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For topical, dermatological drug products, an in vitro option to determine bioequivalence (BE) between test and reference products is recommended. In particular, in vitro permeation test (IVPT) data analysis uses a reference-scaled approach for two primary endpoints, cumulative penetration amount (AMT) and maximum flux (Jmax), which takes the within donor variability into consideration. In 2022, the Food and Drug Administration (FDA) published a draft IVPT guidance that includes statistical analysis methods for both balanced and unbalanced cases of IVPT study data. This work presents a comprehensive evaluation of various methodologies used to estimate critical parameters essential in assessing BE. Specifically, we investigate the performance of the FDA draft IVPT guidance approach alongside alternative empirical and model-based methods utilizing mixed-effects models. Our analyses include both simulated scenarios and real-world studies. In simulated scenarios, empirical formulas consistently demonstrate robustness in approximating the true model, particularly in effectively addressing treatment-donor interactions. Conversely, the effectiveness of model-based approaches heavily relies on precise model selection, which significantly influences their results. The research emphasizes the importance of accurate model selection in model-based BE assessment methodologies. It sheds light on the advantages of empirical formulas, highlighting their reliability compared to model-based approaches and offers valuable implications for BE assessments. Our findings underscore the significance of robust methodologies and provide essential insights to advance their understanding and application in the assessment of BE, employed in IVPT data analysis.

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Objectives: Body surface area (BSA) is an important parameter in clinical practice for children. To find out the most accurate BSA formula for Chinese children, nine formulas were compared. Methods: This single-center study comprised children who were diagnosed with acute lymphoblastic leukemia and treated with anticancer agents in a specialized children's hospital in China from January 2017 to December 2020. The BSA values were calculated using the formulas from Boyd, Banerjee and Bhattacharya, Costeff, Fujimoto and Watanabe, Haycock, Gehan and George, Mosteller, Stevenson and a Pediatrics textbook. The arithmetic mean of formulas was calculated as the "gold standard" for comparison. Results: A total of 666 children (389 males and 277 females) were included. All nine formulas showed a strong positive correlation with the "gold standard." Underestimation was observed with the Banerjee and Bhattacharya, Fujimoto and Watanabe formulas. The Gehan and George formula showed overestimation. Values estimated from the Haycock and Mosteller formulas were the closest to the mean BSA. Conclusion: The Haycock and Mosteller formulas are the most recommended formulas for Chinese children with hematological malignancies.

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Hardenability is one of the most basic criteria influencing the formulation of the heat treatment process and steel selection. Therefore, it is of great engineering value to calculate the hardenability curves rapidly and accurately without resorting to any laborious and costly experiments. However, generating a high-precision computational model for steels with different hardenability remains a challenge. In this study, a combined machine learning (CML) model including k-nearest neighbor and random forest is established to predict the hardenability curves of non-boron steels solely on the basis of chemical compositions: (i) random forest is first applied to classify steel into low- and high-hardenability steel; (ii) k-nearest neighbor and random forest models are then developed to predict the hardenability of low- and high-hardenability steel. Model validation is carried out by calculating and comparing the hardenability curves of five steels using different models. The results reveal that the CML model works well for its distinguished prediction performance with precise classification accuracy (100%), high correlation coefficient (≥0.981), and low mean absolute errors (≤3.6 HRC) and root-mean-square errors (≤3.9 HRC); it performs better than JMatPro and empirical formulas including the ideal critical diameter method and modified nonlinear equation. Therefore, this study demonstrates that the CML model combining material informatics and data-driven machine learning can rapidly and efficiently predict the hardenability curves of non-boron steel, with high prediction accuracy and a wide application range. It can guide process design and machine part selection, reducing the cost of trial and error and accelerating the development of new materials.

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AIM: Formulas for empirical body surface area (BSA), which is used to estimate body size and standardise physiological parameters, may disagree in children. We compared six commonly used BSA formulas-Du Bois, Boyd, Costeff, Haycock, Meban and Mosteller-in a surgical cohort. METHODS: This retrospective single-centre cohort study comprised 68 children who had corrective heart surgery at Skåne University Children's Hospital, Lund, Sweden, from February 2010 to March 2017. RESULTS: The children (51% female) underwent surgery at a mean weight of 7.0 kilograms (range 2.7-14.1 kg) and a mean age 11 months (range 0-43 months). All the BSA formulas showed good correlation with mean BSA, but there were considerable variations between them. Mosteller's formula was exactly the same as the mean BSA (bias 0.000). The Du Bois and Boyd formulas had the largest mean BSA deviations (bias -0.012 and 0.015). Costeff's formula showed good agreement with mean BSA, Haycock's formula showed minimal overestimation and Meban's formula demonstrated a systemic error in older children. CONCLUSION: Commonly used BSA formulas did not agree in young children undergoing heart surgery, but they were all close to the overall mean of the six formulas, with the Mosteller formula producing the same value.

Asunto(s)

Procedimientos Quirúrgicos Cardíacos , Superficie Corporal , Peso Corporal , Niño , Preescolar , Estudios de Cohortes , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Estudios Retrospectivos , Suecia

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The in-plane crashworthiness of multi-layer regularly arranged circular honeycombs are investigated numerically at v = 1-250 m/s, with aim to disclose the influences of t/R ratio and crushing velocity, v. A novel evaluation methodology of crashworthiness and a new mechanical term, most appropriate strain, are put forward, which results in some new evaluation parameters. The theoretical analysis shows the most appropriate strain is a significant parameter for measuring the crashworthiness. Different deformation modes cause different change rules of these evaluation parameters. Under the quasi-static homogeneous mode and transition mode, the most appropriate strain is linear with the t/R ratio for a given v; the crushing force efficiency is approximately independent of t/R and sensitive to the v; the maximum energy absorption efficiency roughly decreases and then fluctuates. With the increase of v, the crushing force efficiency first becomes smaller sharply, and then fluctuates. Under dynamic mode, the maximum energy absorption efficiency is nearly constant for a given t/R ratio. Based on the finite element results, the empirical expressions of all evaluation parameters are given. The finite element calculated results of optimal specific energy absorption are consistent with those calculated by empirical expressions, which validates all empirical expressions.

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Many standard methods used for the remote sensing of ocean colour have been developed, though mainly for clean, open ocean waters. This means that they may not always be effective in complex waters potentially containing high concentrations of optically significant constituents. This paper presents new empirical formulas for estimating selected inherent optical properties of water from remote-sensing reflectance spectra Rrs(λ), derived, among other things, for waters with high concentrations of dissolved and suspended substances. These formulas include one for estimating the backscattering coefficient bb(620) directly from the magnitude of Rrs in the red part of the spectrum, and another for estimating the absorption coefficient a(440) from the hue angle α. The latter quantity represents the water's colour as it might be perceived by the human eye (trichromatic colour vision); it is easily calculated from the shape of the Rrs spectrum. These new formulas are based on a combined dataset. Most of the data were obtained in the specific, optically complex environment of the Baltic Sea. Additional data, taken from the NASA bio-Optical Marine Algorithm Dataset (NOMAD) and representing various regions of the global oceans, were used to widen the potential applicability of the new formulas. We indicate the reasons why these simple empirical relationships can be derived and compare them with the results of straightforward modelling; possible applications are also described. We present, among other things, an example of a simple semi-analytical algorithm using both new empirical formulas. This algorithm is a modified version of the well-known quasi-analytical algorithm (QAA), and it can improve the results obtained in optically complex waters. This algorithm allows one to estimate the full spectra of the backscattering and absorption coefficients, without the need for any additional a priori assumptions regarding the spectral shape of absorption by dissolved and suspended seawater constituents.

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Determining groundwater recharge is in particular in areas with Monsoon rainfall a challenge. Several methods were used to estimate groundwater recharge for the first time ever for the urban area of Hanoi city, Vietnam. Water table fluctuation method (WTF), hydrograph analyses including recession curve displacement, graphical separation, the Automated Web GIS-Base Hydrology Analysis Tool (WHAT), and empirical formulas were utilized. The mean recharge is approximately 340 mm/year accounting for 20% of precipitation in the period 1996 to 2009 with a certain decrease during this period. Baseflow separation methods show the highest values, whereas the displacement recession curve obtains the lowest recharge. The WTF methods approximate values are close to the mean value of all other proxies. The differences between all proxies are around 10%, and Spearman correlation is statistically significant. This indicates that these methods can be used to estimate recharge for this area. With long-term data, however, the results of WTF appear more consistent and more reasonable than the other approaches.

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The critical works about nuclear science and technology depend on nuclear data. Cross section data of (n,p) and (n,α) reactions on 102,105,106,108,110Pd isotopes were calculated for projectile energies from threshold to 20 MeV. Here, the effects on nuclear excitation functions of different level density models were studied using ALICE/ASH and TALYS 1.6 computer codes. Besides, for (n,p) and (n,α) reactions in energy range of 14-15 MeV, numerous empirical formulas, obtained by various authors, were also used for predicting the cross sections. Hence, a comparison of the simulation results and experimental values was presented together with the data calculated by the empirical formulas.