Mechanism Of Products Research Articles

The application of the SPOC teaching model in college elective basketball courses: integrating biomechanical principles for enhanced performance

The SPOC (Small Private Online Course) model is a new teaching model derived from Massive Open Online Courses (MOOC) and is an important direction for the reform and innovation of future higher education. In the practical application of SPOC teaching, subjectivity issues may arise, namely the influence of individual opinions and judgment criteria. The evaluation may focus on certain aspects and neglect others, resulting in incomplete overall assessment results. This paper applies the SPOC teaching model in three time periods: before class, during class, and after class, with a focus on integrating biomechanical principles into the evaluation of student performance in basketball. The study employs various research methods such as literature review, Analytic Hierarchy Process (AHP) analysis, and fuzzy comprehensive evaluation to construct a comprehensive evaluation index system for student ability improvement in SPOC teaching in higher education. This system incorporates biomechanical factors such as movement efficiency, force production, and body mechanics, which are essential for enhancing basketball skills. Based on this, an evaluation method for student ability improvement in college SPOC elective basketball courses is proposed using the AHP-fuzzy evaluation model. This model not only assesses traditional skill metrics but also integrates biomechanical assessments, such as shooting mechanics, dribbling efficiency, and defensive posture. The application of the AHP-fuzzy evaluation model, enhanced with biomechanical insights, demonstrates that his method can effectively improve students basketball abilities. The incorporation of biomechanical principles allows for a more holistic evaluation of student performance, emphasizing the importance of physical mechanics in skill development. The integration of the SPOC teaching model with biomechanical principles in elective basketball courses provides a comprehensive framework for evaluating and improving student performance. By focusing on both skill acquisition and biomechanical efficiency, this approach not only enhances basketball abilities but also fosters a deeper understanding of the physical demands of the sport.

Decoding nature: multi-target anti-inflammatory mechanisms of natural products in the TLR4/NF-κB pathway

Natural products are valuable medicinal resources in the field of anti-inflammation due to their significant bioactivity and low antibiotic resistance. Research has demonstrated that many natural products exert notable anti-inflammatory effects by modulating the Toll-like receptor 4 (TLR4) and nuclear factor kappa B (NF-κB) signaling pathways. The research on related signal transduction mechanisms and pharmacological mechanisms is increasingly being discovered and validated. However, there is currently a lack of comprehensive reviews focusing on the pharmacological mechanisms of natural products targeting the TLR4/NF-κB pathway for anti-inflammatory effects. In light of these considerations, this review comprehensively synthesizes recent research findings concerning the TLR4/NF-κB signaling pathway, including the translocation of TLR4 activation to lysosomes within the cytoplasm, the assembly of protein complexes mediated by ubiquitin chains K63 and K48, and the deacetylation modification of p65. These discoveries are integrated into the classical TLR4/NF-κB pathway to systematically elucidate the latest mechanisms among various targets. Additionally, we summarize the pharmacological mechanisms by which natural products exert anti-inflammatory effects through the TLR4/NF-κB pathway. This aims to elucidate the multitarget advantages of natural products in the treatment of inflammation and their potential applications, thereby providing theoretical support for molecular pharmacology research on inflammation and the development of novel natural anti-inflammatory drugs.

Quantitative Analysis of the Drivers of the Spatio-temporal Evolution of Vegetation NPP in the Beijing-Tianjin-Hebei Ecological Barrier Area

The Taihangshan-Yanshan Region is an important ecological barrier area in Beijing-Tianjin-Hebei, and it is of great importance to investigate the spatial distribution pattern and driving mechanism of net primary productivity （NPP） of vegetation for ecological restoration. The MOD17A3HGF.061 NPP dataset was obtained using the Google earth engine（GEE）, and Sen trend, coefficient of variation, partial correlation, complex correlation, and residual analysis were applied to investigate the spatial and temporal patterns of vegetation NPP in the study area and to quantitatively isolate the relative contributions of climate change and human activities. The results showed that： ① The vegetation NPP in the study area showed an overall increasing trend from 2003 to 2021, with a rate of（C-based）2.57 g·（m2·a）-1 and the distribution characteristics of "low in the surroundings and high in the middle" in the Taihangshan area, "high in the north and low in the south" in the Yanshan area, and "low in the north and low in the south" in the Yanshan area. At the same time, the spatial distribution characteristics of "low around and high in the middle" in the Taihangshan area and "high in the north and low in the south" in the Yanshan area were shown. Nearly 70% of the regions had medium or low volatility of vegetation NPP, and 80% of the regions had the opposite trend of future changes. ② The vast majority of NPP changes were positively correlated with precipitation and negatively correlated with temperature, but the significance was not strong； only 23% of the area had a strong correlation between vegetation NPP changes and meteorological factors, and it was concentrated in the central Yanshan Mountains, while the rest of the area was mainly driven by reasons other than climatic factors. ③ Potentially improved （NPPH>0） and potentially degraded （NPPH<0） areas were roughly equally distributed, but human activities played a positive role in most of the areas （79%）； 76% of the areas were dominated by human activities in the actual improved areas and 58% in the actual degraded areas, and human activities were the main factor dominating the NPP succession of vegetation in the study area. The results of this study provide an important reference for the formulation of precise vegetation ecological protection and restoration policies in the Beijing-Tianjin-Hebei ecological barrier area.

Microscopic investigation of chemical and physical alteration behaviors in sandstone minerals induced by CO2-H2O-rock interactions during CO2 saline aquifer storage.

CO2 saline aquifer storage represents a promising strategy for mitigating the environmental impact of greenhouse gas emissions. However, the long-term effects of CO2 dissolved in formation water on rock minerals remain insufficiently understood. This study utilizes cast thin section analysis, scanning electron microscopy, and energy dispersive spectrometry techniques to perform a comprehensive microscopic investigation on this issue. Experimental results from sandstone core samples drilled from the Ordos pilot field reveal that feldspar minerals predominantly undergo geochemical dissolution, while quartz and clay minerals primarily exhibit physical alterations. Feldspar minerals, including albite, potassium feldspar, and anorthite, exhibit significant geochemical dissolution, characterized by cleavage plane dissolution, swelling, selective dissolution, and in-situ accumulation of dissolution products. This process leads to the formation of secondary minerals such as quartz, kaolinite, and illite, along with various microscopic structures like vugs, pits, and filamentous remnants. Alterations in quartz include the formation of stress-induced microfractures, the attachment of mineral clasts, the precipitation of geochemical reaction products, and pore blockage. In clay minerals, the formation, closure, interconnection, and reconfiguration of microfractures are evident characteristics, particularly at the nanoscale. The products of CO2-H2O-rock interactions typically comprise a complex mixture of physical and chemical products, marked by intricate elemental compositions and diverse structural forms, including blocky, granular, powdery, filamentous, and floc-like structures. This work reveals the distinctive chemical dissolution mechanisms of sandstone with complex mineral compositions, clarifies the CO2-induced physical alteration behavior of multiple minerals and identifies the multi-scale migration mechanisms of products generated by CO2-H2O-rock interactions. Moreover, these interactions have a dual impact: they enhance the porosity and permeability, while also potentially compromising the structural integrity of the rock and formation. This research provides a foundation for assessing the impact of CO2 storage on fluid flow and evaluating environmental safety concerns, such as CO2 leakage and geological subsidence.

Study on the Formation and Management Mechanism of New Productivity in Regional Economy from the Perspective of Modern Chinese History: Transformation from Traditional Agriculture to Modern Industry

This study explores the formation of new-quality productive forces and the management mechanisms underlying the transformation of regional economies from traditional agriculture to modern industry within the framework of China's modern history. During the transformative period of the late Qing Dynasty and the Republic of China, regional economic development underwent significant shifts driven by industrialization, technological innovation, and evolving governance models. The study aims to identify the factors influencing the emergence of new-quality productive forces and their management, focusing on the interplay between historical context and economic transitions. Employing a combination of historical analysis, comparative regional studies, and data interpretation, this research reveals that the formation of new-quality productive forces was shaped by diverse regional conditions, including infrastructure, policy interventions, and market dynamics. The findings highlight the critical role of adaptive management mechanisms in optimizing economic transformation and achieving sustainable development. This research contributes to the understanding of historical economic transitions and offers valuable insights for policymakers and researchers in addressing current regional development challenges. It underscores the importance of context-specific approaches in fostering economic modernization and enhancing regional competitiveness.

Analyzing the Spatial Patterns and Impact Factors of Vegetation Net Primary Productivity and Precipitation Utilization Efficiency in Heilongjiang Province Under Climate Change

Understanding the spatial patterns and driving mechanisms of net primary productivity (NPP) and precipitation utilization efficiency (PUE) is crucial for assessing ecosystem services. This study analyzed the variations in NPP and PUE in Heilongjiang Province from 2001 to 2020, using MOD17A3 NPP products and meteorological, topographic, and land use data. The distribution of the NPP and PUE of seven land use categories was determined in the study, namely, cropland, forest, grassland, water, barren, impervious and wetland. The multi-year spatial averages for NPP and PUE were 428.96 gC·m−2·a−1 and 0.74 gC·m−2·mm−1, respectively, with forests showing the highest values and barren lands the lowest. During the study period, 91.4% of the NPP increased at an average rate of 3.36 gC·m−2·a−1, while PUE exhibited a polarized trend. Changes in land use, especially conversions involving cropland and forest, along with climatic factors such as rising precipitation and temperature, significantly influenced NPP and PUE dynamics. These findings provide a scientific basis for ecological restoration and the assessment of ecosystem function under changing climatic conditions.

On willingness to pay and impact mechanism of green agricultural products: a case of shrimp rice in Hunan, China

The burgeoning interest in green agriculture represents a pivotal shift towards environmentally friendly farming systems but sales of its products have been poor. Therefore, guiding consumers to pay reasonably can help green agricultural enterprises formulate appropriate marketing strategies and enhance public health and environmental quality. This paper takes shrimp rice (SR) as an example, based on 1,158 consumers in the largest rice province Hunan, and seeks to detect which factors affect the public’s willingness to pay (WTP) by adopting the Contingent Valuation Method (CVM) and Heckman two-step Model. After removing biased observations, the results show that most respondents recognize the value of SR, whose premium is 1.47 yuan/kg, with a 25.85% premium rate. Moreover, positive external cognitions (psychology, environment, safety, policy) can moderate consumers’ WTP to varying degrees by strengthening their corresponding motivations. In addition, older, highly educated men who are familiar with SR and high-income but small-scale households with children and the elderly are more likely to pay a higher premium. Hence, some recommendations are put forward to enhance consumers’ external cognitions, providing an indispensable scientific basis for developing countries to promote the sustainable development of environmentally friendly agriculture.

Synergistic Matching and Influencing Factors of Grain Production and Cropland Net Primary Productivity in the Black Soil Region of Northeast China

Exploring the spatiotemporal dynamics, spatial mismatch, and complex influencing mechanism of grain production and cropland productivity in the black soil region of northeast China (BSRNC) is essential for the synergistic protection and utilization of black soil cropland and sustainable grain production. The BSRNC has realized cropland expansion and grain production increases in the past decades. This implied a substantial investment has been made in the region’s agriculture. However, at present, knowledge on the spatial mismatch and influencing factors of grain production and cropland productivity is still unclear. This study analyzed the spatial–temporal mismatch characteristics of grain production and cropland net primary productivity (CNPP) using the gravity center model, spatial autocorrelation analysis, and spatial mismatch index (SMI), and identified the spatial heterogeneity and prediction–response relationships of influencing factors based on a geographically and temporally weighted regression (GTWR) model and boosted regression tree (BRT) machine learning algorithm. The findings indicated that grain production and CNPP have been increasing, but the overall spatial pattern of cold hotspots has not changed obviously in the BSRNC from 2000 to 2020. The SMI has shown a decreasing trend, indicating that the synergistic development of grain production and CNPP has been obvious, which plays an important role in sustainable food supply capacity. Agricultural production and the natural environment have always been critical factors influencing the spatial mismatch. Specifically, the marginal impact of fertilizer application has undergone a shift. This study may provide new clues for the formulation of regional strategies for sustainable food supply and black soil cropland system protection.

Molecular Simulation Study on the Adsorption Mechanisms of Microbial Components and Metabolic Products on Activated Carbon in HVAC Systems

Molecular Simulation Study on the Adsorption Mechanisms of Microbial Components and Metabolic Products on Activated Carbon in HVAC Systems

Natural products that alleviate depression: The putative role of autophagy.

Major depressive disorder (MDD) is a common mental disorder that severely disrupts psychosocial function and decreases the quality of life. Although the pathophysiological mechanism underlying MDD is complex and remains unclear, emerging evidence suggests that autophagy dysfunction plays a role in MDD occurrence and progression. Natural products serve as a major source of drug discovery and exert tremendous potential in developing antidepressants. Recently published reports are paying more attention on the autophagy regulatory effect of antidepressant natural products. In this review, we comprehensively discuss the abnormal changes occurred in multiple autophagy stages in MDD patients, and animal and cell models of depression. Importantly, we emphasize the regulatory mechanism of antidepressant natural products on disturbed autophagy, including monomeric compounds, bioactive components, crude extracts, and traditional Chinese medicine formulae. Our comprehensive review suggests that enhancing autophagy might be a novel approach for MDD treatment, and natural products restore autophagy homeostasis to facilitate the renovation of mitochondria, impede neuroinflammation, and enhance neuroplasticity, thereby alleviating depression.

Achieving ultra-stable Li-CO2 battery via synergistic effect of RuxIr1-xO2 bimetallic oxide catalyst

Rechargeable Li-CO2 batteries have attracted worldwide attention in recent years since it can realize the eco-friendly utilization of greenhouse gas CO2 and offer high theoretical energy density. However, the current Li-CO2 battery still has the shortcomings of a high charging platform and poor cycling performance. Herein, the mixed ultrafine Ru/Ir oxide nanoparticles are uniformly loaded on carbon nanotubes (RuxIr1-xO2/CNTs) as an efficient air cathode for Li-CO2 battery by a simple one-step hydrothermal method. The Li-CO2 battery with RuxIr1-xO2/CNTs cathode performed the discharge specific capacity of 3956.7 mAh g−1, ultralong cycling stability (>6000 h), low charge platform and over-potential (3.85 V/1.22 V). The excellent electrochemical performance is attributed to the synergistic effect of RuxIr1-xO2 bimetallic oxide, enhancing the cycling stability and affecting the formation/ decomposition mechanism of the discharge product. This work provides an in-depth perspective on the catalyst effect and identifies a feasible way to construct an ultra-stable Li-CO2 battery.

The Impact of High-Tech Policies on Corporate ESG Performance: Evidence from China

In light of resource and environmental constraints, the economic growth model is undergoing significant transformations. New quality productivity is the latest high-tech policy in China’s current development. Comprehensively improving the new quality productivity level of enterprises is the core driving force behind promoting productivity progress and sustainable development. The objective of this study was to employ machine learning techniques to comprehensively assess the level of new quality productivity exhibited by enterprises and to identify the spatiotemporal evolution characteristics thereof. Additionally, the study sought to investigate the impact and the specific mechanism of new quality productivity on the ESG performance of enterprises from a micro perspective. The study revealed that new quality productivity has a considerable impact on the ESG performance of enterprises, particularly in cases where the enterprise has a long history and is engaged in significant pollution. The underlying mechanism is that new quality productivity can enhance an enterprise’s ESG performance by alleviating financing constraints and improving the efficiency of employee innovation. Additionally, further research indicated that new quality productivity primarily influences the environmental and social ratings of enterprises.

(Invited) First-Principles Modeling of Degradation Mechanisms of the NaO2 Discharge Product in Na-O2 Battery Cells

The current climate crisis necessitates the development of improved electrochemical storage devices, such as aprotic alkali metal-O2 batteries (Li/Na-O2), which have greater than threefold higher thermodynamic gravimetric energy densities than Li-ion batteries. With a greater elemental abundance of sodium and low observed overpotential losses, Na-O2 batteries have become a focus of research interest. However, despite recent efforts, poor cell stability continues to plague Na-O2 cells, inhibiting commercial viability. A contributing factor to the poor cell stability is a degradation of the desired NaO2 discharge product at the cathode, resulting from undesirable interactions with the organic cell electrolyte under periods of cell idling where there is no charge transfer between the two electrodes. These undesirable interactions are hypothesized to degrade the NaO2 discharge product through two main pathways: (i) chemical transformation to hydrated sodium-oxygen species resulting from a chemical reaction with the electrolyte molecules and (ii) deleterious dissolution into the electrolyte. Thus far, practical solutions to improve stability have remained elusive, but elucidating molecular-level mechanistic details of these deleterious processes, using combined theory-driven and experimental approaches, could accelerate the discovery of practical design changes to overcome these stability bottlenecks.The goal of the present work is to couple computational and experimental studies to elucidate key molecular-level mechanistic insights of the undesirable interactions between the cell electrolyte and the surface of the NaO2 discharge product. We utilize periodic Density Functional Theory (DFT) calculations and ab initio molecular dynamics (AIMD) simulations to probe the two main NaO2 discharge product degradation mechanisms. To model the surface of the NaO2 discharge product, which in the case of high donor number electrolytes is deposited in a cubic confirmation, the cube faces and edges are represented as terrace and step facets, respectively, to capture the fact the undercoordinated cube edges could exhibit a different surface chemistry than the relatively pristine cube faces. At these two surface terminations, we elucidate the energetics that govern the degradation mechanisms of the NaO2 discharge product under cell idling conditions, as described below.To probe the chemical transformation of the NaO2 discharge product towards hydrated sodium-oxygen products, we elucidate the energetics of hydrogen abstractions from the electrolyte molecules to the NaO2 surface. With regards to the hydrogen coverage on the NaO2 surface, we find that there exists a plateau in the abstraction thermodynamics for the uptake of hydrogen, and at high coverages, the terrace NaO2 surface undergoes a series of favorable surface reconstructions towards sodium hydroxide species. Interestingly, we find that the free energy of activation for hydrogen abstraction from the electrolyte is not strongly influenced by the surface termination (terrace vs. step), as one would typically expect based on coordination number arguments. For the study of the deleterious dissolution of the NaO2 discharge product, we elucidate the energetics of elementary material loss mechanisms from the surface. We find that it is thermodynamically favorable for the surface to dissolute as individual NaO2 units, maintaining the NaO2 stoichiometry of the surface, with the thermodynamic surface penalty to undergo dissolution for the step facet being approximately ½ of the penalty for the pristine terrace facet. Further, we find the free energy of activation for dissolution of the step facet to be approximately ½ of the energy barrier of the terrace facet, suggesting that, unlike in the hydrogen abstraction process, the NaO2 cube edges drive the undesirable dissolution during idling. In closing, we comment how the current work lays the groundwork for future combined computational-experimental studies and how they may be used to propose practical design changes.

Transcriptome sequencing and SSR prediction of Clematis calyx based on SMRT sequencing platform

Clematis is an excellent vertical greening plant for garden viewing vines, with great ornamental and high medicinal value. To obtain transcriptome information and functional gene data for the Clematis calyx, this study utilized three biological replicates of the calyx from each of the three Clematis varieties: ‘Henryi’, ‘Polish spirit’, and ‘Mme Julia Correvon’ Single-molecule real-time sequencing technology was employed for full-length transcriptome sequencing. The study revealed that 21,673,173 non-chimeric sequences were identified through full-length transcriptome sequencing. After clustering, correction, and redundancy removal, 40,465 high-quality, full-length transcripts were obtained. Among these transcripts, there were 15,488 long non-coding RNA (lncRNA), 9,212 simple sequence repeats (SSR) sites, 1,247 transcription factors (TFs), 1,228 alternative splicing events, and 7,189 selectively polyadenylation sites predicted. In addition, 7,442 primer pairs were designed based on the SSR sites, covering 80.76% of the total SSR. 15 primer pairs were randomly selected for amplification, and 73.3% of them were successfully amplified. Transcript annotation results showed that 38,439, 38,094, 26,815, and 33,407 transcripts were annotated to the Nr, KEGG, KOG, and SwissProt databases, respectively. Among these, the KEGG database identified 137 metabolic pathways, including biosynthesis of secondary metabolites, carbon metabolism, and amino acid biosynthesis. 104 and 7 transcripts are involved in the flavonoid and anthocyanin metabolism pathways, respectively. The above results provide initial insights into the transcriptome information and functional characteristics of Clematis calyx. This critical data supports future research on marker primers for the color mechanism of Clematis calyx, the pathways and regulatory mechanisms of flavonoids and other products, as well as specific trait genes.

Experimental and numerical investigation on pyrolysis and combustion behavior of biomass bast fibers: Hemp, flax and ramie fibers

As an important renewable biomass material, bast fiber of crops has various application values. However, its flammable and decomposable characteristics bring challenges to its storage and practical applications. In this work, a steady-state tube furnace (SSTF) was built independently. And the pyrolysis and combustion behavior of three typical bast fibers: hemp, flax, and ramie were systematically studied. Among them, the total heat release of hemp and ramie was about 49.4 % higher than that of flax. And the average CO content of flax and ramie were 35.2 % and 39.5 % lower than hemp, respectively. Data-based fire hazard assessment illustrated that the hemp had the highest fire hazard. A Genetic Algorithm (GA)-based four-step reaction model was proposed and accurately predicted the pyrolysis process of bast fibers (Fdev≤0.016). Furthermore, the pyrolysis products of bast fibers were studied based on TG-FTIR and PY-GC-MS. On this basis, the possible production mechanism of pyrolysis products was proposed. This work will provide a reference for research on pyrolysis and combustion of biomass.

Research on the Value Creation Mechanism of Green-Driven Products in the Internet+ Era

In order to improve the value of green-driven products, this paper studies the value creation mechanism of green-driven products in the Internet+ era. Under the framework of the classic Cournot output game, based on the bounded rationality assumption of the participants, this paper constructs a novel Cournot duopoly investment game model, and analyzes the dynamic adjustment mechanism of the participants' investment. The decision variable of participating enterprises is to select the optimal investment amount, and each production enterprise makes investment decisions in the next period according to the observed marginal profit of the current period to maximize the profit. Through calculation and analysis, it can be known that three boundary equilibriums and one interior point equilibrium of the discrete dynamic model system are obtained in this paper. The experimental analysis shows that the value creation mechanism of green-driven products proposed in this paper can effectively promote the value of green-driven products.

Mediating role of trust and privacy concerns between web assurance mechanism and purchase intention of online products

Trust and privacy concerns are the rudimentary pillars of all the crucial online transactions. Web assurance mechanisms such as secure payment gateways, trust seals, and data protection measures, are designed to build credibility between consumers and online businesses. This research study attempts to examine the mediating role of trust and privacy concerns between web assurance mechanisms and purchase intention of online products. This will provide valuable insights to the underlying psychological processes and factors that influence consumer behavior in the online shopping context. A conceptual model has been framed to investigate the direct and indirect relationship between web assurance mechanism and purchase intention of online products via trust and privacy concern. This study uses data collected from 342 respondents. Smart PLS4 was used for the assessment of measurement model and structural model. The research findings claims that the web assurance mechanism has a significant impact on purchase intentions, privacy concerns, and trust. It was also found that when privacy concerns and trust were introduced as mediators, the indirect effect was still significant, which indicates that privacy concerns and trust partially mediate the direct relationships. The findings of the study can help identify the specific factors that contribute to consumer comprehension and assess how web assurance mechanisms influence these concerns. The findings can inform the development of privacy-enhancing measures and policies to alleviate consumer worries and increase purchase intention.

Spatial–Temporal Patterns and the Driving Mechanism for the Gross Ecosystem Product of Wetlands in the Middle Reaches of the Yellow River

Wetlands are crucial for sustainable development, and the evaluation of their GEP is a key focus for governments and scientists. This study created a dynamic accounting model for wetland GEP and assessed the GEP of 39 wetlands in the middle reaches of the Yellow River in Ningxia province. The results indicate that Ningxia province’s wetlands have an average annual GEP of CNY 5.24 billion. Haba wetland contributes the most at 0.52, while Qingtongxia, Sha, and Tenggeli wetlands follow with 0.12, 0.04, and 0.03, respectively. Climate regulation is the most valuable function at 38.24%, with species conservation and scientific research/tourism at 24.93% and 15.11%, respectively. Ningxia’s northern wetlands are vast and shaped by the Yellow River, while the smaller, seasonal southern wetlands are more affected by rainfall and mountain groundwater. Southern wetlands show a strong correlation between GEP and precipitation (0.82), whereas northern wetlands have a moderate correlation between GEP and evapotranspiration (0.52). The effective conservation and management of these wetlands require consideration of their locations and weather patterns, along with customized strategies. To maintain the stability of wetland habitats and provide a suitable environment for various species, it is essential to preserve wetlands within a certain size range. Our study found a strong correlation of 0.85 between the wetland area and the GEP value, indicating that the size of wetlands is a key factor in conserving their GEP. The results provide accurate insights for creating a wetland ecological benefit compensation mechanism.

Structural characterization of degradation products of phenol red used as zero permeability marker in in-situ rat intestinal permeability studies by LCMS-IT-TOF

In this study, the quantitative determination of phenol red with using HPLC, the permeability marker widely used in gastrointestinal studies, and its stability in various apolar phase solvents were investigated. In addition, the mechanisms of degradation products obtained were tried to be elucidated by using the LCMS-IT-TOF device. The proposed HPLC method utilizes a Perkin Elmer C18, 5 μm, 250 mm × 4.6 mm i.d. column, a mobile phase consisting of phosphate buffer and methanol in the proportion of 50:50 (v/v) with apparent pH adjusted to 3.2 and detected at 430 nm using a photodiode array detector. The method exhibits linearity within the concentration range of 5–200 µg/mL, with a calculated R2 of 0.9981. In situ conditions, the recovery is in the range of 89.8–103.6 %. Furthermore, high-resolution mass studies were identified three degradation products that occur when phenol red was dissolved either ethanol or methanol medium. The method has a low cost of consumables and is very easy to apply to the procedure and analyze degradation products while easily applied to phenol red analysis in various mediums. High-resolution mass screening analysis confirmed the proposed structure of the degradation product. The validation and robustness studies were fulfilled to display the performance of the method in various analytical environments. The greenness and blueness evaluations of the developed method were also made in detail. The AGREE score of the method was calculated as 0.64, AGREEprep 0.68, MoGAPI 0.78, and BAGI scale score as 65.0. In short, the method is perfectly green, applicable, and practical. Finally, phenol red concentrations analyzed in samples obtained in in-situ animal studies were conducted to demonstrate the applicability of the developed method.

Research progress of natural products targeting tumor-associated macrophages in antitumor immunity: A review.

As an important innate immune cell in the body, macrophages have a strong ability to phagocytic tumor cells and maintain the innate immune response. Tumor-associated macrophages play a more prominent role in regulating tumor immunity and are currently an important target of antitumor immunity. As a new type of antitumor therapy, tumor immunotherapy has great potential, combined chemotherapy, targeting and other therapeutic means can significantly enhance the antitumor therapy effect. At present, a number of natural products have been proved to have significant immunomodulatory and antitumor effects, and have become a hot field of antitumor immunity research. Studies have found that a variety of natural products, such as polysaccharides, flavonoids, saponins, lactones, and alkaloids, can induce the polarization of M1 macrophages, inhibit the polarization of M2 macrophages, and regulate the expression of immune-related cytokines by targeting specific signaling pathways to enhance the killing effect of macrophages on tumor cells and improve the tumor immune microenvironment, and finally better play the antitumor immune function. In this paper, by summarizing the research results of the specific mechanism of natural products targeting tumor-associated macrophages to exert antitumor immunity in recent years, we discussed the aspects of natural products targeting tumor-associated macrophages to enhance antitumor immunity, in order to provide a new research idea for tumor immunotherapy and further improve the effectiveness of clinical antitumor therapy.