Regression Formula Research Articles

Estimating Morphological Nose Features for Craniofacial Reconstruction: A Retrospective Study

Abstract Background: Craniofacial reconstruction is one of the techniques used in forensic sciences to rebuild the probable antemortem face of unknown human skulls. Considering the soft-tissue thickness, the skull is covered with clay or similar material. After covering, facial features such as lips, ears, eyes, and nose should be added. The nose has considerable diversity. This variety makes it have substantial importance for facial recognition. Aims and Objectives: The current study aimed to determine the morphology of the nose of the Anatolian population and develop regression formulas to estimate the nose shape using the measurements of the skull. Materials and Methods: The current study was conducted on three-dimensional computed tomography cranial images. The images belonging to 50 adult patients (25 males, 25 females) were taken from the Radiology Department of Bursa Uludag University Medical Faculty Hospital. Eighteen parameters on bony structure and twenty-four parameters on soft tissue were measured using ImageJ software. SPSS 22.0 was performed for statistical analyses. Results: The regression formulas were developed to estimate the nose morphology belonging to the skull using the correlated parameters between the bony structure of the skull and soft tissue. Conclusion: Accurate nasal shape prediction means increasing the identification of the unknown skull. We believe that the regression formulas, developed with this idea could be helpful in craniofacial reconstruction.

Comparison of magnification corrected optic disc size by slit-lamp biomicroscopy, fundus photography, and optical coherence tomography

Abstract PURPOSE: Optic disc size measurement is essential for determining landmarks, lesions, and distances of the retina. Due to the size variability in nature and when measured with different instruments, newer methods to compare sizes between different instruments are needed. We aimed to determine the comparability of slit lamp, fundus photography, and optical coherence tomography (OCT) measurements of optic disc size after correcting for both ocular and instrument magnification. MATERIALS AND METHODS: In this prospective, observational study, optic disc size was measured by slit-lamp biomicroscopy, fundus photography, and OCT. Instrument and ocular magnification was calculated, and the measured size was corrected for both using the Littman formula. The corrected values were analyzed using Bland–Altman plots and intra-class correlation (ICC) for agreeability and correlation, respectively. Linear regression analysis was conducted to estimate the systematic errors and interconvertibility in cases of high correlation. RESULTS: Fifty-six eyes were included for the analysis. Uncorrected and corrected values for each method had excellent correlation and agreeability (ICC absolute agreement >0.75, P < 0.01). Among magnification corrected values, slit lamp and OCT had excellent correlation and agreement (ICC consistency = 0.846, confidence interval 0.75–0.91, P < 0.01). This pair had R 2 = 0.73 on linear regression (P < 0.01). Linear regression formulas for interconverting uncorrected and corrected values for the three methods had variable accuracy (R 2 from 0.47 to 0.66). CONCLUSION: Uncorrected values of different methods for disc size measurement cannot be compared directly; they need ocular and instrument magnification correction. Among the three methods compared, the best interconvertible pairs of measurement were magnification corrected slit lamp and OCT values.

Computed tomography study of cranial vault thickness in Malaysian subadult population.

Cranial vault thickness (CVT) and its variations provide valuable insights into an individual's biological attributes such as age and sex. This paper aimed to assess the correlations of CVT with age and sex and develop a regression model for age estimation in Malaysian subadults using computed tomography (CT) images. A total of 521 CT images (male/female: 279/242; age range: 0-20 years; Malay/Chinese/Indian: 221/145/155) were included in the study. Correlations of CVT measurements with age and sex, including frontal bone thickness (FBT), occipital bone thickness (OBT), left parietal bone thickness (LPBT), and right parietal bone thickness (RPBT) were assessed and regression formulae were developed for age estimation in subadults. A significant correlation between CVT measurements and age was demonstrated (p < 0.001). Age estimation was most accurate in the younger age group (< 2 years) at frontal and occipital, and accuracy decreases in the older age groups. Additionally, sexual dimorphism was evident in the frontal and parietal bone thickness within the age range of 3-6 years and 16-20 years, respectively. In conclusion, the findings suggested CVT measurements could be used to corroborate other age estimation methods for subadults.

Anthropometric and Demographic Features Affect the Interpretation of Cerebrospinal Fluid Biomarkers in Patients with Different Dementia Syndromes and Cognitively Healthy Adults.

Clinical distinction between dementia with Lewy bodies (DLB) and late-onset Alzheimer's disease (AD) is difficult, while several features might affect the analyses of biomarkers. This study aimed to verify associations of anthropometric and demographic features with cerebrospinal fluid biomarkers, their ratios, and restructured traditional regression formulas in patients with DLB and AD, as well as in cognitively healthy controls. Consecutive outpatients with DLB were paired with outpatients with AD according to sex, dementia stage, and cognitive status, and with controls according to sex and age to investigate associations of sex, age, dementia duration, total sleep time, body mass index, alcohol use, smoking, sanitation, and APOE-ε4 alleles on the measurement of cerebrospinal fluid α-synuclein, biomarker ratios, and restructured traditional regression formulas involving amyloid-β (Aβ42,Aβ40,Aβ38), tau, and phospho-tau Thr181. Overall, 81 participants were included with DLB (n = 27;11 APOE-ε4 +) or AD (n = 27;12 APOE-ε4 +), and controls (n = 27;4 APOE-ε4 +); two thirds were women. Cerebrospinal fluid evidence of amyloidosis and tauopathy was more prevalent among women with AD, while Aβ42/Aβ38 could also discriminate men with DLB from men with AD. Restructured traditional regression formulas had higher diagnostic accuracy for women with AD. Aging, higher body mass index, and APOE-ε4 alleles were associated with amyloidosis in DLB, while only in AD were higher body mass index associated with lower tau pathology load, and more alcohol use associated with higher phospho-tau Thr181/Aβ42. These findings confirm the effects of anthropometric and demographic features on cerebrospinal fluid biomarkers, and also differences in aberrant amyloidosis and tauopathy between DLB and AD.

An investigation of the relationship between long bone measurements and stature: Implications for estimating skeletal stature in subadults.

The present study introduces new regression formulae that address several challenges of current subadult stature estimation methods by 1) using a large, contemporary, cross-sectional sample of subadult skeletal remains; 2) generating regression models using both lengths and breadths; 3) utilizing both linear and nonlinear regression models to accommodate the nonlinear shape of long bone growth; and 4) providing usable prediction intervals for estimating stature. Eighteen long bone measurements, stature, and age were collected from computed tomography images for a sample of individuals (n = 990) between birth and 20 years from the United States. The bivariate relationship between long bone measurements and stature was modeled using linear and nonlinear methods on an 80% training sample and evaluated on a 20% testing sample. Equations were generated using pooled-sex samples. Goodness of fit was evaluated using Kolmogorov-Smirnov tests and mean absolute deviation (MAD). Accuracy and precision were quantified using percent testing accuracy and Bland-Altman plots. In total, 38 stature estimation equations were created and evaluated, all achieving testing accuracies greater than 90%. Nonlinear models generated better fits compared to linear counterparts and generally produced smaller MAD (3.65 - 15.90cm). Length models generally performed better than breadth models, and a mixture of linear and nonlinear methods resulted in highest testing accuracies. Model performance was not biased by sex, age, or measurement type. A freely available, online graphical user interface is provided for immediate use of the models by practitioners in forensic anthropology and will be expanded to include bioarchaeological contexts in the future.

Oxygen-Carbon and Strontium Isotope Composition in Primary Carbonatites of the World: The Data Summary and Linear Trends

A statistical regression analysis was performed of a summary of borrowed literary isotopic data on 176 carbonatite occurrences worldwide (a total of 1829 paired δ18О-δ13С values in primary carbonatites). For most of the occurrences, distinct linear trends in δ18О-δ13С values were revealed, approximated in diagrams by vectors using the regression formula y = kx + b. Trends in three directions are distinguished. The dominating trend possesses the angular coefficient k in the range of 0.0÷+0.6, averaging at + 0.31 (direct correlation δ18О-δ13С). In the literature, it is associated with the Rayleigh high-temperature fractionation of carbonatite melts or with their sedimentary crustal contamination. The second trend with k from 0.0 to -0.7 (inverse correlation δ18О-δ13С) is associated with CO2 degassing from the melts. The third trend with k from +0.6 to +1.5 is rare. In other carbonatite occurrences, no linear trends in δ18О-δ13С values are detected. This may be a consequence of a combined action of the multidirectional linear trends. In this regard, the initial point of the trend vectors is accepted as a universal isotope indicator for all the carbonatite occurrences. In the δ18О-δ13С diagram, the box PC-90 is outlined in the field of the initial points, including 90 % of the primary carbonatite occurrences. The coordinates of the corner points of the box in δ18О-δ13С ‰ are (+5÷-8), (+5÷-5), (+5.5÷-2.5), (+12÷-2.5), (+12÷-7), (+9÷-8.5). The box PC-90 is subdivided into two parts by the carbon isotope composition, using the value δ13C = -5.2 ‰. This suggests that the deep sources differ in carbon isotope composition. No correlation is found in the oxygen-carbon and strontium isotope compositions in the carbonatites, which suggests that the deep sources are also heterogeneous in the strontium isotope composition.

Stepped chute energy dissipation structure downstream of a low-level river crossing for embankment protection

A low-level river crossing is an economic means of providing access for lower-order roads during high-frequency flood events. Conventionally, culverts are employed to enable the flow to traverse the road, albeit with allowance for overtopping. This overtopping flow from the approach roads, however, possesses the potential to cause erosion of the downstream embankment, thereby jeopardising the foundational integrity of the structure. A physical modelling study was undertaken to investigate the hydraulic performance of stepped chutes in terms of flow patterns, air-water flow properties, and energy dissipation. Various types of stepped chutes were investigated, namely horizontal steps with a chute wall, horizontal steps without a chute wall but with riprap placed directly downstream of each chute, step-inclined steps (backward sloping), steps with pooled cascades, and steps with baffle blocks. Notably, chutes with horizontal steps were the most efficient configuration in terms of relative energy dissipation. Furthermore, this research culminated in the formulation of a new regression formula to establish a quantifiable relationship between the required step length and the overflow depth and discharge, thereby offering a valuable tool for design purposes.

Improvement of Sonic Logging Porosity Calculation Method in South Sulige Block

Abstract South Sulige Block is a lithologic gas reservoir with low porosity and permeability, low pressure and low abundance, of which the heterogeneity is very high and pore structure is complex. Due to the influence of lithology and pore structure, the skeleton value is uncertain and it is hard to give a fixed value. It is difficult to obtain the true porosity of formation accurately by using the traditional method of calculating porosity by Wyllie formula in sonic logging. In this paper, according to the principle of sonic logging and rock response characteristics, combined with core analysis data of this area and adjacent areas, using the acoustic time and core analysis porosity regression formula to calculate porosity first, and then, according to different shale content, the corresponding shale correction is carried out for heavy shale content intervals on the basis of core regression formula, which eliminates the porosity calculation error caused by the influence of shale content. Practical application shows that the porosity calculated by this method is in good agreement with the results of core analysis, and can reflect the reservoir characteristics and production capacity of the formation more truly.

Determination of body length regression formulas for the golden grey mullet (Chelon auratus, Risso 1810) based on otoliths found in the feces of the Caspian Seal (Pusa caspica Gmelin, 1788)

The Caspian Seal, the sole mammal endemic to the Caspian Sea, is listed in the IUCN Red List as a species facing the threat of extinction, a status similarly recognized and/or assigned in all countries in the Caspian region.The study of seal nutrition using caprological methods is of great interest for understanding animal adaptation to deteriorating habitat conditions and assessing the adequacy of their food base in the sea. This method involves analyzing the contents of feces from ichthyophages to detect undigested fish otoliths.The results of studying the seal's diet during periods of haulout on breeding grounds showed that the frequency of occurrence of Chelon auratus otoliths ranged from 2-3% to 27.7% of all fish otoliths detected in feces.This study aims to assess changes in Chelon auratus otoliths as they pass through seals' gastrointestinal tracts and estimate formulas for recovering the linear dimensions of fish consumed by these seals.The research indicates that otolith growth slows with fish growth but does not cease entirely. Allometry is evident in the different ratios of otolith length and width to fish length in various size groups and the change in otolith shape as fish grow.To recover the body length of fish consumed by seals based on otoliths found in their feces, applying inverse calculation formulas obtained when studying the relationship between otolith growth and fish body growth using collection material obtained directly from fish is possible.Further research should focus on refining the recovery formula for the length of large fish by dividing the length into several segments, each described by separate formulas describing the relationship between fish body length and otolith length and width growth.

ANALISIS KADAR ALKALOID DAN FLAVONOID SEDUHAN RAMBUT JAGUNG (Zea mays L. ) DENGAN METODE SPEKTROFOTOMETRI UV-VIS

Corn silk is generally a waste of sweet corn plants after being harvested and is rarely used, however, on the other hand, corn silk is also used by the community as herbal medicine and is believed to reduce the risk of hypertension and other types of chronic diseases such as kidney infections. Corn silk is thought to contain metabolite compounds such as flavonoids, essential oils, steroids, and alkaloids. Alkaloid compounds can function as drugs and strong activators for immune cells that can destroy bacteria, viruses, fungi, and cancer cells. Flavonoid compounds are compounds that have various bioactive effects such as anti-inflammatory, antiviral, cardioprotective, anti-diabetic, anti-cancer, anti-aging, and antioxidants. it is necessary to measure the levels of alkaloids and flavonoids from corn silk infusion to determine the levels of alkaloid and flavonoid compounds in corn silk infusion. The method used in this study is the Uv-Vis spectrophotometry method. The alkaloid content was calculated using the regression formula y = 0.0895x - 0.3046, the results obtained in the corn hair infusion extract were 46.36 mg / g extract, and the flavonoid content was calculated using the regression formula y = 0.0144 x - 0.025 and the results obtained in the corn hair infusion extract were 85.42 mg / g extract. So it can be concluded that corn hair infusion contains more flavonoid compounds, namely with alkaloid compound levels of 46.36 mg / g extract and flavonoid compounds of 85.42 mg / g extract.

The Impact of New Quality Productive Forces on Carbon Emissions in Manufacturing Enterprises

The article innovatively explores new quality productive forces, focusing on their core role in driving carbon emissions. It investigates new quality productive forces' mechanisms and development pathways within the new economic environment. The paper delves deeper into the intrinsic connections between new quality productive forces and carbon emissions than existing research. Firstly, the paper investigates the impact and transmission mechanisms of China's new quality productive forces on green development. It calculates the carbon emissions of 2,364 manufacturing companies listed on the Shanghai and Shenzhen stock exchanges from 2011 to 2021. The study's empirical findings indicate that new quality productive forces promote carbon emissions reduction for publicly listed companies in the manufacturing sector. Lastly, the regression formula includes the number of patents listed companies hold. It is to consider the relationship between new quality productive forces and carbon emissions.

Pengaruh Usaha Budidaya Bebek Petelur Terhadap Perekonomian Keluarga di Desa Sukamerindu Kecamatan Pemulutan Barat

This research aims to find out the influence of petal duck business on the family economy in Sukamerindu Village, Indralaya district of Ogan Ilir. The approach used in this research is quantitative with the type of descriptive research. The population of this research is an entrepreneurial duck with a sample of 30 entrepreneurs using a census sample technique. Data collection techniques using observation and lifting. Data analysis techniques using simple linear regression formulas. The results of the research showed that there was an influence between the business of the duck on the family's economy. For influence business ducks belong to the low category. With the result of a ritung value &gt; rtable that is a positive influence on the economy of the family that has a contribution of 0.153 or. That means every 1% increase in the rate of breeding of the duck (X), then the increase in income (Y) will increase by 0.153. As far as the positive impact of the breeding of the duck is concerned, it can be seen from the result that the majority of the community that has an undertaking of breeding ducks is able to meet the daily needs of quality food, have sufficient water, and are able to satisfy daily needs. It can be concluded that the results of the research there is a positive relationship between the cultivation of ducks petal against the economy of the family in the village of Sukamerindu district of Ogan Ilir.

Multireference calculations on bond dissociation and biradical polycyclic aromatic hydrocarbons as guidance for fractional occupation number weighted density analysis in DFT calculations

This study explores open-shell biradical and polyradical molecular compounds based on extended multireference (MR) methods (MR-configuration interaction with singles and doubles (CISD) and MR-averaged quadratic coupled cluster (AQCC) approach) using the numbers of unpaired densities NU. These results were used to guide the analysis of the fractional occupation number weighted density (FOD) calculated within the finite temperature (FT) density functional theory (DFT) approach. As critical test examples, the dissociation of carbon–carbon (CC) single, double and triple bonds and a benchmark set of polycyclic aromatic hydrocarbons (PAHs) have been chosen. By examining single, double, and triple bond dissociations, we demonstrate the utility and accuracy but also limitations of the FOD analysis for describing these dissociation processes. In significant extension of previous work (Phys Chem Chem Phys 25: 27380–27393), the assessment of FOD applications for different classes of DFT functionals was performed examining the range-separated functionals ωB97XD, ωB97M-V, CAM-B3LYP, LC-ωPBE, and MN12-SX, the hybrid (M06-2X) functional and the double hybrid (B2P-LYP) functional. In all cases, strong correlations between NFOD and NU values are found. The major task was to develop a new linear regression formula for range-separated functionals allowing a convenient determination of the optimal electronic temperature Tel for the FT-DFT calculation. We also established an optimal temperature for the semiempirical extended tight-binding GFN2-xTB method. These findings significantly broaden the applicability of FOD analysis across various DFT functionals and semiempirical methods.

Inequalities in severe COVID-19 outcomes in Wales, UK

ObjectiveResearch evidence shows that COVID-19 has disproportionately affected people from more deprived backgrounds. In Wales (UK), there is strong evidence of a socioeconomic gradient in total hospitalisations, critical care admissions and deaths. This study focussed on a cohort of the Welsh population using anonymised individual-level linked population-scale data in the SAIL Databank. ApproachThis analysis examines the impact of confounding/mediating factors on severe health outcomes. We used logistic regression, considering the Welsh Index of Multiple Deprivation (WIMD) 2019 as a predictor, to investigate how the coefficient for WIMD is changed when other variables (such as comorbidities, smoking status, Body Mass Index) are added, aiming to understand whether inequalities are mediated by observed characteristics or related to other unobserved factors. ResultsInitial findings show that age-standardised rates of hospital admissions, Intensive Care Unit (ICU) admissions and deaths were roughly twice as high in the most deprived vs least deprived WIMD quintile in Wales. We estimated Years of Life Lost per 1,000 due to COVID-19 as 28.9, with variation between WIMD quintiles of 38.4 for the most deprived and 22.2 for the least deprived. The project also produced regression formulas to evaluate the contribution of the different confounding factors. ConclusionThis study built on existing research findings and further explored the potential reasons for known socioeconomic inequalities in relation to COVID-19 outcomes. Insights from this study have broadened the knowledge around the impact of mediating factors and may contribute to future pandemic preparedness and the formation of future policies.

Estimating high-resolution soil moisture by combining data from a sparse network of soil moisture sensors and remotely sensed MODIS LST information

ABSTRACT The present work demonstrates a methodology for acquiring high-resolution soil moisture information, namely at 1 km at a daily time step, utilizing data from a sparse network of soil moisture sensors and remotely sensed Land Surface Temperature (LST). Building on previous research and highlighting the strong correlation between surface soil moisture and LST, as a result of the thermal inertia, we first evaluated the correlation between Moderate Resolution Imaging Spectroradiometer (MODIS) LST and ground-based soil moisture information from soil moisture sensors installed in a pilot area in Northeastern Greece. Second, a regression formula was developed for three out of six soil moisture sensors, keeping the three remaining monitoring stations serving as a validation set. Furthermore, regression coefficients were interpolated at 1 km and the regression equations were applied for the entire study area, thus acquiring soil moisture information at a spatial resolution of 1 km at the daily time step. The verification process indicated a reasonable accuracy, with a mean absolute error (MAE) of &amp;lt;0.02 m3/m3. The results were considerably better than using a simple interpolation or downscaled daily 1-km SMAP soil moisture.

Pengaruh Motivasi Kerja Terhadap Kinerja Karyawan pada Staff Office PT Summit Adyawinsa Indonesia

This Research is a quantitative research using questionnaires as a data collection tool distributed to respondents with a sample of 60 people. In analyzing the data, simple linear regression analysis and hypothesis testing were used. This study aims to determine how much influence work motivation has on employee performance in the office staff of PT Summit Adyawinsa Indonesia. Based on the results of the analysis carried out using SPSS 25.0, the value of Work Motivation (X) on Employee Performance (Y) can be explained by the regression formula Y= a+bX, then the regression value resulting from the calculayion above is Y= 20,726+0,616X. Based on the results of the t test, namely t count (5,803) is smaller than the t table value (2,000). Then work motivation has a high positive influence with an r value of (0,606) and has a contribution of 36,7% on Employee Performance of PT Summit Adyawinsa Indonesia (SAI). While the rest is influenced by other factors that were not included in the research.

Determination of Propeller-Rudder-Hull Interaction Coefficients in Ship Manoeuvring Prediction

Abstract The assessment of ship manoeuvring properties is a crucial part of the process of ship design and is usually first carried out during the model test phase of the project. According to the International Maritime Organisation (IMO), the manoeuvrability of the ship can be assessed on the basis of the standard trial manoeuvres. In order to do this, free running model tests or captive model tests are used, in conjunction with a mathematical model of ship motion; this is considered to be a reliable prediction method. In recent years, numerical-based methods have also been widely used in ship hydrodynamics and constantly improving computing power and more accurate fluid dynamics models have made the simulation of more complex cases possible. The study presented in this paper focuses on the determination of propeller-rudder-hull interaction coefficients based on the Mathematical Modelling Group (MMG) standard method in ship manoeuvring prediction. The identification of the parameters uses both captive model tests and a simplified numerical method, as well as regression formulas. The results of 35° turning and 10°/10° zig-zag manoeuvres, obtained with the use of each prediction method, are then compared. The test case used in the study is the container type cargo ship equipped with a single propeller and rudder. The model scale, for which the referenced model tests were carried out, is equal to 1:25 and a NACA 0020 rudder profile was used. This research highlights the advantages and disadvantages of each presented prediction method and their potential for future improvement.

Virtual skeleton and body mass for revealing the life strategies of Sinosaurus

ABSTRACT Sinosaurus from the Lufeng Basin, Yunnan Province, is the largest and most famous predatory dinosaur from the Early Jurassic in China. Although a number of specimens have been discovered in the past, no studies to date have focused exclusively on complete skeletal articulation, estimation of mass, or life strategies. Based on surface scans of a new well-preserved specimen, a digital skeleton of Sinosaurus was produced in two poses: osteologically neutral pose and extended pose. We estimated the possible living body mass by three volumetric-density methods, advocating the use of the expanding convex hulls method of 849.6 kg with the COM (0.41, 1.31, 0.00) as a more reliable result, which is greater than the mass of traditional regression formulas. The body shape and skull/body length suggested that Sinosaurus was a great runner, and this, combined with the weak crests and large forelimbs, further led to the conclusion that both the head and forelimbs were required to prey. This finding is also consistent with the finding that Sinosaurus has a moderate ability to metabolise body heat in the skin, as reflected by the surface/volume ratio.

ELOVL2, PRKG2, and EDARADD DNA Methylation Strongly Estimate Indonesian Adolescents.

Recently, there has been a growing interest in using DNA methylation analysis for age estimation. Despite this growing interest, there is a scarcity of research on the potential of DNA methylation as a biomarker for age estimation in Indonesia. This study aims to investigate the applicability of ELOVL2, PRKG2, and EDARADD genes for forensic identification in the 11-20 age group among Indonesians. This research utilizes 43 archived blood samples from healthy individuals who underwent blood tests at the Gatot Soebroto Army Hospital (RSPAD) in Central Jakarta, Indonesia. The methylation-specific PCR (MSP) technique assessed the DNA methylation level. The key findings of this study include (1) a strong positive correlation between methylation levels in the ELOVL2 gene and age; (2) a strong negative correlation between methylation levels in PRKG2 and EDARADD genes with age; (3) the development of three linear regression formulas for age prediction; and (4) mean absolute error (MAE) values derived from this research, which are ±0.48 for ELOVL2 gene regression formula, ±0.58 for PRKG2 gene regression formula, and ±0.72 for EDARADD gene regression formula. In summary, this study explores the potential of DNA methylation analysis for age estimation in Indonesia, focusing on ELOVL2, PRKG2, and EDARADD genes in the 11-20 age group. The findings underscore the applicability of DNA methylation analysis in forensic identification and age estimation, paving the way for future research in this field.

Estimation of pupil size at iris plane and its magnification after cataract surgery.

To estimate the pupil size (at the iris plane) under photopic (PPH) and scotopic (PS) conditions after phacoemulsification with intraocular lens (IOL) implantation. This retrospective observational cohort study included 190 virgin eyes from 190 patients who underwent cataract surgery with IOL implantation. Data collected with Aladdin (Topcon), AS-OCT MS-39 (CSO), and iTrace (Tracey) were SimK, mean pupillary power at 6 mm (MPP), anterior chamber depth (ACD), lens thickness (LT), axial length (AL), lens rise (LR), PPH and PS before and after surgery at 30 days, dysfunctional lens index, and opacity grade. The position of the postoperative iris plane (PIP) was measured manually with MS-39, and a multivariate regression formula was developed to predict it. Statistical analysis was performed using Statistical Package for Social Science (SPSS) (IBM). The mean and standard deviations were 42.61 ± 3.20 D for MMP at 6 mm, 3.35 ± 0.37 mm for ACD, 3.89 ± 0.18 mm for PIP (P < 0.01), 4.55 ± 0.42 mm for LT, 0.43 ± 0.24 mm for LR, and 25.91 ± 3.03 mm for AL. The mean preoperative and postoperative topographic pupil magnification was 12% and 14.22%, respectively (P < 0.01). Despite an increase in magnification, the postoperative pupil was smaller than the preoperative one both for scotopic and photopic conditions: The larger the preoperative pupil, the more it tends to reduce in the postoperative period. Analysis of the preoperative topographic pupil alone is not sufficient for a correct indication of the optical zone and total diameter of IOL to be implanted but must be correlated with biometric data. The topographic pupil, therefore, undergoes a change in magnification from the preoperative period to the postoperative period. Furthermore, the real pupil presents a modification and, in most cases, tends to be smaller postoperatively in both photopic and scotopic conditions.