Solid Samples Research Articles

Evaluation of coal mine drainage and associated precipitates for radium and rare earth element concentrations

Coal mine drainage (CMD) and associated metal-rich precipitates have recently been proposed as unconventional sources of rare earth elements (REEs). However, the potential occurrence of radium (Ra), a known carcinogen, with the REE-bearing phases has not been investigated. We hypothesized that Ra may occur in solids that are precipitated from CMD as a “radiobarite” solid solution ((Ba,Sr,Ra)SO4) and/or adsorbed with hydrous metal oxides. REEs have been documented to sorb or co-precipitate with iron (Fe), manganese (Mn), and aluminum (Al) oxyhydroxide in CMD solids. Likewise, Ra has been documented to sorb to hydrous Fe and Mn oxides especially where sulfate (SO4) and/or barium (Ba) concentrations are insufficient to precipitate radiobarite. Thus, we conducted the first-ever survey of Ra concentrations in corresponding CMD water and solid samples in the United States. Samples were analyzed from 4 untreated and 9 treated CMD sites in both the bituminous and anthracite coal regions of Pennsylvania across a range of pH and SO4 concentrations. The dissolved Ra in CMD was relatively low (<0.5 Bq/L), consistent with radiobarite solubility; however, CMD solids were largely composed of amorphous Fe, Al, and Mn oxyhydroxide and silicate minerals. Ra was associated with Mn-enriched CMD solids, upwards of 875 Bq/kg. Total REE + yttrium (Y) content in the CMD solids was enriched upwards of 3600 mg/kg and was significantly correlated with Al content. These preliminary results suggest that REE extraction may target Al-rich solids to avoid Ra in Mn-rich solids.

Leadership in the digital era: Exploring the nexus between leadership styles and job satisfaction. The mediating role of perceived organizational politics in Jordanian insurance companies

The study intends to determine how leadership techniques adjusted to the trends impact employee job satisfaction, considering the mediating influence of perceived organizational politics in light of the expanding influence of digital technology and virtual work settings. The study included a solid sample of 300 workers from different parts of Jordan. The employees filled out the questionnaire anonymously. 5-point rating Likert scales were used to capture a range of viewpoints. Using the Partial Least Squares software, this study applies Structural Equation Modelling analysis to examine the relationships between job satisfaction, perceived organizational politics, and leadership styles in Jordanian insurance companies. The study focuses on all employees of insurance companies in Jordan, including people working at various administrative levels. The most common length of job tenure was between one and five years (38.67%). Initial results show a strong beneficial relationship between transformational leadership philosophies and contentment at work (β = 0. 378, t = 6.266, LL = 0.483, UL = 0.718, p &amp;amp;lt; 0.001). Similarly, transformational leadership had the highest standardized effect on perceived organizational politics with a coefficient of 0.443. Furthermore, the complex processes by which leadership philosophies tangentially affect job satisfaction levels are revealed by the role of mediation of perceived organizational politics.

Controlling the Solubility, Release Rate and Permeation of Riluzole with Cyclodextrins.

Riluzole (RLZ), a sodium channel-blocking benzothiazole anticonvulsant BCS class II drug, is very slightly soluble in aqueous medium. To improve aqueous solubility and modulate dissolution rate and membrane permeability, complex formation of RLZ with two cyclodextrin, α-cyclodextrin (α-CD) and sulfobutylether-β-cyclodextrin (SBE-β-CD), was studied. The stability constants demonstrated a greater affinity of SBE-β-CD towards RLZ compared to α-CD. A solubility growth of 1.7-fold and 3.7-fold with α-CD and SBE-β-CD, respectively, was detected in the solutions of 1% cyclodextrins and accompanied by the permeability reduction. For 1% CD solutions, several biopolymers (1% w/v) were tested for the membrane permeability under static conditions. The synergistic positive effect of α-CD and polymer on the solubility accompanied by unchanged permeability was revealed in RLZ/α-CD/PG, RLZ/α-CD/PEG400, and RLZ/α-CD/PEG1000 systems. Solid RLZ/CD complexes were prepared. Dynamic dissolution/permeation experiments for the solid samples disclosed the characteristic features of the release processes and permeation rate through different artificial membranes. The maximal permeation rate was determined across the hydrophilic semi-permeable cellulose membrane followed by the lipophilic PermeaPad barrier (model of intestinal and buccal absorption) and polydimethylsiloxane-polycarbonate membrane (simulating transdermal delivery way). Different mode of the permeation between the membranes was estimated and discussed.

Comparative analysis of actionable gene reporting in targeted panels versus comprehensive NGS testing for solid tumor samples.

11185 Background: The landscape of actionable genes significantly influences clinical decisions in cancer diagnosis, prognosis, and treatment planning. In a clinical context, the selection of NGS panels hinges on striking a balance among informative data, insurance coverage, and the preferences of patients and healthcare providers. Molecular pathology reference laboratories commonly employ large-scale next-generation sequencing (NGS) testing, curating smaller, disease-specific targeted panels. This study investigates the prevalence of unreported actionable genes in real-world clinical samples subjected to disease-specific panels. Methods: We analyzed SNV/InDel DNA variants in 795 clinical solid tumor samples using the Illumina TSO 500 platform for comprehensive NGS panel testing of 517 genes. Comprehensive NGS panel-tested samples were intersected with disease-specific targeted NGS panels for breast (54 genes), brain (62 genes), colorectal (36 genes), and lung (44 genes). An artificial filter was applied to align targeted panels with patient disease. Variants were classified based on pathogenicity, and benign variants were filtered out. Detected variants were assessed for actionable mutations as defined by the FDA recognized OncoKB actionable gene database criteria. Additionally, 1484 lung patient samples tested with a lung-specific targeted panel were de-identified and unmasked to the comprehensive NGS tumor profiling to investigate the prevalence of actionable alteration beyond those covered by the disease-specific panel. Results: The study revealed that 3.2% of breast, 0% of brain, 66.2% of colorectal, and 2.7% of lung samples had additional actionable mutations undisclosed by the targeted panels. The number of actionable genes beyond those included in the targeted panels were 14 for breast, 2 for brain, 25 for lung, and 41 for colorectal cancer. This underscores the importance of comprehensive testing to fully capture each patient tumor’s actionable mutation profile. Conclusions: Our findings detect masked actionable mutations in down-sampled targeted panels and highlight the need for comprehensive testing to accurately identify actionable mutations in various cancer types. Reporting actionable mutations can significantly influence clinical decision-making, emphasizing the importance of NGS test selection in routine molecular diagnostics as well as the impact of integrating comprehensive NGS testing.

A self-made tube cracker coupled to an EA-IRMS-AGE3 system

AbstractThe automatic graphitization system (AGE3) by IonPlus is very popular among radiocarbon dating laboratories. Usually, solid samples are burnt in an elemental analyzer (EA), and the gaseous CO2 is transferred for graphitization. Our system is coupled also with an isotope ratio mass spectrometer (IRMS), which measures the δ13C and δ15N of that gas. Some less routine pretreatment protocols require the production of gaseous samples and prevent the possibility of using the EA-AGE3 system, as the EA is used for solid samples only. In order to use that system, including the measurements of stable isotopes, we developed a glass tube cracker that connects to the EA. The device is routinely used in our laboratory and is mainly built from Swaglok catalog parts. We show that the background (blank) levels of a marble standard are indistinguishable between using the cracker and burning solid marble using the EA. We further demonstrate that the δ13C values are consistent and that the extraction efficiency when using the device is above 93%. Full descriptions, drawings, and working protocol are supplied.

A new setup for measurements of absolute saturation vapor pressures using a dynamical method: Experimental concept and validation.

We describe a new experimental system for direct measurements of the absolute saturation vapor pressures of liquid or solid samples. The setup allows the isolation of the sample under steady conditions in an ultra-high vacuum chamber, where the measurement of the sample's vapor pressure as a function of its temperature can be performed in a range around room temperature and in a pressure range defined only by the applied absolute pressure sensor. We characterize the setup and illustrate its capability to measure saturation vapor pressures as well as enthalpies of evaporation around room temperature with explicit measurements on four liquid compounds (diethyl phthalate, 1-decanol, 1-heptanol, and 1-hexanol) for which accurate vapor pressures have previously been reported.

Establishing optimized staining protocol and cutoff values of pan-TRK immunohistochemistry for detecting NTRK fusions in solid tumors: A Chinese multicenter cross-sectional study.

e15160 Background: Using IHC to screen NTRK+ patients, followed by NGS confirmation, is a strategy recommended by ESMO guidelines. However, the current IHC staining protocol (Protocol) and cutoff value (CV) are suboptimal, resulting in limited screening performance. This study aims to optimize the Protocol and redefine the CV to improve the efficacy of pan-TRK IHC in screening NTRK fusions. Methods: 126 NTRK+ and 162 NTRK- solid tumor samples (spls), previously confirmed by NGS and/or FISH, were collected retrospectively from 12 hospitals across China in 2023. All spls were stained with VENTANA pan-TRK IHC assay by using two different Protocols: 1) the conventional one recommended by the manufacturer's instruction and 2) an amplification one that included additional amplification steps to enhance the staining. The IHC stained spls were interpreted based on the manufacturer's instruction, and the results were analyzed to calculate the CVs. The sensitivity, specificity, accuracy, PPV, and NPV based on these CVs and the CV reported in the literature were calculated. Results: 126 NTRK+ spls involve 25 fusion-partner types and 23 tumor types. IHC showed 35 NTRK- spls without staining, and 253 spls (126NTRK+/127NTRK-) stained. The staining predominantly localized to the cytoplasm and nucleus (132 cytoplasmic positive, 105 cytoplasmic and nuclear positive). Due to the limited samples with membrane staining, only CVs for cytoplasmic and nuclear staining were defined. In order to enhance the sensitivity and feasibility of the pan-TRK IHC assay in NTRK+ screening, the statistically calculated CVs were adjusted, and we recommended using the following CVs in clinical practice: 1) ≥1 intensity of cytoplasmic staining in ≥50% of tumor cells and/or 2) ≥1 intensity of nuclear staining in any percentage of tumor cells. Compared with the statistically calculated CVs, although the accuracy of the recommended CVs was slightly reduced (87.5% vs 93.75%), the sensitivity was improved (94.44% vs 89.68%). The sensitivity and specificity of the recommended CVs were higher than that of the previously reported CV (≥1%): sensitivity (94.44% vs. 87.9%) and specificity (82.1% vs. 81.1%). Conclusions: The pan-TRK IHC assay demonstrated high sensitivity while maintaining good specificity and accuracy, improving screening and enrichment efficacy for identifying NTRK fusions in solid tumors by utilizing the amplification protocol and the recommended CVs. Clinical trial information: ChiCTR2200066850 . [Table: see text]

Thickness-Independent Reference-Plane-Invariant Noniterative Permittivity Extraction of Low-Loss Solid Dielectric Samples by Combined Use of Frequency- and Time-Domain Analyses

Thickness-Independent Reference-Plane-Invariant Noniterative Permittivity Extraction of Low-Loss Solid Dielectric Samples by Combined Use of Frequency- and Time-Domain Analyses

Characterization of diverse targetable ERBB2 alterations in 512,993 patients with solid tumors.

3129 Background: Trastuzumab deruxtecan (T-DXd) is an antibody-drug conjugate (ADC) that has demonstrated activity against a range of HER2-expressing and HER2-mutant (mut) solid tumors. We present an extensive landscape of ERBB2 alterations (alt) that may predict sensitivity to HER2-targeted therapies in development with a focus on mutations and cancer types without approved indications. Methods: We queried institutional databases (MSKCC and Foundation Medicine, Inc.) of comprehensive genomic profiling (CGP) performed on solid tumor tissue samples using either MSK-IMPACT (N=83,332; MSK) or FoundationOne/FoundationOne CDx (N=429,661; FMI) and on patient-matched liquid biopsies using FoundationOne Liquid CDx (N=1,922). ctDNA tumor fraction (ctDNA TF) on FoundationOne Liquid CDx was estimated using a composite algorithm. Clinicopathological characteristics and treatment outcomes were annotated for MSK-IMPACT samples. Results: ERBB2 activating alt were detected in 6.6% (n=28,508) and 5.0% (n=4,133) of tumors in the FMI and MSK cohorts, respectively. In FMI tissue samples, ERBB2 alt were most prevalent in gastroesophageal (GEC; 18.1%), bladder (18.0%), salivary gland (14.1%), breast (12.7%), and uterine (12.1%) cancers. The cancer types with the largest number of ERBB2mut tumors, specifically, included NSCLC (n=1,618, 1.9%), breast (n=1,565, 3.5%), colorectal (CRC; n=1,221, 2.3%), bladder (n=855, 8.8%), and GEC (n=660, 3.4%). Across these 5 cancers, ERBB2 mut were most commonly located in the kinase domain (KD; 58%), followed by the extracellular domain (ECD; 28%) and transmembrane domain (TMD; 2%). Rare splice site mut and in-frame deletions resulting in exon 16 loss (Ex16Alt) were also observed (n=76, &lt;0.1%). ERBB2 mut were found to be mutually exclusive with other RTK/MAPK driver oncogenes including: EGFR, KRAS, ALK, MET, BRAF, and RET in NSCLC; FGFR1 in breast cancer; BRAF in CRC; and FGFR3 in bladder cancer. In patient-matched liquid biopsy samples, sensitivity for detecting ERBB2 amplifications (amp; 33.3%, 43/129) was lower than for detecting ERBB2 mut (72.3%, 47/65) across select cancers. However, sensitivity for detection of both alts was improved in liquid samples with elevated ctDNA TF (≥1%), increasing to 52.6% (40/76) for amp and 97.3% (36/37) for mut. In the MSK cohort, 110 of 986 (11.2%) patients with ERBB2 mut non-NSCLC tumors received one or more HER2-targeted therapies, including ADCs. Clinical responses to HER2-targeted therapies were observed in patients harboring KD mut (n=10), ECD mut (n=6), TMD mut (V659E, n=1), and in 1 patient with a V697L mut. Conclusions: CGP detects diverse ERBB2activating alt at a high incidence in solid tumor types beyond NSCLC. These represent patient populations who may benefit from HER2-directed therapies. Trials of novel HER2-targeted agents are necessary to refine our understanding of the biological dependency of HER2 alterations.

Expression of alternatively spliced PD-L1 RNA with skipping of transmembrane domain.

e14596 Background: Programmed death-ligand 1 (PD-L1) is a transmembrane ligand for the programmed cell death protein 1 (PD-1), a receptor that inhibits T-cell activity. The PD-L1/PD-1 immune checkpoint axis has been successfully targeted to enhance antitumor immune responses. This gene is composed of seven exons. Exons 1-4 are responsible for the extracellular domain, exon 5 for the transmembrane domain, and exons 6-7 for the intracellular domain. Emerging data indicates that alternative splicing in genes is an important mechanism for expression of different isoforms that may influence antibody-based therapies. We explored the potential of the presence of alternative splicing in PD-L1 transcripts via sequencing of PD-L1 RNA in patients with various type of solid tumor cancers. Methods: RNA was extracted from 3443 FFPE solid tumor samples including lung, colon, pancreas, breast, and other cancer types. In addition, cfRNA was extracted from 532 peripheral blood plasma samples from patients with solid tumor cancers. RNA was sequenced using a hybrid capture targeted RNA panel on FFPE samples and peripheral blood with analysis focused on PD-L1 gene transcript. Quantification of RNA transcript was done using Salmon algorithm. Results: Of the 3443 FFPE samples, 38 (1.2%) samples showed alternative splicing involving deletion of exon 5 (PD-L1∆Ex5). The alternative splicing was in 2.10% of lung cancer, 2% of colon cancer, 0.70% of pancreatic cancer, 1.40% of gastric cancer, 0.38% of breast cancer, 0.30% of ovarian cancer, 1.10% of sarcoma cases, 1.50% of glioblastomas, 3.30% of thyroid cancer and 2% of urothelial cancer. Of the 532 cfRNA samples, 20 (3.7%) showed PD-L1∆Ex5. The median percentage of PD-L1∆Ex5 transcripts was 2.2% of total PD-L1 transcripts in tissue samples as compared with 6.6% in cfDNA samples. In tissue samples, there was a correlation between levels of PD-L1 and PD-L1∆Ex5 (r = .567, p &lt; .001). In contrast, cfRNA showed no significant correlation between levels of PD-L1 and levels of PD-L1∆Ex5 (r = .268). Conclusions: PD-L1 exon 5 skipping was detected in a number of patients with different types of solid tumor cancers. The percentage of skipping transcripts is low in cells and relatively higher in cfRNA. Since exon 5 skipping deletes the transmembrane domain, the PD-L1 protein may remain in the cytoplasm or perhaps is secreted as cell-free PD-L1 protein. The demonstration of relatively higher levels of PD-L1∆Ex5 in cfRNA is likely reflecting higher turnover of cells and raises the possibility that cells with this isoform of PD-L1 are more aggressive than cells without the expression of this isoform. Further studies are needed to explore the clinical relevance of the expression of such abnormal PD-L1 protein on treatment with immune checkpoint inhibitors.

Performing Suction Blister Skin Biopsies.

Traditional skin sampling methods include punch or shave biopsies to produce a solid tissue sample for analysis. These biopsy procedures are painful, require anesthesia, and leave permanent scars. This unit describes a suction blister skin biopsy method that can be used in place of traditional biopsy methodologies as a minimally invasive, non-scarring skin sampling technique. The induction of suction blisters uses an instrument with a chamber that applies negative pressure and gentle heat to the skin. Blister formation occurs within 1 hr, producing up to five blisters, each 10 mm in diameter per biopsy site. Blister fluid can be extracted and centrifuged to retrieve cells from the epidermis and upper dermis for flow cytometry, single-cell RNA sequencing, cell culture, and more without the need for digestion protocols. In addition, the blister fluid can be used to measure soluble proteins and metabolites. This unit describes the preparation of supplies and subjects, the suction blister biopsy procedure and blister formation, fluid extraction, and post-blistering care. © 2024 Wiley Periodicals LLC. Basic Protocol 1: Preparation of supplies and subject Basic Protocol 2: Suction blister biopsy procedure and formation Basic Protocol 3: Blister fluid extraction Basic Protocol 4: Post-blister care and clean up.

Prediction of CCL2 in breast cancer based on enhanced MRI radiomics model with integrated bioinformatics analysis and machine learning.

e12509 Background: Breast cancer is the most common malignant tumor in women. According to the 2023 Cancer Statistics Report, breast cancer has surpassed lung cancer to become the most common malignant tumor. Its incidence and mortality both rank first among female malignant tumors. This study proposes non-invasive prediction of CCL2 mRNA expression in breast cancer tissue through enhanced MRI radiomics, while integrating bioinformatics analysis to explore the underlying molecular mechanisms and their association with the immune microenvironment. Methods: Excluding criteria were applied to select primary solid tumor samples with RNA-seq data (n = 840) from the TCGA-BRCA database. Enhanced MRI imaging data (n = 98) intersecting with the TCGA-BRCA data were obtained from TCIA-BRCA. The imaging data were randomly divided into training (n = 70) and testing sets (n = 28) in a 7:3 ratio. A feature subset was selected, and a model was constructed using the support vector machine (SVM) algorithm in the training set. The predictive performance of the model was evaluated using receiver operating characteristic (ROC) curves, calibration curves, and the Hosmer-Lemeshow goodness-of-fit test. The calibration of the radiomics prediction model was assessed using the Brier score, and the clinical utility of the radiomics prediction model was demonstrated by drawing decision curves (DCA). External validation of the model was performed using a validation set. The radiomics score (RS) was calculated using the LR radiomics model and categorized as a binary variable (Low/High RS). Subsequently, KEGG pathway, immune-related genes, and gene mutation analysis were conducted based on the CCL2 high and low expression levels. Results: A total of 1810 radiomic features were obtained with ICC values ≥ 0.75. Subsequently, the mRMR (Maximum relevance, minimum redundancy) method, and the optimal 7 feature subsets were further identified using the RFE (Recursive feature elimination) algorithm. The SVM model demonstrated favorable predictive performance, with an AUC value of 0.822 for the training set and 0.779 for the validation set, as indicated by the ROC curve. Calibration curve and Hosmer-Lemeshow goodness-of-fit test revealed good consistency between the radiomic predictive model for the probability of high gene expression and the actual values (P &gt; 0.05). Additionally, the decision curve analysis (DCA) demonstrated high clinical utility of the model. The TNF-α signaling pathway was found to influence the occurrence and development of breast cancer. Furthermore, the degree of Plasma Cell infiltration was observed to be highest in breast cancer. Conclusions: The CCL2 model constructed using a combination of machine learning and radiomic features, can non-invasively predict the prognosis of breast cancer treatment and exhibits good generalizability.

Lexical pragmatic indicators of conflictogenicity in the information field of migration: Mexico - USA (based on Mexican social media)

The purpose of this study is to systematize the lexical pragmatic indicators of conflictogenicity (LPICs) used in Mexican user-generated content in the context of migration. The growth of anti-American attitudes caused by the speeches of D. Trump and his followers, as well as the socio-economic consequences of the influx of relocants from the USA to Mexico and their arrogant behavior contribute to the further formation of the image of the “Alien” in the Mexican linguistic picture of the world by the linguistic means of the conflictogenicity category. The study is based on user comments posted on the Mexican segment of Reddit, a popular online platform that combines the features of a social network and a forum where people can discuss various issues. About 3,000 comments posted over the past six years have been analyzed. The succession of two U.S. presidents during this period has had a great impact on the U.S. migration policy and its relations with Mexico. The LPICs were selected by the solid sampling method. Contextual method, method of communicative analysis, methods of component and pragmasemantic analysis were used too. As a result of the analysis, for the first time, the LPICs involved in the linguistic objectification of the image of the “Alien” in Mexican user-generated content – an English-speaking light-skinned foreigner – were identified and systematized. Both LPICs that initially have a negative connotation (invective and non-invective words of negative-evaluation): arrogant, greedy, invader, racist, disrespects Mexico, and LPICs that acquire it in ethno-cultural, socio-economic and personality-oriented contexts: Americans, English, English speakers, Mexico is a cheap country, etc. The increase in the density of LPICs used when discussing certain topics indicates the growing level of social tension in this sphere of public life.

Stereo-DIC Challenge 1.0 – Rigid Body Motion of a Complex Shape

BackgroundStereo-DIC is a widely used optical measurement technique that provides a dense full-field 3D measurement of the shape, displacement, and strain of a solid sample. When compared with 2D-DIC, Stereo-DIC provides greater flexibility and expands its use beyond flat, planar specimens. Furthermore, the widespread availability of commercial systems has led to the adoption of the technique throughout industry, academia, and government research labs.ObjectiveEven though some research has been done to understand the effects of different experimental and stereo-DIC parameters, no reference is available to benchmark and compare the performance of current stereo-DIC algorithms to each other.MethodsThis paper provides the description and analysis of a carefully controlled 3D experiment and associated images used to compare the results from five subset based DIC software packages. Both the images and analysis codes used in this paper to compare the results are described here and are available for download and use for continued research.ResultsWe show that over a very large range of motion, the 3D errors are very small, less than 80μ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\mu$$\\end{document}m over a travel of ±20 mm out-of-plane and ±20 mm in-plane. While all codes performed similarly, there are important differences noted in the paper.ConclusionThe image sets and results comparison software are hosted by the International DIC Society (www.iDICs.org) and are freely available for download and analysis for comparison with results in this paper. Furthermore, it is hoped that this set of images can be used for future research in improving stereo-DIC by future authors.

Study on the swelling of macromolecular geological organic matter with hydrocarbons and heteroatomic compounds

In this study, we conducted swelling experiments on eleven macromolecular geological organic materials using five types of organic solvents. Our primary objective was to investigate the absorption capacity of different solid organic materials in organic fluids and analyze the influence of their chemical structures. The samples utilized in this research included solid bitumen, kerogen, and coal samples from various basins. The chemical structure of the samples was assessed using solid-state 13C nuclear magnetic resonance (NMR), while X-ray diffraction (XRD) was employed to monitor any detect the structural changes during the swelling process. Our findings reveal that macromolecular geological organic compounds demonstrate a preferential expulsion of saturated hydrocarbons, followed by polycyclic aromatic hydrocarbons, upon interaction with liquid organic matter. The sulfur-containing compounds in solid organic matter demonstrated higher solubility than hydrocarbon compounds, while the solubility of oxygen-containing compounds varied based on the structure of the aliphatic chain and the proportion of oxygen atoms. This research, introduces LA [= Lac × Aac] as a new parameter to assess the combination of aliphatic chain length [Lac] and [Aac] abundance in solid organic matter. Furthermore, XRD testing revealed that the chemical structure unit of heteroatom compounds in solid organic matter consists of amorphous carbon, primarily composed of aliphatic chains. In this study, we evaluated the retention capacity of various macromolecular geological organic matter for both hydrocarbons and heteroatomic compounds. Additionally, the extent of swelling was investigated, providing theoretical support to diverse fields including organic petrology, petroleum geology, coal geology, and organic geochemistry.

Electric Field Effects in Flash Joule Heating Synthesis.

Flash Joule heating has emerged as an ultrafast, scalable, and versatile synthesis method for nanomaterials, such as graphene. Here, we experimentally and theoretically deconvolute the contributions of thermal and electrical processes to the synthesis of graphene by flash Joule heating. While traditional methods of graphene synthesis involve purely chemical or thermal driving forces, our results show that the presence of charge and the resulting electric field in a graphene precursor catalyze the formation of graphene. Furthermore, modulation of the current or the pulse width affords the ability to control the three-step phase transition of the material from amorphous carbon to turbostratic graphene and finally to ordered (AB and ABC-stacked) graphene and graphite. Finally, density functional theory simulations reveal that the presence of a charge- and current-induced electric field inside the graphene precursor facilitates phase transition by lowering the activation energy of the reaction. These results demonstrate that the passage of electrical current through a solid sample can directly drive nanocrystal nucleation in flash Joule heating, an insight that may inform future Joule heating or other electrical synthesis strategies.

Chromatographic approaches to food quality control by chemical compo-sition

The article provides an overview of chromatographic methods, which, when used comprehensively, ensure food quality control and safety. It considers gas chromatography methods that allow analysing volatile components in products using a flame ionization detector, an electron capture detector, and mass-selective detectors (GC-FID, GC-ECD, GC-MS, and GC-MS/MS). The article provides a list of analytes that can be detected by high performance liquid chromatography in combination with refractometric, spectrometric, and mass selective detectors (HPLC-RMD, HPLC-UV, HPLC-SPD, HPLC-MS, and HPLC-MS/MS). The study showed how ion chromatography and capillary electrophoresis with electrochemical detectors (IC-ECD, CE-ECD) can be used to detect ionogenic compounds. It highlighted the importance of thin layer chromatography (TLC) in combination with optical digital colour recording devices in the qualitative and quantitative analysis of contaminants in food products. Since it has been established that micro- and nanoplastics have a negative impact on human health, it is very important to detect these particles in food products. This task can be solved by using gel permeation chromatography (GPC) and hydrodynamic chromatography (HDC), as well as the method of field-flaw fractionation (FFF). It was shown that the GC-MS method is now becoming a priority instrumental method used in accredited analytical laboratories to identify impurities of contaminants in agricultural products. The pyrolytic GC-MS method is promising in this regard. The pyrolytic cell does not require the transfer of a solid sample into a solution for its analysis. The paper considers extraction and sorption methods for the preparation of samples for chromatographic analysis. A variety of liquid-liquid extraction (LLE) and solid-phase extraction (SPE.) methods are most commonly used. Recently, the QuEChERS method has been developed and widely implemented. The overview is primarily based on the papers dedicated to chromatography and related separation methods published by researchers belonging to Voronezh scientific schools.

Comparative Study of Bis-Schiff Case Containing Conjugated Oligomers Based on Phosphate and Silane Moieties: Investigation of Photophysical and Thermal Properties.

Oligo(azomethine)s bearing phosphate and silane moieties were the subject of an investigation within this study. The initial stage involved the synthesis of two Schiff base monomers, denoted as SCH-1 and SCH-2 (SCHs), each possessing a pair of hydroxyl functional groups. This was achieved through a loss of water between the aldehyde and diamine precursors. Subsequently, the Schiff base entities were subjected to oligomerization through HCl-mediated elimination due to the interaction between the hydroxyl groups of the Schiff bases and the chlorine moieties of dichlorodiethylsilane (Si) or phenyl dichlorophosphate (P). This procedure yielded distinct P-oligo(azomethine) (P1-P, P2-P) and Si-oligo(azomethine) (P1-Si and P2-Si) structures corresponding to each precursor. The molecular structures of the synthesized Schiff base monomers and oligo(azomethine)s were elucidated employing Fourier transform infrared, 1H NMR, and 13C NMR techniques. Thermal properties of the resulting products were assessed by utilizing thermogravimetric analysis (TG-DTG/DTA and DSC) techniques. Scanning electron microscopy (SEM) was employed to acquire high-resolution images and detailed surface information on the samples. Additionally, X-ray diffraction was employed to analyze the phase properties of the solid samples. Furthermore, the optical band gap (E g) values of the resulting P-oligo(azomethine)s and Si-oligo(azomethine)s were determined utilizing UV-vis spectrophotometer. The relatively low band gap values exhibited by the synthesized oligo(azomethine)s were indicative of their potential suitability as semiconductive materials in the realm of electronic and optoelectronic device fabrication. Photoluminescence (PL) measurements disclosed a green emission profile upon excitation by blue light. The oligo(azomethine)s incorporating methoxy groups demonstrated a red shift in comparison to their counterparts with methyl groups. Remarkably, no discernible fluctuations in fluorescence were observed over a 3600 s interval under consistent conditions. This observation underscored the inherent stability of the PL emission across the spectral range of exciting light. Thermal analyses unveiled high thermal stability of the synthesized oligo(azomethine)s, sustaining their structural integrity up to 220 °C. The char % of P-oligo(azomethine)s and Si-oligo(azomethine)s were observed to fall within the range of 29.45-55.47% at 1000 °C. SEM images revealed the absence of pores on the surface of P2-Si, which exhibited the highest limiting oxygen index and thermal heat release index (T HRI) values.

Bioorthogonal Quinone Methide Decaging Enables Live-Cell Quantification of Tumor-Specific Immune Interactions.

Effective antitumor immunity hinges on the specific engagement between tumor and cytotoxic immune cells, especially cytotoxic T cells. Although investigating these intercellular interactions is crucial for characterizing immune responses and guiding immunotherapeutic applications, direct and quantitative detection of tumor-T cell interactions within a live-cell context remains challenging. We herein report a photocatalytic live-cell interaction labeling strategy (CAT-Cell) relying on the bioorthogonal decaging of quinone methide moieties for sensitive and selective investigation and quantification of tumor-T cell interactions. By developing quinone methide-derived probes optimized for capturing cell-cell interactions (CCIs), we demonstrated the capacity of CAT-Cell for detecting CCIs directed by various types of receptor-ligand pairs (e.g., CD40-CD40L, TCR-pMHC) and further quantified the strengths of tumor-T cell interactions that are crucial for evaluating the antitumor immune responses. We further applied CAT-Cell for ex vivo quantification of tumor-specific T cell interactions on splenocyte and solid tumor samples from mouse models. Finally, the broad compatibility and utility of CAT-Cell were demonstrated by integrating it with the antigen-specific targeting system as well as for tumor-natural killer cell interaction detection. By leveraging the bioorthogonal photocatalytic decaging chemistry on quinone methide, CAT-Cell provides a sensitive, tunable, universal, and noninvasive toolbox for unraveling and quantifying the crucial but delicate tumor-immune interactions under live-cell settings.

Quantification of Zr in simulated dissolver solution of U–Zr fuel by laser-induced breakdown spectroscopy

Abstract Estimation of Zr in fresh and irradiated metal alloy fuel is important. The homogeneous dissolver solution represents the fuel composition better compared to a highly heterogeneous solid pellet. The present study employs LIBS to determine Zr in the simulated dissolver solution. Four different compositions of U–Zr samples where the Zr/U ratio varies from 0.04 to 0.18 % are analyzed by LIBS with an in-house designed liquid sample cell. A good correlation coefficient is achieved for the measurements in the calibration plot. The results for identifying non-overlapping peaks, calibration plot, precision, deviation, and detection limit are discussed in detail. Two set of solid samples, an oxide pellet and metal alloy with similar Zr/U composition, are also analyzed by LIBS. The results obtained from these three set of samples are inter-compared, and the reason for getting a better Zr/U intensity ratio for a dried coating of sample on aluminium for a given composition is explained.