treatment for conformal radiotherapy for rectal cancer and there was a large variation of bladder volume within patients.

  9. Prevalence of apical periodontitis and quality of root canal fillings in population of Zagreb, Croatia: a cross-sectional study

    Science.gov (United States)

    Matijević, Jurica; Čižmeković Dadić, Tina; Prpić Mehičić, Goranka; Anić, Ivica; Šlaj, Mladen; Jukić Krmek, Silvana

    2011-01-01

    Aim To determine the prevalence of apical periodontitis and assess the quality of endodontic fillings in the population of the city of Zagreb, Croatia. Methods A total of 1462 orthopantomograms from new patients at 6 different dental practices was analyzed during 2006 and 2007. The presence of periapical lesions was determined by using the periapical index score (PAI). The quality of endodontic fillings was assessed according to the filling length and homogeinicity. Data were analyzed using t test and ANOVA with Scheffe post-hoc test. Results There were 75.9% of participants with endodontically treated teeth and 8.5% of all teeth were endodontically treated. Only 34.2% of endodontically treated roots had adequate root canal filling length, while 36.2% of root canal fillings had homogenous appearance. From the total number of teeth with intracanal post, 17.5% had no visible root canal filling. Using PAI 3 as a threshold value for apical periodontitis, periapical lesions were detected in 8.5% of teeth. Adequate quality of root canal fillings was associated with a lower prevalence of periapical lesions. Conclusion We found a large proportion of endodontically treated teeth with apical periodontitis and a correlation between the quality of endodontic filling and the prevalence of periapical lesions. This all suggests that it is necessary to improve the quality of endodontic treatment in order to reduce the incidence and prevalence of apical periodontitis. PMID:22180266

  10. Method for automatic filling of nuclear fuel rod cladding tubes

    International Nuclear Information System (INIS)

    Bezold, H.

    1979-01-01

    Prior to welding the zirconium alloy cladding tubes with end caps, they are automatically filled with nuclear fuel tablets and ceramic insulating tablets. The tablets are introduced into magazine drums and led through a drying oven to a discharging station. The empty cladding tubes are removed from this discharging station and filled with tablets. A filling stamp pushes out the columns of tablets in the magazine tubes of the magazine drum into the cladding tube. Weight and measurement of length determine the filled state of the cladding tube. The cladding tubes are then led to the welding station via a conveyor belt. (DG) [de

  11. Initial settlements of rock fills on soft clay

    OpenAIRE

    Pedersen, Truls Martens

    2012-01-01

    Rock fills that hit the seabed will remold the underlying material. If this material is a clay with sufficiently low shear strength, it will adopt rheological properties, causing flow through the rock fill, and contributing to the initial settlements of the rock fill in addition to conventional consolidation theory. The settlements of the rocks depend upon the height of the rock fill and how the rocks have been laid out. This is due to the viscosity of the clay, and the fact that clay is thix...

  12. Reinforcing the inner phase of the filled hydrogels with CNTs alters drug release properties and human keratinocyte morphology: A study on the gelatin- tamarind gum filled hydrogels.

    Science.gov (United States)

    Maharana, Vivek; Gaur, Deepanjali; Nayak, Suraj K; Singh, Vinay K; Chakraborty, Subhabrata; Banerjee, Indranil; Ray, Sirsendu S; Anis, Arfat; Pal, Kunal

    2017-11-01

    The study reports the synthesis and characterization of gelatin-tamarind gum (TG) based filled hydrogels for drug delivery applications. In this study, three different types of carbon nanotubes (CNTs) were incorporated within the dispersed TG phase of the filled hydrogels. The prepared hydrogels were thoroughly characterised using bright field microscope, FESEM, FTIR spectroscopy, differential scanning calorimeter, and mechanical tester. The swelling and the drug (salicylic acid) release properties of the filled hydrogels were also evaluated. The micrographs revealed the formation of biphasic systems. The internal phase appeared as agglomerates, and the CNTs were confined within the dispersed TG phase. FTIR and XRD studies revealed that CNTs promoted associative interactions among the components of the hydrogel, which promoted the formation of large crystallite size. The mechanical study indicated better resistance to the breakdown of the architecture of the CNT-containing filled hydrogels. Drug release studies, both passive and iontophoretic, suggested that the non-Fickian diffusion of the drug was prevalent during its release from hydrogel matrices. The prepared hydrogels were cytocompatible with human keratinocytes. The results suggested the probable use of such hydrogels in wound healing, tissue engineering and drug delivery applications. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Increasing Polymer Solar Cell Fill Factor by Trap-Filling with F4-TCNQ at Parts Per Thousand Concentration.

    Science.gov (United States)

    Yan, Han; Manion, Joseph G; Yuan, Mingjian; García de Arquer, F Pelayo; McKeown, George R; Beaupré, Serge; Leclerc, Mario; Sargent, Edward H; Seferos, Dwight S

    2016-08-01

    Intrinsic traps in organic semiconductors can be eliminated by trap-filling with F4-TCNQ. Photovoltaic tests show that devices with F4-TCNQ at parts per thousand concentration outperform control devices due to an improved fill factor. Further studies confirm the trap-filling pathway and demonstrate the general nature of this finding. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Impact of valley fills on streamside salamanders in southern West Virginia

    Science.gov (United States)

    Wood, Petra Bohall; Williams, Jennifer M.

    2013-01-01

    Valley fills associated with mountaintop-removal mining bury stream headwaters and affect water quality and ecological function of reaches below fills. We quantified relative abundance of streamside salamanders in southern West Virginia during 2002 in three streams below valley fills (VFS) and in three reference streams (RS). We surveyed 36 10- × 2-m stream transects, once in summer and fall, paired by order and structure. Of 2,343 salamanders captured, 66.7% were from RS. Total salamanders (adults plus larvae) were more abundant in RS than VFS for first-order and second-order reaches. Adult salamanders had greater abundance in first-order reaches of RS than VFS. Larval salamanders were more abundant in second-order reaches of RS than VFS. No stream width or mesohabitat variables differed between VFS and RS. Only two cover variables differed. Silt cover, greater in VFS than RS first-order reaches, is a likely contributor to reduced abundance of salamanders in VFS. Second-order RS had more boulder cover than second-order VFS, which may have contributed to the higher total and larval salamander abundance in RS. Water chemistry assessments of our VFS and RS reported elevated levels of metal and ion concentrations in VFS, which can depress macroinvertebrate populations and likely affect salamander abundance. Valley fills appear to have significant negative effects on stream salamander abundance due to alterations in habitat structure, water quality and chemistry, and macroinvertebrate communities in streams below fills.

  15. COMSOL Multiphysics Model for HLW Canister Filling

    Energy Technology Data Exchange (ETDEWEB)

    Kesterson, M. R. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-04-11

    The U.S. Department of Energy (DOE) is building a Tank Waste Treatment and Immobilization Plant (WTP) at the Hanford Site in Washington to remediate 55 million gallons of radioactive waste that is being temporarily stored in 177 underground tanks. Efforts are being made to increase the loading of Hanford tank wastes in glass while meeting melter lifetime expectancies and process, regulatory, and product quality requirements. Wastes containing high concentrations of Al2O3 and Na2O can contribute to nepheline (generally NaAlSiO4) crystallization, which can sharply reduce the chemical durability of high level waste (HLW) glass. Nepheline crystallization can occur during slow cooling of the glass within the stainless steel canister. The purpose of this work was to develop a model that can be used to predict temperatures of the glass in a WTP HLW canister during filling and cooling. The intent of the model is to support scoping work in the laboratory. It is not intended to provide precise predictions of temperature profiles, but rather to provide a simplified representation of glass cooling profiles within a full scale, WTP HLW canister under various glass pouring rates. These data will be used to support laboratory studies for an improved understanding of the mechanisms of nepheline crystallization. The model was created using COMSOL Multiphysics, a commercially available software. The model results were compared to available experimental data, TRR-PLT-080, and were found to yield sufficient results for the scoping nature of the study. The simulated temperatures were within 60 ºC for the centerline, 0.0762m (3 inch) from centerline, and 0.2286m (9 inch) from centerline thermocouples once the thermocouples were covered with glass. The temperature difference between the experimental and simulated values reduced to 40 ºC, 4 hours after the thermocouple was covered, and down to 20 ºC, 6 hours after the thermocouple was covered

  16. Estimation of water-filled and air-filled porosity in the unsaturated zone, Yucca Mountain, Nevada

    International Nuclear Information System (INIS)

    Nelson, P.H.

    1993-01-01

    Water content and porosity vary considerably within the unsaturated zone at Yucca Mountain. Measurement of these quantities has been based on core samples. A log-based approach offers the advantage of in-situ measurements, continuous throughout the borehole. This paper describes an algorithm which determines the air-filled and water-filled porosities from density and dielectric logs. The responses of density and dielectric logs are formulated in terms of the matrix properties, air-filled porosity and water-filled porosity. Porosity values obtained from logs from borehole USW G-2 are in reasonable agreement with estimates from core determinations

  17. A case of mitochondrial cardiomyopathy with restrictive transmitral filling pattern

    Directory of Open Access Journals (Sweden)

    Otsui K

    2012-04-01

    Full Text Available Kazunori Otsui, Nobutaka Inoue, Anna Tamagawa, Kazuo OnishiDepartment of Cardiovascular Medicine, Kobe Rosai Hospital, Kobe, JapanAbstract: A 61-year-old diabetic woman with a mitochondrial A3243G mutation was hospitalized for evaluation of breathlessness, general fatigue, and leg edema. Chest radiography revealed cardiomegaly with massive pleural effusion. Serum lactate, pyruvate, and brain natriuretic peptide concentrations were elevated. Transthoracic echocardiography revealed a restrictive pattern of transmitral flow, although systolic function of the left ventricle was only mildly impaired. Based on these findings and her clinical course, the patient was diagnosed with right-sided heart failure caused by mitochondrial cardiomyopathy associated with a restrictive transmitral filling pattern. Treatment with furosemide, enalapril, and eplerenone was effective, and improvement in her symptoms was associated with amelioration of transthoracic echocardiographic findings and a reduction in serum brain natriuretic peptide levels. Previous reports have indicated heterogeneity in the clinical features of mitochondrial cardiomyopathy in patients carrying the A3243G mutation; the present case highlights the substantial variability in the clinical features of this disease.Keywords: mitochondrial disease, A3243G mutation, diastolic dysfunction, transmitral flow

  18. Using Habit Reversal to Decrease Filled Pauses in Public Speaking

    Science.gov (United States)

    Mancuso, Carolyn; Miltenberger, Raymond G.

    2016-01-01

    This study evaluated the effectiveness of simplified habit reversal in reducing filled pauses that occur during public speaking. Filled pauses consist of "uh," "um," or "er"; clicking sounds; and misuse of the word "like." After baseline, participants received habit reversal training that consisted of…

  19. Optimization of foam-filled bitubal structures for crashworthiness criteria

    International Nuclear Information System (INIS)

    Zhang, Yong; Sun, Guangyong; Li, Guangyao; Luo, Zhen; Li, Qing

    2012-01-01

    Highlights: ► The paper aims to optimize foam-filled bitubal squared column for crashworthiness. ► It explores different formulations and configurations of design. ► The optimal foam-filled bitubal column is better than foam-filled monotubal column. ► The optimal foam-filled bitubal column is better than empty bitubal column. -- Abstract: Thin-walled structures have been widely used as key components in automobile and aerospace industry to improve the crashworthiness and safety of vehicles while maintaining overall light-weight. This paper aims to explore the design issue of thin-walled bitubal column structures filled with aluminum foam. As a relatively new filler material, aluminum foam can increase crashworthiness without sacrificing too much weight. To optimize crashworthiness of the foam-filled bitubal square column, the Kriging meta-modeling technique is adopted herein to formulate the objective and constraint functions. The genetic algorithm (GA) and Non-dominated Sorting Genetic Algorithm II (NSGA II) are used to seek the optimal solutions to the single and multiobjective optimization problems, respectively. To compare with other thin-walled configurations, the design optimization is also conducted for empty bitubal column and foam-filled monotubal column. The results demonstrate that the foam-filled bitubal configuration has more room to enhance the crashworthiness and can be an efficient energy absorber.

  20. Theory Of Dewetting In A Filled Elastomer Under Stress

    Science.gov (United States)

    Peng, Steven T. J.

    1993-01-01

    Report presents theoretical study of dewetting between elastomeric binder and filler particles of highly filled elastomer under multiaxial tension and resulting dilatation of elastomer. Study directed toward understanding and predicting nonlinear stress-vs.-strain behavior of filled elastomeric rocket propellant, also applicable to rubber in highly loaded tire or in damping pad.

  1. Predicting heat transfer in long, R-134a filled thermosyphons

    NARCIS (Netherlands)

    Grooten, M.H.M.; Geld, van der C.W.M.

    2008-01-01

    When traditional air-to-air cooling is too voluminous, heat exchangers with long thermosyphons offer a good alternative. Experiments with a single thermosyphon with a large length-to-diameter ratio (188) and filled with R-134a are presented and analyzed. Saturation temperatures, filling ratios, and

  2. Radiodiagnosis of filled retention bronchial cysts and lung tuberculomes

    International Nuclear Information System (INIS)

    Gudz', A.E.

    1987-01-01

    Radiological semiotics of filled retention bronchial cysts in 23 patients and of lung tuberculomes in 52 is studied on the basis of the data on roentgenography, tomography and bronchography. Characteristic radiological signs of retention bronchial cysts and tuberculomes are determined. Significance of each radiological sign for differential diagnosis of filled retention bronchial cysts and lung tuberculomes is estimated

  3. CHARACTERISTICS OF FLORIDA FILL MATERIALS AND SOILS 1990

    Science.gov (United States)

    The report gives results of laboratory work by the University of Florida in support of the Foundation Fill Data Base project of the Foundation Fill Materials Specifications Task Area of the Florida Radon Research Program (FRRP). Work included determination of radon concentrations...

  4. Simulation of mould filling process for composite skeleton castings

    Directory of Open Access Journals (Sweden)

    M. Dziuba

    2008-04-01

    Full Text Available In this work authors showed selected results of simulation and experimental studies on temperature distribution during solidification of skeleton casting and mould filling process. The aim of conducted simulations was the choice of thermal and geometrical parameters for the needs of designed calculations of the skeleton castings and the estimation of the guidelines for the technology of manufacturing. The subject of numerical simulation was the analysis of ability of filling the channels of core by liquid metal at estability technological parameters.. Below the assumptions and results of the initial simulated calculations are presented. The total number of the nodes in the casting was 1920 and of the connectors was 5280 what gave filling of 100% for the nodes and 99,56% for the connectors in the results of the simulation. Together it resulted as 99,78 % of filling the volume of the casting. The nodes and connectors were filled up to the 30 level of the casting in the simulation. The all connectors were filled up to the 25 level of the casting in the simulation. Starting from the 25 level individual connectors at the side surface of the casting weren’t filled up. The connectors weren’t supplied by multi-level getting system. The differences of filling the levels are little (maximally 5 per cent.

  5. The automatic liquid nitrogen filling system for GDA detectors

    Indian Academy of Sciences (India)

    In addition, no physical access to the beam hall is required during routine filling operation. The system consists of ... PSI with the manual valve (MV) on the dewar kept open. For filling the detectors on one ... sequence the opening/closing of the valves depending upon the outlet temperature. By monitoring the time taken for ...

  6. Method and apparatus for filling cryogenic liquid cylinders

    International Nuclear Information System (INIS)

    Remes, S.

    1984-01-01

    A method and apparatus are disclosed for filling a portable cryogenic liquid cylinder from a large stand tank. The invention employs a regulator valve to perform an automatic throttling function whereby the pressure in the liquid cylinder is maintained at a value slightly lower than the upstream pressure in the stand tank. This significantly reduces filling losses due to flashing

  7. Gap filling strategies and error in estimating annual soil respiration

    Science.gov (United States)

    Soil respiration (Rsoil) is one of the largest CO2 fluxes in the global carbon (C) cycle. Estimation of annual Rsoil requires extrapolation of survey measurements or gap-filling of automated records to produce a complete time series. While many gap-filling methodologies have been employed, there is ...

  8. Rapid filling of pipelines with the SPH particle method

    NARCIS (Netherlands)

    Hou, Q.; Zhang, L.X.; Tijsseling, A.S.; Kruisbrink, A.C.H.

    2011-01-01

    The paper reports the development and application of a SPH (smoothed particle hydrodynamics) based simulation of rapid filling of pipelines, for which the rigid-column model is commonly used. In this paper the water-hammer equations with a moving boundary are used to model the pipe filling process,

  9. Rapid filling of pipelines with the SPH particle method

    NARCIS (Netherlands)

    Hou, Q.; Zhang, L.X.; Tijsseling, A.S.; Kruisbrink, A.C.H.

    2012-01-01

    The paper reports the development and application of a SPH (smoothed particle hydrodynamics) based simulation of rapid filling of pipelines, for which the rigid-column model is commonly used. In this paper the water-hammer equations with a moving boundary are used to model the pipe filling process,

  10. Process for automatic filling of nuclear fuel rod cans

    International Nuclear Information System (INIS)

    Bezold, H.

    1977-01-01

    A drying section is inserted in the production line for the automation of the filling process for fuel rods with nuclear fuel pellets. The pellets are taken in a drum magazine to a drying furnace and then pushed out one after the other into the can to be filled. (TK) [de

  11. 46 CFR 151.03-21 - Filling density.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Filling density. 151.03-21 Section 151.03-21 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES BARGES CARRYING BULK LIQUID HAZARDOUS MATERIAL CARGOES Definitions § 151.03-21 Filling density. The ratio, expressed as...

  12. Excavation/Fill/Soil Disturbance, Self-Study #31419

    Energy Technology Data Exchange (ETDEWEB)

    Grogin, Phillip W. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2018-02-06

    This course, Excavation/Fill/Soil Disturbance Self-Study (#31419), presents an overview of the hazards, controls, and requirements that affect safe excavations at Los Alamos National Laboratory (LANL). An overview of the LANL excavation/fill/soil disturbance permit (EXID permit) approval process is also presented, along with potholing requirements for planning and performing excavations at LANL.

  13. Microbiological studies on bacterial isolates from penicillins filling ...

    African Journals Online (AJOL)

    Aseptic processing is a critical method for the preparation of thermolabile sterile parenteral drug products. Sterile β-lactam antibiotics are extremely deactivated by heat, so the method of choice for their processing is through aseptic filling. The consequences of contamination on aseptically-filled products are harmful to the ...

  14. 27 CFR 4.72 - Metric standards of fill.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Metric standards of fill. 4.72 Section 4.72 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS LABELING AND ADVERTISING OF WINE Standards of Fill for Wine § 4.72 Metric...

  15. Introduction of a theoretical splashing degree to assess the performance of low-viscosity oils in filling of capsules.

    Science.gov (United States)

    Niederquell, Andreas; Kuentz, Martin

    2011-03-01

    These days an alternative to soft capsules is liquid-filled hard capsules. Their filling technology was investigated earlier with highly viscous formulations, while hardly any academic research focused on low-viscosity systems. Accordingly, this work addressed the filling of such oils that are splashing during the dosing process. It was aimed to first study capsule filling, using middle-chain triglycerides as reference oil, in order to then evaluate the concept of a new theoretical splashing degree for different oils. A laboratory-scale filling machine was used that included capsule sealing. Thus, the liquid encapsulation by microspray technology was employed to seal the dosage form. As a result of the study with reference oil, the filling volume and the temperature were found to be significant for the rate of leaking capsules. The filling volume was also important for weight variability of the capsules. However, most critical for this variability was the diameter of the filling nozzle. We proposed a power law for the coefficient of weight variability as a function of the nozzle diameter and the obtained exponent agreed with the proposed theory. Subsequently, a comparison of different oils revealed that the relative splashing degree shared a correlation with the coefficient of the capsule weight variability (Pearson product moment correlation of r=0.990). The novel theoretical concept was therefore found to be predictive for weight variability of the filled capsules. Finally, guidance was provided for the process development of liquid-filled capsules using low-viscosity oils. © 2011 American Association of Pharmaceutical Scientists

  16. Water balance of an earth fill built of organic clay

    Directory of Open Access Journals (Sweden)

    Birle Emanuel

    2016-01-01

    Full Text Available The paper presents investigations on the water balance of an earth fill built of organic clay in humid climate. As the organic soil used for the fill contains geogenetically elevated concentrations of arsenic, particular attention is paid on the seepage flow through the fill. The test fill is 5 m high, 30 m long and 25 m wide. The fill consists of the organic clay compacted at water contents wet and dry of Proctor Optimum covered by a drainage mat and a 60 cm thick top layer. For the determination of the water balance extensive measuring systems were installed. The seepage at the bottom measured so far was less than 2 % of the precipitation. The interflow in the drainage mat above the compacted organic clay was of similar magnitude. The estimated evapotranspiration reached approx. 84 % of the precipitation. According to these measurements the percolation is much lower than the percolation of many landfill covers in humid climates.

  17. Development of gap filling technique in HLW repository

    International Nuclear Information System (INIS)

    Nakashima, Hitoshi; Saito, Akira; Ishii, Takashi; Toguri, Satohito; Okihara, Mitsunobu; Iwasa, Kengo

    2016-01-01

    HLW is supposed to be disposed underground at depths more than 300 m in Japan. Buffer is an artificial barrier that controls radionuclides migrating into the groundwater. The buffer would be made of a natural swelling clay, bentonite. Construction technology for the buffer has been studied for many years, but studies for the gaps surrounding the buffer are little. The proper handling of the gaps is important for guaranteeing the functions of the buffer. In this paper, gap filling techniques using bentonite pellets have been developed in order to the gap having the same performance as the buffer. A new method for manufacturing high-density spherical pellets has been developed to fill the gap higher density ever reported. For the bentonite pellets, the filling performance and how to use were determined. And full-scale filling tests provided availability of the bentonite pellets and filling techniques. (author)

  18. Magnetically Active and Coated Gadolinium-Filled Carbon Nanotubes

    KAUST Repository

    Fidiani, Elok; Da Costa, Pedro M. F. J.; Wolter, Anja U. B.; Maier, Diana; Buechner, Bernd; Hampel, Silke

    2013-01-01

    Gd-filled carbon nanotubes (which include the so-called gadonanotubes(1)) have been attracting much interest due to their potential use in medical diagnostic applications. In the present work, a vacuum filling method was performed to confine gadolinium(III) iodide in carbon nanotubes (CNTs). Filling yields in excess of 50% were obtained. Cleaning and dosing of the external walls was undertaken, as well as the study of the filled CNT magnetic properties. Overall, we found that the encapsulating procedure can lead to reduction of the lanthanide metal and induce disorder in the initial GdI3-type structure. Notwithstanding, the magnetic response of the material is not compromised, retaining a strong paramagnetic response and an effective magnetic moment of similar to 6 mu B. Our results may entice further investigation into whether an analogous Gd3+ to Gd2+ reduction takes place in other Gd-filled CNT systems.

  19. Magnetically Active and Coated Gadolinium-Filled Carbon Nanotubes

    KAUST Repository

    Fidiani, Elok

    2013-08-15

    Gd-filled carbon nanotubes (which include the so-called gadonanotubes(1)) have been attracting much interest due to their potential use in medical diagnostic applications. In the present work, a vacuum filling method was performed to confine gadolinium(III) iodide in carbon nanotubes (CNTs). Filling yields in excess of 50% were obtained. Cleaning and dosing of the external walls was undertaken, as well as the study of the filled CNT magnetic properties. Overall, we found that the encapsulating procedure can lead to reduction of the lanthanide metal and induce disorder in the initial GdI3-type structure. Notwithstanding, the magnetic response of the material is not compromised, retaining a strong paramagnetic response and an effective magnetic moment of similar to 6 mu B. Our results may entice further investigation into whether an analogous Gd3+ to Gd2+ reduction takes place in other Gd-filled CNT systems.

  20. ADVANTAGES AND DISADVANTAGES OF THE SONICFILL™ METHOD FOR LATERAL FILLINGS

    Directory of Open Access Journals (Sweden)

    Nicolae BARANOV

    2017-06-01

    Full Text Available The aim of the study was to evaluate the advantages and disadvantages of bulk-fill type fillings realized with SONICFill™ over an 18 month interval, on a batch of patients with different ages and occupations. Materials and methods: the study was performed on a batch of 73 patients who addressed the Clinical of OdontologyEndodontics within the Platform of Practical Training (PIP of the Faculty of Dental Medicine of the ”Apollonia” University of Iaşi, between Octomber 1, 2014 - May 1, 2016, subjected to 91 bulk-fill fillings with SonicFill™ on the posterior teeth. Results and discussion: out of the total number of 73 patients, 56 came from the urban environment, and 17 - from the rural medium, the highest ratio being represented by the 21-30 year age group (45%, closely followed by the 31-40 year one (40%. As for gender distribution within the batch, nearly two-thirds are women, the rest being men. The education level influenced patients’ decision – that of accepting a new method of filling application. As to the types of teeth to which restorations were applied, the highest ratio is represented by lower molars (41%, followed by upper molars (23% and mandibular premolars (20%, the lowest number of restorations being applied to maxillary premolars. Out of the total number of 91 bulk-fill restorations, 28 were applied over a base filling while, in 63 restorations, the basic filling was absent. Conclusions: The SonicFill ™ system for bulk-fill posterior restorations has a number of advantages, such as: high photopolymerization depth, significant reduction of setting contraction, better composite adaptation to the cavity walls, long-term predictable clinical results.

  1. Quality of root fillings performed with two root filling techniques. An in vitro study using micro-CT

    DEFF Research Database (Denmark)

    Møller, L; Wenzel, A; Wegge-Larsen, AM

    2013-01-01

    -section images from Micro-computed Tomography scans. Results. All root canal fillings had voids. Permutation test showed no statistically significant difference between the two root filling techniques in relation to presence of voids (p = 0.092). A statistically significant difference in obturation time between...

  2. The water-filled versus air-filled status of vessels cut open in air: the 'Scholander assumption' revisited

    Science.gov (United States)

    M.T. Tyree; H. Cochard; P. Cruziat

    2003-01-01

    When petioles of transpiring leaves are cut in the air, according to the 'Scholander assumption', the vessels cut open should fill with air as the water is drained away by continued transpiration, The distribution of air-filled vessels versus distance from the cut surface should match the distribution of lengths of 'open vessels', i.e. vessels cut...

  3. Characterization of vegetative and grain filling periods of winter wheat by stepwise regression procedure. II. Grain filling period

    Directory of Open Access Journals (Sweden)

    Pržulj Novo

    2011-01-01

    Full Text Available In wheat, rate and duration of dry matter accumulation and remobilization depend on genotype and growing conditions. The objective of this study was to determine the most appropriate polynomial regression of stepwise regression procedure for describing grain filling period in three winter wheat cultivars. The stepwise regression procedure showed that grain filling is a complex biological process and that it is difficult to offer a simple and appropriate polynomial equation that fits the pattern of changes in dry matter accumulation during the grain filling period, i.e., from anthesis to maximum grain weight, in winter wheat. If grain filling is to be represented with a high power polynomial, quartic and quintic equations showed to be most appropriate. In spite of certain disadvantages, a cubic equation of stepwise regression could be used for describing the pattern of winter wheat grain filling.

  4. Silver nanoparticles deposited on amine-functionalized silica spheres and their amalgamation-based spectral and colorimetric detection of Hg(II) ions

    Energy Technology Data Exchange (ETDEWEB)

    Rameshkumar, Perumal; Manivannan, Shanmugam; Ramaraj, Ramasamy, E-mail: ramarajr@yahoo.com [Madurai Kamaraj University, Centre for Photoelectrochemistry, School of Chemistry (India)

    2013-05-15

    A facile synthetic method to decorate amine-functionalized silica spheres (SiO{sub 2}) by silver nanoparticles (Ag NPs) is reported. The transmission electron microscopic (TEM) images showed that spherical Ag NPs with an average particle size of 14 nm were deposited on 250 nm-sized SiO{sub 2} spheres (SiO{sub 2}/Ag NPs). The spectral and colorimetric detection of Hg(II) ions were carried out using the synthesized SiO{sub 2}/Ag NPs with an experimental detection limit of 5 {mu}M. It was found that the addition of Hg(II) ions (150 {mu}M) into the solution of SiO{sub 2}/Ag NPs completely quenched the SPR band of the Ag NPs due to the formation of anisotropic Ag amalgam crystals (AgHg). The selective detection of Hg(II) ions by SiO{sub 2}/Ag NPs in the presence of other environmentally relevant metal ions was also demonstrated using spectral and colorimetric methods.Graphical abstractAmine-functionalized silica spheres are decorated by in situ formation of silver nanoparticles and their spectral and colorimetric detection of Hg(II) ions is reported.

  5. Effect of Cooling Rate on the Longitudinal Modulus of Cu3Sn Phase of Ag-Sn-Cu Amalgam Alloy (Part II

    Directory of Open Access Journals (Sweden)

    R. H. Rusli

    2015-10-01

    Full Text Available Effects of cooling rate (at the time of solidification on the elastic constants of Cu3Sn phase of Ag-Sn-Cu dental amalgam alloy were studied. In this study, three types of alloys were made, with the composition Cu-38-37 wt% Sn by means of casting, where each alloy was subjected to different cooling rate, such as cooling on the air (AC, air blown (AB, and quenched in the water (WQ. X-ray diffraction, metallography, and Scanning Electron Microscopy with Energy Dispersive Spectroscopy studies of three alloys indicated the existence of Cu3Sn phase. Determination of the modulus of elasticity of Cu3Sn (ε phase was carried out by the measurement of longitudinal and transversal waves velocity using ultrasonic technique. The result shows that Cu3Sn (ε phase on AC gives higher modulus of elasticity values than those of Cu3Sn (ε on AB and WQ. The high modulus of elasticity value will produce a strong Ag-Sn-Cu dental amalagam alloy.

  6. Perawatan Saluran Akar Ulang Pasca Pengisian Saluran Akar dengan Amalgam dan Perforasi Lateral Disertai Restorasi Mahkota Penuh Porselin Fusi Metal dengan Inti Pasak Fiber (pada Insisivus Sentralis Kanan dan Kiri Maksila

    Directory of Open Access Journals (Sweden)

    Setiawan Wibiksono

    2011-06-01

    Full Text Available Kegagalan perawatan saluran akar dapat mengakibatkan beberapa masalah baru yang mengganggu fungsi dari gigi yang telah dirawat. Perawatan saluran akar ulang bertujuan menghilangkan bahan dari saluran akar serta memperbaiki kerusakan yang iatrogenik maupun patologik oleh karena kegagalan perawatan sebelumnya. Tujuan. Penulisan laporan untuk mengevaluasi hasil perawatan saluran akar ulang pada gigi insisivus sentralis kanan dan kiri maksila non vital pasea pengisian saluran akar dengan amalgam disertai restorasi mahkota penuh porselin fusi metal dengan inti pasak fiber. Kasus. Pasien laki-Iaki berusia 23 tahun datang ke Klinik Konservasi Gigi FKG UGM ingin memperbaiki gigi depan atas yang berubah warna. Gigi tersebut 5 tahun yang lalu pernah dirawat karena mengalami trauma akibat jatuh. Pada pemeriksaan objektif, tampak gigi 11 dan 21 fraktur 1/3 mahkota, tampak berubah warna, dan tampak bahan amalgam pada dasar kavitas. Pada pemeriksaan radiografis gigi 11 dan 21, .terlihat gambaran radiopak (amalgam memanjang pada saluran akar, tidak terlihat pengisan saluran akar, dan tampak perforasi lateral pada gigi 11. Diagnosis gigi 11 dan 21 adalah fraktur Ellis kelas III non vital. Penanganan: Prosedur perawatan yang dilakukan adalah penutupan perforasi lateral gigi 11 menggunakan MTA; perawatan saluran akar satu kunjungan; restorasi akhir mahkota penuh porselin fusi metal dengan inti pasak fiber. Evaluasi setelah satu bulan menunjukkan tidak ada keluhan, perkusi dan palpasi negatif, oklusi normal, gigi 11 dan 21 kembali berfungsi normal, terutama fungsi estetis. Kesimpulan: Perawatan saluran akar ulang dan restorasi pada kasus ini dapat mengembalikan fungsi mastikasi, fonetik, estetik, maupun perlindungan terhadap jaringan pendukung pada gigi tersebut.

  7. Geomechanical investigations for the designing of cemented filling

    Energy Technology Data Exchange (ETDEWEB)

    Berry, P.

    1980-05-15

    Laboratory and in situ investigations have led to the identification of the main geomechanical parameters that condition the stability of the cemented fill in the Gavorrano pyrite mine (Tuscany, Italy); such parameters were used for working out a satisfactory mining method. The pyrite is mined with the descending horizontal slice method with integral cemented filling which is obtained by throwing a mixture of limestone aggregates and cement into the mined voids. The laboratory geomechanical investigations carried out on fill samples have pointed out that the physical and mechanical characteristics are highly variable and this is essentially due to the fact that the fill is cast into place by compressed air. In particular, it was pointed out that the strength depends upon the cement content and upon the porosity according to a power law. The in situ measurements of the convergence between the roof and the floor, and the load measurements pointed out the considerable importance of the horizontal and vertical joints that cross the fill mass and that are inevitably brought about by a discontinuity of the fill. The results of the study made it possible to adopt an acceptable geomechanical behaviour model of the fill. On the basis of this model the mining pattern was deeply modified, the width and the height of the slices were considerably enlarged and thus the output was improved.

  8. Modeling and Fault Simulation of Propellant Filling System

    International Nuclear Information System (INIS)

    Jiang Yunchun; Liu Weidong; Hou Xiaobo

    2012-01-01

    Propellant filling system is one of the key ground plants in launching site of rocket that use liquid propellant. There is an urgent demand for ensuring and improving its reliability and safety, and there is no doubt that Failure Mode Effect Analysis (FMEA) is a good approach to meet it. Driven by the request to get more fault information for FMEA, and because of the high expense of propellant filling, in this paper, the working process of the propellant filling system in fault condition was studied by simulating based on AMESim. Firstly, based on analyzing its structure and function, the filling system was modular decomposed, and the mathematic models of every module were given, based on which the whole filling system was modeled in AMESim. Secondly, a general method of fault injecting into dynamic system was proposed, and as an example, two typical faults - leakage and blockage - were injected into the model of filling system, based on which one can get two fault models in AMESim. After that, fault simulation was processed and the dynamic characteristics of several key parameters were analyzed under fault conditions. The results show that the model can simulate effectively the two faults, and can be used to provide guidance for the filling system maintain and amelioration.

  9. Radio resource management using geometric water-filling

    CERN Document Server

    He, Peter; Zhou, Sheng; Niu, Zhisheng

    2014-01-01

    This brief introduces the fundamental theory and development of managing radio resources using a water-filling algorithm that can optimize system performance in wireless communication. Geometric Water-Filling (GWF) is a crucial underlying tool in emerging communication systems such as multiple input multiple output systems, cognitive radio systems, and green communication systems. Early chapters introduce emerging wireless technologies and provide a detailed analysis of water-filling. The brief investigates single user and multi-user issues of radio resource management, allocation of resources

  10. Measuring Item Fill-Rate Performance in a Finite Horizon

    OpenAIRE

    Douglas J. Thomas

    2005-01-01

    The standard treatment of fill rate relies on stationary and serially independent demand over an infinite horizon. Even if demand is stationary, managers are held accountable for performance over a finite horizon. In a finite horizon, the fill rate is a random variable. Studying the distribution is relevant because a vendor may be subject to financial penalty if she fails to achieve her target fill rate over a specified finite period. It is known that for a zero lead time, base-stock model, t...

  11. Fill Rates of Single-Stage and Multistage Supply Systems

    OpenAIRE

    Matthew J. Sobel

    2004-01-01

    A supply system's fill rate is the fraction of demand that is met from on-hand inventory. This paper presents formulas for the fill rate of periodic review supply systems that use base-stock-level policies. The first part of the paper contains fill-rate formulas for a single-stage system and general distributions of demand. When demand is normally distributed, an exact expression uses only the standard normal distribution and density functions, and a good approximation uses only the standard ...

  12. Biocompatibility of root-end filling materials: recent update

    Directory of Open Access Journals (Sweden)

    Payal Saxena

    2013-08-01

    Full Text Available The purpose of a root-end filling is to establish a seal between the root canal space and the periradicular tissues. As root-end filling materials come into contact with periradicular tissues, knowledge of the tissue response is crucial. Almost every available dental restorative material has been suggested as the root-end material of choice at a certain point in the past. This literature review on root-end filling materials will evaluate and comparatively analyse the biocompatibility and tissue response to these products, with primary focus on newly introduced materials.

  13. Production of staphylococcal enterotoxin A in cream-filled cake.

    Science.gov (United States)

    Anunciaçao, L L; Linardi, W R; do Carmo, L S; Bergdoll, M S

    1995-07-01

    Cakes were baked with normal ingredients and filled with cream, inoculated with different size enterotoxigenic-staphylococcal inocula. Samples of the cakes were incubated at room temperature and put in the refrigerator. Samples of cake and filling were taken at different times and analyzed for staphylococcal count and presence of enterotoxin. The smaller the inoculum, the longer the time required for sufficient growth (10(6)) to occur for production of detectable enterotoxin. Enterotoxin added to the cake dough before baking (210 degrees C, 45 min) did not survive the baking. The presence of enterotoxin in the contaminated cream filling indicated this as the cause of staphylococcal food poisoning from cream-filled cakes. Refrigeration of the cakes prevented the growth of the staphylococci.

  14. Beeswax as dental filling on a neolithic human tooth.

    Science.gov (United States)

    Bernardini, Federico; Tuniz, Claudio; Coppa, Alfredo; Mancini, Lucia; Dreossi, Diego; Eichert, Diane; Turco, Gianluca; Biasotto, Matteo; Terrasi, Filippo; De Cesare, Nicola; Hua, Quan; Levchenko, Vladimir

    2012-01-01

    Evidence of prehistoric dentistry has been limited to a few cases, the most ancient dating back to the Neolithic. Here we report a 6500-year-old human mandible from Slovenia whose left canine crown bears the traces of a filling with beeswax. The use of different analytical techniques, including synchrotron radiation computed micro-tomography (micro-CT), Accelerator Mass Spectrometry (AMS) radiocarbon dating, Infrared (IR) Spectroscopy and Scanning Electron Microscopy (SEM), has shown that the exposed area of dentine resulting from occlusal wear and the upper part of a vertical crack affecting enamel and dentin tissues were filled with beeswax shortly before or after the individual's death. If the filling was done when the person was still alive, the intervention was likely aimed to relieve tooth sensitivity derived from either exposed dentine and/or the pain resulting from chewing on a cracked tooth: this would provide the earliest known direct evidence of therapeutic-palliative dental filling.

  15. Beeswax as dental filling on a neolithic human tooth.

    Directory of Open Access Journals (Sweden)

    Federico Bernardini

    Full Text Available Evidence of prehistoric dentistry has been limited to a few cases, the most ancient dating back to the Neolithic. Here we report a 6500-year-old human mandible from Slovenia whose left canine crown bears the traces of a filling with beeswax. The use of different analytical techniques, including synchrotron radiation computed micro-tomography (micro-CT, Accelerator Mass Spectrometry (AMS radiocarbon dating, Infrared (IR Spectroscopy and Scanning Electron Microscopy (SEM, has shown that the exposed area of dentine resulting from occlusal wear and the upper part of a vertical crack affecting enamel and dentin tissues were filled with beeswax shortly before or after the individual's death. If the filling was done when the person was still alive, the intervention was likely aimed to relieve tooth sensitivity derived from either exposed dentine and/or the pain resulting from chewing on a cracked tooth: this would provide the earliest known direct evidence of therapeutic-palliative dental filling.

  16. Simulation of mould filling process for composite skeleton castings

    OpenAIRE

    M. Dziuba; M. Cholewa

    2008-01-01

    In this work authors showed selected results of simulation and experimental studies on temperature distribution during solidification of skeleton casting and mould filling process. The aim of conducted simulations was the choice of thermal and geometrical parameters for the needs of designed calculations of the skeleton castings and the estimation of the guidelines for the technology of manufacturing. The subject of numerical simulation was the analysis of ability of filling the channels of c...

  17. Time effects of water drainage from deposited back-fill

    International Nuclear Information System (INIS)

    Baranski, L.A.

    1976-01-01

    Time effects of water drainage from deposited back-fill in mine excavations are considered. The time dependence of drainage from the deposited material was determined from ''in situ'' measurements with the aid of radioisotope gauges. The measurements were performed for given drainage conditions and practically constant grain size composition. It was found that in a few hours after the end of the back-filling operation the mechanical properties of the deposited material are practically constant. (author)

  18. Method for filling a reactor with a catalyst

    DEFF Research Database (Denmark)

    2013-01-01

    The invention relates to a method for filling a reactor with a catalyst for the carbonylation of carbonylated compounds in the gas phase. According to said method, a SILP catalyst is covered with a filling agent which is liquid under normal conditions and is volatile under carbonylation reaction...... conditions, and a thus-treated catalyst is introduced into the reactor and the reactor is sealed....

  19. Countering Stryker’s Punch: Algorithmically Filling the Black Hole

    OpenAIRE

    Michael J. Bennett

    2017-01-01

    Two current digital image editing programs are examined in the context of filling in missing visual image data from hole-punched United States Farm Security Administration (FSA) negatives. Specifically, Photoshop's Content-Aware Fill feature and GIMP's Resynthesizer plugin are evaluated and contrasted against comparable images. A possible automated workflow geared towards large scale editing of similarly hole-punched negatives is also explored. Finally, potential future research based upon th...

  20. Grain filling parameters and yield components in wheat

    OpenAIRE

    Brdar Milka; Kobiljski Borislav; Balalić-Kraljević Marija

    2006-01-01

    Grain yield of wheat (Triticum aestivum L.) is influenced by number of grains per unit area and grain weight, which is result of grain filling duration and rate. The aim of the study was to investigate the relationships between grain filling parameters in 4 wheat genotypes of different earliness and yield components. Nonlinear regression estimated and observed parameters were analyzed. Rang of estimated parameters corresponds to rang of observed parameters. Stepwise MANOVA indicated that the ...

  1. Vibration characteristics of teak wood filled steel tubes

    Science.gov (United States)

    Danawade, Bharatesh Adappa; Malagi, Ravindra Rachappa

    2018-05-01

    The objective of this paper is to determine fundamental frequency and damping ratio of teak wood filled steel tubes. Mechanically bonded teak wood filled steel tubes have been evaluated by experimental impact hammer test using modal analysis. The results of impact hammer test were verified and validated by finite element tool ANSYS using harmonic analysis. The error between the two methods was observed to be within acceptable limit.

  2. Is a three-dimensional-printed tooth filling possible?

    OpenAIRE

    Muhammet Kerim Ayar

    2016-01-01

    Introduction: Three-dimensional (3-D) printing is seen as an innovative production process in many fields of dentistry and medicine. But implantation of this novel production process into the treatment of decayed teeth in dentistry remains lacking. Destruction of dental tissues as a result of dental caries is generally treated with dental resin composite fillings. However, a 3-D-printed tooth filling approach, which could be an alternative to traditional approaches, has a potential to reduce ...

  3. Fluid dynamics following flow shut-off in bottle filling

    Science.gov (United States)

    Thete, Sumeet; Appathurai, Santosh; Gao, Haijing; Basaran, Osman

    2012-11-01

    Bottle filling is ubiquitous in industry. Examples include filling of bottles with shampoos and cleaners, engine oil and pharmaceuticals. In these examples, fluid flows out of a nozzle to fill bottles in an assembly line. Once the required volume of fluid has flowed out of the nozzle, the flow is shut off. However, an evolving fluid thread or string may remain suspended from the nozzle following flow shut-off and persist. This stringing phenomenon can be detrimental to a bottle filling operation because it can adversely affect line speed and filling accuracy by causing uncertainty in fill volume, product loss and undesirable marring of the bottles' exterior surfaces. The dynamics of stringing are studied numerically primarily by using the 1D, slender-jet approximation of the flow equations. A novel feature entails development and use of a new boundary condition downstream of the nozzle exit to expedite the computations. While the emphasis is on stringing of Newtonian fluids and use of 1D approximations, results will also be presented for situations where (a) the fluids are non-Newtonian and (b) the full set of equations are solved without invoking the 1D approximation. Phase diagrams will be presented that identify conditions for which stringing can be problematic.

  4. Field configurations for small deviations of the integral filling factors in IQHE

    International Nuclear Information System (INIS)

    Cabo, A.; Castineiras, J.; Gonzalez, R.; Penaranda, S.

    1990-07-01

    A numerical solution of the effective Maxwell equations of the IQHE is presented. It corresponds to inhomogeneous electromagnetic field distributions appearing after a small constant magnetic field is added to a 2D-electron gas sheet when the density exactly fills an integral number of Landau levels. It follows that the Chern-Simons terms of the Maxwell equation transform the applied magnetic field into an equivalent homogeneous charge density. The numerical value of this density is exactly the one which is needed to furnish complete filling at the new value of the total magnetic field. The system then reacts tending to screen the effective charge density by removing charge from the sample edges. It is interesting that for the selected parameter values here, reflecting the current experimental situations, the system response is able to approximately establish an integral filling factor in the central portion of the sheet. Then, at least a small plateau is predicted to occur in pure samples at zero temperature. It also follows that the current distribution is unsymmetric under the inversion, as opposed to the configuration associated to a flow of a net Hall current at integral filling factors. (author). 8 refs, 4 figs

  5. Demonstrated high performance of gas-filled rugby-shaped hohlraums on Omega

    Energy Technology Data Exchange (ETDEWEB)

    Philippe, F.; Villette, B. [CEA, DAM, DIF, F-91297 Arpajon (France); Michel, P. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Petrasso, R. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Stoeckl, C. [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623 (United States); Giraldez, E. [General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States); Tassin, V.; Depierreux, S.; Gauthier, P.; Masson-Laborde, P. E.; Monteil, M. C.; Seytor, P.; Lasinski, B.; Park, H. S.; Ross, J. S.; Amendt, P.; Döppner, T.; Hinkel, D. E.; Wallace, R.; Williams, E.; and others

    2014-07-15

    A direct experimental comparison of rugby-shaped and cylindrical shaped gas-filled hohlraums on the Omega laser facility demonstrates that higher coupling and minimal backscatter can be achieved in the rugby geometry, leading to significantly enhanced implosion performance. A nearly 50% increase of x-ray drive is associated with earlier bangtime and increase of neutron production. The observed drive enhancement from rugby geometry in this study is almost twice stronger than in previously published results.

  6. Demonstrated high performance of gas-filled rugby-shaped hohlraums on Omega

    Science.gov (United States)

    Philippe, F.; Tassin, V.; Depierreux, S.; Gauthier, P.; Masson-Laborde, P. E.; Monteil, M. C.; Seytor, P.; Villette, B.; Lasinski, B.; Park, H. S.; Ross, J. S.; Amendt, P.; Döppner, T.; Hinkel, D. E.; Wallace, R.; Williams, E.; Michel, P.; Frenje, J.; Gatu-Johnson, M.; Li, C. K.; Petrasso, R.; Glebov, V.; Sorce, C.; Stoeckl, C.; Nikroo, A.; Giraldez, E.

    2014-07-01

    A direct experimental comparison of rugby-shaped and cylindrical shaped gas-filled hohlraums on the Omega laser facility demonstrates that higher coupling and minimal backscatter can be achieved in the rugby geometry, leading to significantly enhanced implosion performance. A nearly 50% increase of x-ray drive is associated with earlier bangtime and increase of neutron production. The observed drive enhancement from rugby geometry in this study is almost twice stronger than in previously published results.

  7. Demonstrated high performance of gas-filled rugby-shaped hohlraums on Omega

    International Nuclear Information System (INIS)

    Philippe, F.; Villette, B.; Michel, P.; Petrasso, R.; Stoeckl, C.; Giraldez, E.; Tassin, V.; Depierreux, S.; Gauthier, P.; Masson-Laborde, P. E.; Monteil, M. C.; Seytor, P.; Lasinski, B.; Park, H. S.; Ross, J. S.; Amendt, P.; Döppner, T.; Hinkel, D. E.; Wallace, R.; Williams, E.

    2014-01-01

    A direct experimental comparison of rugby-shaped and cylindrical shaped gas-filled hohlraums on the Omega laser facility demonstrates that higher coupling and minimal backscatter can be achieved in the rugby geometry, leading to significantly enhanced implosion performance. A nearly 50% increase of x-ray drive is associated with earlier bangtime and increase of neutron production. The observed drive enhancement from rugby geometry in this study is almost twice stronger than in previously published results

  8. Particle creation in a universe filled with radiation and dust-like matter

    International Nuclear Information System (INIS)

    Villalba, V.M.

    1993-01-01

    In this article the particle creation process of scalar and spin 1/2 particles in a spatially open cosmological model associated with a universe filled with radiation and dustlike matter is analyzed. The Klein-Gordon and the Dirac equations are solved via separation of variables. After comparing the in and out vacua, we obtain that the number of created particles corresponds to Planckian and Fermi-Dirac distributions for the scalar and Dirac cases respectively. (author)

  9. Demonstrated high performance of gas-filled rugby-shaped hohlraums on Omega

    Energy Technology Data Exchange (ETDEWEB)

    Philippe, F. [Commissariat a l' Energie Atomique et aux Energies Alternatives (CEA), Arpajon (France); Tassin, V. [Commissariat a l' Energie Atomique et aux Energies Alternatives (CEA), Arpajon (France); Depierreux, S. [Commissariat a l' Energie Atomique et aux Energies Alternatives (CEA), Arpajon (France); Gauthier, P. [Commissariat a l' Energie Atomique et aux Energies Alternatives (CEA), Arpajon (France); Masson-Laborde, P. E. [Commissariat a l' Energie Atomique et aux Energies Alternatives (CEA), Arpajon (France); Monteil, M. C. [Commissariat a l' Energie Atomique et aux Energies Alternatives (CEA), Arpajon (France); Seytor, P. [Commissariat a l' Energie Atomique et aux Energies Alternatives (CEA), Arpajon (France); Villette, B. [Commissariat a l' Energie Atomique et aux Energies Alternatives (CEA), Arpajon (France); Lasinski, B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Park, H. S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Ross, J. S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Amendt, P. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Doeppner, T. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Hinkel, D. E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Wallace, R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Williams, E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Michel, P. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Frenje, J. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Plasma Science and Fusion Center; Gatu-Johnson, M. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Plasma Science and Fusion Center; Li, C. K. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Plasma Science and Fusion Center; Petrasso, R. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Plasma Science and Fusion Center; Glebov, V. [Univ. of Rochester, NY (United States). Lab. for Laser Energetics; Sorce, C. [Univ. of Rochester, NY (United States). Lab. for Laser Energetics; Stoeckl, C. [Univ. of Rochester, NY (United States). Lab. for Laser Energetics; Nikroo, A. [General Atomics, San Diego, CA (United States); Giraldez, E. [General Atomics, San Diego, CA (United States)

    2014-07-25

    A direct experimental comparison of rugby-shaped and cylindrical shaped gas-filled hohlraums on the Omega laser facility demonstrates that higher coupling and minimal backscatter can be achieved in the rugby geometry, leading to significantly enhanced implosion performance. A nearly 50% increase of x-ray drive is associated with earlier bangtime and increase of neutron production. The observed drive enhancement from rugby geometry in this study is almost twice stronger than in previously published results.

  10. To Fill or Not to Fill: Sensitivity Analysis of the Influence of Resolution and Hole Filling on Point Cloud Surface Modeling and Individual Rockfall Event Detection

    Directory of Open Access Journals (Sweden)

    Michael J. Olsen

    2015-09-01

    Full Text Available Monitoring unstable slopes with terrestrial laser scanning (TLS has been proven effective. However, end users still struggle immensely with the efficient processing, analysis, and interpretation of the massive and complex TLS datasets. Two recent advances described in this paper now improve the ability to work with TLS data acquired on steep slopes. The first is the improved processing of TLS data to model complex topography and fill holes. This processing step results in a continuous topographic surface model that seamlessly characterizes the rock and soil surface. The second is an advance in the automated interpretation of the surface model in such a way that a magnitude and frequency relationship of rockfall events can be quantified, which can be used to assess maintenance strategies and forecast costs. The approach is applied to unstable highway slopes in the state of Alaska, U.S.A. to evaluate its effectiveness. Further, the influence of the selected model resolution and degree of hole filling on the derived slope metrics were analyzed. In general, model resolution plays a pivotal role in the ability to detect smaller rockfall events when developing magnitude-frequency relationships. The total volume estimates are also influenced by model resolution, but were comparatively less sensitive. In contrast, hole filling had a noticeable effect on magnitude-frequency relationships but to a lesser extent than modeling resolution. However, hole filling yielded a modest increase in overall volumetric quantity estimates. Optimal analysis results occur when appropriately balancing high modeling resolution with an appropriate level of hole filling.

  11. Amalgam Electrode-Based Electrochemical Detector for On-Site Direct Determination of Cadmium(II and Lead(II from Soils

    Directory of Open Access Journals (Sweden)

    Lukas Nejdl

    2017-08-01

    Full Text Available Toxic metal contamination of the environment is a global issue. In this paper, we present a low-cost and rapid production of amalgam electrodes used for determination of Cd(II and Pb(II in environmental samples (soils and wastewaters by on-site analysis using difference pulse voltammetry. Changes in the electrochemical signals were recorded with a miniaturized potentiostat (width: 80 mm, depth: 54 mm, height: 23 mm and a portable computer. The limit of detection (LOD was calculated for the geometric surface of the working electrode 15 mm2 that can be varied as required for analysis. The LODs were 80 ng·mL−1 for Cd(II and 50 ng·mL−1 for Pb(II, relative standard deviation, RSD ≤ 8% (n = 3. The area of interest (Dolni Rozinka, Czech Republic was selected because there is a deposit of uranium ore and extreme anthropogenic activity. Environmental samples were taken directly on-site and immediately analysed. Duration of a single analysis was approximately two minutes. The average concentrations of Cd(II and Pb(II in this area were below the global average. The obtained values were verified (correlated by standard electrochemical methods based on hanging drop electrodes and were in good agreement. The advantages of this method are its cost and time effectivity (approximately two minutes per one sample with direct analysis of turbid samples (soil leach in a 2 M HNO3 environment. This type of sample cannot be analyzed using the classical analytical methods without pretreatment.

  12. Conditioning of renewable silver amalgam film electrode for the characterization of clothianidin and its determination in selected samples by adsorptive square-wave voltammetry.

    Science.gov (United States)

    Brycht, Mariola; Skrzypek, Sławomira; Guzsvány, Valéria; Berenji, Janoš

    2013-12-15

    A new square-wave adsorptive stripping voltammetric (SWAdSV) method was developed for the determination of the neonicotinoid insecticide clothianidin (Clo), based on its reduction at a renewable silver amalgam film electrode (Hg(Ag)FE). The key point of the procedure is the pretreatment of the Hg(Ag)FE by applying the appropriate conditioning potential (-1.70 V vs. Ag/AgCl reference electrode). Under the optimized voltammetric conditions, such pretreatment resulted in the peak for the Clo reduction in Britton-Robinson buffer pH 9.0 at about -0.60 V, which was used for the analytical purpose. The developed SWAdSV procedure made it possible to determine Clo in the concentration range of 6.0×10(-7)-7.0×10(-6) mol L(-1) (LOD=1.8×10(-7) mol L(-1), LOQ=6.0×10(-7) mol L(-1)) and 7.0×10(-6)-4.0×10(-5) mol L(-1) (LOD=1.3×10(-6) mol L(-1), LOQ=4.2×10(-6) mol L(-1)). The repeatability, precision, and the recovery of the method were determined. The effect of common interfering pesticides was also investigated. Standard addition method was successfully applied and validated for the determination of Clo in spiked Warta River water, corn seeds samples, and in corn seeds samples treated with the commercial formulation PONCHO 600 FS. © 2013 Elsevier B.V. All rights reserved.

  13. The Use of Silver Solid Amalgam Electrodes for Voltammetric and Amperometric Determination of Nitrated Polyaromatic Compounds Used as Markers of Incomplete Combustion

    Directory of Open Access Journals (Sweden)

    Oksana Yosypchuk

    2012-01-01

    Full Text Available Genotoxic nitrated polycyclic aromatic hydrocarbons (NPAHs are formed during incomplete combustion processes by reaction of polycyclic aromatic hydrocarbons (PAHs with atmospheric nitrogen oxides. 1-Nitropyrene, 2-nitrofluorene, and 3-nitrofluoranthene as the dominating substances are used as markers of NPAHs formation by these processes. In the presented study, voltammetric properties and quantification of these compounds and of 5-nitroquinoline (as a representative of environmentally important genotoxic heterocyclic compounds have been investigated using a mercury meniscus modified silver solid amalgam electrode (m-AgSAE, which represent a nontoxic alternative to traditional mercury electrodes. Linear calibration curves over three orders of magnitude and limits of determination mostly in the 10−7 mol L−1 concentration range were obtained using direct current and differential pulse voltammetry. Further, satisfactory HPLC separation of studied analytes in fifteen minutes was achieved using 0.01 mol L−1 phosphate buffer, pH 7.0 : methanol (15 : 85, v/v mobile phase, and C18 reversed stationary phase. Limits of detection of around 1 · 10−5 mol L−1 were achieved using amperometric detection at m-AgSAE in wall-jet arrangement for all studied analytes. Practical applicability of this technique was demonstrated on the determination of 1-nitropyrene, 2-nitrofluorene, 3-nitrofluoranthene, and 5-nitroquinoline in drinking water after their preliminary separation and preconcentration using solid phase extraction with the limits of detection around 1 · 10−6 mol L−1.

  14. Determination of mercury and its fractionation products in samples from legacy use of mercury amalgam in gold processing in Randfontein, South Africa

    Directory of Open Access Journals (Sweden)

    Tshia Malehase

    2016-09-01

    Full Text Available This study aimed at determining the levels of total mercury (THg in tailings dams, soil, sediments and water samples collected in the vicinity of legacy mercury amalgam gold mines. Acid digestion was employed in sample digestion followed by analysis using CVAAS. Tailings dams, community and garden soil, and stream sediments were further investigated for mercury fractions using a five step sequential extraction procedure. The concentrations of THg in tailings dams, community and gardens soil were 0.890–6.755 μg/g, 0.431–0.968 μg/g and 0.471–1.019 μg/g, respectively and the concentrations of THg in the sediments obtained from tailings dams, streams and wetlands were 0.649–1.998 μg/g, 0.604–1.356 μg/g and 0.681–1.356 μg/g, respectively. The concentrations of THg, in aqueous samples obtained from tailings, streams and wetlands were 0.032–0.070 μg/l, 0.004–0.068 μg/l and 0.007–0.012 μg/l, respectively. The sequential extraction procedure showed that most Hg in the tailings dams was largely elemental Hg and Hg bound to sulphur. Soil and sediments were largely dominated by organic bound Hg. Moderate seasonal correlation was observed in tailings dams soil, but weak seasonal correlation in soils collected in the vicinity of tailings. However, a strong seasonal correlation was observed in sediments and water samples. The concentrations of Hg obtained largely existed in organic and sulphate bound Hg and there is elevated potential to methylate Hg.

  15. Method validation for control determination of mercury in fresh fish and shrimp samples by solid sampling thermal decomposition/amalgamation atomic absorption spectrometry.

    Science.gov (United States)

    Torres, Daiane Placido; Martins-Teixeira, Maristela Braga; Cadore, Solange; Queiroz, Helena Müller

    2015-01-01

    A method for the determination of total mercury in fresh fish and shrimp samples by solid sampling thermal decomposition/amalgamation atomic absorption spectrometry (TDA AAS) has been validated following international foodstuff protocols in order to fulfill the Brazilian National Residue Control Plan. The experimental parameters have been previously studied and optimized according to specific legislation on validation and inorganic contaminants in foodstuff. Linearity, sensitivity, specificity, detection and quantification limits, precision (repeatability and within-laboratory reproducibility), robustness as well as accuracy of the method have been evaluated. Linearity of response was satisfactory for the two range concentrations available on the TDA AAS equipment, between approximately 25.0 and 200.0 μg kg(-1) (square regression) and 250.0 and 2000.0 μg kg(-1) (linear regression) of mercury. The residues for both ranges were homoscedastic and independent, with normal distribution. Correlation coefficients obtained for these ranges were higher than 0.995. Limits of quantification (LOQ) and of detection of the method (LDM), based on signal standard deviation (SD) for a low-in-mercury sample, were 3.0 and 1.0 μg kg(-1), respectively. Repeatability of the method was better than 4%. Within-laboratory reproducibility achieved a relative SD better than 6%. Robustness of the current method was evaluated and pointed sample mass as a significant factor. Accuracy (assessed as the analyte recovery) was calculated on basis of the repeatability, and ranged from 89% to 99%. The obtained results showed the suitability of the present method for direct mercury measurement in fresh fish and shrimp samples and the importance of monitoring the analysis conditions for food control purposes. Additionally, the competence of this method was recognized by accreditation under the standard ISO/IEC 17025.

  16. Vincristine sulfate loaded dextran microspheres amalgamated with thermosensitive gel offered sustained release and enhanced cytotoxicity in THP-1, human leukemia cells: In vitro and in vivo study.

    Science.gov (United States)

    Thakur, Vivek; Kush, Preeti; Pandey, Ravi Shankar; Jain, Upendra Kumar; Chandra, Ramesh; Madan, Jitender

    2016-04-01

    Vincristine sulfate (VCS) is a drug of choice for the treatment of childhood and adult acute lymphocytic leukemia, Hodgkin's, non-Hodgkin's lymphoma as well as solid tumors including sarcomas. However, poor biopharmaceutical and pharmacokinetic traits of VCS like short serum half-life (12 min), high dosing frequency (1.4 mg/m(2) per week for 4 weeks) and extensive protein binding (75%) limit the clinical potential of VCS in cancer therapy. In present investigation, injectable vincristine sulfate loaded dextran microspheres (VCS-Dextran-MSs) were prepared and amalgamated with chitosan-β-glycerophosphate gel (VCS-Dextran-MSs-Gel) to surmount the biopharmaceutical and pharmacokinetic limitations of VCS that consequently induced synergistic sustained release pattern of the drug. Particle size and zeta-potential of VCS-Dextran-MSs were measured to be 6.8 ± 2.4 μm and -18.3 ± 0.11 mV along with the encapsulation efficiency of about 60.4 ± 4.5%. Furthermore, VCS-Dextran-MSs and VCS-Dextran-MSs-Gel exhibited slow release pattern and 94.7% and 95.8% of the drug was released in 72 h and 720 h, respectively. Results from cell viability assay and pharmacokinetic as well as histopathological analysis in mice indicated that VCS-Dextran-MSs-Gel offers superior therapeutic potential and higher AUClast than VCS-Dextran-MSs and drug solution. In conclusion, VCS-Dextran-MSs-Gel warrants further preclinical tumor growth study to scale up the technology. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Optimal decentralized valley-filling charging strategy for electric vehicles

    International Nuclear Information System (INIS)

    Zhang, Kangkang; Xu, Liangfei; Ouyang, Minggao; Wang, Hewu; Lu, Languang; Li, Jianqiu; Li, Zhe

    2014-01-01

    Highlights: • An implementable charging strategy is developed for electric vehicles connected to a grid. • A two-dimensional pricing scheme is proposed to coordinate charging behaviors. • The strategy effectively works in decentralized way but achieves the systematic valley filling. • The strategy allows device-level charging autonomy, and does not require a bidirectional communication/control network. • The strategy can self-correct when confronted with adverse factors. - Abstract: Uncoordinated charging load of electric vehicles (EVs) increases the peak load of the power grid, thereby increasing the cost of electricity generation. The valley-filling charging scenario offers a cheaper alternative. This study proposes a novel decentralized valley-filling charging strategy, in which a day-ahead pricing scheme is designed by solving a minimum-cost optimization problem. The pricing scheme can be broadcasted to EV owners, and the individual charging behaviors can be indirectly coordinated. EV owners respond to the pricing scheme by autonomously optimizing their individual charge patterns. This device-level response induces a valley-filling effect in the grid at the system level. The proposed strategy offers three advantages: coordination (by the valley-filling effect), practicality (no requirement for a bidirectional communication/control network between the grid and EV owners), and autonomy (user control of EV charge patterns). The proposed strategy is validated in simulations of typical scenarios in Beijing, China. According to the results, the strategy (1) effectively achieves the valley-filling charging effect at 28% less generation cost than the uncoordinated charging strategy, (2) is robust to several potential affecters of the valley-filling effect, such as (system-level) inaccurate parameter estimation and (device-level) response capability and willingness (which cause less than 2% deviation in the minimal generation cost), and (3) is compatible with

  18. Recent developments in inorganically filled carbon nanotubes: successes and challenges

    Directory of Open Access Journals (Sweden)

    Ujjal K Gautam, Pedro M F J Costa, Yoshio Bando, Xiaosheng Fang, Liang Li, Masataka Imura and Dmitri Golberg

    2010-01-01

    Full Text Available Carbon nanotubes (CNTs are a unique class of nanomaterials that can be imagined as rolled graphene sheets. The inner hollow of a CNT provides an extremely small, one-dimensional space for storage of materials. In the last decade, enormous effort has been spent to produce filled CNTs that combine the properties of both the host CNT and the guest filling material. CNTs filled with various inorganic materials such as metals, alloys, semiconductors and insulators have been obtained using different synthesis approaches including capillary filling and chemical vapor deposition. Recently, several potential applications have emerged for these materials, such as the measurement of temperature at the nanoscale, nano-spot welding, and the storage and delivery of extremely small quantities of materials. A clear distinction between this class of materials and other nanostructures is the existence of an enormous interfacial area between the CNT and the filling matter. Theoretical investigations have shown that the lattice mismatch and strong exchange interaction of CNTs with the guest material across the interface should result in reordering of the guest crystal structure and passivation of the surface dangling bonds and thus yielding new and interesting physical properties. Despite preliminary successes, there remain many challenges in realizing applications of CNTs filled with inorganic materials, such as a comprehensive understanding of their growth and physical properties and control of their structural parameters. In this article, we overview research on filled CNT nanomaterials with special emphasis on recent progress and key achievements. We also discuss the future scope and the key challenges emerging out of a decade of intensive research on these fascinating materials.

  19. High Fill-Factor Transport Experiments on the HCX

    International Nuclear Information System (INIS)

    Prost, L R; Seidl, P A; Lund, S M

    2004-01-01

    Heavy-ion induction linacs have application as drivers for high energy density physics studies and ultimately as drivers for inertial fusion energy. Experiments on the High-Current Experiment (HCX) at LBNL explore heavy-ion beam transport at high fill factors (i.e., the ratio of the maximum transverse extent of the beam to the physical aperture). The fill factor has a large impact on the cost of multi-beam induction accelerators, the 80% fill factor compared with 60% would reduce the cost of an HIF driver by about 1/3. With a coasting low-emittance 1 MeV K + beam, transport through ten electrostatic quadrupoles was achieved at high beam fill factor (80%) without observed emittance growth and with little beam loss ((le) 1%), even though the initial beam distribution is neither ideal nor in thermal equilibrium, see Figure. While 10 quadrupoles are too few for settling questions of emittance evolution in a long system, they are very relevant for studying the rapid initial evolution of the emittance and beam profile that is expected in the front end of an accelerator. Studies at higher fill factors are planned, so that the failure mode can be established. Good envelope control was achieved, suggesting that, in a longer lattice of similar design, rematching only every ten lattice periods (at 80% fill factor) will be sufficient. Agreement was reached between an improved envelope model and the data. Improvements to the model are: realistic quadrupole fringe fields based on 3D field calculations; quadrupole E z from the 3D lattice structure and corresponding radial focusing force; and corrections due to the grounded slit plates of the intercepting diagnostics that short out the self-field of the beam near those plates. We also find that understanding and controlling the time dependence of the envelope parameters is critical to achieving high fill factors, notably because of the injector and matching section dynamics

  20. Do pharmacists have a right to refuse to fill prescriptions for abortifacient drugs?

    Science.gov (United States)

    Weinstein, B D

    1992-01-01

    Some pharmacists opposed to abortion on moral ground are concerned by having to fill prescriptions for abortifacient drugs like mifepristone (RU-486). The issue of the right of pharmacists to refuse to fill such prescriptions depends on the model of the physician-pharmacist-patient relationship. The libertarian model of pharmacy practice holds that physicians, pharmacists, and patients are bound only by the contract that they freely negotiate with one another, thus the pharmacist has no moral obligation to fill a prescription for mifepristone unless he or she has expressly contracted to do so. The American Pharmaceutical Association's 1981 Code of Ethics does not specify what a pharmacist ought to do in particular circumstances. The right to refuse is strongly supported by the principles of nonmaleficence and respect for autonomy. These are principles of the libertarian model of the pharmacist-patient relationship but are also present in the guild or societal models stressing the duty to avoid harming others. Justification for pharmacists right of refusal appeals to their autonomy rights as members of the moral community rather than the profession of pharmacy. Since the professional right to autonomy is not absolute, moral consideration circumscribe it: it is difficult to argue that a pharmacist who believes that homosexuality is immoral has the right to refuse to fill a prescription for AZT. Even if a person who presents such a prescription is homosexual there is no causal relationship between filling a prescription for AZT and participating in a homosexual act. At the opposite end the libertarians reject the notion of even a basic right to health care. A woman in the above situation would not have a right to the abortifacient drug, so a pharmacist has no duty to dispense it. According to the technician model of professionalism, the pharmacist's personal values do not matter, so a pharmacist has a duty to provide the service.