Search Results (58)

The principal difficulty in studying the physico-mechanical and filtration-capacity properties of coals and host rocks under laboratory conditions using core samples lies in reproducing natural thermodynamic conditions characteristic of in situ depths. To address this issue, specialized equipment and methodologies for transferring measurement results are employed, including the Hoek–Brown failure criterion, the structural weakening coefficient, and the development of thermodynamic models. The reliability and accuracy of such measurements are determined by the degree of conformity between the adopted laboratory conditions and natural in situ conditions, the number of samples representing different lithological varieties, and the adequacy of sampling procedures ensuring representativeness. Particular challenges arise when sampling cleated and fractured coals formed under natural stress–strain conditions and contain methane, which significantly influences their physical properties. These difficulties are especially pronounced in prepared-for-mining high-gas-content coal seams of the Karaganda Basin at depths of approximately 700 m, where obtaining representative samples is technically complicated. Reliable values of the physico-mechanical properties of the coal–rock mass are essential for geomechanical calculations aimed at ensuring safe mining of high-gas-content seams through risk assessment of geodynamic phenomena, particularly in zones of geological disturbances, floor heave, and roof collapse. In this context, the use of a comprehensive suite of geophysical logging data from exploration boreholes makes it possible to obtain continuous, high-precision information on physico-mechanical and filtration-capacity properties. These methods are particularly important for characterizing the coal–rock mass in operating mines, since the natural state of host rocks and prepared coal seams is altered due to stress relief caused by mine workings, preliminary degasification measures, and hydraulic fracturing. The problem addressed is the need for reliable assessment of rock and coal seam parameters under natural thermodynamic stress–strain conditions, taking into account lithological composition, structural heterogeneity, fracture development, stratigraphic differentiation, and gas saturation. The aim of this study is to ensure efficient and safe coal extraction based on geomechanical calculations utilizing physico-mechanical and filtration-capacity properties of host rocks and gas-bearing coal seams, whether prepared for mining or not yet extracted. The research methods are based on an integrated complex of geophysical logging of exploration wells, specialized software tools, and statistical processing techniques to identify patterns in physico-mechanical and filtration-capacity properties of host rocks and coal seams under natural stress–strain conditions, as well as to determine the nature of changes in these properties within coal seams and roof and floor rocks in prepared mining areas. The physico-mechanical and filtration-capacity properties of host rocks and coals from the Lenin and Kazakhstanskaya mines were determined. Regularities governing the application of these parameters to coals of different formations and depths were established; fracture orientations and characteristics were evaluated; and relationships between changes in coal seam parameters and gas content were identified. A comprehensive methodological framework for studying the physical and capacity properties of the coal–rock mass under natural thermodynamic conditions has been developed. Its primary application is the investigation of coal seams prepared for mining to support geomechanical calculations for efficient and safe coal extraction, the implementation of degasification measures for high-gas-content seams, and the assessment of gas-dynamic risks based on the character of variations in physical parameters. Full article

Objective: The purpose of this study was to assess the outcome of sinus grafting with a beta-tricalcium phosphate/hydroxyapatite (ß-TCP/HA) alloplast particulate biofunctionalized with cross-linked hyaluronic acid (xHya), comparing two surgical access techniques. Clinical, histological, histochemical, immunohistochemical and histomorphometrical parameters were used to characterize the tissue samples, which were retrieved at the second surgery for implant placement five months after sinus floor elevation (SFE). Materials and Methods: Twenty patients with a residual bone height ≤ 4 mm, estimated by a Cone Beam Computed Tomography (CBCT), were randomly allocated either to an innovative transcrestal sinus floor elevation (tSFE = tests) approach or a conventional lateral window approach (lSFE = controls) using piezoelectric preparation. The tSFE was carried out using the hydraulic Jeder^®-System. Grafting in both groups was performed using a ß-TCP–HA combination, which was biofunctionalized with a cross-linked hyaluronic acid. For both access techniques, a cross-linked collagen membrane covered either the bone window or transcrestal osteotomy. For second-stage surgery, a second CBCT was used to assess the bone volume and possible implant positioning to compare it with the baseline CBCT. Bone cores were harvested at implant placement and evaluated histomorphometrically. Patients were followed for 1-year post-op for survival rate estimation. Non-superiority was hypothesized for both surgical methods; thus, the primary outcome measure assessed different discomfort levels using patient-reported outcome measures (PROMs) for each therapeutic approach. Secondary outcomes were the volume change in subantral bone after sinus floor elevation, the chance of placing a 10 mm long implant with no need for additional augmentation, histological evaluation of the newly gained tissue, and implant integration and one-year survival. Results: Eighteen patients (n = 18/20) qualified for implant placement at five months, and ten donated tissue biopsies for microscopic analysis. Primary outcome reporting using PROMs was discarded due to truncated patient enrollment. The secondary parameter, placement of a ≥10 mm long implant without additional augmentation, was achieved for nine sites/patients from the lSFE control group. All patients from the tSFE test group received an implant that was positioned alongside additional augmentation. In both groups, all implants integrated and were functionally loaded. A total of 10 core samples (3 from the tSFE group and 7 from the lSFE group) were obtained and analyzed. Microscopically, new bone formation appeared consistent in all obtained samples. Specimens revealed advanced and ongoing osteogenesis, with most histological markers reacting positively in the immunohistochemical (IHC) staining. The histomorphometric calculation revealed that a mean of 61.17 ± 16.55% of the total area was occupied by newly formed bone, 30.43 ± 10.09% by connective tissue and 8.92 ± 15.29% by residual graft substitute. One-year follow-up of the loaded implants showed a 100% implant survival rate. Conclusions: Biofunctionalizing ß-TCP + HA particulate with cross-linked hyaluronic acid in sinus floor elevation procedures appears to be a safe and beneficial approach, resulting in satisfactory clinical, radiographic and histological parameters. In our study population, which presented with very atrophic residual subantral bone conditions, the hydrodynamic transcrestal sinus floor elevation method required a back-up treatment by the conventional lateral approach. Full article

Exogenous toxic compounds in foods, arising from agricultural practices, environmental contamination, industrial processing, and packaging migration, remain a major global concern for food safety. These contaminants include mycotoxins, veterinary drug residues, antibiotics, pesticides, per- and polyfluoroalkyl substances, heterocyclic aromatic amines, and polycyclic aromatic hydrocarbons, which have multiple adverse effects on human and animal health. The continued presence of these substances highlights the need for reliable exposure assessment, strengthened regulatory frameworks, and advanced analytical methodologies. Food matrices introduce variability in analytical performance, making sample preparation a critical and often limiting step. Conventional extraction techniques such as solid-phase extraction, liquid–liquid extraction, and Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) are still widely applied. Moreover, recent advances have highlighted sustainable alternatives aligned with the principles of green analytical chemistry. In this context, this review provides a comprehensive overview of recent advances (2020–2025) in environmentally friendly extraction techniques for determining exogenous toxic compounds in food samples analyzed by liquid chromatography coupled with mass spectrometry (LC–MS), including their sustainability. Special attention is given to the chemical nature and toxicological relevance of major exogenous organic contaminant families (specialized categories such as hormones and packaging-derived bisphenols were excluded due to distinct migration and metabolic pathways; however, these topics exceed the scope of this manuscript), the analytical challenges associated with different food matrices, and the evolution of extraction and cleanup techniques. Overall, this review integrates analytical robustness, matrix effects, and green metrics to support the development of reliable and more sustainable sample preparation strategies. Full article

This study aimed to establish a fast and efficient method for the determination of N-nitrosamines (NAs) in meat products by integrating two sample preparation techniques—QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) and FaPEx (Fast Pesticide Extraction)—with liquid chromatography–tandem mass spectrometry (LC–MS/MS). Chromatographic separation was performed on a Poroshell 120 Phenyl Hexyl column using a gradient elution of acetonitrile and 0.01% formic acid at a flow rate of 0.3 mL/min and a column temperature of 25 °C. Under these conditions, nine NAs and one internal standard were completely separated within 11 min with selective reaction monitoring mode (SRM) for detection. Samples were first extracted with QuEChERS powder using acetonitrile containing 0.1% formic acid, followed by purification with a FaPEx-Chl cartridge. This combined approach demonstrated superior performance compared with traditional solvent extraction or QuEChERS extraction alone. The recoveries of the developed method ranged from 76% to 111% and 52% to 103% at spiking levels of 50 ng/g and 20 ng/g, respectively. The limits of detection (LOD) and quantification (LOQ) were 0.002–0.3 ng/g and 0.006–1.00 ng/g, respectively. The inter-day and intra-day precisions (RSD%) ranged from 2.7% to 17% and 2.9% to 17%, respectively. These results indicate that the proposed method is among the most time-efficient and effective analytical approaches currently available for the determination of NAs in meat products. Full article

This review provides a comprehensive evaluation of recent advances in miniaturized Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) sample preparation techniques applied across food, environmental, and biological matrices. Covering developments within 2020–2025, it focuses on analytical performance, environmental impact, and alignment with principles of sustainable and green analytical chemistry. Central to this review is the significant reduction in solvent and sample volumes achieved through miniaturization, thus decreasing the reagent consumption and hazardous waste generation. The integration of eco-friendly extraction solvents and sorbent materials enhances selectivity and reduces the environmental footprint. These methods are often coupled with high-resolution mass spectrometers, enabling sensitive, multi-residue, and suspect analysis. Challenges associated with complex matrices, low analyte concentrations, and the need for robust clean-up procedures are addressed through innovative hybrid workflows and advanced materials, e.g., polymeric electrospun fibers and deep eutectic solvents. The growing adoption of greener protocols is highlighted. Moreover, it underscores their potential to improve routine analytical workflows while reducing environmental burden. Future research should focus on the development of sustainable sample preparation with improved sensitivity, broader applicability, and minimal ecological impacts. This comprehensive assessment supports the ongoing transformation of analytical chemistry towards more sustainable practices without compromising analytical reliability and efficacy. Full article

High brittleness severely restricts the practical use of nanocrystalline cores in low-frequency power electronics. To enhance mechanical strength and facilitate cutting and transportation, curing techniques are commonly employed, yet their influence on the magnetic properties of the cores remains unclear. In this work, three curing techniques, namely, fluid-phase adhesive curing, gel-phase adhesive curing, and vacuum-evacuated gel-phase adhesive curing (VGAC), are applied to prepare cores with varying curing degrees. The magnetic properties of them are quantitatively compared with those of uncured cores within the range of 50–550 Hz. Results show that all three curing techniques demonstrably reduce the eddy current losses of the cores. Specifically, the VGAC-based core exhibits a 50% reduction in eddy current loss compared to the uncured core at 550 Hz and 0.8 T. Meanwhile, high saturation flux density is retained in all cured samples. However, curing also reduces permeability and raises coercivity. Furthermore, cured cores demonstrate increased hysteresis and residual losses, leading to higher total losses. The relationship between core losses and temperature rise is also investigated to provide important guidance for the safe operation of cured cores. In addition, microscopic images under 200× magnification are presented to elucidate the mechanisms underlying these observed influences. Full article

Occupational exposure to soil-borne pesticides remains a critical safety and process-management challenge in industrial and agro-industrial settings. This work proposes a process-integrated analytical workflow that couples comparative instrumental identification of soil xenobiotics with an occupational risk assessment framework. We comparatively evaluate GC-MS (gas chromatography–mass spectrometry), HPLC (high performance liquid chromatography), FTIR (Fourier-Transform Infrared Spectroscopy), LC-MS/MS (Liquid Chromatography coupled with tandem Mass Spectrometry), and ICP-MS (Inductively Coupled Plasma Mass Spectrometry) against matrix complexity, sensitivity, cost, and throughput, and implement the Quick, easy, cheap, effective, rugged, safe (QuEChERS) method-based sample preparation followed by GC-MS and LC-MS/MS to demonstrate applicability on representative soil and food-chain samples. Complementary risk tools (toxicity–probability matrices, exposure pathway diagrams) and an integrated monitoring scheme that combines environmental data with biomonitoring are used to link concentrations to exposure potential and control priorities. In a soil case sample, low-level organochlorines were detected with total DDT at 0.010 mg/kg and total HCH at 0.003 mg/kg, illustrating how analytical outputs feed decision matrices for prioritizing interventions. Case analyses from agricultural and industrial contexts indicate that targeted substitution, optimized application, ventilation and dust control, PPE (personal protective equipment) adherence, and worker training can measurably reduce symptoms and biomarkers of exposure. Overall, a complementary, process-analytical approach—integrating sensitive multi-technique detection with exposure assessment and continuous monitoring—supports proactive risk management and aligns with process systems and monitoring themes. Recommendations include standardizing workflows, coupling routine environmental monitoring with biomonitoring where feasible, and embedding preventive policies and training into industrial management systems. Full article

Serial block-face scanning electron microscopy (SBEM) is a powerful technique for three-dimensional ultrastructural analysis of biological samples, though its application to in vitro cultured human cells remains underutilized. In this study, we present an optimized SBEM sample preparation protocol using human dermal fibroblasts and induced pluripotent stem cells (iPSCs). The method includes key modifications to the original protocol, such as using only glutaraldehyde for fixation and substituting the toxic cacodylate buffer with a less hazardous phosphate buffer. These adaptations result in excellent preservation of cellular ultrastructure, with high contrast and clarity, as validated by transmission electron microscopy (TEM). The loss of natural cell morphology resulted from fixation during passage, when cells formed a precipitate, rather than from fixation directly within the culture medium. The protocol is time-efficient, safe, and broadly applicable to both stem cells and differentiated cells cultured under 2D conditions, providing a valuable tool for ultrastructural analysis in diverse biomedical research settings. Full article

Nucleoside reverse transcriptase inhibitors (NRTIs) and platinum-based chemotherapeutics are widely utilized in cancer treatment. Evidence suggests that drug plasma concentrations are closely linked to both therapeutic efficacy and the risk of adverse effects. Consequently, developing therapeutic drug monitoring (TDM) methods is essential. Here, an effective procedure utilizing QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) techniques for preparing samples and UPLC-MS/MS for simultaneously measuring eight NRTIs and platinum-based drugs in human plasma is described. Chromatographic separation was conducted with an Agilent Eclipse Plus C18 column (4.6 × 100 mm, 3.5 μm) with acetonitrile with 0.1% formic acid as Phase A and 0.1% formic acid in water as Phase B, achieving complete separation within 10 min. The target analytes—lamivudine, telbivudine, emtricitabine, entecavir, tenofovir, nedaplatin, oxaliplatin, and adefovir dipivoxil—exhibited strong linearity within the 10–1000 ng/mL and 1–100 ng/mL ranges, showing correlations (r²) ≥ 0.9962. The method demonstrated excellent accuracy (−6.72% to 7.82%) and selectivity (84.53%–110.49%), as well as satisfactory recovery and stability. Overall, this analytical approach can be used to detect the combination of eight NRTIs and platinum-based drugs in human plasma. This method enables plasma drug-level monitoring in real time, with applications for individualized treatment approaches. Full article

We evaluated the efficacy of an innovative technique using an S3+ device equipped with two custom-made nanosensors (e-nose). These sensors are integrated into kitchen appliances, such as planetary mixers, to monitor and assess dough leavening from preparation to the fully risen stage. Since monitoring in domestic appliances is often subjective and non-reproducible, this approach aims to ensure safe, high-quality, and consistent results for consumers. Two sensor chips, each with three metal oxide semiconductor (MOS) elements, were used to assess doughs prepared with flours of varying strengths (W200, W250, W390). Analyses were conducted continuously (from the end of mixing to 1.5 h of leavening) and in two distinct phases: pre-leavening (PRE) and post-leavening (POST). The technique was validated through solid-phase micro-extraction combined with gas chromatography–mass spectrometry (SPME-GC-MS), used to analyze volatile profiles in both phases. The S3+ device clearly discriminated between PRE and POST samples in 3D Linear Discriminant Analysis (LDA) plots, while 2D LDA confirmed flour-type discrimination during continuous leavening. These findings were supported by SPME-GC-MS results, highlighting differences in the volatile organic compound (VOC) profiles. The system achieved 100% classification accuracy between PRE and POST stages and effectively distinguished all flour types. Integrating this e-nose into kitchen equipment offers a concrete opportunity to optimize leavening by identifying the ideal endpoint, improving reproducibility, and reducing waste. In future applications, sensor data could support feedback control systems capable of adjusting fermentation parameters like time and temperature in real time. Full article

Accurately characterizing the internal porosity rate of thermal barrier coatings (TBCs) was essential for prolonging their service life. This work concentrated on atmospheric plasma spray (APS)-prepared TBCs and proposed the utilization of terahertz non-destructive detection technology to evaluate their internal porosity rate. The internal porosity rates were ascertained through a metallographic analysis and scanning electron microscopy (SEM), followed by the reconstruction of the TBC model using a four-parameter method. Terahertz time-domain simulation data corresponding to various porosity rates were generated employing the time-domain finite difference method. In simulating actual test signals, white noise with a signal-to-noise ratio of 10 dB was introduced, and various wavelet transforms were utilized for denoising purposes. The effectiveness of different signal processing techniques in mitigating noise was compared to extract key features associated with porosity. To address dimensionality challenges and further enhance model performance, kernel principal component analysis (kPCA) was employed for data processing. To tackle issues related to limited sample sizes, this work proposed to use the Siamese neural network (SNN) and generative adversarial network (GAN) algorithms to solve this challenge in order to improve the generalization ability and detection accuracy of the model. The efficacy of the constructed model was assessed using multiple evaluation metrics; the results indicate that the novel hybrid WT-kPCA-GAN model achieves a prediction accuracy exceeding 0.9 while demonstrating lower error rates and superior predictive performance overall. Ultimately, this work presented an innovative, convenient, non-destructive online approach that was safe and highly precise for measuring the porosity rate of TBCs, particularly in scenarios involving small sample sizes facilitating assessments regarding their service life. Full article

Activated carbon (AC) and biochar (BC) are porous materials with large surface areas and widely used in environmental and industrial applications. In this study, different types of AC and BC samples were produced from Sargassum sp. by a chemical activation and pyrolysis process and compared to commercial activated carbon samples. All samples were characterized using various techniques to understand their structure and functionalities. The metal content of the samples was characterized by using an inductively coupled optical emission spectrometer (ICP-OES). A toxicity test was applied to investigate the effect of AC/BC on organisms, where Sinapis alba seed and Escherichia coli bacteria-based toxicity tests were used. The results revealed that the samples did not negatively affect these two organisms. Thus, it is safe to use them in various applications. Therefore, the samples were tested as fillers in polyurethane composites and, thus, polyurethane-AC/BC samples were prepared. The amounts of AC/BC mixed into the polyurethane formulation were 1%, 2%, and 3%. Mechanical and acoustic properties of these composites were analyzed, showing that by adding the AC/BC to the system an increase in the compression strength for all the samples was achieved. A similar effect of the AC/BC was noticed in the acoustic measurements, where adding AC/BC enhanced the sound adsorption coefficient (α) for all composite materials. Full article

The growing prevalence of pharmaceutical compounds in the environment raises significant concerns due to their potential impacts on ecological and human health. This present manuscript focuses on the methods used to extract and determine these pharmaceuticals in water samples. It provides a comprehensive analysis of the extraction techniques and analytical approaches employed for the identification and quantification of pharmaceuticals in environmental water. Due to their chemical properties and widespread use, pharmaceuticals persist in the environment and contaminate water bodies, soil, and sediments. The presence of pharmaceuticals in the aquatic environment has been linked to several adverse effects on aquatic organisms, including the disruption of physiological processes and reproductive impairment. Furthermore, pharmaceuticals in the environment can affect human health through food and drinking water contamination and contribute to antibiotic resistance. The analysis of pharmaceutical contaminants in water samples presents several challenges due to the complex matrix and low concentrations of target substances. Various sample preparation techniques and protocols, including solid-phase extraction (more than 76% of the studied literature) and QuEChERS (quick, easy, cheap, effective, rugged, and safe), coupled with liquid chromatography–tandem-mass spectrometry, are commonly used for their determination. These methods offer high sensitivity, selectivity, and efficiency in identifying and quantifying pharmaceuticals in environmental samples. It is, therefore, essential that ongoing research is conducted in order to develop more efficient analytical methods and mitigation strategies to address pharmaceutical contamination in the environmental water effectively. It is also crucial that increased awareness and regulatory measures are put in place in order to minimize the environmental and human health risks associated with pharmaceutical pollutants. Full article

The approval of safe and effective LNP-mRNA vaccines during the SARS-CoV-2 pandemic is catalyzing the development of the next generation of mRNA therapeutics. Proper characterization methods are crucial for assessing the quality and efficacy of these complex formulations. Here, we show that analytical ultracentrifugation (AUC) can measure, simultaneously and without any sample preparation step, the sedimentation coefficients of both the LNP-mRNA formulation and the mRNA molecules. This allows measuring several quality attributes, such as particle size distribution, encapsulation efficiency and density of the formulation. The technique can also be applied to study the stability of the formulation under stress conditions and different buffers. Full article

Background and Objectives: The pancreas, ensconced within the abdominal cavity, requires a plethora of sophisticated imaging modalities for its comprehensive evaluation, with ultrasonography serving as a primary investigative technique. A myriad of pancreatic pathologies, encompassing pancreatic neoplasia and a spectrum of inflammatory diseases, are detectable through these imaging strategies. Nevertheless, the intricate anatomical confluence and the pancreas’s deep-seated topography render the visualization and accurate diagnosis of its pathologies a formidable endeavor. The objective of our paper is to review the best diagnostic imagistic tools for the pancreas. Materials and Methods: we have gathered several articles using Prisma guidelines to determine the best imagistic methods. The imperative of pancreatic scanning transcends its diagnostic utility, proving to be a pivotal element in a multitude of clinical specialties, notably surgical oncology. Within this domain, multidetector computed tomography (MDCT) of the pancreas holds the distinction of being the paramount imaging modality, endorsed for its unrivaled capacity to delineate the staging and progression of pancreatic carcinoma. In synergy with MDCT, there has been a notable advent of avant-garde imaging techniques in recent years. These advanced methodologies, including ultrasonography, endoscopic ultrasonography, contrast-enhanced ultrasonography, and magnetic resonance imaging (MRI) conjoined with magnetic resonance cholangiopancreatography (MRCP), have broadened the horizon of tumor characterization, offering unparalleled depth and precision in oncological assessment. Other emerging diagnostic techniques, such as elastography, also hold a lot of potential and promise for the future of pancreatic imaging. Fine needle aspiration (FNA) is a quick, minimally invasive procedure to evaluate lumps using a thin needle to extract tissue for analysis. It is less invasive than surgical biopsies and usually performed as an outpatient with quick recovery. Its accuracy depends on sample quality, and the risks include minimal bleeding or discomfort. Results, guiding further treatment, are typically available within a week. Elastography is a non-invasive medical imaging technique that maps the elastic properties and stiffness of soft tissue. This method, often used in conjunction with ultrasound or MRI, helps differentiate between hard and soft areas in tissue, providing valuable diagnostic information. It is particularly useful for assessing liver fibrosis, thyroid nodules, breast lumps, and musculoskeletal conditions. The technique is painless and involves applying gentle pressure to the area being examined. The resulting images show tissue stiffness, indicating potential abnormalities. Elastography is advantageous for its ability to detect diseases in early stages and monitor treatment effectiveness. The procedure is quick, safe, and requires no special preparation, with results typically available immediately. Results: The assembled and gathered data shows the efficacy of various techniques in discerning the nature and extent of neoplastic lesions within the pancreas. Conclusions: The most common imaging modalities currently used in diagnosing pancreatic neoplasms are multidetector computed tomography (MDCT), endoscopic ultrasound (EUS), and magnetic resonance imaging (MRI), alongside new technologies, such as elastography. Full article