Validity Of Method Research Articles

Development of an ELISA method for detection of antibodies against Mycoplasma hyopneumoniae based on Mhp336 protein

This study aims to establish an ELISA method with high specificity for the detection of antibodies against Mycoplasma hyopneumoniae. Firstly, we constructed a recombinant strain Escherichia coli BL21(DE3)-pET-32a(+)-mhp336 to express the recombinant protein Mhp336 and used the purified Mhp336 as the coating antigen. Then, we optimized the ELISA parameters, including antigen concentration, blocking buffer, blocking time, dilution of serum, incubation time with serum, secondary antibody dilution, secondary antibody incubation time, colorimetric reaction time, and cut-off value. Afterwards, reproducibility experiments were conducted, and the cross reactivity of Mhp366 with other antisera of porcine major pathogens and the maximum dilution ratios of the sera were determined. Finally, 226 porcine serum samples were detected using the method established in this study, a commercial ELISA kit for M. hyopneumoniae antibody detection, and a convalescent serum ELISA kit for M. hyopneumoniae antibody detection. The detection results of the three methods were compared to evaluate the sensitivity and specificity of the ELISA method established in this study. For this method, the optimal antigen concentration, blocking buffer, blocking time, dilution of serum, incubation time with serum, secondary antibody dilution, secondary antibody incubation time, and colorimetric reaction time were 0.05 μg/mL, PBS containing 2.5% skim milk, 1 h, 1:500, 0.5 h, 1:10 000, 1 h, and 5 min, respectively. Validation of the ELISA method based on Mhp336 showed a cut-off value of 0.332. The coefficients of variation of both intra-batch and inter-batch kits were below 7%. The detection results of porcine serum samples indicated that the method established in this study outperformed the commercial ELISA kit and the convalescent serum ELISA kit for M. hyopneumoniae antibody detection in terms of sensitivity and specificity. We successfully established an ELISA method for detecting the antibodies against M. hyopneumoniae based on Mhp336 protein. This method demonstrated high sensitivity and specificity, serving as a tool for the prevention of mycoplasmal pneumonia of swine in pig farms.

A candidate reference measurement procedure for quantification of glycocholic acid in human serum based on isotope dilution liquid chromatography-tandem mass spectrometry.

Accurate measurement of serum glycocholic acid (GCA) is crucial for evaluating the activity of chronic hepatitis. Moreover, GCA is a novel identified biomarker for hepatocellular carcinoma. Although some laboratories have used theliquid chromatography-tandem mass spectrometry (LC-MS/MS) method to measure GCA in recent years, the problem of potential interference of GCA analogues has not been solved well yet. Neither reference measurement procedures nor reference materials for GCA have been listed in the Joint Committee for Traceability in Laboratory Medicine (JCTLM) database. For standardization of GCA, it is urgent to establish a candidate measurement procedure for GCA. In this study, a candidate reference measurement procedure for the quantification of GCA in human serum based on isotope dilution liquid chromatography-tandem mass spectrometry (ID-LC-MS/MS) by a two-step sample pretreatment of protein precipitation and MAX solid-phase extraction was developed and validated. GCA can be completely separated from its structural analogues with gradient elution in 9 min compared with short time gradients published in previous literature by Huang's group. Method validation indicated perfect quantitation precision with intra-day and inter-day values that were ≤1.30% and ≤1.80%, respectively. The method showed excellent linearity with high regression coefficients (R2 > 0.999) over a range of 0.92 ng/g-38.38 μg/g and perfect recoveries at three spiked levels (99.87-100.43%). No interference, matrix effect, and carryover were observed. Moreover, the cRMP was successfully applied to measure GCA in serum samples and compared with two immunoassays in aclinical laboratory. As a candidate reference method, this method can promote aGCA standardization program.

Quality control and validation of extracellular vesicles isolated from cultured human breast cancer cells

ObjectiveExtracellular vesicles (EVs) have been shown to play a critical role in promoting tumorigenesis. As EV research grows, it is of importance to have standardization of isolation, quality control, characterization and validation methods across studies along with reliable references to explore troubleshooting solutions. Therefore, our objective with this Research Note was to isolate EVs from multiple breast cancer cell lines and to describe and perform protocols for validation as outlined by the list of minimal information for studies of EVs (MISEV) from the International Society for Extracellular Vesicles.ResultsTo isolate EVs, two techniques were employed: ultracentrifugation and size exclusion chromatography. Ultracentrifugation yielded better recovery of EVs in our hands and was therefore used for further validation. In order to satisfy the MISEV requirements, protein quantification, immunoblotting of positive (CD9, CD63, TSG101) and negative (TGFβ1, β-tubulin) markers, nanoflow cytometry and electron microscopy was performed. With these experiments, we demonstrate that yield of validated EVs varied between different breast cancer cell lines. Protocols were optimized to accommodate for low levels of EVs, and various technical and troubleshooting suggestions are included for potential application to other cell types that may provide benefit to investigators interested in future EV studies.

Validation and measurement uncertainty of analytical methods for various azo dye adulterants in Curcuma longa L.

Food adulteration involving the illegal addition of dyes to foodstuffs has become an alarming issue in recent years. This study developed and validated a high-performance liquid chromatography (HPLC)-DAD (diode array detector) method for the simultaneous determination of nine azo dyes (Butter Yellow, Sudan Orange G, Para Red, Sudan I, Sudan II, Sudan III, Sudan IV, Sudan Red 7B, and Scarlet 808). Moreover, a qualitative analysis method using liquid chromatography-tandem mass spectrometry was developed to more accurately identify peaks detected in HPLC-DAD. The calibration curve represented good linearity (r2≥0.9998) over the measured concentration range of 0.5-25mg/kg. limit of detection and limit of quantification were 0.01-0.04 and 0.04-0.12mg/kg, respectively. Accuracy and precision were 96.0-102.6 and 0.16-2.01 (relative standard deviation%), respectively. Additionally, the measurement uncertainty and HorRat value were estimated. Several Curcuma longa L. distributed in Korea were collected and monitored for azo dye contaminants. PRACTICAL APPLICATION: The proposed HPLC-DAD method represents a significant advancement in the field, offering a reliable means of quantifying azo dyes and identifying their presence even at trace levels in adulterated turmeric. This not only contributes to ensuring the safety and integrity of turmeric products but also establishes precedent for robust analytical techniques in addressing food safety challenges.

Comparison of digital study model superimposition methods using implant-supported crowns and best-fit algorithms

Research regarding orthodontic changes using the superimposition of digital study models (DSMs) is commonplace. Information regarding the accuracy of data processing by superimposition software is limited. The study aimed to compare different methods of superimposing DSMs using implant-supported crowns (ISC) as a stable reference structure. DSMs containing ISCs were sourced from a database of patients treated with clear aligner therapy. The DSM representing the planned treatment outcome was superimposed on the pretreatment DSM. Three tooth points were selected for comparison on the contralateral side of each ISC. Differences in Cartesian coordinates for each tooth point for each arch superimposition method, used by the Geomagic Control X(3D systems, Rock Hill, NC) software system, were recorded. Paired t tests for the reference standard superimposition method best-fit high-resolution using the entire dental arch compared with initial, best-fit low-resolution, and best-fit high-resolution using the ISC only were calculated. The DSMs of 54 dental arches containing ISCs were evaluated. All mean differences for displacements of selected points on the contralateral side to the ISC in the 3 Cartesian planes were<0.05 mm (P<0.05) and below the threshold of clinical significance. In addition, the standard superimposition techniques (initial, best-fit low-resolution, and best-fit high-resolution) resulted in nonstatistically significant and nonclinically significant differences in the position of the ISC. Researchers can be confident that the described superimposition methodologies, with and without ISCs as a stable reference structure, are a valid method for accurately assessing most intraarch dental changes.

UAV-Embedded Sensors and Deep Learning for Pathology Identification in Building Façades: A Review

The use of geotechnologies in the field of diagnostic engineering has become ever more present in the identification of pathological manifestations in buildings. The implementation of Unmanned Aerial Vehicles (UAVs) and embedded sensors has stimulated the search for new data processing and validation methods, considering the magnitude of the data collected during fieldwork and the absence of specific methodologies for each type of sensor. Regarding data processing, the use of deep learning techniques has become widespread, especially for the automation of processes that involve a great amount of data. However, just as with the increasing use of embedded sensors, deep learning necessitates the development of studies, particularly those focusing on neural networks that better represent the data to be analyzed. It also requires the enhancement of practices to be used in fieldwork, especially regarding data processing. In this context, the objective of this study is to review the existing literature on the use of embedded technologies in UAVs and deep learning for the identification and characterization of pathological manifestations present in building façades in order to develop a robust knowledge base that is capable of contributing to new investigations in this field of research.

Classification of African ground pangolin behaviour based on accelerometer readouts: validation of bio-logging methods

BackgroundUnderstanding how free-ranging animals behave can help in the design of optimal management strategies to both conserve species and enable individuals to express natural behaviours, maximising welfare. Animal-borne accelerometers passively collect data on body acceleration which can be interpreted to quantify behaviour. Accelerometers are increasingly used in behavioural research, however validation of accelerometer readouts to enable classification of discrete behaviours is required for each species. Pangolins are a heavily trafficked clade of mammals, all of which are considered vulnerable to extinction. They are also under-researched, with little known about their behaviour in the wild. In this study, we present the first validation of behavioural classification based on accelerometer readouts for a pangolin species; the ground pangolin (Smutsia temminckii).ResultsWe present a standardised protocol for attaching accelerometers to pangolins to minimise the impact of devices on welfare. We match the readouts from accelerometers to behaviours defined through video observations. Using a random forest classification, we defined five discrete behaviours (walking, digging, feeding, investigating ground, and stationary, accuracy of 85%) and three activity levels (low, medium, and high, accuracy of 94%) from accelerometer readouts. We determine optimal sampling frequency and window length (50 Hz and five seconds for discrete behaviour, 10 Hz and seven seconds for activity level). We then deploy accelerometers and classify the behaviour of three free-ranging pangolins for between two and four days. We find considerable variation in peak daily activity between free-ranging pangolins with different individuals displaying nocturnal and crepuscular behaviour. We also find that pangolins spend the majority of their time (between 62 and 71%) at rest.ConclusionThe methods we present will enable the quantification of ground pangolin behaviour in the wild to improve our understanding of the species’ ecology and help inform conservation efforts. This will also help to improve our fundamental understanding of animal behaviour and ecology.

Introduction of a spectrophotometric method for salivary iodine determination on microplate based on Sandell-Kolthoff reaction.

Iodine is an essential element for the synthesis of thyroid hormones. Therefore, a reliable marker of iodine supply is important. Iodine is predominantly excreted via kidneys, but also via salivary glands. Our aim was to introduce a new and simple method for determination of salivary iodine concentration (SLIC). Self-prepared chemicals and standards for Sandell-Kolthoff reaction on microplate with ammonium peroxydisulfate (AP) in the range 0-400 µg/L were used. Suitability of water-based standards (WBS) and artificial saliva-based standards (ASS) for standard curve were tested. We followed standards for method validation, defined concentration of used AP and compared our results with Inductively Coupled Plasma Mass Spectrometry (ICP-MS). WBS gave more reliable results than ASS as an underestimation of iodine concentration was found for ASS. LoB was 6.5 µg/L, LoD 12.0 µg/L, therefore analytical range was 12-400 µg/L. Intra- and inter-assay imprecisions at iodine concentrations, namely 20, 100, 165, and 350 µg/L were 18.4, 5.1, 5.7, and 2.8%, respectively, and 20.7, 6.7, 5.1, and 4.3%, respectively. Suitable molarity of AP was 1.0 mol/L and showed no difference to 1.5 mol/L (P values for samples with concentration 40, 100, and 150 µg/L, were 0.761, 0.085, and 0.275, respectively), whereas there was a significant change using 0.5 mol/L (P<0.001). Saliva samples could be diluted up to 1:8. There was no interference of thiocyanate and caffeine up to 193.5 mg/L. Our original method was comparable to ICP-MS. Spaerman coefficient was 0.989 (95% CI: 0.984-0.993). The new method for SLIC determination is in excellent agreement with ICP-MS and easy-to-use.

A simple and sensitive high-performance liquid chromatographic method combined with fluorescence detection for bioanalysis of scopoletin in rat plasma: Application to a pharmacokinetic study.

Scopoletin, a coumarin class natural phytoalexin, is present in medicinal plants such as noni (Morinda citrifolia). It exhibits diverse pharmacological properties, including antioxidant, anti-hyperuricemic, and anti-inflammatory effects. The objective of this study was to develop a novel HPLC-fluorescence (HPLC-FL) method for the quantitative analysis of scopoletin in the plasma and to investigate its pharmacokinetics in rats. Sample preparation involved a methanol-based protein precipitation method, and chromatographic separation was conducted using a C18 column with an isocratic mobile phase composed of water and acetonitrile containing 0.1% trifluoroacetic acid. The eluent was detected using an FL detector set to optimized excitation/emission wavelengths of 337/453 nm. Method validation encompassed assessments of selectivity, linearity (1-500 ng/mL), precision, accuracy, recovery, matrix effect, and stability in accordance with the prevailing Food and Drug Administration (FDA) guidelines. The developed method was successfully applied for pharmacokineticstudy in rats. To the best of our knowledge, this study is the first application of a simple and sensitive HPLC-FL method for the quantification of scopoletin in a pharmacokinetic study. This method offers a promising alternative for preclinical pharmacokinetic investigations with appropriate modifications and validations and holds potential for clinical applications.

Dissipation and dietary risk assessment of fluoxapiprolin (and its metabolites) residues in cucumber and tomato samples under field conditions

The present study was undertaken to understand the dissipation behaviour/kinetics of fluoxapiprolin and its metabolites in cucumber and tomato under field conditions. A QuEChERS based extraction method followed by liquid chromatography coupled to mass spectrometry (LC-MS/MS) analysis showed that all method validation parameters were within the acceptable range as per international standards with a limit of quantitation (LOQ) of 0.01 mg kg−1 for all analytes. As significant matrix effects were observed with a few metabolites, matrix matched standards were used for the whole study. Residues of fluoxapiprolin in cucumber at standard dose were steady from 0 to 3 day after application and were below LOQ on the 5th day after application. In cucumber fruit at double dose and in tomato at both the doses the residues followed second-order kinetics and were respectively ≤ LOQ from days 7 and 14 onwards. Pre-harvest intervals (PHI) of 5 days and 14 days are proposed for cucumber and tomato fruits respectively. All the metabolites were ≤ LOQ from day 0 in all the matrices. The consumer risk, assessed as Hazard Quotient (HQ), showed that HQ was ≤1 in all the cases. The results of the present study and earlier studies on other similar fungicides suggest that the use of fluoxapiprolin in cucumber and tomato fruits may not pose health or environmental hazards provided that good agricultural practices are followed and the proposed waiting period is observed. The data from the present study can be used by regulatory bodies in establishing maximum residue limits.

Analytical Method Development and Validation for Quantitative Estimation of Tebentafusp Bulk Dosage by RP-HPLC

Analytical Method Development and Validation for Quantitative Estimation of Tebentafusp Bulk Dosage by RP-HPLC

Hardware implementation of bearing fault diagnosis using empirical mode decomposition

ABSTRACT This paper presents a comprehensive methodology for developing a vibration measurement system, with a primary focus on monitoring rolling element bearings, widely recognised as pivotal components in generic machine vibration monitoring. Through the utilisation of sensors to capture vibration data signals, the system aims to meticulously analyse these signals to discern any indications of bearing health deterioration, thus facilitating the early identification of potential pre-breakdown conditions. The proposed system initiates the process by internally decomposing the three-axis vibration signal, enabling subsequent transmission of processed data to a remote location for the identification of specific faults in the roller element bearings. Installation of a three-axis accelerometer on the bearing housing, positioned radially, facilitates the capture of raw vibration data along one axial and two radial directions. Moreover, efforts to enhance computational efficiency involve cascading multiple identical modules in a serial pipeline structure, allowing for iterative loop computation of intrinsic mode functions within Empirical Mode Decomposition (EMD). Real-time computation is achieved through this serial pipeline structure, necessitating two distinct clock frequencies: one at 12.5 MHz for sampling and storing 3-axis vibration data in ping pong buffers, and another at 40 MHz for reading and processing the data signal retrieved from these buffers. Validation of the proposed method is demonstrated through simulation results obtained via synthesised Verilog code on Xilinx Artix-7 FPGA (XC7A35T-1CPG236C), affirming its efficacy in real-time applications.

Syntactic engagement of new words: The garden-path method applied to track sensitivity to structural ambiguity

This article proposes an innovative approach to examining garden-path (GP) effects in sentence processing. It applies GP effects as a method to a new domain, specifically to syntactic engagement of recently learned verbs. We tested twenty-seven English native speakers and twenty Spanish learners of English to verify method validity. Three main components characterise the method, namely training of new word meaning through definitions and example sentences, eye-tracking while reading plausible and implausible GP sentences after sleep consolidation, and a meaning recall test. We also examined if participants’ phonological working memory and vocabulary size play a role in how they syntactically engage new words. Results showed that recently learned verbs can elicit syntactic engagement in both native and nonnative readers. Both vocabulary size and phonological working memory capacity could predict ambiguity reprocessing, irrespective of language group. These results indicate that garden pathing can reliably signal effort to detect and resolve subject-object ambiguities in both first language (Frazier & Rayner, 1982; Pickering & Traxler, 1998) and second language readers (Chen et al., 2021, Jegerski, 2012). This feasibility study is a pioneering attempt to map new vocabulary knowledge as a window into emergent structural representations. The significance of this method lies in its potential to track syntactic engagement of new lexis, while accounting for individual differences, and following the principle that to know a word entails knowing its form, meaning, as well as its grammatical use (Nation, 2001).

The influence of different abiotic conditions on the concentrations of free and conjugated deoxynivalenol and zearalenone in stored wheat.

Environmental factors influence fungal growth and mycotoxin production in stored grains. However, the concentrations of free mycotoxins and their conjugates and how they are impacted by different interacting environment conditions have not been previously examined. The objectives of this study were to examine the impact of storage conditions (0.93-0.98 aw) and temperature (20-25°C) on (a) the concentrations of deoxynivalenol and zearalenone and their respective glucosides/conjugates and (b) the concentrations of emerging mycotoxins in both naturally contaminated and irradiated wheat grains inoculated with Fusarium graminearum. Contaminated samples were analysed for multiple mycotoxins using Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS). Method validation was performed according to the acceptable performance criteria set and updated by the European Commission regulations No. 2021/808/EC. As an important conjugate of deoxynivalenol, the concentrations of deoxynivalenol-3-glucoside were significantly different from its precursor deoxynivalenol at 0.93 aw (22% moisture content- MC) at 25°C in the naturally contaminated wheat with a ratio proportion of 56:44% respectively. The high concentrations of deoxynivalenol-3-glucoside could be influenced by the wheat's variety and/or harvested season/fungal strain type/location. Zeralenone-14-sulfate concentrations were surprisingly three times higher than Zearalenone in the naturally contaminated wheat at 0.98 aw (26% MC) at both temperatures. Emerging mycotoxins such as moniliformin increased with temperature rise with the highest concentrations at 0.95 aw and 25°C. These findings highlight the influence and importance of storage aw x temperature conditions on the relative presence of free vs conjugated mycotoxins which can have implications for food safety.

Automatic detection of sleep apnea from a single-lead ECG signal based on spiking neural network model

BackgroundSleep apnea (SLA) is a commonly encountered sleep disorder characterized by repetitive cessation of respiration while sleeping. In the past few years, researchers have focused on developing less complex and more cost-effective diagnostic approaches for identifying SLA recipients, in contrast to the cumbersome, complicated, and expensive conventional methods. MethodThis study presents a biologically plausible learning approach of spiking neural networks (SNN) with temporal coding and a tempotron learning model for diagnosing SLA disorder using single-lead electrocardiogram (ECG) data information. The proposed framework utilizes temporal encoding and the leaky integrate and fire model to transform the ECG signal into spikes for capturing the signal's dynamic pattern nature and to simulate input response behaviors. The tempoton learning technique, a spike-based algorithm, trains the SNN model to identify SLA event patterns from encoded output spike trains. This study utilized ECG data to extract heart rate variability (HRV) and ECG-derived respiration (EDR) signals from 1-min segment data of ECG records for input to SNN model. Thirty-five recordings of both released and withheld data from the Apnea-ECG databases from Physionet have been applied to train the SNN model and validate the model's efficacy in identifying SLA occurrences. ResultsThe proposed method demonstrated substantial improvements compared to other SLA detection techniques, achieving a significant accuracy of 94.63 % for per-segment detection, along with specificity, sensitivity, F1-score and AUC values of 96.21 %, 92.04 %, 0.9285, and 0.9851 respectively. The accuracy for per-recording detection achieved 100 %, with a correlation coefficient value of 0.986. Additionally, the experiment used UCD data for validation methods, achieving an accuracy of 84.573 %. ConclusionsThese results suggest the effectiveness and accessibility of the presented approach for accurately identifying SLA cases. The suggested model enhances the performance of SLA detection when contrasted with various techniques based on feature engineering and feature learning.

Test-based measurement of skill mismatch: a validation of five different measurement approaches using the NEPS

Skill mismatch is a key indicator of labour market research that has received significant attention. To date, various approaches of test-based measurement of skill mismatch have been used in research, generating differing results. However, it remains unclear which method is the most valid for measuring skill mismatch. This study provides a comparative validation of five commonly used approaches to test-based measurement of skill mismatches in reading and mathematics to detect the most valid method. Drawing on the 2016 wave of the German National Educational Panel Study (NEPS) Adult Cohort, I find significantly varying distributions for the different measurement approaches, and highly valid skill mismatch measures for the statistical and the mixed approach. Overall, the mixed approach emerges as the most valid method. The findings highlight the critical importance of measurement approaches in skill mismatch research.

LC-ESI-MS/MS methods for the quantification of hydrazine mono lactose adduct and hydrazine di lactose adduct in isosorbide dinitrate and hydralazine hydrochloride tablets

Isosorbide dinitrate and hydralazine hydrochloride tablets treat heart failure in addition to conventional therapy, prolong hospitalization for heart failure, and enhance patient-reported functional status. LC-MS/MS methods developed and validated separately for the quantification of hydrazine mono-lactose adduct and hydrazine di-lactose adduct impurities in the isosorbide and hydralazine hydrochloride tablets. Separation of hydrazine mono-lactose adduct impurity achieved on ZIC-HILIC (100 × 4.6 mm, 5 µm) column with 0.1% formic acid in water as mobile phase A and acetonitrile as mobile phase B. The HPLC method gradient elution is; Tmin/% of B: 0/90, 15/40, 15.1/90, and 20/90. The flow rate is 1.0 mL per minute, and the injection volume is 20 µL. Separation of hydrazine di-lactose adduct impurity achieved on Inertsil HILIC (150 × 4.6 mm, 5 µm) column with 10 Mm ammonium acetate in water as mobile phase A and acetonitrile as mobile phase B. The HPLC method gradient elution is; Tmin/% of B: 0/90, 15/40, 15.1/90, and 18/90. The flow rate is 1.0 mL per minute, and the injection volume is 40 µL. Method validation has demonstrated both methods are specific, sensitive, linear, precise, accurate, stable and robust.

Development and Validation of A GC-MS Method Based on Solid Phase Extraction and Derivatization for Analysis of Free and Glucuronide-Conjugated Bisphenol F in Biological Samples.

As one of the speculated bisphenols to replace bisphenol A (BPA), bisphenol F (BPF), naturally present in mustard, is structurally similar to BPA and may have similar estrogenic activity, but information on its toxicity is very limited compared to BPA. In order to support the toxicology study of BPF at Heath Canada, a gas chromatography (GC) with mass spectrometry (MS) method based on solid phase extraction and derivatization was developed for analysis of BPF in liver samples. Samples were treated with β-glucuronidase to convert BPF glucuronide to free BPF for analysis of total BPF. The method was validated for free BPF at different spiking levels, and recoveries ranged from 90.0-97.5% with relative standard deviations from 0.11-5.54%. The method was also validated for glucuronide-conjugated BPF at different spiking levels of BPF mono-β-D-glucuronide, recoveries ranged from 72.3-93.3% with relative standard deviations from 1.7-8.94%. The method was used to analyse 60 liver tissue samples from the rats dosed with BPF at different levels in a toxicology study. Free and glucuronide-conjugated BPF were not detected in any of the control samples which were not dosed with BPF (average method detection limit: 0.31 ng/g), but detected in all the other liver tissue samples with levels increasing at higher doses. The percent of glucuronide-conjugated BPF in total BPF varied among the liver samples, from as low as 9.8% to as high as 77.9%, indicating the importance of analysing biological samples for BPF in both free and conjugated forms for total exposure. A GC-MS method based on solid phase extraction and derivatization was developed for analysis of both free and glucuronide-conjugated BPF in liver samples. This method was validated not only for free BPF, but also for mono-β-D-glucuronide conjugated BPF for the first time to confirm the efficiency of the deconjugation procedure with enzyme. This method can be adapted and applied for analysis of free and glucuronide-conjugated BPF in other biological samples with appropriate validation in target sample matrices.

Development and validation of the RP-HPLC method for quantification of tavaborole.

The stability-indicating approach for tavaborole quantification was developed and validated to establish a precise, linear, accurate, and robust HPLC method. The development section includes optimizing the detection wavelength, the mobile phase ratio, and the type of column used to achieve the best possible separation and sensitivity for analysis. The chromatographic conditions were established, considering peak symmetry, resolution, and retention time. The mobile phase composition, comprising a buffer: acetonitrile (75 : 25, %v/v), with an injection volume of 15 μL, showed suitable elution and recovery at 265 nm. A constant column oven temperature of 35 °C and a 1 mL min-1 flow rate were maintained. The pH of the buffer was changed to 3.0 by using orthophosphoric acid. Linearity was observed from 5 to 1000 ppm (r2 = 1.00000). The capacity (retention) factor (k) of 3.43 was observed, indicating significant interaction and good separation. Forced degradation (FD) or stress tests were performed for chemical and physical photolytic stress conditions, and the results observed were within the specified limits. The stability in the analytical solution was observed for up to 35 hours at 5 °C, confirming the stability of the solution. Validation of the developed HPLC method confirmed the system's suitability, precision, linearity, accuracy, FD, robustness, and results. All validation criteria for the technique were within acceptable limits.

Linear Programming-Based Non-Probabilistic Reliability Bounds Method for Series Systems

Due to the difficulty of accurately predicting system reliability for many engineering structures, bounds on system reliability have received increasing attention. By dealing with structural uncertain parameters with an ellipsoid model, a linear programming-based non-probabilistic reliability bounds method is proposed in this paper for series systems. In this research, a linear programming model is first established, and then several strategies are proposed to simplify the model by removing zero design variables. Three numerical examples are presented to demonstrate the feasibility and validity of the proposed method.