Method For Quantitative Estimation Research Articles

Stability indicating RP-HPLC-UV method for quantitative estimation of isomer and other organic impurities of atopic dermatitis drug abrocitinib in drug substance and pharmaceutical dosage form using quality by design (QbD) approach

A modest, reliable, robust, stability-indicating RP-HPLC-UV method was developed and validated following ICH Q2(R2) for the separation and quantification of isomer and other organic impurities of Abrocitinib (Janus kinase inhibitor). Quality by design (QbD) approach was used to achieve the desired specifications. The chromatographic separation was achieved for impurities method of Abrocitinib within 35 min of chromatographic run time on Agilent ZORBAX Eclipse plus C18 150*4.6 mm, 3.5 µm column with gradient elution mode: time (min)/B (%): 0.01/0, 2.5/15, 8.0/20, 15.0/40, 20.0/50, 25.0/50, 25.1/0, 35.0/0 with mobile phase-A (MP-A): 10 mmol/L CH3COONH4 and acetonitrile with the ratio of 900:100 (v/v), mobile phase-B (MP-B): 10 mmol/L CH3COONH4 and acetonitrile with the ratio of 100: 900 (v/v). The detection wavelength, mobile phase flow rate, column temperature, and injection volume were used at 287 nm, 1.0 mL/min, 40 °C, and 20 µl respectively. Utilizing forced degradation and mass balance investigations, the new method’s stability-indicating properties were assessed. The developed method was validated as per ICH and found to be specific, precise, rugged, robust, accurate, linear, and with a limit of quantification values,0.0359 µg/mL for the impurity IMP-A, 0.0192 µg/mL for the impurity IMP-B, 0.0322 µg/mL for the impurity IMP-C and 0.0201 µg/mL for abrocitinib.

A novel stability indicating HPTLC method for comparative quantitative estimation of quercetin in herbal preparations

This research introduces a novel stability-indicating HPTLC (High-Performance Thin-Layer Chromatography) method for the comparative quantitative estimation of Quercetin in herbal preparations. Through extensive stability studies, the method is validated, providing a robust framework for evaluating Quercetin's stability in diverse herbal formulations. The developed method ensures accurate and reliable quantification of Quercetin, facilitating comparative analysis across various herbal preparations. Additionally, results reveal that Quercetin degraded under most tested conditions, such as acidic, alkaline, oxidative and neutral conditions underscoring the necessity for intervention by experts to eliminate such challenges and ensure product efficacy and quality in the herbal industry.

Left-Turn Lane Capacity Estimation based on the Vehicle Yielding Maneuver Model to Pedestrians at Signalized Intersections

Crossing pedestrians may significantly affect the capacity of the left-turn (LT) lane at signalized intersections while sharing the same signal phase in the left-hand traffic system, the quantitative estimation method is still not intensively discussed when considering the vehicle yielding maneuver. Despite the Road Traffic Act in Japan mandating vehicles to yield to pedestrians, instances of vehicles crossing in front of pedestrians are frequent. This study aims to refine the evaluation of LT lane capacity by introducing a novel vehicle yielding maneuver model, considering factors such as pedestrian numbers, crosswalk length, and signal timing. The model, developed using data from various Japanese crosswalks, is subjected to Monte Carlo simulation for validation. Comparative analysis with existing methods in Japanese and U.S. manuals, along with observed data, highlights the effectiveness of our model. This innovative approach has the potential to mitigate vehicle–pedestrian conflicts and reduce air pollution. By incorporating techniques such as signal optimization and two-stage crossing, our model contributes to sustainability while maintaining efficient traffic flow.

Enhancing endoscopic measurement: validating a quantitative method for polyp size and location estimation in upper gastrointestinal endoscopy

BackgroundAccurate measurement of polyps size is crucial in predicting malignancy, planning relevant intervention strategies and surveillance schedules. Endoscopists’ visual estimations can lack precision. This study builds on our prior research, with the aim to evaluate a recently developed quantitative method to measure the polyp size and location accurately during a simulated endoscopy session.MethodsThe quantitative method merges information about endoscopic positions obtained from an electromagnetic tracking sensor, with corresponding points on the images of the segmented polyp border. This yields real-scale 3D coordinates of the border of the polyp. By utilising the sensor, positions of any anatomical landmarks are attainable, enabling the estimation of a polyp’s location relative to them. To verify the method’s reliability and accuracy, simulated endoscopies were conducted in pig stomachs, where polyps were artificially created and assessed in a test–retest manner. The polyp measurements were subsequently compared against clipper measurements.ResultsThe average size of the fifteen polyps evaluated was approximately 12 ± 4.3 mm, ranging from 5 to 20 mm. The test–retest reliability, measured by the Intraclass Correlation Coefficient (ICC) for polyp size estimation, demonstrated an absolute agreement of 0.991 (95% CI 0.973–0.997, p < 0.05). Bland & Altman analysis revealed a mean estimation difference of − 0.17 mm (− 2.03%) for polyp size and, a mean difference of − 0.4 mm (− 0.21%) for polyp location. Both differences were statistically non-significant (p > 0.05). When comparing the proposed method with calliper measurements, the Bland & Altman plots showed 95% of size estimation differences between − 1.4 and 1.8 mm (− 13 to 17.4%) which was not significant (p > 0.05).ConclusionsThe proposed method of measurements of polyp size and location was found to be highly accurate, offering great potential for clinical implementation to improve polyp assessment. This level of performance represents a notable improvement over visual estimation technique used in clinical practice.

Quantitative Estimation of Vanillin content in various brands of Vanilla Flavored Custard Powder by Conductometry

A facile and cost effective conductometric method for quantitative estimation of vanillin content in various locally available brands of vanilla custard powders was performed. Background of the study was conducted taking the base of varied consumption of flavored foods. Vanillin being the choice of flavored desserts in the local region of Telangana, few brands of custard powder were analyzed conductometrically. The milk proteins were removed by precipitation using Saturated copper sulphate and the vanillin content of the various vanilla flavoured custard powder was extracted by liquid-liquid extraction using methanol as solvent.Then the extracted analyte was titrated aganist 0.00105 M NaOH (Standardized).The observed conductance readings on Y-axis and volume of NaOH added on X-axis was taken and plotted a graph and end point determined graphically at 3.5mL,4mL and 3.5mL for product-1, product-2 and product-3.The amount of vanillin content in various locally available brands of vanilla flavoured custard powders was determined. And all the data obtained in this study was within the limits according to FDA. This method is well suited for routine lab analysis and easy to perform when compared to spectroscopic methods.

Quantitative estimation method for the excavation-induced weakening effect of rock mass parameters in deep tunnels

The excavation-induced weakening effect of rock mass parameters is detrimental to the stability of deep tunnels. This study presents a quantification method for the weakening effect of rock mass parameters. In this method, the weakening factor is introduced as a quantitative index of the weakening effect of rock mass parameters, which can be calculated by the acoustic P-wave velocity measured in the surrounding rock and the Hoek–Brown criterion. Taking three deep tunnels as examples, the weakening law of rock mass parameters is investigated. The results indicate that the weakening effect is most severe near the excavation outline and gradually decays with increasing distance. Significant differences in the weakening effect can be observed at different parts of the tunnel cross-section and under different excavation methods. The weakening effect can be further exacerbated by multiple excavation disturbances. Among the strength parameters of rock masses, the weakening effect of uniaxial compressive strength is the most obvious, followed by uniaxial tensile strength, cohesive strength, and equivalent internal friction angle. The FLAC3D software is utilized to reproduce different weakening effects and analyze the energy distribution around tunnels. It is found that as the weakening effect intensifies, the accumulated elastic strain energy within the surrounding rocks gradually diminishes, and the peak elastic strain energy is at the junction of damaged and undamaged rock masses.

Quantitative Estimation of Variability in Content of Asiaticoside in Centella asiatica Linn Collected from Different Geographical Regions of India by HPLC

Centella asiatica Linn is a significant and highly valued medicinal plant in various indigenous system of medicine Ayurveda, Siddha and Unani Indian system of medicines and Chinese medicines. It is one of the chief herbs for treating skin disorder, wounds healing, gastrointestinal disorders, asthma, ulcers, leprosy, vein diseases and memory improvement. In the present study an attempt is made to develop HPLC method for qualitative and quantitative estimation of an important bio active marker Asiaticoside in Centella asiatica collected from different geographical regions of India. Three samples were collected from different geographical regions of India and analyzed by HPLC. The compound separation was achieved on C18 Eclipse, XDB, 4.6mm × 150mm, 5μm particle size column using mobile phase consisted of Acetonitrile: Buffer (25:75v/v) in isocratic elution with flow rate 1.8ml/min. The detection of analytes at 210nm was carried out by using Diode Array Detector (DAD). The comparative study was carried out for variations of Asiaticoside content in Centella Asiatica Linn Collected from different geographical regions of India i.e. Chennai (Tamilnadu), Jhansi (Uttar Pradesh) and Raniketh (Uttarakhand). The studies reveal that the maximum amount of the marker compounds Asiaticoside (0.6157%) is present in the sample collected from Chennai compare to the other regions samples.

Validated First-Order Derivative Ultraviolet Spectrophotometric Determination of Rebamipide in Pharmaceutical Products

A very simple, accurate, precise, and reproducible process has been established for the estimation of rebamipide in pharmaceuticals. The literature review suggested that no UV method for quantitative estimation of first-order derivative for the rebamipide, accordingly a method has been developed and reported. As per the need for design a novel approach to analyze the drug utilizing dimethyl formamide as a solvent was identified. Rebamipide has absorbance maxima for first order derivative 314 nm. Rebamipide drug follows Beer’s law in a range of concentration between 20 to 200 μg/mL. The recovery studies verified the proposed method’s accuracy and findings were validated in accordance with ICH recommendations. The findings were deemed to be reliable and satisfactory. As a result, the suggested method can be used to quantitatively estimate Rebamipide in ordinary analysis work

Study on quantitative estimation method of energy saving and emission reduction of renewable energy system based on fuzzy matter-element method

The quantitative estimation method of energy saving and emission reduction of renewable energy system based on fuzzy matter-element method is studied, which provides reliable basis for the popularization and use of renewable energy system in practical work. Through quantitative estimation, a scientific evaluation index system and evaluation model can be established, transforming abstract and subjective concepts of energy conservation and emission reduction into concrete and objective numerical indicators. These indicators can reflect the energy-saving and emission reduction effects of renewable energy systems, making the evaluation results scientific, comparable, and traceable. The quantitative estimation index system of energy saving and emission reduction of renewable energy system and the index judgment standard are constructed, which are mainly composed of resource utilization, energy consumption and environmental pollution. On this basis, the fuzzy matter-element quantitative estimation model of energy saving and emission reduction of renewable energy system is established based on fuzzy matter-element and entropy weight theory, and the weight of energy saving and emission reduction index of renewable energy system is determined based on information entropy, and the energy saving and emission reduction effect of renewable energy system is comprehensively and quantitatively estimated with closeness as a reliable basis and reference. The experimental results show that this method can quantitatively evaluate the energy-saving and emission reduction effects of renewable energy systems, and it is feasible to comprehensively and quantitatively evaluate the energy-saving and emission reduction effects of renewable energy systems, with a maximum emission reduction of 99%. It can provide reliable reference for the energy-saving and emission reduction of renewable energy systems.

Remaining Useful Life Prediction of Lithium-Ion Battery Based on Adaptive Fractional Lévy Stable Motion with Capacity Regeneration and Random Fluctuation Phenomenon

The capacity regeneration phenomenon is often overlooked in terms of prediction of the remaining useful life (RUL) of LIBs for acceptable fitting between real and predicted results. In this study, we suggest a novel method for quantitative estimation of the associated uncertainty with the RUL, which is based on adaptive fractional Lévy stable motion (AfLSM) and integrated with the Mellin–Stieltjes transform and Monte Carlo simulation. The proposed degradation model exhibits flexibility for capturing long-range dependence, has a non-Gaussian distribution, and accurately describes heavy-tailed properties. Additionally, the nonlinear drift coefficients of the model can be adaptively updated on the basis of the degradation trajectory. The performance of the proposed RUL prediction model was verified by using the University of Maryland CALEC dataset. Our forecasting results demonstrate the high accuracy of the method and its superiority over other state-of-the-art methods.

Exploring visitors’ visual perception along the spatial sequence in temple heritage spaces by quantitative GIS methods: a case study of the Daming Temple, Yangzhou City, China

The Daming Temple, built during 457–464 C.E., is one of the developing ancient temple heritage spaces located in Yangzhou city, P. R. China. Over the past 60 years, variation in visitors’ spatial perception along the tour routes in the temple has occurred. This research attempts to reveal the changes in visitors’ visual perception along the spatial sequences at 3 different times (i.e., 1962, 1973 and 2022). A quantitative GIS-based method, which includes analysing the distribution of visitors’ spatial preferences and spatial configuration, is proposed. Digital landscape tools and quantitative estimation methods are used, including mapping within Rhinoceros software, the kernel density estimation (KDE) method within ArcGIS software and spatial syntax analysis within DepthMap software. Extracted geodata from 500 photographs of the heritage space taken by volunteer visitors are analysed within the GIS environment. Values of the mean depth (MD) at both levels of visibility and accessibility are calculated within the visibility graph analysis (VGA) model. Comparisons between the visual preferences of the visitors and the spatial configuration along the spatial sequence are conducted. The results indicate that the spatial sequence has a significant impact on visitors’ visual preferences and tour routes. The phenomenon of spatial sequence among dynamic temporal variations and the effects of narrative spaces along the spatial sequence are highlighted and explained, which reveal the relationship between visitors’ geospatial preference and the spatial configuration of the temple. Some suggestions are put forwards for further studies on the revitalisation and management of East Asian ancient temple heritage spaces.

Estimation of charge injection at Al/LDPE interface based on space charge and external current measurement

Space charge accumulation in polymer is a key problem for the electrical aging of insulation under DC condition. Space charge accumulation is strongly determined by the charge injection rate. The estimation of charge injection with steady state current contains the extraction current and is not accurate. This paper proposes a quantitative estimation method of the charge injection at the metal/polymer interface with space charge and current simultaneous measurement. A double-layer sample with a blocking layer is employed to make a quasi-unipolar condition to remove the extraction current. In addition, the displacement current is removed by considering the change in electric field on the electrode. The relationship between the electrode electric field and the pure injection current is analyzed. It is found that the square root of electric field intensity and the logarithm of injection current at the Al/LDPE (low density polyethylene) interface are linear with each other. The coefficients β for negative and positive charge injection at Al/LDPE interface are about 8.44 × 10−24 and 8.32 × 10−24, respectively. It indicates that both negative and positive charge injection at Al/LDPE interface fit the mathematical relationship of the Poole–Frenkel effect, rather than the Schottky effect which is mostly used in the study on the charge transport at polymer/metal. The negative and positive charge injection barriers are 1.23 and 1.24 eV, respectively.

Моделирование динамики контактных взаимодействий минералов во флотационной системе

Моделирование динамики контактных взаимодействий минералов во флотационной системе

Estimating resilience of manufacturing plants to physical disruptions: Model and application

The concept of Resilience is gaining an increasing importance in industrial systems, service networks and supply chains, as it extends traditional risk assessment methods by capturing both shortterm and long-term effects of accidents and disruptions. Resilience is, in fact, both a qualitative property and a performance indicator that measures the system's ability to survive disruptive events, and rapidly restore its functionality after the disruptive event has occurred. However, while literature about systems resilience is ample, comparatively scarce attention has been devoted to the evaluation of production systems resilience. As a contribution to fill this gap, in this paper a quantitative method for resilience estimation specifically aimed at manufacturing plants is developed. The method focuses on computing resilience of the manufacturing process, according to its structure, when resources are subjected to physical damage resulting from disruptive events such as sabotage, technical accidents or natural disasters. Overall, the paper allows to assess the economic loss and duration of production interruption in any kind of manufacturing plant when subjected to damage produced by the above causes. In particular, the method enables direct assessment of the initial capacity loss following a prescribed disruptive event, and explicit estimation of the time-dependent capacity recovery path based on the actual process structure and sequence of resources restoration tasks, also allowing the quantification of resulting economic losses. In the paper, after model development, an application example is provided to show model capabilities. Facility designers and emergency managers can use this model as a decision support tool for risk assessment, and to plan emergency actions and plant refurbishment aimed at resilience enhancement.

Application of Machine Learning Techniques to Improve Multi-Radar Mosaic Precipitation Estimates in Shanghai

In this study, we applied an explainable machine learning technique based on the LightGBM method, a category of gradient boosting decision tree algorithm, to conduct a quantitative radar precipitation estimation and move to understand the underlying reasons for excellent estimations. By introducing 3D grid radar reflectivity data into the LightGBM algorithm, we constructed three LightGBM models, including 2D and 3D LightGBM models. Ten groups of experiments were carried out to compare the performances of the LightGBM models with traditional Z–R relationship methods. To further assess the performances of the LightGBM models, rainfall events with 11,483 total samples during August-September of 2022 were used for statistical analysis, and two heavy rainfall events were specifically chosen for the spatial distribution evaluation. The results from both the statistical analysis and spatial distribution demonstrate that the performance of the LightGBM 3D model with nine points is the best method for quantitative precipitation estimation in this study. Through analyzing the explainability of the LightGBM models from Shapley additive explanations (SHAP) regression values, it can be inferred that the superior performance of the LightGBM 3D model is mainly attributed to its consideration of the rain gauge station attributes, diurnal variation characteristics, and the influence of spatial offset.

A Validated High-Performance Thin-Layer Chromatography Technique for Routine Analysis of Curcumin in Four Different Species of Curcuma Viz. C. amada, C. caesia, C. longa and C. zedoaria.

In this study, we investigated a new, simple, sensitive, selective and precise high-performance thin-layer chromatography (HPTLC) fingerprint and quantitative estimation method for the routine analysis of curcumin in Curcuma species viz. Curcuma amada, Curcuma caesia, Curcuma longa and Curcuma zedoaria. Linear ascending development was carried out in a twin-trough glass chamber saturated with toluene:acetic acid (4:1; v/v with 20minutes of saturation). The plate was dried and analyzed by CAMAG TLC scanner III at white light and 366nm. The system was found to give compact spots for curcumin (Rf 0.42). The relationship between the concentration of standard solutions and the peak response is linear within the concentration range of 10-70ng/spot for curcumin. In result, curcumin was not detected in any of C. caesia extracts. The percentage of curcumin was found between 0.042 and 4.908 (%w/w) in different Curcuma species obtained by two different extraction methods viz. Soxhlet and sonication, respectively. Further, extraction via Soxhlet method is most suitable method to get higher curcumin content from rhizomes. The proposed HPTLC method may be use for routine quality testing and quantification of curcumin in Curcuma samples.

In-line quantitative estimation of ammonium polyphosphate flame retardant in polyolefins via industrial hyperspectral imaging system and machine learning

Due to developments in European legislation, several halogenated flame retardants are banned due to their toxicity, and the use of phosphor-based flame retardants in plastics is increasing. A revision of ammonium polyphosphate (APP) flame retardant revealed that it is an eye irritant and toxic, thus posing a health issue. Hence APP identification is needed for enabling safe recycling of plastic waste streams. Herein an industrial in-line method for quantitative estimation of APP in low density polyethylene (LDPE) and polypropylene (PP) is demonstrated, by using an industrial hyperspectral imaging system (955 to 1700 nm) and principal component analysis (PCA). Spectra of plastic samples with varying concentrations of APP were applied to build and calibrate a quantitative determination method. PCA and band area ratios (of selected bands) were made and fitted with continuous functions for concentration determination. The plastic samples were characterised by elemental analysis, attenuated total reflection, differential scanning calorimetry, and thermogravimetric analysis. The PCA model outperforms the band area ratio model and predicts APP concentrations between 24.3 and 1.5 wt% in LDPE (R2 = 0.98) and 20.0 and 1.7 wt% in PP (R2 = 0.97). Unknown samples with APP ranging from 23.7 to 2.7 wt% in LDPE and from 18.6 to 2.3 wt% in PP were predicted and correlated to the actual concentrations. The proposed approach is valuable for the plastic recyclers and waste management industries where inline concentration determination of flame retardants is key.

Uncertainty: qualitative and quantitative aspects

The analysis the concept of uncertainty, its origin, interpretation in various scientific fields, sources of uncertainty, qualitative and quantitative aspects of this concept, as well as approaches to quantifying uncertainty are presented. Methods of historical and comparative analysis were used in the study. The main conclusion is the necessity of taking into account the presence of uncertainty and quantification of uncertainty of the results of mathematical modeling of objects and phenomena of the surrounding world in the same way as we do when assessing measurement uncertainty of experimental data. In is shown that the interval approach to estimating uncertainty of modeling results currently seems to be the most promising. The concept of uncertainty first proposed at the beginning of the last century refers to epistemic situations involving imperfect or unknown information. This concept had only a qualitative aspect for a long time. In the second half of the twentieth century, almost simultaneously with the development of a risk-based approach in the field of technological security, there was an interest in understanding uncertainty, its origin and typification. We are indebted to metrology for giving uncertainty a quantitative aspect, in which, instead of the measurement error paradigm, a measurement uncertainty paradigm was developed, and approaches (partly controversial) to its quantitative assessment were proposed. Uncertainty is an attribute of any data obtained both experimentally or theoretically (currently, usually by mathematical modeling). In the field of experimental research, specifying the uncertainty interval of the result has long been a scientific standard and routine. The time has come to make it mandatory for the results of theoretical research. To date, three alternative methods of quantitative estimation of uncertainty have been developed: probabilistic, fuzzy and interval methods. Methods for leveling the negative features of its initial «naive» version have been proposed in modern interval analysis. It seems to be the most promising method of quantifying uncertainty of the results of mathematical modeling today.

Effect of deformation on crack extension measurement for compact tension specimen with the DCPD technique

Direct current potential drop (DCPD) technique is a crack growth monitoring technique widely used in the crack growth test of specimens in laboratory environment. Deformation of the specimen during test is one of the important factors that affect the accuracy and resolution. Because the effect of deformation on measurement is usually mixed with other factors, quantitative evaluation is difficult through experiments method only. In this work a novel quantitative estimation method combining experiment and finite element analysis has been proposed, and the effect of deformation on measurement for 316 L stainless steel compact tension specimen has been quantitatively evaluated. Through the tensile test and DCPD monitoring test of the non-cracked 316 L stainless steel plate-shaped specimen, the material mechanical property parameters and the change of potential drop caused by deformation were obtained. Then the slow tensile tests have been performed on compact tension specimens. Combined with the FE simulation of the experimental process, the effect of deformation on the potential drop under different crack length has been evaluated. The results show that the influence of deformation on the potential drop is a factor that must be considered for the crack growth monitoring experiment with high crack growth resolution. The proposed method can be used to quantitatively evaluate the influence of deformation, a factor that was usually ignored in the past, on the measurement of crack growth, which provides a method and basis for correction of crack measurement errors caused by deformation. In addition, the proposed method can be used to obtain a more accurate calibration function, which is of great significance to the improvement of the accuracy and resolution of crack growth monitoring.

Expiratory Flow and Volume Estimation Through Thermal-CO[Formula: see text] Imaging.

In this work, we introduce a quantitative non-contact respiratory evaluation method for fine-grain exhale flow and volume estimation through Thermal- CO2 imaging. This provides a form of respiratory analysis that is driven by visual analytics of exhale behaviors, creating quantitative metrics for exhale flow and volume modeled as open-air turbulent flows. This approach introduces a novel form of effort-independent pulmonary evaluation enabling behavioral analysis of natural exhale behaviors. CO2 filtered infrared visualizations of exhale behaviors are used to obtain breathing rate, volumetric flow estimations (L/s) and per-exhale volume (L) estimations. We conduct experiments validating visual flow analysis to formulate two behavioral Long-Short-Term-Memory (LSTM) estimation models generated from visualized exhale flows targeting per-subject and cross-subject training datasets. Experimental model data generated for training on our per-individual recurrent estimation model provide an overall flow correlation estimate correlation of R2=0.912 and volume in-the-wild accuracy of 75.65-94.44%. Our cross-patient model extends generality to unseen exhale behaviors, obtaining an overall correlation of R2=0.804 and in-the-wild volume accuracy of 62.32-94.22%. This method provides non-contact flow and volume estimation through filtered CO2 imaging, enabling effort-independent analysis of natural breathing behaviors. Effort-independent evaluation of exhale flow and volume broadens capabilities in pulmonological assessment and long-term non-contact respiratory analysis.