scholarly journals Clinical comparison of the stain removal efficacy of two air polishing powders

2017 ◽  
Vol 11 (03) ◽  
pp. 370-375
Author(s):  
Rosalin Hongsathavij ◽  
Yosvimol Kuphasuk ◽  
Kanyawat Rattanasuwan
Keyword(s):  
Grain Size ◽  
Sodium Bicarbonate ◽  
Patient Comfort ◽  
Patient Acceptance ◽  
Double Blind ◽  
Grain Sizes ◽  
Air Polishing ◽  
Clinical Comparison ◽  
Stain Removal ◽  
The Difference

ABSTRACT Objectives:Air polishing with sodium bicarbonate powders with a grain size of 40 μm is recommended for patient comfort. However, the efficacy of small grain size on stain removal has not been adequately studied. This study aimed to compare the stain removal efficacy of sodium bicarbonatepowders with grain sizes of 65 and 40 μm and to evaluate patient acceptance and operator opinion after using both air polishing powders. Materials and Methods: A double-blind, randomized, split-mouth study was conducted with 35 participants with moderate to heavy dental staining on both sides of the upper teeth. Removal of dental stains on the index teeth was performed using sodium bicarbonate powders with a grain size of either 65 or 40 μm. The time taken to completely remove all dental stains was recorded. After treatment, a questionnaire was used to evaluate patient acceptance and the operator's opinion.Results: The average time for the removal of all stains by powder was 4.5 ± 3.6 min with a grain size of 65 μm and 4.4 ± 3.8 min with a grain size of 40 μm. The difference in the average time between the two groups was not significant (P = 0.461). The operator's opinions of the two powders were identical, and patient acceptance did not differ significantly between the two types of powders.Conclusions: The 40 μm sodium bicarbonate powder removed dental stains as efficiently as the 65-μm powder. Powder handling and patient acceptance were comparable between grain sizes of 65 and 40 μm.

Environmental magnetism as a stream sediment tracer: an interpretation of the methodology and some case studies

Soil Research ◽  
1998 ◽  
Vol 36 (1) ◽  
pp. 167 ◽  
Author(s):  
R. H. Crockford ◽  
P. M. Fleming
Keyword(s):  
Grain Size ◽  
Case Studies ◽  
Environmental Magnetism ◽  
Extensive Discussion ◽  
Remanent Magnetisation ◽  
Grain Sizes ◽  
South Wales ◽  
Wide Range ◽  
River Confluences ◽  
The Difference

A comprehensive sediment sampling program was undertaken in the upper Molonglo catchment in south-eastern New South Wales to determine if mineral magnetics could be used to estimate sidestream contribution at river confluences in this environment. Some 12 confluences were examined over 1400 km 2 in 2 major basins and over 2 contrasting geological types. Sediment samples were divided into 7 size classes and the following magnetic properties measured: magnetic susceptibility at 2 frequencies, isothermal remanent magnetisation at 3 flux densities, and anhysteristic remanent magnetisation. The sidestream inputs were calculated for each particle size class from the range of magnetic parameters. Significant discrepancies and differences appeared in the resultant sidestream inputs, and this paper outlines the conclusions as to the reliability of the different analytical procedures. It is shown that both the concentration and magnetic grain size of ferrimagnetic minerals in the sediments must be taken into account. Where the difference in magnetic grain size between the upstream and sidestream sediments is small, the use of parameter crossplots or bulked magnetic ratios is generally not appropriate. The use of mass (concentration) magnetic values may be better. The difference in the demands of the crossplots and mass values methods is that crossplots require a wide range of mass magnetic concentrations in each branch, with the upstream and sidestream sediments having different magnetic grain sizes, whereas the mass values procedure does best with a very limited (but different) range of concentrations at the upstream and sidestream branches, but similar magnetic grain sizes. This paper provides an extensive discussion of the estimation technique using different parameter combinations, and uses 3 contrasting confluences as case studies.

Electroplated Cu Recrystallization in Damascene Structures at Elevated Temperatures

1999 ◽  
Vol 564 ◽  
Author(s):  
Qing-Tang Jiang ◽  
Michael E. Thomas ◽  
Gennadi Bersuker ◽  
Brendan Foran ◽  
Robert Mikkola ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Grain Size ◽  
Film Thickness ◽  
Grain Growth ◽  
Elevated Temperatures ◽  
Retardation Effect ◽  
Cu Films ◽  
Grain Sizes ◽  
Geometrical Constraints ◽  
The Difference

AbstractTransformations in electroplated Cu films from a fine to course grain crystal structure (average grain sizes went from ∼0.1 µm to several microns) were observed to strongly depend on film thickness and geometry. Thinner films underwent much slower transformations than thicker ones. A model is proposed which explains the difference in transformation rates in terms of the physical constraint experienced by the film since grain growth in thinner films is limited by film thickness. Geometrical constraints imposed by trench and via structures appear to have an even greater retardation effect on the grain growth. Experimental observations indicate that it takes much longer for Cu in damascene structures to go through grain size transformations than blanket films.

Influence of Grain Size and Grain Boundary of Workpiece on Micro EDM

2014 ◽  
Vol 941-944 ◽  
pp. 2116-2120 ◽  
Author(s):  
Qing Yu Liu ◽  
Qin He Zhang ◽  
Jian Hua Zhang ◽  
Min Zhang
Keyword(s):  
Grain Size ◽  
Grain Boundary ◽  
Micro Edm ◽  
Test Results ◽  
Machining Performance ◽  
Grain Sizes ◽  
Stainless Steel 304 ◽  
Micro Holes ◽  
The Difference ◽  
Micro Features

Micro EDM is used to machine micro features which are of the same size order as material microstructure of workpiece. Due to the difference of the thermal properties between the crystal grain and grain boundary, the machining performance of micro EDM varies with the crystal grain sizes of workpiece. This paper investigated on the influence of grain size and grain boundary on the machining performance of micro EDM. By drilling micro holes on two pieces of stainless steel 304 (SUS 304) which are different in grain sizes, test results revealed that the characteristics of micro EDM is influenced by grain sizes of workpiece materials significantly.

scholarly journals Joining Of Green Body And Dense Substrate For Indium Tin Oxide Under Uniaxial Pressure In An Open Condition

2015 ◽  
Vol 60 (2) ◽  
pp. 1209-1212
Author(s):  
G.-S. Moon ◽  
T.-J. Chung ◽  
S.-H. Yang ◽  
G.-S. Hong ◽  
K.-S. Oh
Keyword(s):  
Grain Size ◽  
Tin Oxide ◽  
Indium Tin Oxide ◽  
Transparent Conducting Oxide ◽  
Theoretical Density ◽  
Uniaxial Pressure ◽  
Green Body ◽  
Grain Sizes ◽  
Transparent Conducting ◽  
The Difference

Abstract The green body and dense substrate of indium tin oxide was joined by uniaxially pressing at 0.3 MPa at 1300°C to test the restoring of the eroded part of transparent conducting oxide target. The green body was sintered to 98% of theoretical density under the suppression of shrinkage along the boundary below 5%. The boundary between two parts was free of pore but could be recognized from the difference in grain sizes. The joined part had the virtually same density with the substrate, but the grain size was less than one fifth compared with that of substrate.

Sodium bicarbonate in 5% dextrose: can clinicians tell the difference?

2020 ◽  
Vol 22 (1) ◽  
pp. 80-82
Author(s):  
Briony Jude ◽  
◽  
Thummaporn Naorungroj ◽  
Ary Serpa Neto ◽  
Tomoko Fujii ◽  
...  
Keyword(s):  
Metabolic Acidosis ◽  
Sodium Bicarbonate ◽  
Randomised Controlled Trials ◽  
Controlled Trials ◽  
Double Blind ◽  
Icu Patients ◽  
Bicarbonate Therapy ◽  
The Difference ◽  
Randomised Controlled ◽  
Intravenous Sodium

BACKGROUND: Due to the lack of double-blind randomised controlled trials, the true effect of intravenous sodium bicarbonate therapy in ICU patients with metabolic acidosis remains unclear. METHODS: We diluted 100 mL 8.4% sodium bicarbonate in 150 mL 5% dextrose (D5W) within a 250 mL polyolefin bag after removing 100 mL. We asked ICU clinicians to inspect a 250 mL bag containing sodium bicarbonate or a 250 mL bag where 100 mL of D5W had been removed and then returned. The bags were attached to intravenous giving sets. We asked participants to identify the contents of the bags. RESULTS: Among 60 participants (39 nursing staff [65%], 20 medical staff [33.3%] and one pharmacist), 36 (60%) answered correctly. The Cohen κ for agreement between test bag content and participants' answers was 0.20 (95% CI, −0.05 to 0.45; P = 0.12), implying the answers were correct by chance. In the group of 28 participants who indicated they used a clue to help them decide their answer, 15 (53.6%) answered correctly, whereas in the remainder (n = 32), 21 (65.6%) answered correctly (P = 0.49). CONCLUSION: When 100 mL of 8.4% sodium bicarbonate were diluted in 150 mL of D5W within a 250 mL polyolefin bag, clinicians were unable to correctly identify the contents of the bags. Our findings imply that sodium bicarbonate therapy can be successfully blinded.

The Effects of a Caffeine Placebo and Experimenter Expectation on Blood Pressure, Heart Rate, Well-Being, and Cognitive Performance

2001 ◽  
Vol 6 (1) ◽  
pp. 15-25 ◽  
Author(s):  
Harald Walach ◽  
Stefan Schmidt ◽  
Yvonne-Michelle Bihr ◽  
Susanne Wiesch
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Cognitive Task ◽  
Well Being ◽  
Control Group ◽  
Double Blind ◽  
Main Effect ◽  
The Difference ◽  
Being There ◽  
To Receive

We studied the effect of experimenter expectations and different instructions in a balanced placebo design. 157 subjects were randomized into a 2 × 4 factorial design. Two experimenters were led to expect placebos either to produce physiological effects or not (pro- vs. antiplacebo). All subjects except a control group received a caffeine placebo. They were either made to expect coffee, no coffee, or were in a double-blind condition. Dependent measures were blood pressure, heart rate, well-being, and a cognitive task. There was one main effect on the instruction factor (p = 0.03) with the group “told no caffeine” reporting significantly better well-being. There was one main effect on the experimenter factor with subjects instructed by experimenter “proplacebo” having higher systolic blood pressure (p = 0.008). There was one interaction with subjects instructed by experimenter “proplacebo” to receive coffee doing worse in the cognitive task than the rest. Subjects instructed by experimenter “antiplacebo” were significantly less likely to believe the experimental instruction, and that mostly if they had been instructed to receive coffee. Contrary to the literature we could not show an effect of instruction, but there was an effect of experimenters. It is likely, however, that these experimenter effects were not due to experimental manipulations, but to the difference in personalities.

scholarly journals Efficacy and Safety of a 3-Antigen (Pre-S1/Pre-S2/S) Hepatitis B Vaccine: Results of a Phase 3 Randomized Clinical Trial in the Russian Federation

2020 ◽  
Author(s):  
Elena V Esaulenko ◽  
Aleksey A Yakovlev ◽  
Genady A Volkov ◽  
Anastasia A Sukhoruk ◽  
Kirill G Surkov ◽  
...  
Keyword(s):  
Hepatitis B ◽  
Geometric Mean ◽  
Serious Adverse Events ◽  
Double Blind ◽  
Antigen Vaccine ◽  
Single Antigen ◽  
Antibody Titers ◽  
The Russian Federation ◽  
The Difference ◽  
Mean Concentration

Abstract Background This study compares the immunogenicity and safety of a 3-antigen (S/pre-S1/pre-S2) hepatitis B (HepB) vaccine (3AV), to a single antigen vaccine (1AV) in adults to support the registration of 3AV in Russia. Methods We conducted a randomized, double-blind, comparative study of 3-dose regimens of 3AV (10 μg) and 1AV (20 µg) in adults aged 18–45 years. We evaluated immunogenicity based on hepatitis B surface (HBs) antibody titers at days 1, 28, 90, 180, and 210, adverse and serious adverse events (SAEs) to study day 210. The primary outcome was based on the difference in rates of seroconversion at day 210 (lower bound 95% confidence interval [CI]: > − 4%). Secondary outcomes were seroprotection rates (SPR), defined as anti-HBs ≥10 mIU/mL and anti-HBs geometric mean concentration (GMC). Results Rate of seroconversion in 3AV (100%) was noninferior to 1AV (97.9%) at study day 210 (difference: 2.1%, 95% CI: −2.0, 6.3%]) but significantly higher at study day 28. SPR at study day 210 was >97% in both arms. Anti-HBs titers were significantly higher at study days 90 (P = .001) and 180 (P = .0001) with 3AV. Sex, age, and body mass index (BMI) had no impact on anti-HBs titers. The rates of local reactions related to vaccination were similar between vaccine arms (3AV vs 1AV) after the first (30% vs 18.8%, P = .15), second (20.0% vs 14.6%, P = .33), and third vaccination (14.9% vs 23.4%, P = .22). No SAEs were reported. Conclusions 3AV was noninferior to 1AV. 3AV induced high SPR, and there were no safety concerns. Clinical Trials Registration. NCT04209400.

341 Acute effects of seltorexant, a selective orexin-2 antagonist (JNJ- 42847922), on driving after bedtime administration

SLEEP ◽  
2021 ◽  
Vol 44 (Supplement_2) ◽  
pp. A136-A136
Author(s):  
S Brooks ◽  
R G J A Zuiker ◽  
G E Jacobs ◽  
I Kezic ◽  
A Savitz ◽  
...  
Keyword(s):  
Postural Stability ◽  
Driving Simulator ◽  
Motor Vehicle ◽  
Subjective Effects ◽  
Driving Ability ◽  
Post Dose ◽  
Double Blind ◽  
Increased Risk ◽  
Subjective Sleepiness ◽  
The Difference

Abstract Introduction Seltorexant (JNJ-42847922), a potent and selective antagonist of the human orexin-2 receptor, is being developed for the treatment of major depressive disorder. Seltorexant also has sleep-promoting properties. Investigating the effects of sleep-promoting medications on driving is important because some of these agents (e.g. GABAA receptor agonists) may be associated with increased risk of motor vehicle accidents. We evaluated the effect of seltorexant on driving after forced awakening at night, using a validated driving simulator. Methods This double-blind, placebo and active-controlled, randomized, 3-way cross-over study was conducted in 18 male and 18 female healthy subjects. All subjects received seltorexant 40 mg, zolpidem 10 mg, or placebo 15 minutes before bedtime. Eighteen subjects were awakened at 2- and 6-hours post-dose, and the other 18 at 4- and 8-hours post-dose. At those timepoints, pharmacokinetics, objective (standard deviation of the lateral position [SDLP]) and subjective effects (using Perceived Driving Quality and Effort Scales) on driving ability, postural stability and subjective sleepiness were assessed. Results For seltorexant, the SDLP difference from placebo (95% confidence interval) at 2-, 4-, 6- and 8-hours post-dose was 3.9 cm (1.26, 6.60), 0.9 cm (-1.08, 2.92), 1.1 cm (-0.42, 2.63), and 0.6 cm (-2.75, 1.55), respectively vs. 9.6 cm (6.97, 12.38), 6.6 cm (3.53, 9.60), 4.7 cm (1.46, 7.85), and 1.3cm (-1.16, 3.80), respectively for zolpidem. The difference from placebo was significant at 2-hours after taking seltorexant, while the difference from placebo was significant at 2, 4 and 6-hours after zolpidem. Subjective driving quality was decreased for both drugs at all time points and driving effort was increased up to 4-hours post-dose for both medications. Subjective sleepiness showed a significant increase compared to placebo 2- and 4-hours after administration of either drug. Postural stability was decreased up to 2-hours after administration of seltorexant, and up to 4-hours after administration of zolpidem. Conclusion Compared to zolpidem, objective effects on driving performance were more transient after seltorexant administration and largely normalized by 4–6 hours post-dose. Support (if any) This work was sponsored by Janssen R&D.

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