Quantitative Analysis Of Products Research Articles

Quantitative ABCD Analysis of Ayurvedic Products and Their Impact on Trust

Purpose: The main goal of the paper is to pinpoint the variables affecting consumer trust in the use of Ayurvedic products. It seeks to assess the elements that influence the model's advantages, benefits, constraints and disadvantages. The goal is to use the ABCD model to give each aspect the appropriate scores or weights. To further shed light on the intricacies of the subject, the paper also intends to use factor analysis and elementary analysis. Design: This study conducted a thorough evaluation of the literature on the ABCD analytical framework. The study was successful in identifying key influencing factors and critical constituent characteristics that contribute to customer trust in consuming Ayurvedic products by quantitative analysis involving focus group interactions and suitable weightage assignment to essential attributes. Findings: The survey found that many companies and people are adopting a fresh strategy based on sustainability or survival in order to deal with their pressing problems and find quick relief. Focus group talks were used to analyse customer trust in the use of Ayurvedic products, and the ABCD analytic framework application was heavily endorsed for its beneficial elements. The results of this model thus support the effectiveness of using Ayurvedic products. Originality/value: The survey found that many companies and people are adopting a fresh strategy based on sustainability or survival in order to deal with their pressing problems and find quick relief. Focus group talks were used to analyse customer trust in the use of Ayurvedic products, and the ABCD analytic framework application was heavily endorsed for its beneficial elements. The results of this model thus support the effectiveness of using Ayurvedic products. Paper Type: Empirical Paper.

Photovoltaic Production Management under Constrained Regulatory Requirements: A Step towards a Local Energy Community Creation

Addressing the urgent need for sustainable energy sources due to the high costs and environmental impacts of fossil fuels, this research explores the integration of decentralized solar photovoltaic (PV) systems in urban Southern European settings. Specifically, we examine the effectiveness of a solar carport PV installation at a higher education institution, focusing on the challenges of energy surplus management within regulated markets that restrict grid energy injection. Our study employed a mixed-methods approach, combining quantitative data analysis of energy production with qualitative assessments of regulatory frameworks. The innovative aspect of our method lies in the development of a smart management system tailored to circumvent legal barriers, ensuring optimal use of locally produced energy and fostering the creation of an energy community with shared energetic, environmental, and social benefits. Preliminary results demonstrate that our system not only prevents energy loss but also enhances investment return by enabling the institution to become an energy prosumer within its community. A comparative analysis with traditional energy exercises reveals that our approach significantly improves energy self-sufficiency and sustainability, positioning decentralized PV systems as a viable solution in similar urban contexts.

Quantitative and Qualitative Analysis of Neurotransmitter and Neurosteroid Production in Cerebral Organoids during Differentiation.

In the human brain, neurophysiological activity is modulated by the movement of neurotransmitters and neurosteroids. To date, the similarity between cerebral organoids and actual human brains has been evaluated using comprehensive multiomics approaches. However, a systematic analysis of both neurotransmitters and neurosteroids from cerebral organoids has not yet been reported. Here, we performed quantitative and qualitative assessments of neurotransmitters and neurosteroids over the course of cerebral organoid differentiation. Our multiomics approaches revealed that the expression levels of neurotransmitter-related proteins and RNA, including neurosteroids, increase as cerebral organoids mature. We also found that the electrophysiological activity of human cerebral organoids increases in tandem with the expression levels of both neurotransmitters and neurosteroids. Our study demonstrates that the expression levels of neurotransmitters and neurosteroids can serve as key factors in evaluating the maturity and functionality of human cerebral organoids.

Development progress of stationary phase for supercritical fluid chromatography and related application in natural products

Supercritical fluid chromatography (SFC) is an environment-friendly and efficient column chromatography technology that was developed to expand the application range of high performance liquid chromatography (HPLC) using a supercritical fluid as the mobile phase. A supercritical fluid has a temperature and pressure that are above the critical values as well as relatively dynamic characteristics that are between those of a gas and liquid. Supercritical fluids combine the advantages of high solubility and diffusion, as their diffusion and viscosity coefficients are equivalent to those of a gas, while maintaining a density that is comparable with that of a liquid. Owing to the remarkable compressibility of supercritical fluids, analyte retention in SFC is significantly influenced by the density of the mobile phase. Thus, the column temperature and back pressure are crucial variables that regulate analyte retention in SFC. Increasing the back pressure can increase the density and solubility of the mobile phase, leading to reductions in retention time. The column temperature can affect selectivity and retention, and the degree to which different analytes are affected by this property varies. On the one hand, increasing the temperature reduces the density of the mobile phase, thereby extending the retention time of the analytes; on the other hand, it can also increase the energy of molecules, leading to a shorter retention time of the analyte on the stationary phase. CO2, the most widely employed supercritical fluid to date, presents moderate critical conditions and, more importantly, is miscible with a variety of polar organic solvents, including small quantities of water. In comparison with the mobile phases used in normal-phase liquid chromatography (NPLC) and reversed-phase liquid chromatography (RPLC), the mobile phase for SFC has a polarity that can be extended over a wide range on account of its extensive miscibility. The compatibility of the mobile phase determines the diversity of the stationary phase. Nearly all stationary phases for HPLC, including the nonpolar stationary phases commonly used for RPLC and the polar stationary phases commonly used for NPLC, can be applied to SFC. Because all stationary phases can use the same mobile-phase composition, chromatographic columns with completely different polarities can be employed in SFC. The selectivity of SFC has been effectively expanded, and the technique can be used for the separation of diverse analytes ranging from lipid compounds to polar compounds such as flavonoids, saponins, and peptides. The choice of stationary phase has a great impact on the separation effect of analytes in SFC. As new stationary phases for HPLC are constantly investigated, specialized stationary phases for SFC have also been continuously developed. Researchers have discovered that polar stationary phases containing nitrogen heterocycles such as 2-EP and PIC are highly suitable for SFC because they can effectively manage the peak shape of alkaline compounds and provide good selectivity in separating acidic and neutral compounds.The development of various stationary phases has promoted the applications of SFC in numerous fields such as pharmaceuticals, food production, environmental protection, and natural products. In particular, natural products have specific active skeletons, multiple active groups, and excellent biological activity; hence, these materials can provide many new opportunities for the discovery of novel drugs. According to reports, compounds related to natural products account for 80% of all commercial drugs. However, natural products are among the most challenging compounds to separate because of their complex composition and low concentration of active ingredients. Thus, superior chromatographic methods are required to enable the qualitative and quantitative analysis of natural products. Thanks to technological improvements and a good theoretical framework, the benefits of SFC are gradually becoming more apparent, and its use in separating natural products is expanding. Indeed, in the past 50 years, SFC has developed into a widely used and efficient separation technology. This article provides a brief overview of the characteristics, advantages, and development process of SFC; reviews the available SFC stationary phases and their applications in natural products over the last decade; and discusses prospects on the future development of SFC.

Quantitative Electrochemistry-Mass Spectrometry: Real-Time Detection of Volatile Products for Electrocatalysis and Batteries

A major challenge both within electrocatalysis and battery research concerns the real-time (i) identification and (ii) quantification of volatile reaction products as a function of the applied electrochemical parameters and the reaction conditions. Analysis of both steadily evolving gases and of fast- and transient reaction phenomena can reveal key insights into reaction mechanisms. To this end, methods like Differential Electrochemical Mass Spectrometry (DEMS)1 and On-line Electrochemical Mass Spectrometry (OLEMS)2 have been used successfully to study reaction mechanisms to an ever-increasing degree in recent years, primarily in aqueous electrolytes. Similarly, Online Electrochemical Mass Spectrometers (OEMS)3 have been essential for the study of gas evolution in batteries.However, to gain an in-depth understanding of these mechanisms, the ability to accurately relate the electrochemical charge transferred in the reaction to the amount of evolved product is essential. To this end, accurate calibration of MS signals is paramount. Calibration procedures available for DEMS systems are by themselves cumbersome and unreliable and full quantification is not possible for OLEMS.Herein, we show how a simple gas-based calibration procedure using chip-based Electrochemistry-Mass Spectrometry (EC-MS) can be used for reliable, fully quantitative real-time analysis of volatile electrochemical reaction products. We validate this calibration with electrochemistry-based calibration methods described previously.4,5 The new procedure allows to extend the quantitative analysis to systems with no a priori knowledge of faradaic efficiencies. We demonstrate calibration of important gases like H2, O2 and C2H4 in aqueous and non-aqueous electrolytes and exemplify the calibration methodology’s usefulness on standard electrochemical reactions. References H. Baltruschat, J Am Soc Mass Spectrom, 15, 1693–1706 (2004).A. H. Wonders, T. H. M. Housmans, V. Rosca, and M. T. M. Koper, J Appl Electrochem, 36, 1215–1221 (2006).N. Tsiouvaras, S. Meini, I. Buchberger, and H. A. Gasteiger, J Electrochem Soc, 160, A471–A477 (2013).D. B. Trimarco et al., Electrochim Acta, 268 (2018).S. B. Scott, PhD thesis, Technical University of Denmark (2019). Figure 1: a) Schematic of the MS inlet chip’s working principle. b) Uncalibrated M2 and M32 signals (dotted lines) and the same signals after calibration for H2 and O2 (full lines) in a cyclic voltammogram of PtPoly in 0.1 M HClO4 obtained at room temperature at 20 mV/s. Figure 1

Qualitative and Quantitative Means of Production of Biogas from Biodegradable Waste (Cow Dung) for Sustainable Energy

Aims: This study was carried out by analyzing the quantitative and qualitative of the biogas produced from cow dung by degrading mechanism. 32L of bioreactors was used for the study.
 Methodology: The bioreactors were constructed to imitate the fixed batch prototype. The study lasted for 30 days and it was carried out at the National Centre for Energy Research and Development, University of Nigeria,Nsukka. Slurry was prepared in bioreactors. The substrates in the bioreactors were water and cow dung (intestinal and abdominal waste). The pH, the total solids (TS), volatile solids (VS) and total volatile fatty acid (VFA) characteristics of the substrate before and after digestion were determined using standard method. Quantitative and qualitative analysis of biogas production was by liquid displacement and gas Analyzer methods
 Results: The results of the TS, VS and VFA were 400 mg/l, 92mg/l and 16.7 mg/l respectively in the predigested samples and 92 mg/l, 17.4mg/l and 28.3mg/l respectively in the post digested samples. The quantity of biogas produced at the first week was 8.5liters, 7.5litre and 6.1liter from the 4th day, 5th day and 8th days. The qualitative analysis showed that the prominent biogas produced was methane. 
 Conclusion: The results of the research concluded that high quantity of biogas can be produced using cow dung. Approaches and technology for more efficient biogas producing consortia are proposed.

Differences in Connected Speech Outcomes Across Elicitation Methods

ABSTRACT Background Connected speech is often used to assess many aspects of an individual’s language abilities after stroke. However, it is unknown the degree to which elicitation methods differ in generating structural and syntactic aspects of connected speech, two critical components of successful communication. Quantifying the degree to which elicitation methods differ in eliciting structurally, syntactically, and lexically complex connected speech at the earliest stage of stroke before reorganization and rehabilitation of function independent of clinical diagnosis of aphasia has not been examined to date. Addressing this gap has implications for early clinical intervention as well as empirical studies of connected speech production. Aims We compared two common elicitation methods, picture description and storytelling on lexical, structural, and syntactic measures of connected speech in speakers during the acute stage of left hemisphere stroke. Methods & Procedures We measured connected speech using an automated quantitative production analysis approach (Fromm et al., 2021) in 71 native-English speaking participants (27 female; 59 ± 13 years) within an average 3.9 days from left hemisphere stroke onset. We tested the degree of agreement and consistency between elicitation methods for lexical, structural, and syntactic measures of connected speech, as well as the degree of concordance in classifying deficits across individuals. Outcomes & Results Storytelling elicited significantly more words and more structurally complex, lexically diverse, and syntactically accurate speech in comparison to picture description. Elicitation methods differed in measuring outcomes across participants for the lexical and syntactic, but not structural complexity aspects of connected speech where storytelling classified more participants with impairments in comparison to picture description. Conclusions These differences suggest storytelling provides assessment of connected speech abilities more reflective of real-world abilities where its use is particularly critical for examining individual differences and providing diagnoses of acute stroke language deficits. As a result, using storytelling as a connected speech elicitation method more effectively captures a patient’s language capabilities after stroke, consequently informing clinical diagnosis and treatment.

Comparative Study of Densitometry and Videodensitometry for Quantitating the Active Pharmaceutical Ingredients Using Thin Layer Chromatography – Systematic Review

Background: Chromatography is one of the analytical techniques widely used for the quality control process in the pharmaceutical industry. One of the analytical methods used in drug analysis is Thin Layer Chromatography (TLC). The analysis process of TLC can be performed using densitometry (scanner) or videodensitometry (videoscan). The principal analysis of densitometry (scanner) is based on the density measured from each spot on the TLC plate using a specific wavelength range, and videodensitometry (videoscan) is performed by taking pictures of the plate using a Visualizer at a specific wavelength. Objective: This review article discusses the application of densitometry and videodensitometry methods for quantitative analysis of pharmaceutical products. Methods: This study was conducted using a systematic review method using the PRISMA statement from January to April 2023. Four databases were searched: PubMed, ScienceDirect, Scopus, and Google Scholar with inclusion criteria: studies on thin layer chromatography analysis using densitometry and videodensitometry. Results: Based on the ten articles in this study, it is known that the active ingredient concentrations in pharmaceutical products can be determined using densitometry and videodensitometry. The statistical analysis results show no significant difference between the two methods' chemical concentrations of active ingredients in pharmaceutical products. Conclusion: TLC densitometry and videodensitometry is a valid methods analysis that can be used for quantitating the active pharmaceutical ingredient concentration in finished pharmaceutical products.

Study on Mechanism of MSWI Fly Ash Solidified by Multiple Solid Waste-Based Cementitious Material Using the Rietveld Method

A novel multiple solid waste-based cementitious material (MSWCM) was developed to immobilize municipal solid waste incineration (MSWI) fly ash. The compressive strength of MSWCM with different ratios of MSWI fly ash reached the standard requirements after curing for 28 days. X-ray powder diffraction (XRD) in combination with the Rietveld method was employed to investigate the content and phase transformation of hydration products. The main hydration products of pure MSWCM paste were C-S-H, hydroxyapatite, ettringite and C-A-S-H. With increases in curing time, the content of ettringite and C-A-S-H increased significantly. The main hydration products of MSWCM paste with MSWI fly ash were C-S-H and Friedel’s salt. The contents increased markedly with increased curing time from 21.8% to 28.0% and from 8.53% to 16.7%, respectively. Additionally, a small amount of PbHPO4 (0.51–0.96%) and lead phosphate Pb3(PO4)2 (0.14–0.51%) were detected, indicating that phosphate had an effective curing effect on lead ions. The results showed that most of the hydration reactions had started at the initial stage of curing and reacted quickly to form a large number of hydration products. The quantitative analyses of hydration products provide essential information for understanding the immobilization mechanism of MSWI fly ash in MSWCM paste.

Guidelines for extraction and quantitative analysis of phytosterols and oxidation products

AbstractPhytosterols (PS) are widely distributed in the plant source foods, and research on their health benefits has become increasingly active. This article briefly outlines the main extraction processes of PS and instrumental analysis methods of PS in detail. The PS isolation technique depends on the nature of the matrix and the form of the PS (free, esterified, and glycosylated). Conventional extraction technologies for PS commonly used in practice were Soxhlet extraction and maceration method. Due to their inherent molecular structure, PS exhibits poor stability to heat, light, oxygen, pH, and metal ions. It is of great significance to find a reliable analytical technique to extract PS and oxidation products from food substances and an accurate detection method of PS in different foods due to the instability of plant sterol and the interference of complex plant‐based matrices. Generally, it is common to use GC–MS to determine the composition of total PS and their oxidation products, which requires standard monomer PS. It is desirable to use LC–MS to determine free PS in liquid samples. These methodologies could be meaningful in the quality assessment, health function evaluation, and applications and limitations of plant‐sourced foods.

TRANSITION FROM THE PLASTIC MODE OF DIAMOND GRINDING OF CERAMICS TO MELTING AND FEATURES OF THE MELTING OF INSTRUMENTAL CERAMICS

It is shown that the traditional method of estimating the specific energy capacity based on the ratio of grinding power to processing productivity does not provide an adequate solution, since with it the specific heat capacity of processing exceeds the specific heat capacity of melting ceramics by almost an order of magnitude, and therefore, any diamond processing of ceramics should immediately enter the plasticity regime, which is not really the case. Therefore, it is the application of a new approach to the assessment of the specific energy intensity of diamond grinding, taking into account the wear of the working layer of the diamond wheel, that makes it possible to assess the possibility of achieving the energy conditions for the transition of ceramic processing to the plastic mode.
 It is shown that the plastic mode occurs precisely when the specific energy capacity of grinding becomes close to the specific heat capacity of melting ceramics.
 It was found that similar to the processes during the thermal melting of ceramics, melting crusts are also formed in the discharge hole during electroerosion grinding. Quantitative analysis of melting products shows that a structure close to the fracture of the sample is formed in the discharge holes after melting, in which there is no oxygen.

An Optimized Two-Dimensional Quantitative Nuclear Magnetic Resonance Strategy for the Rapid Quantitation of Diester-Type C19-Diterpenoid Alkaloids from Aconitum carmichaelii.

With the development of nuclear magnetic resonance (NMR) spectrometers and probes, two-dimensional quantitative nuclear magnetic resonance (2D qNMR) technology with a high signal resolution and great application potential has become increasingly accessible for the quantitation of complex mixtures. However, the requirement that the relaxation recovery time be equal to at least five times T1 (longitudinal relaxation time) makes it difficult for 2D qNMR to simultaneously achieve high quantitative accuracy and high data acquisition efficiency. By comprehensively using relaxation optimization and nonuniform sampling, we successfully established an optimized 2D qNMR strategy for HSQC experiments at the half-hour level and then accurately quantified the diester-type C19-diterpenoid alkaloids in Aconitum carmichaelii. The optimized strategy had the advantages of high efficiency, high accuracy, good reproducibility, and low cost and thus could serve as a reference to optimize 2D qNMR experiments for quantitative analysis of natural products, metabolites, and other complex mixtures.

A Versatile and Easy Method to Calibrate a Two-Compartment Flow Cell for Differential Electrochemical Mass Spectrometry Measurements.

Online techniques for the quantitative analysis of reaction products have many advantages over offline methods. However, owing to the low product formation rates in electrochemical reactions, few of these techniques can be coupled to electrochemistry. An exception is differential electrochemical mass spectrometry (DEMS), which gains increasing popularity not least because of its high time resolution in the sub-second regime. DEMS is often combined with a dual thin-layer cell (a two-compartment flow cell), which helps to mitigate a number of problems that arise due to the existence of a vacuum|electrolyte interface. However, the efficiency with which this cell transfers volatile reaction products into the vacuum of the mass spectrometer is far below 100%. Therefore, a calibration constant that considers not only the sensitivity of the DEMS setup but also the transfer efficiency of the dual thin-layer cell is needed to translate the signals observed in the mass spectrometer into electrochemical product formation rates. However, it can be challenging or impossible to design an experiment that yields such a calibration constant. Here, we show that the transfer efficiency of the dual thin-layer cell depends on the diffusion coefficient of the analyte. Based on this observation, we suggest a two-point calibration method. That is, a plot of the logarithm of the transfer efficiencies determined for H2 and O2 versus the logarithm of their diffusion coefficients defines a straight line. Extrapolation of this line to the diffusion coefficient of another analyte yields a good estimate of its transfer efficiency. This is a versatile and easy calibration method, because the transfer efficiencies of H2 and O2 are readily accessible for a large range of electrode-electrolyte combinations.

Pioneering practical direct sea water splitting via an intrinsically-selective chlorine-phobic nickel polysulphide nanostructured electrocatalyst for pure oxygen evolution

Direct sea water splitting as a source of clean and uninterrupted energy source is an unparalleled approach to sustainable development. Chlorine oxidation, however, strongly limits its usage and thus requests novel avenues to create chlorine-repelling electrocatalysts for pure oxygen evolution under direct-sea water conditions. Herein, for the first time, a NiS2pSxsurface (catenated sulphur type Ni polysulfide)-based binder-free, 3D electrocatalyst is established as an excellent oxygen evolution reaction (OER) catalyst under un-buffered neutral water conditions, exhibiting a remarkably decreased overpotential (Δη∼320 mV) in comparison to nowadays accepted noble metal IrO2 catalyst. This overpotential value (∼ 360 mV, lowest ever reported in the literature) is lower than the limit for chlorine evolution in neutral conditions, thus furnish a potential platform for intrinsically chlorine-phobic OER electrocatalysis for direct sea water splitting. Surprisingly, quantitative analysis of electro-oxidation products in 0.5 M NaCl using our NiS2pSxsurface electrocatalyst demonstrates the sole formation of pure oxygen, without any chlorine, which is inevitable when using IrO2 and Pt as catalysts. The intrinsic ion-selective behavior of our electrocatayst is related to limited exposure of the sterically and electrostatically hindered Ni metal centers to large Cl- ions, thus selectively evolving oxygen. Furthermore, the fast electrochemical evolution of the NiS2pSxsurface surface to form catenated sulphur type polysulphides species (pSn2-/ S2-=2.1) further enhances the intrinsic chlorine-phobicity of the catalyst, displaying pure oxygen evolution even at noteworthy current densities up to 300 mA/cm2. This is the first demonstration of intrinsically chlorine-phobic catalytic electrodes for the “direct” sea water splitting, displaying unprecedented electrochemical performances and stability, which further opens new paths towards engineering the electrocatalysts surface aiming for intrinsically ion-selective electrodes for various applications.

Experimental investigation on decomposition characteristics of doxycycline in wastewater using hydrothermal treatment: Exploring the way to complete decomposition

Doxycycline is widely found in medical and aquaculture wastewater, posing a great threat to the ecological environment. In this study, the doxycycline was decomposed by hydrothermal method, and its decomposition properties and paths were analyzed. By using univariate experimental method, the influence of hydrothermal temperature (100–340 °C), hydrothermal time (30–120 min) and mass concentration (1–4 wt%) on the decomposition rate of doxycycline, chemical oxygen demand and nitrogen distribution in the product were studied, and the Pearson correlation coefficient of chemical oxygen demand, Total nitrogen and doxycycline removal rate was obtained. The results showed that the removal rate of doxycycline increased with the hydrothermal temperature, decreased with the reactant concentration, and increased first and then decreased with the hydrothermal time. The quantitative relation between the removal rate of doxycycline and operation conditions (temperature, time, and concentration) was obtained by using the response surface method, and the optimization conditions of the hydrothermal decomposition of doxycycline were gotten. The averaged removal rate of doxycycline reached 99.5% at temperature of 260 °C, reaction time of 102.2 min, and mass concentration of 1.4 wt%. Finally, the liquid chromatography and mass spectrometry were used for quantitative and qualitative analysis of liquid products, and three potential hydrothermal decomposition routes of doxycycline were proposed. This study will lay the foundation for the hydrothermal treatment of medical and aquaculture wastewater containing antibiotics.

Mechanistic Studies of Aziridine Formation Catalyzed by Mononuclear Non-Heme Iron Enzymes.

Aziridines are compounds with a nitrogen-containing three-membered ring. When it is incorporated into natural products, the reactivity of the strained ring often drives the biological activities of aziridines. Despite its importance, the enzymes and biosynthetic strategies deployed to install this reactive moiety remain understudied. Herein, we report the use of in silico methods to identify enzymes with potential aziridine-installing (aziridinase) functionality. To validate candidates, we reconstitute enzymatic activity in vitro and demonstrate that an iron(IV)-oxo species initiates aziridine ring closure by the C-H bond cleavage. Furthermore, we divert the reaction pathway from aziridination to hydroxylation using mechanistic probes. This observation, isotope tracing experiments using H218O and 18O2, and quantitative product analysis, provide evidence for the polar capture of a carbocation species by the amine in the pathway to aziridine installation.

Rapid quantitative analysis of calcium in infant formula powder assisted by long short-term memory with variable importance using laser-induced breakdown spectroscopy.

Calcium is the main mineral responsible for healthy bone growth in infants. Laser-induced breakdown spectroscopy (LIBS) was combined with a variable importance-based long short-term memory (VI-LSTM) for the quantitative analysis of calcium in infant formula powder. First, the full spectra were used to establish PLS (partial least squares) and LSTM models. The R2 and root-mean-square error (RMSE) of the test set (R P2 and R M S E P) were 0.1460 and 0.0093 in the PLS method, respectively, and 0.1454 and 0.0091 in the LSTM model, respectively. To improve the quantitative performance, variable selection based on variable importance was introduced to evaluate the contribution of input variables. The variable importance-based PLS (VI-PLS) model had R P2 and R M S E P of 0.1454 and 0.0091, respectively, whereas the VI-LSTM model had R P2 and R M S E P of 0.9845 and 0.0037, respectively. Compared with the LSTM model, the number of input variables in the VI-LSTM model was reduced to 276, R P2 was improved by 114.63%, and R M S E P was reduced by 46.38%. The mean relative error of the VI-LSTM model was 3.33%. We confirm the predictive ability of the VI-LSTM model for the calcium element in infant formula powder. Thus, combining VI-LSTM modeling and LIBS has great potential for the quantitative elemental analysis of dairy products.

Untargeted screening, quantitative analysis, and toxicity estimation of degradation products of fluazinam in vegetables

Fluazinam exhibits rapid degradation in some vegetable matrixes. The degradation products may pose risk for human health. In the present study, three degradation products of fluazinam in vegetables have been identified, named as sulfhydryl fluazinam, hydroxyl fluazinam, and amine fluazinam. Among them, sulfhydryl fluazinam has not been previously reported. Quantitative/semi-quantitative method for simultaneous analysis of fluazinam and the three degradation products was developed using QuEChERS in combination of HPLC-MS/MS. The proposed analytical method was further applied in monitoring fluazinam and its degradation products in fluazinam-processed vegetables. As a result, sulfhydryl fluazinam was demonstrated to be a characteristic degradation product of fluazinam in the sulphur-rich vegetables with transformation rates of above 10.0% within 60.0 min. In addition, we found for the first time that sulfhydrylation of pesticide occurred in putrid vegetable samples covering various plant families. The result contributed to discovery of the overlooked degradation pathways of pesticides in vegetables. Among fluazinam and the three degradation products, amine fluazinam was predicted to have highest toxicity, followed by sulfhydryl fluazinam and fluazinam, whereas hydroxyl fluazinam displayed the lowest toxicity. Cytotoxicity experiments in BRL-3A cells showed that toxicity of sulfhydryl fluazinam was comparable to that of fluazinam. In short-term oral studies in mice, liver appeared to be a target organ for sulfhydryl fluazinam. The present study not only provides an efficient analysis method, but also inspires further comprehensive risk assessment of fluazinam and its degradation products in vegetables.

Quantitative analysis of pharmaceutical products by spectrophotometry in the infrared region: a practical review

Quality control in the chemical-pharmaceutical industry to identify and quantify the active ingredient has fundamental importance to guarantee the quality of the final product. Its lack can generate irreparable consequences, and therefore its existence is extremely important. However, currently, in this process there is an ecologically correct need beyond the choice of the ideal method and the ideal conditions. This mini-review contemplates the current technological vision of pharmaceutical analysis through Green Analytical Chemistry (GAC). Green and sustainable methods have a main focus providing economic, environmental and social benefits. An example is spectrophotometry in the infrared region for quantitative purposes. The purpose of this mini-review is to show a practical guide for the quantitative analysis of raw materials and pharmaceutical products by spectrophotometry in the infrared region in order to contribute to a sustainability cycle, where the guarantee of product quality and the analytical awareness about health, time, waste generation, environment and cost coexist. A practical review for quantitative analysis by spectrophotometry in the infrared region was shown. It is useful for routine analysis of pharmaceutical products in general, and it can be used by chemical-pharmaceutical laboratories around the world.

611: HOST IMMUNE ENDOTYPING IN PEDIATRIC ACUTE RESPIRATORY FAILURE

Introduction: Acute respiratory failure (ARF) is a common reason for admission to the pediatric intensive care unit (PICU). The ability to immune endotype critically ill children with ARF to understand if adaptive or innate defects belie severity of illness, and then modulate these defects by evaluating therapies in an ex vivo fashion may be paradigm shifting. We have previously shown that T-cell IFN-γ (adaptive) and monocyte TNF-α (innate) production, as quantitated by the Enzyme-Linked Immune Absorbent Spot (ELISpot) assay, reflect immune competence in COVID-19 pneumonia, and illness severity is associated with decreased circulating lymphocytes with innate and adaptive immune suppression, evidenced by decreased IFN-ɣ and TNF-α production. This promising approach may have significant benefits in critically ill children, as it is unknown if specific measures of innate and adaptive immune function correlate with illness severity. We hypothesize that serial quantitative analysis of IFN-γ and TNF-α production by ELISpot will accurately reflect host immune status in critically ill children with ARF. Methods: In this IRB approved prospective cohort study, children admitted to the PICU with ARF had serial blood analysis using ELISpot for IFN-γ and TNF-α production after positive stimulus with CD3/28 and LPS respectively. ELISpot reporting for cytokine production is done as number of cells secreting the relevant cytokine; data was compared to relevant patient metadata and clinical outcomes. Results: We are currently enrolling patients, and have analyzed two patients with ARF secondary to pneumonia. Patient 1 had 19 cells secreting IFN-ɣ on day 1 and 69 cells on day 5; and 582 cells secreting TNF-α on day 1 and 1217 cells on day 5. Patient 2 had 18 cells secreting IFN-ɣ on day 1 and 144 cells on day 5; and 189 cells secreting TNF-α on day 1 and 466 cells on day 5. Conclusions: Preliminary analysis of IFN-γ and TNF-α production by ELISpot shows surprisingly more IFN-γ reduction early in disease course, which may be a driver of viral replication and severity of illness. Over 5 days, both patients had appropriately hyper inflammatory innate responses. With improved power and additional time points, there is potential to introduce adaptive stimulants early in disease trajectory that may alter clinical outcomes.