scholarly journals A novel dental biosafety device to control the spread of potentially contaminated dispersion particles from dental ultrasonic tips

PLoS ONE ◽  
2021 ◽  
Vol 16 (2) ◽  
pp. e0247029
Author(s):  
Victor Angelo Martins Montalli ◽  
Aguinaldo Silva Garcez ◽  
Laís Viana Canuto de Oliveira ◽  
Marcelo Sperandio ◽  
Marcelo Henrique Napimoga ◽  
...  
Keyword(s):  
Standard Deviation ◽  
Lactobacillus Casei ◽  
Dispersion Model ◽  
Dental Practice ◽  
Clinical Procedures ◽  
The Us ◽  
The Mean ◽  
Petri Dishes ◽  
Spray Control ◽  
Dental Environment

Strategies to return to dental practice in pandemic times is a new challenge due to the generation and spread of potentially contaminated dispersion particles (PCDP) that may contain the SARS-CoV-2, the etiological factor of the COVID-19 disease. Due to the significant dispersion of PCDP in the dental environment, the use of equipment such as ultrasonic tips have been inadvisable during the pandemic. Several clinical procedures, however, benefit from the use of such equipment. Thus, using a microbial dispersion model of PCDP, the aim of this study was to compare the dispersion caused by the dental drill (DD) an ultrasonic tip (UT) alone and the UT coupled with a Spray control (SC) device. The DD, UT (with or without the SC) were activated for one minute having had the water from the reservoir replaced with a suspension of Lactobacillus casei Shirota (1.5 x 108 CFU/mL). Petri dishes containing MRS agar were positioned at 50cm, 100cm and 150cm from the headrest of the dental chair at different angles (0 degree and 90 degrees). At 50 cm, the mean CFU (standard deviation) of L. casei Shirota was 13554.60 (4071.03) for the DD, 286.67 (73.99) for the US (97.89% reduction), and 4.5 (0.58) CFU for the UT-SC (p < 0.0001), establishing a further 98.43% reduction between UT and UT with SC. The UT with SC model proved effective in reducing dispersion from the UT, endorsing its use as an additional strategy to reduce PCDP in the dental environment in times of pandemic.

scholarly journals Individual biosafety barrier in dentistry: an alternative in times of covid-19. Preliminary study

2020 ◽  
Vol 68 ◽  
Author(s):  
Victor Angelo Martins MONTALLI ◽  
Aguinaldo Silva GARCEZ ◽  
Gabriel Angelo Martins MONTALLI ◽  
Fabiana Mantovani Gomes FRANÇA ◽  
Selly Sayuri SUZUKI ◽  
...  
Keyword(s):  
Lactobacillus Casei ◽  
Dispersion Model ◽  
Dental Practice ◽  
Viable Option ◽  
Dental Drill ◽  
Lactobacillus Casei Shirota ◽  
Pvc Film ◽  
The Mean ◽  
Preliminary Study ◽  
The Individual

ABSTRACT The return to dental practice in pandemic times is a new challenge due to the generation and dispersion of droplets and aerosols that may contain the SARS-CoV-2 virus, the etiological agent of covid-19. In the last months some droplet and aerosol containment strategies have been circulating on the internet, however, until now there is no evidence in the literature to prove the effectiveness of such barriers. Thus, using a microbial dispersion model with the fast handpiece, the aim of this preliminary study was to compare the dispersion caused by the the dental drill (DD) alone or in association with an individual biosafety barrier (IDBD / DD), which consisted of a layer of PVC film combined to a layer of polypropylene mounted on a frame. The dental drill was activated for one minute having had the water from the reservoir been replaced with a suspension of Lactobacillus casei Shirota. Petri dishes containing MRS agar were positioned at 50, 100 and 150 cm from the headboard of the dental chair at different angles (90 and 0 degrees). At 50 cm, the mean (standard deviation) of L. casei Shirota for DD was 13,554.59 (493.48) CFU, while for IDBD / DD was 570.67 (60.54) CFU (p <0.0001), establishing a 96% reduction. Considering these preliminary results, the individual biosafety barrier proved effective in reducing dispersion from the dental drill in this study model, which suggests that this barrier may be a viable option to optimize biosafety in the dental environment.

Relation of Statistically Significant, Abnormal, and Typical WAIS-R VIQ-PIQ Discrepancies to Full Scale IQs

2000 ◽  
Vol 16 (2) ◽  
pp. 107-114 ◽  
Author(s):  
Louis M. Hsu ◽  
Judy Hayman ◽  
Judith Koch ◽  
Debbie Mandell
Keyword(s):  
Graphical Method ◽  
The United States ◽  
Full Scale ◽  
True Score ◽  
Absolute Value ◽  
Normative Population ◽  
The Us ◽  
The Mean ◽  
And Performance ◽  
Quadratic Models

Summary: In the United States' normative population for the WAIS-R, differences (Ds) between persons' verbal and performance IQs (VIQs and PIQs) tend to increase with an increase in full scale IQs (FSIQs). This suggests that norm-referenced interpretations of Ds should take FSIQs into account. Two new graphs are presented to facilitate this type of interpretation. One of these graphs estimates the mean of absolute values of D (called typical D) at each FSIQ level of the US normative population. The other graph estimates the absolute value of D that is exceeded only 5% of the time (called abnormal D) at each FSIQ level of this population. A graph for the identification of conventional “statistically significant Ds” (also called “reliable Ds”) is also presented. A reliable D is defined in the context of classical true score theory as an absolute D that is unlikely (p < .05) to be exceeded by a person whose true VIQ and PIQ are equal. As conventionally defined reliable Ds do not depend on the FSIQ. The graphs of typical and abnormal Ds are based on quadratic models of the relation of sizes of Ds to FSIQs. These models are generalizations of models described in Hsu (1996) . The new graphical method of identifying Abnormal Ds is compared to the conventional Payne-Jones method of identifying these Ds. Implications of the three juxtaposed graphs for the interpretation of VIQ-PIQ differences are discussed.

At Least One Standard Deviation Above the Mean

1969 ◽  
Vol 14 (9) ◽  
pp. 470-471
Author(s):  
M. DAVID MERRILL
Keyword(s):  
Standard Deviation ◽  
The Mean

The Estimation of Blood Platelet Survival

1972 ◽  
Vol 28 (03) ◽  
pp. 447-456 ◽  
Author(s):  
E. A Murphy ◽  
M. E Francis ◽  
J. F Mustard
Keyword(s):  
Standard Deviation ◽  
Least Squares ◽  
Experimental Error ◽  
Blood Platelet ◽  
Least Squares Estimation ◽  
Systematic Relationship ◽  
Platelet Survival ◽  
The Mean ◽  
Normally Distributed

SummaryThe characteristics of experimental error in measurement of platelet radioactivity have been explored by blind replicate determinations on specimens taken on several days on each of three Walker hounds.Analysis suggests that it is not unreasonable to suppose that error for each sample is normally distributed ; and while there is evidence that the variance is heterogeneous, no systematic relationship has been discovered between the mean and the standard deviation of the determinations on individual samples. Thus, since it would be impracticable for investigators to do replicate determinations as a routine, no improvement over simple unweighted least squares estimation on untransformed data suggests itself.

PENGARUH PENDIDIKAN KESEHATAN REPRODUKSI PADA PEER GROUP (TEMAN SEBAYA) TERHADAP PENGETAHUAN DAN PERSEPSI REMAJA TENTANG PENDEWASAAN USIA PERKAWINAN DI SMA NEGERI 1 KECAMATAN NAMORAMBE KAB. DELI SERDANG 2018

2020 ◽  
Vol 1 (2) ◽  
pp. 56-66
Author(s):  
Irma Linda
Keyword(s):  
Standard Deviation ◽  
Health Education ◽  
Reproductive Health ◽  
Peer Group ◽  
Peer Groups ◽  
A Value ◽  
Significant Difference ◽  
Reproductive Health Education ◽  
The Mean ◽  
Adolescent Perceptions

Background: Early marriages are at high risk of marital failure, poor family quality, young pregnancies at risk of maternal death, and the risk of being mentally ill to foster marriage and be responsible parents. Objective: To determine the effect of reproductive health education on peer groups (peers) on the knowledge and perceptions of adolescents about marriage age maturity. Method: This research uses the Quasi experimental method with One group pre and post test design, conducted from May to September 2018. The statistical analysis used in this study is a paired T test with a confidence level of 95% (α = 0, 05). Results: There is an average difference in the mean value of adolescent knowledge between the first and second measurements is 0.50 with a standard deviation of 1.922. The mean difference in mean scores of adolescent perceptions between the first and second measurements was 4.42 with a standard deviation of 9.611. Conclusion: There is a significant difference between adolescent knowledge on the pretest and posttest measurements with a value of P = 0.002, and there is a significant difference between adolescent perceptions on the pretest and posttest measurements with a value of p = 0.001. Increasing the number of facilities and facilities related to reproductive health education by peer groups (peers) in adolescents is carried out on an ongoing basis at school, in collaboration with local health workers as prevention of risky pregnancy.

Regularity and latency of units in ventral cochlear nucleus: implications for unit classification and generation of response properties

1988 ◽  
Vol 60 (1) ◽  
pp. 1-29 ◽  
Author(s):  
E. D. Young ◽  
J. M. Robert ◽  
W. P. Shofner
Keyword(s):  
Standard Deviation ◽  
Cochlear Nucleus ◽  
Interspike Interval ◽  
Rate Adaptation ◽  
Stellate Cells ◽  
Instantaneous Rate ◽  
Ventral Cochlear Nucleus ◽  
Bushy Cell ◽  
Low Pass ◽  
The Mean

1. The responses of neurons in the ventral cochlear nucleus (VCN) of decerebrate cats are described with regard to their regularity of discharge and latency. Regularity is measured by estimating the mean and standard deviation of interspike intervals as a function of time during responses to short tone bursts (25 ms). This method extends the usual interspike-interval analysis based on interval histograms by allowing the study of temporal changes in regularity during transient responses. The coefficient of variation (CV), equal to the ratio of standard deviation to mean interspike interval, is used as a measure of irregularity. Latency is measured as the mean and standard deviation of the latency of the first spike in response to short tone bursts, with 1.6-ms rise times. 2. The regularity and latency properties of the usual PST histogram response types are shown. Five major PST response type classes are used: chopper, primary-like, onset, onset-C, and unusual. The presence of a prepotential in a unit's action potentials is also noted; a prepotential implies that the unit is recorded from a bushy cell. 3. Units with chopper PST histograms give the most regular discharge. Three varieties of choppers are found. Chop-S units (regular choppers) have CVs less than 0.35 that are approximately constant during the response; chop-S units show no adaptation of instantaneous rate, as measured by the inverse of the mean interspike interval. Chop-T units have CVs greater than 0.35, show an increase in irregularity during the response and show substantial rate adaptation. Chop-U units have CVs greater than 0.35, show a decrease in irregularity during the response, and show a variety of rate adaptation behaviors, including negative adaptation (an increase in rate during a short-tone response). Irregular choppers (chop-T and chop-U units) rarely have CVs greater than 0.5. Choppers have the longest latencies of VCN units; all three groups have mean latencies at least 1 ms longer than the shortest auditory nerve (AN) fiber mean latencies. 4. Chopper units are recorded from stellate cells in VCN (35, 42). Our results for chopper units suggest a model for stellate cells in which a regularly firing action potential generator is driven by the summation of the AN inputs to the cell, where the summation is low-pass filtered by the membrane capacitance of the cell.(ABSTRACT TRUNCATED AT 400 WORDS)

scholarly journals Blood Oxygenation Level Dependent Magnetic Resonance Imaging (MRI), Dynamic Contrast Enhanced MRI and Diffusion Weighted MRI for Benign and Malignant Breast Cancer Discrimination: A Preliminary Experience

Cancers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 2421
Author(s):  
Roberta Fusco ◽  
Vincenza Granata ◽  
Mauro Mattace Raso ◽  
Paolo Vallone ◽  
Alessandro Pasquale De Rosa ◽  
...  
Keyword(s):  
Standard Deviation ◽  
Univariate Analysis ◽  
Mean Value ◽  
Blood Oxygenation ◽  
Breast Lesions ◽  
Dce Mri ◽  
Malignant Lesions ◽  
The Mean ◽  
And Diffusion ◽  
Skewness And Kurtosis

Purpose. To combine blood oxygenation level dependent magnetic resonance imaging (BOLD-MRI), dynamic contrast enhanced MRI (DCE-MRI), and diffusion weighted MRI (DW-MRI) in differentiation of benign and malignant breast lesions. Methods. Thirty-seven breast lesions (11 benign and 21 malignant lesions) pathologically proven were included in this retrospective preliminary study. Pharmaco-kinetic parameters including Ktrans, kep, ve, and vp were extracted by DCE-MRI; BOLD parameters were estimated by basal signal S0 and the relaxation rate R2*; and diffusion and perfusion parameters were derived by DW-MRI (pseudo-diffusion coefficient (Dp), perfusion fraction (fp), and tissue diffusivity (Dt)). The correlation coefficient, Wilcoxon-Mann-Whitney U-test, and receiver operating characteristic (ROC) analysis were calculated and area under the ROC curve (AUC) was obtained. Moreover, pattern recognition approaches (linear discrimination analysis and decision tree) with balancing technique and leave one out cross validation approach were considered. Results. R2* and D had a significant negative correlation (−0.57). The mean value, standard deviation, Skewness and Kurtosis values of R2* did not show a statistical significance between benign and malignant lesions (p > 0.05) confirmed by the ‘poor’ diagnostic value of ROC analysis. For DW-MRI derived parameters, the univariate analysis, standard deviation of D, Skewness and Kurtosis values of D* had a significant result to discriminate benign and malignant lesions and the best result at the univariate analysis in the discrimination of benign and malignant lesions was obtained by the Skewness of D* with an AUC of 82.9% (p-value = 0.02). Significant results for the mean value of Ktrans, mean value, standard deviation value and Skewness of kep, mean value, Skewness and Kurtosis of ve were obtained and the best AUC among DCE-MRI extracted parameters was reached by the mean value of kep and was equal to 80.0%. The best diagnostic performance in the discrimination of benign and malignant lesions was obtained at the multivariate analysis considering the DCE-MRI parameters alone with an AUC = 0.91 when the balancing technique was considered. Conclusions. Our results suggest that the combined use of DCE-MRI, DW-MRI and/or BOLD-MRI does not provide a dramatic improvement compared to the use of DCE-MRI features alone, in the classification of breast lesions. However, an interesting result was the negative correlation between R2* and D.

scholarly journals AB0501 CORRELATION BETWEEN AXIAL AND PERIPHERAL ENTHESIS IN SPONDYLARTHRITIS

2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 1278.1-1278
Author(s):  
H. Ferjani ◽  
M. Yasmine ◽  
K. Maatallah ◽  
E. Labbene ◽  
H. Riahi ◽  
...  
Keyword(s):  
Achilles Tendon ◽  
Chest Wall ◽  
Age Of Onset ◽  
Scoring Systems ◽  
Plantar Fascia ◽  
Anterior Chest Wall ◽  
Controlled Study ◽  
Asas Criteria ◽  
The Us ◽  
The Mean

Background:Enthesitis is the clinical hallmark of spondylarthritis. It refers to the inflammation of joint attach in the bone. Several sites enthesitis may be affected, and a wide variety of scoring systems were available.Objectives:We aimed to determine the prevalence of axial enthesitis in the anterior chest wall (ACW), and its correlation with peripheral sites especially, the Achilles tendon (AT).Methods:We conducted a prospective study including patients with SpA according to the ASAS criteria. Sociodemographic data, as well as disease characteristics, were recorded. The Maastricht Ankylosing Spondylitis Enthesitis Score (MASES) was used to assess clinical entheses (first and seventh costochondral joints, posterior superior iliac spine, anterior superior iliac spine, iliac crest, and Achilles tendon insertion). The presence of enthesitis on the US was then assessed in the right and left sternoclavicular (SCJ), manubriosternal (MSJ) joints, as well as in the AT, using Esaote My Lab 50.Results:The study included 47 patients with SpA: axial (n=26), axial and peripheral (n=21). There was a female predominance (sex ratio: 0.2). The mean age was 42.2 years ± 12.6 [11-70]. The age of onset of the disease was <40 years in 59.6% of cases. Tenderness in entheseal sites was found in 63.8% of patients, especially in the plantar fascia and AT (32.7%, 6%, respectively). The mean MASES score was 2.9 [0-13]. Clinical ACW involvement (29.1%) was at follows: 1st right chondro-sternal joint (CSJ) (19.1%), 1st left CSJ (25.5%), 7th right CSJ (27.7%) and 7th left CSJ (31.9%).US involvement of the ACW was 14.3%. Enthesitis of the AT was found in 70% of cases on US examination. ACW US involvement was correlated neither to the BMI nor to MASES score (p=0.16, p=0.6 respectively). Similarly, there was no correlation between the presence of US ACW enthesitis and clinical nor the US AT enthesitis (p=0.09, p=0.209, respectively).Conclusion:Our study showed that ACW enthesitis is frequent in SpA, especially by US screening. This axial enthesitis, don’t necessarily reflect a simultaneous clinical or US involvement of the peripheral entheses. Further studies are needed to characterize this subtype of SpA.References:[1]Verhoeven F, Guillot X, Godfrin-Valnet M, Prati C, Wendling D. Ultrasonographic evaluation of the anterior chest wall in spondyloarthritis: a prospective and controlled study. J Rheumatol. 2015;42(1):87-92Disclosure of Interests:None declared.

scholarly journals Direct costs of common osteoporotic fractures (Hip, Vertebral and Forearm) in Iran

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Marziyeh Rajabi ◽  
Afshin Ostovar ◽  
Ali Akbari Sari ◽  
Sayed Mahmoud Sajjadi-Jazi ◽  
Noushin Fahimfar ◽  
...  
Keyword(s):  
Direct Cost ◽  
Osteoporotic Fractures ◽  
Direct Costs ◽  
Fracture Incidence ◽  
Inpatient Cost ◽  
First Year ◽  
Forearm Fractures ◽  
Medical Sciences ◽  
The Us ◽  
The Mean

Abstract Background Osteoporotic fractures impose significant costs on society. The objective of this study was to estimate the direct costs of the hip, vertebral, and forearm fractures in the first year after fracture incidence in Iran. Methods We surveyed a sample of 300 patients aged over 50 years with osteoporotic fractures (hip, vertebral, and forearm) admitted to four hospitals affiliated to Tehran University of Medical Sciences, Iran, during 2017 and were alive six months after the fracture. Inpatient cost data were obtained from the hospital patient records. Using a questionnaire, the data regarding outpatient costs were collected through a phone interview with patients at least six months after the fracture incidence. Direct medical and non-medical costs were estimated from a societal perspective. All costs were converted to the US dollar using the average exchange rate in 2017 (1USD = IRR 34,214) Results The mean ± standard deviation (SD) age of the patient was 69.83 ± 11.25 years, and 68% were female. One hundred and seventeen (39%) patients had hip fractures, 56 (18.67%) patients had vertebral fractures, and 127 (42.33%) ones had forearm fractures. The mean direct cost (medical and non-medical) during the year after hip, vertebral and forearm fractures were estimated at USD5,381, USD2,981, and USD1,209, respectively. Conclusion The direct cost of osteoporotic fracture in Iran is high. Our findings might be useful for the economic evaluation of preventive and treatment interventions for osteoporotic fractures as well as estimating the economic burden of osteoporotic fractures in Iran.

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