scholarly journals Application of intraoral scanner to identify monozygotic twins

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Botond Simon ◽  
Laura Lipták ◽  
Klaudia Lipták ◽  
Ádám Domonkos Tárnoki ◽  
Dávid László Tárnoki ◽  
...  
Keyword(s):  
Twin Pair ◽  
Monozygotic Twins ◽  
High Specificity ◽  
Forensic Odontology ◽  
Tolerance Interval ◽  
Intraoral Scanner ◽  
Average Deviation ◽  
The Mean ◽  
Upper Tolerance Limit ◽  
Mz Twins

Abstract Background DNA base identification is a proper and high specificity method. However, identification could be challenged in a situation where there is no database or the DNA sequence is almost identical, as in the case of monozygotic (MZ) twins. The aim of this study was to introduce a novel forensic method for distinguishing between almost identical MZ twins by means of an intraoral scanner using the 3D digital pattern of the human palate. Methods The palatal area of 64 MZ twins and 33 same-sex dizygotic (DZ) twins (DZSS) and seven opposite-sex dizygotic twins (DZOS) were scanned three times with an intraoral scanner. From the scanned data, an STL file was created and exported into the GOM Inspect® inspection software. All scans within a twin pair were superimposed on each other. The average deviation between scans of the same subject (intra-subject deviation, ISD) and between scans of the two siblings within a twin pair (intra-twin deviation, ITD) was measured. One-sided tolerance interval covering 99% of the population with 99% confidence was calculated for the ISD (upper limit) and the ITD (lower limit). Results The mean ISD of the palatal scan was 35.3 μm ± 0.78 μm. The calculated upper tolerance limit was 95 μm. The mean ITD of MZ twins (406 μm ± 15 μm) was significantly (p < 0.001) higher than the ISD, and it was significantly lower than the ITD of DZSS twins (594 μm ± 53 μm, p < 0.01) and the ITD of DZOS twins (853 μm ± 202 μm, p < 0.05). Conclusion The reproducibility of palatal intraoral scans proved to be excellent. The morphology of the palate shows differences between members of MZ twins despite their almost identical DNA, indicating that this method could be useful in forensic odontology.

The Morphology of the Sella Turcica in Monozygotic Twins

2009 ◽  
Vol 12 (6) ◽  
pp. 598-604 ◽  
Author(s):  
Mette T. Brock-Jacobsen ◽  
Carsten Pallisgaard ◽  
Inger Kjær
Keyword(s):  
Statistical Evaluation ◽  
Twin Pair ◽  
Sella Turcica ◽  
Monozygotic Twins ◽  
Normal Karyotype ◽  
Mean Values ◽  
Reference Length ◽  
Standard Values ◽  
The Mean ◽  
Normal Standard

AbstractThe purpose was to compare the sella turcica morphology of individuals within pairs of monozygotic twins with normal karyotype and to analyze the similarity between the observed morphology and the morphology of non-twins at the same age with normal karyotype. Profile radiographs from 84 individuals of 42 twin pairs (18 male and 24 female pairs, aged 18–23 years) comprised the material. Sella turcica measurements from non-twins aged 6–21 years were used as normal reference. Length, depth and diameter of the sella turcica were measured and controlled by re-measurements. Pearson's correlation coefficient was used for comparison of individuals within twin pairs. For comparison of twins and non-twins, normal standard values for length, depth and diameter were subtracted from the twin values. For the mean values of these differences, confidence limitspvalues andtvalues were calculated. The study showed that the size of the sella turcica may be partly similar and partly dissimilar within the pair of monozygotic twins. Statistical evaluation of the data showed correlations between length, depth and diameter of the sella turcica between the two twin individuals in the same twin pair. Differences in sizes are observed between individuals in the twin material and individuals in the non-twin material. As a conclusion, the twin males were more similar within the twin pair, but deviated more from the non-twin material than the females. Female twins had more discrepancy within the twin pair, but deviated less from the non-twin material than the males.

scholarly journals Non-Invasive Molecular Survey of Sarcoptic Mange in Wildlife: Diagnostic Performance in Wolf Faecal Samples Evaluated by Multi-Event Capture–Recapture Models

Pathogens ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 243
Author(s):  
Julieta Rousseau ◽  
Mónia Nakamura ◽  
Helena Rio-Maior ◽  
Francisco Álvares ◽  
Rémi Choquet ◽  
...  
Keyword(s):  
Molecular Detection ◽  
High Specificity ◽  
Sarcoptes Scabiei ◽  
Sarcoptic Mange ◽  
Diagnostic Specificity ◽  
Non Invasive ◽  
Faecal Samples ◽  
Capture Recapture ◽  
The Mean ◽  
Event Capture

Sarcoptic mange is globally enzootic, and non-invasive methods with high diagnostic specificity for its surveillance in wildlife are lacking. We describe the molecular detection of Sarcoptes scabiei in non-invasively collected faecal samples, targeting the 16S rDNA gene. We applied this method to 843 Iberian wolf Canis lupus signatus faecal samples collected in north-western Portugal (2006–2018). We further integrated this with serological data (61 samples from wolf and 20 from red fox Vulpes vulpes, 1997–2019) in multi-event capture–recapture models. The mean predicted prevalence by the molecular analysis of wolf faecal samples from 2006–2018 was 7.2% (CI95 5.0–9.4%; range: 2.6–11.7%), highest in 2009. The mean predicted seroprevalence in wolves was 24.5% (CI95 18.5–30.6%; range: 13.0–55.0%), peaking in 2006–2009. Multi-event capture–recapture models estimated 100% diagnostic specificity and moderate diagnostic sensitivity (30.0%, CI95 14.0–53.0%) for the molecular method. Mange-infected individually identified wolves showed a tendency for higher mortality versus uninfected wolves (ΔMortality 0.150, CI95 −0.165–0.458). Long-term serology data highlights the endemicity of sarcoptic mange in wild canids but uncovers multi-year epidemics. This study developed and evaluated a novel method for surveying sarcoptic mange in wildlife populations by the molecular detection of S. scabiei in faecal samples, which stands out for its high specificity and non-invasive character.

Validity of hearTest Smartphone-Based Audiometry for Hearing Screening in Workers Exposed to Noise

2020 ◽  
Author(s):  
Luma Cordeiro Rodrigues ◽  
Silvia Ferrite ◽  
Ana Paula Corona
Keyword(s):  
Hearing Loss ◽  
High Specificity ◽  
Hearing Screening ◽  
Youden Index ◽  
Hearing Level ◽  
Predictive Values ◽  
Auditory Thresholds ◽  
The Mean ◽  
Low Sensitivity ◽  
Sensitivity Specificity

Abstract Purpose This article investigates the validity of a smartphone-based audiometry for hearing screening to identify hearing loss in workers exposed to noise. Research Design This is a validation study comparing hearing screening with the hearTest to conventional audiometry. The study population included all workers who attended the Brazilian Social Service of Industry to undergo periodic examinations. Sensitivity, specificity, the Youden index, and positive (PPV) and negative predictive values (NPV) for hearing screening obtained by the hearTest were estimated according to three definitions of hearing loss: any threshold greater than 25 dB hearing level (HL), the mean auditory thresholds for 0.5, 1, 2, and 4 kHz greater than 25 dB HL, and the mean thresholds for 3, 4, and 6 kHz greater than 25 dB HL. Note that 95% confidence intervals were calculated for all measurements. Results A total of 232 workers participated in the study. Hearing screening with the hearTest presented good sensitivity (93.8%), specificity (83.9%), and Youden index (77.7%) values, a NPV (97.2%), and a low PPV (69.0%) for the identification of hearing loss defined as any auditory threshold greater than 25 dB HL. For the other definitions of hearing loss, we observed high specificity, PPV and NPV, as well as low sensitivity and Youden index. Conclusion The hearTest is an accurate hearing screening tool to identify hearing loss in workers exposed to noise, including those with noise-induced hearing loss, although it does not replace conventional audiometry.

scholarly journals Oliver Sacks: Our Correspondence About Twins/Twin Research: Vanishing Twins Syndrome; Discordant Sex in MZ Twins; Pregnancy Outcomes in IVF and ICSI Conceived Twins/Print and Media: Superfetated Twins; Twins Discordant for Smoking; Twins in Fashion; Yale University Twin Hockey Players; Conjoined Twin–Visiting Professor

2017 ◽  
Vol 20 (4) ◽  
pp. 363-369
Author(s):  
Nancy L. Segal
Keyword(s):  
New York ◽  
Pregnancy Outcomes ◽  
Twin Pair ◽  
Multiple Pregnancy ◽  
New York Times ◽  
Yale University ◽  
Twin Research ◽  
Hockey Players ◽  
Vanishing Twin Syndrome ◽  
Mz Twins

The late neurologist and author, Oliver Sacks, published an insightful 1986 review of Marjorie Wallace's book, The Silent Twins, in the New York Times. Taking exception to his assertion about Sir Francis Galton, I wrote a letter to the Times’ editor. The letter was unpublished, but it brought a wonderful response from Sacks himself that is reproduced and examined. Next, brief reviews of twin research concerning the vanishing twin syndrome (VTS), discordant sex in a monozygotic (MZ) twin pair, and multiple pregnancy outcomes from assisted reproductive technology (ART) are presented. This section is followed by popular coverage of superfetated twins, smoking-discordant co-twins, twins in fashion, Yale University twin hockey players, and a visiting professor who was a conjoined twin.

Validity of the Zygosity Questionnaire and Characteristics of Zygosity-Misdiagnosed Twin Pairs in the Healthy Twin Study of Korea

2010 ◽  
Vol 13 (3) ◽  
pp. 223-230 ◽  
Author(s):  
Yun-Mi Song ◽  
Dong-Hun Lee ◽  
Mi Kyoung Lee ◽  
Kayoung Lee ◽  
Hee Jung Lee ◽  
...  
Keyword(s):  
Twin Study ◽  
Twin Pair ◽  
Correct Diagnosis ◽  
Striking Similarity ◽  
Genotype Information ◽  
Zygosity Questionnaire ◽  
Questionnaire Method ◽  
Short Tandem Repeat Markers ◽  
Mz Twins ◽  
Short Tandem

AbstractDetermining valid zygosity is a basic and important requirement in a twin study, because misdiagnosing zygosity leads to biased results. The Healthy Twin Study has collected data from adult like-sex twins and their families since 2005. In the study, a questionnaire to determine zygosity was developed comprising four questions; one concerning the degree of resemblance, and three concerning the degree of confusion by the resemblance. Among 2,761 individuals (624 twin pairs) of twin and their families, 406 pairs of twins (mean age 38.3, 63.5% women) with both questionnaire and genotype information were selected to examine the validity of the zygosity questionnaire using 16 short tandem repeat markers. We first determined individual zygosity including undetermined category, and then decided the zygosity of a twin pair using a decision tree. Sensitivity of questionnaire diagnosis was 98.8% for monozygotic (MZ) and 88.9% for dizygotic (DZ) twins, and positive predictive value was 97.2% for MZ and 95.0% for DZ. When we compared correctly and wrongly diagnosed twin pairs, misdiagnosed DZ twins (nine pairs) showed striking similarity in stature or obesity even exceeding that of true MZ twins. Our finding suggests that a parsimonious questionnaire method of diagnosing the zygosity will be useful, and adding physical or physiological measurements to a questionnaire of zygosity diagnosis will either confound the correct diagnosis or reduce the efficiency of the study compared with using questionnaire alone or with introducing genotyping.

scholarly journals Modelling Geometric Measure of Variation About the Population Mean

2021 ◽  
Author(s):  
Benedict Troon
Keyword(s):  
Mean Deviation ◽  
Average Deviation ◽  
Statistical Tool ◽  
Population Mean ◽  
Geometric Measure ◽  
Initial Dataset ◽  
Algebraic Laws ◽  
Average Variation ◽  
Measures Of Dispersion ◽  
The Mean

Measures of dispersion are important statistical tool used to illustrate the distribution of datasets. These measureshave allowed researchers to define the distribution of various datasets especially the measures of dispersion from the mean.Researchers and mathematicians have been able to develop measures of dispersion from the mean such as mean deviation, variance and standard deviation. However, these measures have been determined not to be perfect, for example, variance give average of squared deviation which differ in unit of measurement as the initial dataset, mean deviation gives bigger average deviation than the actual average deviation because it violates the algebraic laws governing absolute numbers, while standarddeviation is affected by outliers and skewed datasets. As a result, there was a need to develop a more efficient measure of variation from the mean that would overcome these weaknesses. The aim of this paper was to model a geometric measure of variation about the population mean which could overcome the weaknesses of the existing measures of variation about the population mean. The study was able to formulate the geometric measure of variation about the population mean that obeyedthe algebraic laws behind absolute numbers, which was capable of further algebraic manipulations as it could be used further to estimate the average variation about the mean for weighted datasets, probability mass functions and probability density functions. Lastly, the measure was not affected by outliers and skewed datasets. This shows that the formulated measure was capable of solving the weaknesses of the existing measures of variation about the mean

scholarly journals Twin Birth Order, Birthweight and Birthweight Discordance: Any Relationship?

1970 ◽  
Vol 6 (1) ◽  
pp. 46-50
Author(s):  
Alphonsus N Onyiriuka
Keyword(s):  
Birth Weight ◽  
Confidence Interval ◽  
Birth Order ◽  
Twin Pair ◽  
Twin Birth ◽  
Common Concept ◽  
The Mean ◽  
Male Twin ◽  
Discordant Twin

Aim: To assess the truthfulness of this common concept that first-born twins are usually heavier than their second-born siblings at birth. Methods: In a series of 104 sets of live-born twins, the birth weights of first-born twins were compared with those of their second-born siblings, after controlling for gender. Their intra-pair birthweight differences were determined and twin pairs whose birthweight difference was 15% or more were designated as discordant. Results: Twin I was heavier than Twin II in 61.5% of cases while Twin II was heavier than Twin I in 28.9% of cases. Twins I and II had equal birth weight in 9.6% of cases. Comparing the mean birthweight of the first-born-male twin with that of second-born- male twin, it was 2515 + 427g [95 % Confidence Interval, CI = 2402 - 2628) versus 2432 + 435g (95% C I = 2321 - 2543) p>0.05. The mean birthweight of first-born-female twin was 2326 + 445g (95% CI =2214 - 2439) while that of the second-born-female twin was 2325 + 501g (95% CI = 2197 - 2453) p>0.05. When the birthweight difference exceeded 750g, the probability that Twin I will be heavier than Twin II was 83.3% (5 of 6). Conclusion: Although the first-born twin was more often heavier than their second-born siblings, either could weigh more or less at birth. The larger the birthweight difference between growth-discordant twin pair, the greater the probability that the heavier twin would be delivered first. Keywords: Birth order relative birth weights, birthweight discordance, twins DOI: http://dx.doi.org/10.3126/njog.v6i1.5252 NJOG 2011; 6(1): 46-50

scholarly journals In vitro Comparison of Accuracy of Two Scanners Used in Dental Medicine

2019 ◽  
Vol 70 (7) ◽  
pp. 2344-2346
Author(s):  
Alexandru Victor Burde ◽  
Marius Manole ◽  
Radu-Septimiu Campian ◽  
Cosmin Sinescu ◽  
Sorana Baciu
Keyword(s):  
Experimental Model ◽  
Reference Model ◽  
Direct Consequence ◽  
Intraoral Scanner ◽  
Average Deviation ◽  
Virtual Reference ◽  
Significant Difference ◽  
Industrial Ct ◽  
In Vitro Comparison

This experimental study aims to highlight and compare the resolution and accuracy (trueness and fidelity) of an intraoral scanner and a laboratory scanner. In order to achieve the aim of this study, an experimental model consisting of a die with a standard preparation for a porcelain-fused to metal crown was manufactured from a physiognomic polymethylmethacrylate resin. The experimental model was scanned with an industrial CT to obtain the virtual reference model. Then, the die was scanned 15 times with each scanner. In order to asses trueness, comparisons were made with the virtual reference model, and for fidelity, the first scan in the series was compared with the following scans. In regards to the trueness of the scanners, the average deviation for the laboratory scanner is 4.31 and 17.34 mm for the intraoral scanner. When comparing the serial scannings� of the same die, the lowest recorded deviation is 6.4 mm for the laboratory scanner and 21.57mm for the intraoral scanner. For both fidelity and trueness, the F test demonstrates that there is a statistically significant difference between the scanners and the applied T-tests confirm the lower degree of error-rate generation by the laboratory scanner. The dimensional limitations imposed for the intraoral scanners have a direct consequence on their trueness and fidelity when compared to their laboratory counterparts.

On the Statistical Significance of one Pair of Monozygotic Twins in Clinical Genetics

1963 ◽  
Vol 12 (4) ◽  
pp. 317-323
Author(s):  
L. Gedda
Keyword(s):  
Twin Pair ◽  
Statistical Significance ◽  
Statistical Treatment ◽  
Monozygotic Twins ◽  
Monozygotic Twin ◽  
Clinical Genetics ◽  
Pair Comparison ◽  
Monozygotic Twin Pair ◽  
Development Result

SUMMARYA case of one twin pair concordant or discordant as to a given disease is always very important for Clinical Genetics, especially when it is monozygotic. In Clinical Genetics, isolated pairs occur to the physician, and the diagnosis must therefore be based on intra-pair comparison. The statistical treatment of the case must consider the fact that a concordant monozygotic twin pair represents a statistical universe rather than a statistical unit. This entails taking into account many traits concerning the time of onset, the symptoms, development, result of treatment, etc. Suggestions are made for the statistical treatment of such cases.

Sign in / Sign up

Export Citation Format

Share Document