scholarly journals Air particulate concentration during orthodontic procedures: a pilot study

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Inmaculada Martín-Quintero ◽  
Alberto Cervera-Sabater ◽  
Víctor Tapias-Perero ◽  
Iván Nieto-Sánchez ◽  
Javier de la Cruz-Pérez
Keyword(s):  
Pilot Study ◽  
Relative Humidity ◽  
High Capacity ◽  
Statistical Modelling ◽  
Particle Dispersion ◽  
Clinical Activity ◽  
Regression Equations ◽  
Dental Procedures ◽  
The Moment ◽  
Number Of Particles

Abstract Background This study evaluates the particle dispersion involved in dental procedures carried out during orthodontic treatments. Variants such as temperature and relative humidity in the dental cabinet were considered. Methods Using a particle counter, a pilot study was conducted, in which 98 consecutive recordings were made during appointments of patients undergoing orthodontic treatments. Temperature, relative humidity and particles present at the beginning (AR) and during the appointment (BR) were recorded. A control record (CR) of temperature, relative humidity and particles present was made before the start of the clinical activity. In addition to conventional statistics, differential descriptive procedures were used to analyse results, and the influence of relative humidity on particle concentration was analysed by statistical modelling with regression equations. Results The number of particles present, regardless of their size, was much higher in AR than in CR (p < .001). The same was true for relative humidity and ambient temperature. The relationship between relative humidity and particle number was determined to be exponential. Limitations of the study The limitations are associated with sample size, environmental conditions of the room and lack of discrimination among the procedures performed. Conclusions This pilot study shows that from the moment a patient enters a dental office, a large number of additional particles are generated. During treatment, the number of particles of 0.3 microns—which have a high capacity to penetrate the respiratory tract-increases. Moreover, a relationship between relative humidity and particle formation is observed. Further studies are needed.

scholarly journals Air Particulate Concentration in Dental Surgery During Orthodontic Procedures: A Pilot Study

2021 ◽  
Author(s):  
Inmaculada Martín-Quintero ◽  
Alberto Cervera-Sabater ◽  
Víctor Tapias-Perero ◽  
Iván Nieto-Sánchez ◽  
Javier de la Cruz-Pérez
Keyword(s):  
Pilot Study ◽  
Relative Humidity ◽  
High Capacity ◽  
Statistical Modelling ◽  
Particle Dispersion ◽  
Clinical Activity ◽  
Regression Equations ◽  
Dental Surgery ◽  
Dental Procedures ◽  
Number Of Particles

Abstract Background: This study evaluates the particle dispersion involved in dental procedures carried out during orthodontic treatments. Variants such as temperature and relative humidity in the dental cabinet were considered. Methods: Using a particle counter, a pilot study was conducted, in which 98 consecutive recordings were made during appointments of patients undergoing orthodontic treatments. Temperature, relative humidity and particles present at the beginning (AR) and during the appointment (BR) were recorded. A control record (CR) of temperature, relative humidity and particles present was made before the start of the clinical activity. In addition to conventional statistics, differential descriptive procedures were used to analyse results, and the influence of relative humidity on particle concentration was analysed by statistical modelling with regression equations. Results: The number of particles present, regardless of their size, was much higher in AR than in CR (p<.001). The same was true for relative humidity and ambient temperature. The relationship between relative humidity and particle number was determined to be exponential. Limitations of the study: The limitations are associated with sample size, environmental conditions of the room and lack of discrimination among the procedures performed. Conclusions: This pilot study shows that from the moment a patient enters a dental office, a large number of additional particles are generated. During treatment, the number of particles of 0.3 microns – which have a high capacity to penetrate the respiratory tract – increases. Moreover, a relationship between relative humidity and particle formation is observed. Further studies are needed.

scholarly journals Period-Life of a Branching Process with Migration and Continuous Time

Mathematics ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 868
Author(s):  
Khrystyna Prysyazhnyk ◽  
Iryna Bazylevych ◽  
Ludmila Mitkova ◽  
Iryna Ivanochko
Keyword(s):  
Random Process ◽  
Generating Function ◽  
Continuous Time ◽  
Branching Process ◽  
Probability Generating Function ◽  
Time Interval ◽  
The Moment ◽  
First Time ◽  
Critical Branching Process ◽  
Number Of Particles

The homogeneous branching process with migration and continuous time is considered. We investigated the distribution of the period-life τ, i.e., the length of the time interval between the moment when the process is initiated by a positive number of particles and the moment when there are no individuals in the population for the first time. The probability generating function of the random process, which describes the behavior of the process within the period-life, was obtained. The boundary theorem for the period-life of the subcritical or critical branching process with migration was found.

A Pilot Study Evaluating 99mTc-anti-TNF-alpha Scintigraphy in Graves' Ophtalmopathy Patients with Different Clinical Activity Score

2013 ◽  
Vol 45 (10) ◽  
pp. 765-768 ◽  
Author(s):  
E. Rebelo Pinto ◽  
F. Lopes ◽  
S. de Souza ◽  
L. da Fonseca ◽  
M. Vaisman ◽  
...  
Keyword(s):  
Pilot Study ◽  
Activity Score ◽  
Tnf Alpha ◽  
Clinical Activity ◽  
Clinical Activity Score

scholarly journals IDEAL-MODIFIED BOSONIC GAS TRAPPED IN AN ARBITRARY THREE-DIMENSIONAL POWER-LAW POTENTIAL

2012 ◽  
Vol 27 (31) ◽  
pp. 1250181 ◽  
Author(s):  
E. CASTELLANOS ◽  
C. LÄMMERZAHL
Keyword(s):  
Dispersion Relation ◽  
Power Law ◽  
Three Dimensional ◽  
Particle Dispersion ◽  
Einstein Condensate ◽  
Gravity Models ◽  
Condensation Temperature ◽  
Bose Einstein Condensate ◽  
Bose Einstein ◽  
Number Of Particles

We analyze the effects caused by an anomalous single-particle dispersion relation suggested in several quantum-gravity models, upon the thermodynamics of a Bose–Einstein condensate trapped in a generic three-dimensional power-law potential. We prove that the shift in the condensation temperature, caused by a deformed dispersion relation, described as a non-trivial function of the number of particles and the shape associated to the corresponding trap, could provide bounds for the parameters associated to such deformation. In addition, we calculate the fluctuations in the number of particles as a criterium of thermodynamic stability for these systems. We show that the apparent instability caused by the anomalous fluctuations in the thermodynamic limit can be suppressed considering the lowest energy associated to the system in question.

scholarly journals Statistical Modelling of Temperature and Moisture Uptake of Biochars Exposed to Selected Relative Humidity of Air

2018 ◽  
Vol 5 (1) ◽  
pp. 13
Author(s):  
Luciane Bastistella ◽  
Patrick Rousset ◽  
Antonio Aviz ◽  
Armando Caldeira-Pires ◽  
Gilles Humbert ◽  
...  
Keyword(s):  
Relative Humidity ◽  
Statistical Modelling ◽  
Moisture Uptake

A Pilot Study Comparing Pedometer Counts with Reported Physical Activity in Elementary Schoolchildren

2004 ◽  
Vol 16 (4) ◽  
pp. 355-367 ◽  
Author(s):  
Greet Cardon ◽  
Ilse De Bourdeaudhuij
Keyword(s):  
Physical Activity ◽  
Pilot Study ◽  
Vigorous Physical Activity ◽  
Step Count ◽  
Regression Equations ◽  
Moderate Correlation ◽  
Daily Step ◽  
Step Counts ◽  
Daily Step Count

In this study pedometer counts were recorded for 6 consecutive days for 92 children (mean age = 9.6 years; range 6.5–12.7) and were compared with the number of minutes per day in which the participants engaged in moderate-to-vigorous physical activity (MVPA). Diaries filled out with the assistance of one of the children’s parents were used to determine minutes of MVPA. The average daily step count was significantly higher in boys than in girls, although the average daily MVPA engagement in minutes did not vary significantly between genders. Based on the regression equations, 60 min of MVPA was equivalent to 15,340 step counts in boys, 11,317 step counts in girls, and 13,130 step counts when results for both genders were combined. A moderate correlation (r = .39, p < .001) was found between pedometer step counts and reported minutes of MVPA. According to the present study findings, however, predictions and promotion of daily MVPA engagement in children based on pedometer counts per day should be made with caution.

scholarly journals The Cupola: An Additional Layer of Protection for Providers Working in the Oropharyngeal Region

2021 ◽  
Author(s):  
Alessandro Villa ◽  
Marlene Grenon
Keyword(s):  
Pilot Study ◽  
Personal Protective Equipment ◽  
Airborne Particles ◽  
Protective Equipment ◽  
Additional Layer ◽  
Dental Procedures ◽  
The Mean ◽  
Mechanical Barrier

Abstract ObjectivesTo reduce the spread of the infection, especially during aerosol generating procedures, we invented “The Cupola”, a shield that creates a mechanical barrier around the patient’s head and body. With this pilot study we aimed to assess the effectiveness of an additional layer of protection (The Cupola) developed for providers working in the oropharyngeal region.ResultsThe mean number of 0.3 μm particles with no Cupola was 3777 (SD: ±556), with The Cupola was 2068 (SD: ±1468) and with the Cupola and Drape was 2031 (SD: ±1108) (p<0.015). The mean number of 0.5 μm airborne particles with no Cupola was 65 (SD: ±7), with The Cupola was 29 (SD: ±28) and with the Cupola and Drape was 28 (SD: ±23) (p<0.05). Results showed a significant reduction of aerosols generated during simulated dental procedures when the Cupola was used. The Cupola offers an extra layer of protection in addition to the recommended personal protective equipment.

scholarly journals Determination of relative contribution of different meteorological elements on evaporation

MAUSAM ◽  
2021 ◽  
Vol 50 (4) ◽  
pp. 365-374
Author(s):  
A. CHOWDHURY ◽  
H. P. DAS ◽  
S. D. GAIKWAD
Keyword(s):  
Relative Humidity ◽  
Surface Wind ◽  
Maximum Temperature ◽  
New Delhi ◽  
Regression Equations ◽  
Weather Factors ◽  
Relative Contribution ◽  
Daily Data ◽  
Radiation Maximum ◽  
June July

The present study deals with influence of radiation, maximum temperature, hours of bright sunshine, relative humidity and surface wind on evaporation at Calcutta, Pune and New Delhi. Daily data from 1991-94 of January, May, June, July and October have been utilized. Direct and indirect influence of the weather factors have been determined through "path analysis" and discussed. Multiple regression equations have also been developed with evaporation as the dependent variable and the above five weather parameters as independent variables.   The results reveal that radiation and maximum temperature are the two most important parameters which enhance evaporation. Most of their effect is direct though in some cases their interaction with relative humidity or wind also contribute significantly to evaporation. Humidity and surface wind, generally, do not significantly contribute directly to evaporation; their effect is manifested through interaction with maximum temperature, indirectly.

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