Solid Phase Research Articles

Determination of five veterinary drug residues in milk by ultra-high performance liquid chromatography-quadrupole/electrostatic field orbitrap mass spectrometry based on modified chitosan membrane purification

Milk is an important consumer product with high nutritional value. The presence of veterinary drug residues in milk owing to the indiscriminate use of veterinary drugs may affect consumer health. In the mass spectrometric analysis of trace compounds, chromatographic co-eluting components easily interfere with the mass spectral signals obtained, affecting the accuracy of qualitative and quantitative analyses. Matrix purification is a promising method to reduce the matrix effect. Chitosan is a natural biopolymer with numerous active functional groups such as amino, acetyl, and hydroxyl groups; these groups can adsorb lipids through hydrophobic and electrostatic interactions. Chitosan also has the advantages of low production cost, stable chemical properties, and convenient modification. Novel chitosan-based materials are promising candidates for lipid purification. In this study, a chitosan membrane was modified with trimethoxyoctadecylsilane (C18-CSM). C18-CSM was prepared through one-step hydrolysis and used as a dispersive solid phase extraction (DSPE) adsorbent to purify the matrix during milk pretreatment. We combined C18-CSM with ultra-high performance liquid chromatography-quadrupole/electrostatic field orbitrap mass spectrometry (UHPLC-Q/Exactive Orbitrap MS) to develop an effective method for the extraction and determination of ofloxacin, enrofloxacin, ciprofloxacin, diazepam, and metronidazole in milk. C18-CSM was characterized using scanning electron microscopy, Fourier transform infrared spectroscopy, and water contact angle testing. The results indicated that the material has a rough surface and uniformly dense cross-section. The water contact angle of C18-CSM was 104°, indicating its good hydrophobicity. The pretreatment conditions (extraction solvent, dosage of NaCl, extraction frequency, and dosage of C18-CSM) that influenced the recoveries of the five veterinary drugs were investigated in detail. The optimal conditions were established as follows: 5% formic acid in acetonitrile, 1 g NaCl, extraction 1 time, 20 mg C18-CSM. Separation was performed on a Hypersil GOLD VANQUISH column (100 mm×2.1 mm, 1.9 μm). The mobile phase consisted of 0.1% formic acid aqueous solution and 0.1% formic acid in acetonitrile, and was flowed at a rate of 0.3 mL/min. The sample injection volume was 1 μL, and the column temperature was maintained at 25 ℃. Mass spectrometric analysis was performed in positive electrospray ionization mode. To verify the necessity of the purification material, the matrix effect was investigated using the matrix-matched standard curve method. The use of C18-CSM reduced the matrix effects of the five necessity drugs from the range of -22%-8.8% to the range of -13%-3.6%, indicating that C18-CSM is a highly efficient DSPE material. Under optimal conditions, the developed method showed good linearities within the range of 0.5-100 μg/L, with correlation coefficients (r2)≥0.9970. The limits of detection(LODs) and quantification (LOQs) were 0.2 μg/L and 0.5 μg/L, respectively. To assess the accuracy and precision of the method, we prepared milk samples with three spiked levels (low, medium, and high). The recoveries of the five veterinary drugs were ranged from 79.5% to 115%, and the intra-day and inter-day relative standard deviations were 7.0%-13% (n=6) and 1.3%-11% (n=3), respectively. This study provides a simple, accurate, and reliable method for the rapid and simultaneous determination of the five veterinary drug residues in milk.

Preserving the Aromatic Profile of Aged Toma Piemontese PDO Cheese with Gaseous Ozone Technology: A Quality Assessment via SPME-GC–MS/E-Nose

The efficacy of low gaseous ozone concentrations (300 ppb and 400 ppb) in controlling spoilage microflora and preserving the quality of the aged Toma Piemontese PDO cheese was explored. The research integrates consumer tests, Gas Chromatography-Mass Spectrometry (GC-MS) with Solid phase Microextraction (SPME) fiber and Electronic Nose (e-nose) analysis to conduct a detailed assessment of the cheese's aromatic composition. Results indicate that low ozone concentrations significantly affected spoilage microflora, preserving the overall quality. Through GC-FID (Flame Ionization Detection) analysis, 22 of all identified compounds by GC-MS were quantified, including ethyl acetate (sweety), diacetyl and acetoin (buttery). Compared with the untreated sample, ozone treatments maintained the distinctive characteristics of Toma Piemontese PDO cheese, reducing the formation of off-flavors-related compounds (i.e., ethanol). Moreover, ozone-treated samples correlated with positive aroma scores given by consumers. However, sensory perception involves complex interactions among aroma compounds, highlighting the importance of advanced approaches. The utilization of a 12-sensor Quartz Microbalance (QMB) e-nose played a crucial role in identifying subtle differences in aroma, contributing to a more nuanced understanding of ozone treatments on the cheese's sensory profile. In conclusion, this research demonstrates the potential of ozone technology as a viable and effective method for improving the quality of aged Toma Piemontese PDO cheese.

Reconstruction and Generation of Porous Metamaterial Units via Variational Graph Autoencoder and Large Language Model

Abstract In this paper, we propose and compare two novel deep generative model-based approaches for the design representation, reconstruction, and generation of porous metamaterials characterized by complex and fully connected solid and pore networks. A highly diverse porous metamaterial database is curated, with each sample represented by solid and pore phase graphs and a voxel image. All metamaterial samples adhere to the requirement of complete connectivity in both pore and solid phases. The first approach employs a Dual Decoder Variational Graph Autoencoder to generate both solid phase and pore phase graphs. The second approach employs a Variational Graph Autoencoder for reconstructing/generating the nodes in the solid phase and pore phase graphs and a Transformer-based Large Language Model (LLM) for reconstructing/generating the connections, i.e., the edges among the nodes. A comparative study is conducted, and we found that both approaches achieved high accuracy in reconstructing node features, while the LLM exhibited superior performance in reconstructing edge features. Reconstruction accuracy is also validated by voxel-to-voxel comparison between the reconstructions and the original images in the test set. Additionally, discussions on the advantages and limitations of using LLMs in metamaterial design generation, along with the rationale behind their utilization, are provided.

Fluorescent Nanowires from Dual‐State Emitting Fluorophores Directed by Molecular Motors and Aggregation‐Induced Emission: Produce Quantized Light Spectrum

AbstractLuminescent materials require systems that exhibit both dual‐state emission (DSE) and aggregation‐induced emission (AIE) to overcome the limitation of aggregation‐caused quenching (ACQ). Herein, a molecular assembler capable of crafting nanowires that exhibit programmable fluorescence across a broad spectrum of colors in a precisely quantized manner is reported. Because it is a starburst dendritic box made of PAMAM dendrimer (P), controller (C) molecules, and motor (M) molecules, the assembler is called PCM. Here, Nile red is chosen as C and placed into the hollow core of the dendrimer; a double ratchet motor (DRM) is chosen as M and is connected to the N‐terminals of the PAMAM dendrimer. While aqueous dispersed PCM assemblers have broad fluorescence bands beyond 300 nm, their crafted nanowires produce quantized cyan‐green, yellow, and orange‐red light emission in the spectra. These PCM assemblers are shown to hold long‐term memory, rapid switching, and energy harvesting by modulating photonic bandgaps, causing a longer redshift in the solid phase. The DSE of PCM can yield versatile photonics applications like bioimaging and energy harvesting. As PCM nanowires can modulate photonic bandgaps to cause a longer redshift, PCM fluorophores hold promise for drug delivery and cell separation like infrared‐sensitive operations.

A man for all times To the 100th anniversary of the birth of academician N.S. Enikolopov

In 2024, the 100th anniversary of the birth of the outstanding physical chemist of the XX century, Academician N.S. Enikolopov, is celebrated. The scientist had a great thirst and love for science, was a talented researcher, organizer and teacher. Its scientific school has nurtured many scientists. It is difficult to overestimate his contribution to the development of chemical science and the polymer industry. Among the most notable achievements of Nikolai Sergeevich are the detection and investigation of abnormally fast polymerization in the solid phase, the discovery of the interchain exchange reaction in the formation of heterochain polymers, etc.

Sulfidation−reoxidation enhances heavy metal immobilization by vivianite

Iron minerals in nature are pivotal hosts for heavy metals, significantly influencing their geochemical cycling and eventual fate. It is generally accepted that, vivianite, a prevalent iron phosphate mineral in aquatic and terrestrial environments, exhibits a limited capacity for adsorbing cationic heavy metals. However, our study unveils a remarkable phenomenon that the synergistic interaction between sulfide (S2−) and vivianite triggers an unexpected sulfidation−reoxidation process, enhancing the immobilization of heavy metals such as cadmium (Cd), copper (Cu), and zinc (Zn). For instance, the combination of vivianite and S2− boosted the removal of Cd2+ from the aqueous phase under anaerobic conditions, and ensured the retention of Cd stabilized in the solid phase when shifted to aerobic conditions. It is intriguing to note that no discrete FeS formation was detected in the sulfidation phase, and the primary crystal structure of vivianite largely retained its integrity throughout the whole process. Detailed molecular-level investigations indicate that sulfidation predominantly targets the Fe(II) sites at the corners of the PO4 tetrahedron in vivianite. With the transition to aerobic conditions, the exothermic oxidation of CdS and the S sites in vivianite initiates, rendering it thermodynamically favorable for Cd to form multidentate coordination structures, predominantly through the Cd-O-P and Cd-O-Fe bonds. This mechanism elucidates how Cd is incorporated into the vivianite structure, highlighting a novel pathway for heavy metal immobilization via the sulfidation−reoxidation dynamics in iron phosphate minerals.

A finite volume formulation for one-dimensional Stefan problems

This paper presents a numerical formulation that combines the finite-volume method with a time-dependent boundary-fitted coordinate system to tackle the moving boundary problems for the one-dimensional (1-D) heat equation. Following the formulation process, an algorithm was created with the help of the linear algebra package Eigen to generate the data for the numerical solution. Four benchmark cases of heat conduction were investigated by this approach and compared to the analytical solution: a fixed boundary case, the liquid phase of a melting process, the solid phase of a melting process, and an ablating process. The results demonstrate the capability of the presented numerical formulation in efficiently solving the general 1-D heat problems, especially the one-phase Stefan problems, as well as the consistency of the numerical and analytical solutions. Future works can strive to extend the formulations to Stefan problems of two phases or higher dimensions. The work can then be extended to real-life applications, such as the spacecraft re-entry ablation process, and the process of iceberg melting, demonstrating its critical value in solving practical problems.

К вопросу оценки качества сырья из каспийской атерины (Atherina boyeri caspia (Risso, 1810))

The purpose of this work was to establish the informative value of methods of structural analysis of biological fluids in determining the prospects of using atherina (Atherina boyeri caspia (Risso, 1810)) as a source of dietary protein in aquaculture. For the first time, solid-phase structures of atherina muscle homogenates were studied. It is known that the solid phase of biological fluids formed under conditions of wedge-shaped dehydration is a visualization of biochemical processes occurring in an organism or organ. The study of the morphological picture of a dried drop (facies) makes it possible to establish associative links between the features of the structuring of the studied liquid and its composition, as well as to determine the nature of the impact of environmental factors on a living system. The results of the study made it possible to establish the main type of homogenate facies and its morphological parameters, which indicate the consistency of biochemical processes and the presence of high-grade protein in the muscle tissue of the Caspian atherina, caught both in the spring and autumn seasons. The size and weight parameters of fish, the content of water-soluble protein in muscle tissue are characterized. For the first time, a comparative analysis of the level of water-soluble protein and solid-phase structures of muscle homogenates of Caspian atherina caught in different seasons in the coastal waters of Dagestan was carried out. Atherina is a food component for many fish living in the Caspian Sea. It was determined that in October, the content of muscle water-soluble protein in atherina tended to increase relative to March. During the feeding period, the accumulated part of the protein components turns into lipid components, which accumulate intensively, therefore, there are no significant seasonal differences in the content of water-soluble protein. It has been established that the biochemical processes occurring in muscle tissues are reflected in the solid-phase structures of biological fluids formed under conditions of wedge-shaped dehydration. The obtained results of the trend towards an increase in water-soluble muscle proteins in the body and an increase in the population in recent years indicate the importance of the use of Caspian atherina in the quality of live feed at fish farms.

Synthesis of plyphenol-containing cationic linear and dendrimeric peptides with anti-oxidant activity

Natural polyphenols are of great interest from the point of view of their use for the pharmacological control of oxidative stress and many diseases. However, the low bioavailability and rapid metabolism of polyphenols in the form of glycosides or aglycones stimulates the search for effective means of delivery into systemic circulation. Conjugation of polyphenols with cationic amphiphilic peptides can result in compounds with strong antioxidant activity and the ability to cross biological barriers. Such compounds may be in demand as drugs for antioxidant therapy, including for the treatment of viral, oncological and neurodegenerative diseases due to the diverse range of biological activities inherent in polyphenols and peptides. In this work, cationic linear and dendrimer amphiphilic cationic peptides were synthesized by the solid phase method, and a number of peptides were conjugated to gallic acid (Ga). Ga is a non-toxic natural phenolic acid and an important functional element of many flavonoids with high antioxidant activity. It was shown that the resulting Ga-peptide conjugates exhibited antioxidant (antiradical) activity that was 2-3 times higher than that of ascorbic acid. Other tests indicated that the addition of Ga did not affect the toxicity and hemolytic activity of the conjugates. Ga-modified peptides stimulated the transmembrane transfer of the pGL3 plasmid encoding the luciferase reporter gene; however, the addition of Ga to the N-terminus of the peptide reduced its transfection activity. Some of the resulting compounds had noticeable inhibitory activity against theE. сoli-Dh5α strain.

Parameter sensitivity of a wood chips flow model

AbstractA computational fluid dynamics (CFD) study of the parameter sensitivity of a wood chips model was performed on an industrial impregnation vessel, which is the first step in a continuous cooking system. The solid and liquid phases were both treated as continua and it was found that the continuum model for the solid wood chips phase could capture the previously observed oscillating formation of arches in the contracting part of the vessel, which will occur at different levels of volume fraction depending on the material constants. The parameters that were examined are the solid pressure, permeability, viscosity, and wall friction. It was found that all the parameters strongly affect the distribution of the wood chips in the vessel as well as the oscillation effects, hence also the flow field which is important to accurately predict in order to ensure optimal performance of the impregnation vessel. Thus, correct material data for these types of simulations are crucial to the outcome and should be chosen for the appropriate situation and bio‐material.

Development of a Molecularly Imprinted Polymer for Determination of Atenolol Based on Selective Solid Phase Extraction and Application in Pharmaceutical Samples

This paper demonstrates the synthesis and storage of molecular-imprinted polymers (MIP) at room temperature using bulk polymerization of atenolol (Ate), which is characterized by high sensitivity, low costs, and high stability. The research used 0.99:6:20 mmol ratios of template, monomer, and cross-linking agents for the polymerization in order to ensure an appropriate adsorption capacity. By making MIP for atenolol as Ate-MIP, which could be looked at with a UV-VIS spectrophotometer at 276 nm, Fourier- transform infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM), a functional monomer of allyl chloride with cross-linking ethylene glycol dimethyl acrylate was made. Mass spectrometric (MS) detection may use allyl chloride to determine atenolol levels in pharmaceutical preparations. The GC/MS methods developed in this study are accurate, sensitive, and precise and can be easily applied to (NOVATEN/India and ATENOIOI/U.K.) tablets in pharmaceutical preparation. The elution process was applied to the template (Ate) from the Ate-MIP, which developed cavities, caused by using porogenic solutions of methanol, chloroform, and acetic acid (70:20:10, respectively). The maximum adsorption capacity of Ate-MIP was 2.9957 µmol/g, and the ratio of template to monomer was 1:1 in adherence to the Langmuir isotherm model. A solid-phase extraction (SPE) syringe packed with molecular imprinted polymers (MIPs) was used to selectively separate and pre-concentrate Ate from aqueous solutions and estimations of atenolol.

Assessment of Heavy Metal Contamination and Health Risks in “Snow Cover–Soil Cover–Vegetation System” of Urban and Rural Gardens of an Industrial City in Kazakhstan

This article investigates the extent of heavy metal pollution in both urban and rural gardens in Pavlodar, which cultivate potatoes and tomatoes. As a city of industrialization, Pavlodar is exposed to emissions from industrial enterprises, transport and stove heating. The city also has the highest incidence of environmental diseases among the population. This study examines the accumulation of heavy metals and metalloid in the snow, their migration into the soil and their accumulation in plants, and assesses the non-cancer and cancer health risks of consuming these vegetables. The results show that the concentrations of trace elements in the solid phase of snow decrease in the following order: Fe (26,000) > Mn (592.5) > Cr (371.3) > Zn (338.8) > Pb (161.9) > Cu (142.5) > Ni (30.9) > As (15.1) > Co (12.1) > Cd (2.6). In soils, the concentrations of elements decrease in the following order: Mn (22,125) > Fe (20,375) > Zn (246.9) > Cr (109.5) > Cu (39.3) > Pb (25.6) > Ni (22.4) > As (9) > Co (6.6) > Cd (0.2). In urban gardens, the snow pollution coefficient was the highest. In rural gardens, the contamination index varied from 0.3 (Cr) to 5.3 (Cd). Magnesium in the soil exceeds the maximum allowable concentration (MPC) by 28.6–35.7 times, and zinc by 1.6–10.9 times. Only zinc and copper exceed the MPC for vegetables. Nickel in potatoes exceeds MPC by a factor of 6 and in tomatoes by a factor of 4.4. The cobalt content in tomatoes exceeds the background value by 2.2 times, with a maximum value of 5.3 times. The risk assessment showed that the non-carcinogenic and carcinogenic risks associated with potato and tomato consumption were low. However, these risks are higher in urban areas than in rural areas.

Soil Solution Properties of Tropical Soils and Brachiaria Growth as Affected by Humic Acid Concentration

The soil solution is the compartment where plants uptake nutrients and this phase is in equilibrium with the soil solid phase. Changes in nutrient content and availability in the soil solution can vary among soil types in response to humic acid concentrations, thereby affecting Brachiaria growth. However, there are no studies demonstrating these effects of humic acid application on different soil types and how they affect Brachiaria growth. Thus, the aim of this study was to evaluate the effects of humic acid concentrations (0, 5, 10, 25, and 60 mg kg−1 carbon-humic acid) on Brachiaria brizantha growth and soil solution properties of contrasting tropical soils. Plants were grown for 35 days in greenhouse conditions in pots containing Sandy Entisol, Clayey (Red Oxisol), and Medium Texture (Red-Yellow Oxisol). Soil solution was assessed for pH, electrical conductivity (EC), carbon, and nutrient content. Shoot and root dry matter, as well as macro and micronutrients accumulation in the shoot, were determined. In a soil type-dependent effect, pH, EC, and concentrations of nutrients in solutions changed in response to carbon-humic acid concentration. In the less-buffered soils, Sandy Entisol and Red-Yellow Oxisol, the addition of 30–40 mg kg−1 carbon-humic acid increased root proliferation by 76–89%, while Brachiaria biomass produced in all soils increased by approximately 30%. Levels of carbon in solution were high (>580 mg L−1) and varied depending on the investigated soil type. Though solution carbon contents did not appear to be a driving factor controlling the positive effects of humic acid concentrations on Brachiaria dry matter, there was a direct relationship between other properties and nutrient content in the soil solution, and Brachiaria dry matter production.

Synthesis and Thermodynamic Evaluation of Sialyl-Tn MUC1 Glycopeptides Binding to Macrophage Galactose-Type Lectin.

Interactions between the tumor-associated carbohydrate antigens of Mucin 1 (MUC1) and the carbohydrate-binding proteins, lectins, often lead to the creation of a pro-tumor microenvironment favoring tumor initiation, progression, metastasis, and immune evasion. Macrophage galactose binding lectin (MGL) is a C-type lectin receptor found on antigen-presenting cells that facilitates the uptake of carbohydrate antigens for antigen presentation, modulating the immune response homeostasis, autoimmunity, and cancer. Considering the crucial role of tumor-associated forms of MUC1 and MGL in tumor immunology, a thorough understanding of their binding interaction is essential for it to be exploited for cancer vaccine strategies. The synthesis of MUC1 glycopeptide models carrying a single or multiple Tn and/or sialyl-Tn antigen(s) is described. A novel approach for the sialyl-Tn threonine building block suitable for the solid phase peptide synthesis was developed. The thermodynamic profile of the binding interaction between the human MGL and MUC1 glycopeptide models was analyzed using isothermal titration calorimetry. The measured dissociation constants for the sialyl-Tn-bearing peptide epitopes were consistently lower compared to the Tn antigen and ranged from 10 μM for mono- to 100 nM for triglycosylated MUC1 peptide, respectively. All studied interactions, regardless of the glycan's site of attachment or density, exhibited enthalpy-driven thermodynamics.

3D Numerical Modeling to Assess the Energy Performance of Solid–Solid Phase Change Materials in Glazing Systems

This research investigates the energy efficiency of a novel double-glazing system incorporating solid–solid phase change materials (SSPCMs), which offer significant advantages over traditional liquid–solid phase change materials. The primary objective of this study is to develop a 3D numerical model using the finite volume method, which will be followed by a parametric study under real climatic boundary conditions. A proposed double-glazing setup featuring a 2 mm layer of SSPCM applied on the inner glass pane within the air gap is modeled and analyzed. The simulations consider various transient temperatures and ranges of the SSPCM to evaluate the energy performance of the system under different weather conditions of Miami, FL during the coldest and hottest days of the year, both in sunny and cloudy conditions. The results demonstrate a notable improvement in energy performance compared to standard double-glazing windows (DGWs), with the most efficient SSPCM configuration exhibiting a phase transition temperature and range of 25 °C and 1 °C, respectively. This configuration achieved energy savings of 24%, 26%, and 23% during summer sunny, winter sunny, and winter cloudy days, respectively, relative to DGWs during cooling and heating degree hours. However, a 3% energy loss was observed during summer cloudy days. Overall, the findings of this study have shown the potential for energy savings by incorporating SSPCM with suitable thermophysical properties into double-glazing systems.

Induction of Apoptosis and ROS Production in Liver Cancer Cells by Saponin Fraction from Alcea rosea L. Seeds

Background: Natural compounds are essential targets in anticancer research due to the toxic effects of current chemotherapy and drug resistance. Methods: Saponin extraction from Alcea rosea L. was carried out using 20% methanol and liquid-liquid extraction coupled with the Solid phase extraction (SPE) approach. The saponin fraction was explored for its cytotoxic activity against Huh-7 and MDA-MB-231 cancer cell lines and a non–cancer cell line (HUVEC). The cytotoxic activity and oxidative stress were assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and 2,7 dichlorofluorescein diacetate dyes respectively. The apoptotic potential was investigated using DAPI and acridine orange-ethidium bromide dual staining. Result: The saponin fraction exhibited cytotoxic potential against the cell lines investigated. The IC50 values of the saponin fraction were 49.02, 300 and 325 µg\mL against Huh-7, MDA-MB-231 and HUVEC cell lines, respectively. The cytotoxicity for the extract was dose-dependent. The saponin fraction calculated selectivity index (SI) value indicated high selectivity towards Huh-7 cells (SI = 6.62) compared with normal HUVEC cells. Huh-7 cells treated with saponin fraction showed cellular and nuclear morphological changes, such as apoptotic body formation and chromatin condensation, as observed using light and fluorescent microscopy. However, further investigation is required to assess the the saponin fraction as a potential therapeutic agent.

Strengthening Ti3SiC2/Cu brazed joint assisted with cold spray additive manufacturing: Lower brazing temperature through interdiffusion and graded reinforcement for stress relaxation

Graded composite fillers exhibit unique advantages in alleviating residual stress in ceramic/metal brazed joints. However, traditional methods for preparing graded composite fillers are often complex and may deplete their strengthening phases. In this study, cold spray additive manufacturing was employed to fabricate yttria-stabilized zirconia (YSZ)-Ti25Zr25Ni25Cu25-Ag graded composite coatings on Cu substrates to serve as fillers. The graded composite coatings and the resultant Ti3SiC2/Cu brazed joints were systematically characterized to elucidate the deposition mechanism of the coatings and its residual stress-relaxed mechanism. The bondings between particles in the coatings, based on their plastic deformation ability, were classified into noncrystalline weak bonds and homogeneous strong bonds. Both bondings facilitated the elemental interdiffusion between filler and Cu substrate during the heating process, which contributed to the formation of Ag-Cu eutectic. This significantly reduced the required brazing temperature and its induced residual stress. Furthermore, the solid phase transformation of graded-distributed YSZ within the brazing seam from tetragonal to monoclinic achieved a smooth thermal transition and releasing residual stress at the same time. Consequently, the shear strength of the brazed joint reached to the highest value of 110.23 ± 3.45 MPa, which was Much higher than the previously reported values. This study introduces a novel method for residual stress relaxation assisted with cold spray technology and broadens its application in the brazing field.

Ab Initio Molecular Dynamics Insight to Structural Phase Transition and Thermal Decomposition of InN

Extensive ab initio density functional theory molecular dynamics calculations were used to evaluate stability conditions for relevant phases of InN. In particular, the p-T conditions of the thermal decomposition of InN and pressure-induced wurtzite–rocksalt solid–solid phase transition were established. The comparison of the simulation results with the available experimental data allowed for a critical evaluation of the capabilities and limitations of the proposed simulation method. It is shown that ab initio molecular dynamics can be used as an efficient tool for simulations of phase transformations of InN, including solid–solid structural transition and thermal decomposition with formation of N2 molecules. It is of high interest, because InN is an important component of epitaxial quantum structures, but it has not been obtained as a bulk single crystal. This makes it difficult to determine its basic physical properties to develop new applications.

Development and validation of general plasma screening method for performance enhancing drugs in racehorses utilizing liquid chromatography-high-resolution mass spectrometry (LC-HRMS).

The screening of drugs in plasma and urine often requires initial extraction (such as liquid-liquid extraction and solid-phase extraction) before the samples are submitted to instrumental analyses. These extraction procedures are often laborious and time-consuming. In this manuscript, a high-throughput automated assay based on liquid chromatography-high-resolution mass spectrometry (LC-HRMS) suitable for use as an initial testing procedure covering multiple classes of compounds prohibited in horse racing is described. The assay requires a 600-μL plasma aliquot, which is subjected to solid phase extraction (SPE) using OASIS HLB 96-well SPE with Biotage Extrahera system, evaporation, and reconstitution in a 96-well collection plate. LC-HRMS analyses were carried out on a Thermo Q-Exactive Mass spectrometer coupled with Thermo UHPLC system equipped with Thermo Accela ALS 2.4.0 autosampler linked to ACE Excel column. Drug targets were detected by retention time and accurate mass, with a mass tolerance window of 5ppm in positive and negative ionization mode. The screening method was validated for over 300 drug targets in a 13-min run. Validation data including sensitivity, specificity, extraction recovery, and precision are presented. As the method employs full-scan mass spectrometry, unlimited number of drug targets can theoretically be incorporated into this method.

Transcriptomic analysis of different intramuscular fat contents on the flavor of the longissimus dorsi tissues from Guangling donkey

BackgroundIn this study, researchers aimed to explore the impact of intramuscular fat (IMF) concentration on the flavor of donkey meat, specifically in the longissimus dorsi muscle of Guangling donkeys. The internal volatile organic compounds that cause the flavor differences between donkey muscles are not clear at present. Transcriptomic technologies were utilized to analyze gene expression and its relationship to donkey meat flavor. MethodThirty Guangling donkeys had their IMF content evaluated in the longissimus dorsi muscle. Based on IMF content, 16 donkeys of similar ages were divided into two groups: low-fat (L) and high-fat (H). Headspace solid-phase microextraction Gas chromatography-mass spectrometry (HS-SPME-GC–MS) and headspace solid phase microextraction mass spectrometry were used to identify potential flavor components that differed between the two groups. ResultsFive key volatile substances were identified, and WGCNA and KEGG analysis was conducted to analyze the genes associated with these substances. The results showed that pathways like PPAR signaling, nucleotide excision repair, glucagon signaling, arachidonic acid metabolism, and glycolysis/glycogenesis were involved in lipid deposition. Additionally, a gene-gene interaction network map was constructed, highlighting the importance of hub genes such as EEF2, DDX49, GAP43, SNAP25, NDUFS8, MRPS11, RNASEH2A, POLR2E, POLR2C and ALB in regulating key flavor substances. ConclusionThis study provided valuable insights into the regulation of genes and protein expression related to flavor substances in donkey meat. It also deepened understanding of the influence of IMF on flavor and laid a foundation for future molecular breeding improvements in Guangling donkeys.