In this work a simple, efficient, and environmentally-friendly method is proposed for determination of Be in soil and sediment samples employing slurry sampling and high-resolution continuum source electrothermal atomic absorption spectrometry (HR-CS-ETAAS). The spectral effects originating from SiO species were identified and successfully corrected by means of a mathematical correction algorithm. Fractional factorial design has been employed to assess the parameters affecting the analytical results and especially to help in the development of the slurry preparation and optimization of measuring conditions. The effects of seven analytical variables including particle size, concentration of glycerol and HNO3 for stabilization and analyte extraction, respectively, the effect of ultrasonic agitation for slurry homogenization, concentration of chemical modifier, pyrolysis and atomization temperature were investigated by a 27-3 replicate (n = 3) design. Using the optimized experimental conditions, the proposed method allowed the determination of Be with a detection limit being 0.016mgkg-1 and characteristic mass 1.3pg. Optimum results were obtained after preparing the slurries by weighing 100mg of a sample with particle size < 54µm and adding 25mL of 20% w/w glycerol. The use of 1μg Rh and 50μg citric acid was found satisfactory for the analyte stabilization. Accurate data were obtained with the use of matrix-free calibration. The accuracy of the method was confirmed by analysis of two certified reference materials (NIST SRM 2702 Inorganics in Marine Sediment and IGI BIL-1 Baikal Bottom Silt) and by comparison of the results obtained for ten real samples by slurry sampling with those determined after microwave-assisted extraction by inductively coupled plasma time of flight mass spectrometry (TOF-ICP-MS). The reported method has a precision better than 7%.
- Keywords
- Beryllium determination, Electrothermal atomic absorption spectrometry, Fractional factorial design, High-resolution continuum source AAS, Inductively coupled plasma mass spectrometry, Microwave-assisted extraction, Slurry sampling, Soil and sediment analysis,
- Publication type
- Journal Article MeSH
This paper assesses the instrumental resolution of a mechanical extensometer in light of its recent automatisation. The instrument takes advantage of the moire phenomenon of optical interference to measure angular rotation in two perpendicular planes and displacement in three dimensions. Our assessment systematically defines an analytical solution for the complete interpretation of a generic moire pattern and a set of mathematical approximations for the moire patterns used to measure rotation and displacement. The ultimate sensitivity of the automated instrument is determined on the basis of a generic least square differences fitting procedure while the instrumental resolution is defined on the basis of realistic, rather than optimal, scenarios: the resolution of the rotation measurements are in the order of 8.7*10-5 rad while the resolution of the displacement measurements are better than 5 μm. This assessment represents the first step towards a global numerical repository for processed data recorded by the automated extensometers.
- Keywords
- geological discontinuity monitoring, instrumental resolution, mechanical extensometer, moire patterns,
- Publication type
- Journal Article MeSH
The goal-directed control of behaviour critically depends on emotional regulation and constitutes the basis of mental well-being and social interactions. Within a socioemotional setting, it is necessary to prioritize effectively the relevant emotional information over interfering irrelevant emotional information to orchestrate cognitive resources and achieve appropriate behavior. Currently, it is elusive whether and how different socioemotional stimulus dimensions modulate cognitive control and conflict resolution. Theoretical considerations suggest that interference effects are less detrimental when conflicting emotional information is presented within a "positive socioemotional setting" compared with a "negative socioemotional setting." Using event-related potentials (ERPs) and source localization methods, we examined the basic system neurophysiological mechanisms and functional neuroanatomical structures associated with interactive effects of different interfering facial, socioemotional stimulus dimensions on conflict resolution. We account for interactive effects of different interfering socioemotional stimulus dimensions on conflict resolution, i.e., we show how the socioemotional valence modulates cognitive control (conflict processing). The data show that conflicts are stronger and more difficult to resolve in a negative emotional task-relevant setting than in a positive emotional task-relevant setting, where incongruent information barely induced conflicts. The degree of emotional conflict critically depends on the contextual emotional valence (positive or negative) in which this conflict occurs. The neurophysiological data show that these modulations were only reflected by late-stage conflict resolution processes associated with the middle (MFG) and superior frontal gyrus (SFG). Attentional selection processes and early-stage conflict monitoring do not seem to be modulated by interactive effects of different interfering socioemotional stimulus dimensions on conflict resolution.
- Keywords
- Conflict processing, EEG, Emotions, Faces, Source localization,
- MeSH
- Adult MeSH
- Emotions physiology MeSH
- Evoked Potentials physiology MeSH
- Humans MeSH
- Brain Mapping * MeSH
- Young Adult MeSH
- Attention physiology MeSH
- Negotiating psychology MeSH
- Facial Expression MeSH
- Check Tag
- Adult MeSH
- Humans MeSH
- Young Adult MeSH
- Male MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
Direct oral anticoagulants are an alternative to anticoagulants based on vitamin K antagonists. Monitoring of direct oral anticoagulant concentration levels is necessary in specific cases (e.g. in emergency conditions, for determination of the cause of bleeding, adverse effects, risk of drug-direct oral anticoagulants interaction); therefore, a sensitive and specific method is needed. A methanol protein precipitation method followed by liquid chromatography with high-resolution mass spectrometry was developed for simultaneous separation and determination of apixaban, betrixaban, edoxaban, dabigatran, rivaroxaban and ximelagatran. The proposed method was fully validated in terms of linearity, the limits of detection and quantification, intra- and inter-day trueness and precision, recovery, matrix effect, process efficiency and stability. The method shows a strong correlation (Pearson's correlation coefficients > 0.92) with coagulation assays of apixaban, dabigatran and rivaroxaban (dilute thrombin time for gatrans and anti Xa factor (anti-Xa) activity for xabans). In addition, the developed method was applied for the identification and determination of apixaban and dabigatran in post-mortem serum samples. The developed method is a good alternative to coagulation tests which may show various interferences.
- Keywords
- coagulation test, direct oral anticoagulant, high-resolution mass spectrometry, liquid chromatography, toxicology,
- MeSH
- Anticoagulants * administration & dosage blood isolation & purification toxicity MeSH
- Administration, Oral MeSH
- Chromatography, Liquid methods MeSH
- Mass Spectrometry methods MeSH
- Humans MeSH
- Linear Models MeSH
- Reproducibility of Results MeSH
- Sensitivity and Specificity MeSH
- Blood Coagulation Tests methods MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- Anticoagulants * MeSH
Collisions between replication and transcription machineries represent a significant source of genomic instability. RECQ5 DNA helicase binds to RNA-polymerase (RNAP) II during transcription elongation and suppresses transcription-associated genomic instability. Here, we show that RECQ5 also associates with RNAPI and enforces the stability of ribosomal DNA arrays. We demonstrate that RECQ5 associates with transcription complexes in DNA replication foci and counteracts replication fork stalling in RNAPI- and RNAPII-transcribed genes, suggesting that RECQ5 exerts its genome-stabilizing effect by acting at sites of replication-transcription collisions. Moreover, RECQ5-deficient cells accumulate RAD18 foci and BRCA1-dependent RAD51 foci that are both formed at sites of interference between replication and transcription and likely represent unresolved replication intermediates. Finally, we provide evidence for a novel mechanism of resolution of replication-transcription collisions wherein the interaction between RECQ5 and proliferating cell nuclear antigen (PCNA) promotes RAD18-dependent PCNA ubiquitination and the helicase activity of RECQ5 promotes the processing of replication intermediates.
- MeSH
- Models, Biological MeSH
- DNA-Directed RNA Polymerases metabolism MeSH
- DNA-Binding Proteins metabolism MeSH
- DNA-Directed DNA Polymerase metabolism MeSH
- Transcription Elongation, Genetic MeSH
- Stress, Physiological genetics MeSH
- Transcription, Genetic * MeSH
- HEK293 Cells MeSH
- RecQ Helicases metabolism MeSH
- Protein Interaction Domains and Motifs MeSH
- Humans MeSH
- Multienzyme Complexes metabolism MeSH
- Open Reading Frames genetics MeSH
- RNA Precursors genetics MeSH
- Proliferating Cell Nuclear Antigen metabolism MeSH
- BRCA1 Protein metabolism MeSH
- Rad51 Recombinase metabolism MeSH
- DNA Replication * MeSH
- DNA, Ribosomal metabolism MeSH
- Ubiquitination MeSH
- Ubiquitin-Protein Ligases metabolism MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- DNA-Directed RNA Polymerases MeSH
- DNA synthesome MeSH Browser
- DNA-Binding Proteins MeSH
- DNA-Directed DNA Polymerase MeSH
- RecQ Helicases MeSH
- Multienzyme Complexes MeSH
- RNA Precursors MeSH
- Proliferating Cell Nuclear Antigen MeSH
- BRCA1 Protein MeSH
- RAD18 protein, human MeSH Browser
- RECQL5 protein, human MeSH Browser
- Rad51 Recombinase MeSH
- DNA, Ribosomal MeSH
- Ubiquitin-Protein Ligases MeSH
Optical metasurfaces have emerged as a new generation of building blocks for multifunctional optics. Design and realization of metasurface elements place ever-increasing demands on accurate assessment of phase alterations introduced by complex nanoantenna arrays, a process referred to as quantitative phase imaging. Despite considerable effort, the widefield (nonscanning) phase imaging that would approach resolution limits of optical microscopy and indicate the response of a single nanoantenna still remains a challenge. Here, we report on a new strategy in incoherent holographic imaging of metasurfaces, in which unprecedented spatial resolution and light sensitivity are achieved by taking full advantage of the polarization selective control of light through the geometric (Pancharatnam-Berry) phase. The measurement is carried out in an inherently stable common-path setup composed of a standard optical microscope and an add-on imaging module. Phase information is acquired from the mutual coherence function attainable in records created in broadband spatially incoherent light by the self-interference of scattered and leakage light coming from the metasurface. In calibration measurements, the phase was mapped with the precision and spatial background noise better than 0.01 and 0.05 rad, respectively. The imaging excels at the high spatial resolution that was demonstrated experimentally by the precise amplitude and phase restoration of vortex metalenses and a metasurface grating with 833 lines/mm. Thanks to superior light sensitivity of the method, we demonstrated for the first time to our knowledge the widefield measurement of the phase altered by a single nanoantenna while maintaining the precision well below 0.15 rad.
In the second part of this study, a systematic comparison was made between two ion fragmentation acquisition modes, namely data-independent acquisition (DIA) and DIA with ion mobility spectrometry (IMS) technology. These two approaches were applied to the analysis of 192 doping agents in urine. Group I included 102 compounds such as stimulants, diuretics, narcotics, and β2-agonists, while Group II contained 90 compounds included steroids, glucocorticoids, and hormone and metabolic modulators. Important method parameters were examined and compared, including the fragmentation, sensitivity, and assignment capability with the minimum occurrence of false positive hits. The results differed between Group I and II in number of detected fragments when exploring the MS/MS spectra. In Group I only 13%, while in the Group II 64% of the substances had a higher number of fragments in DIA-IMS mode vs. DIA. In terms of sensitivity, the performance of the two modes with and without activated IMS dimension was identical for about 50% of the doping agents. The sensitivity was higher without IMS, i.e. in simple DIA mode, for 20-40% of remaining doping agents. Despite this sensitivity reduction with IMS, 82% of compounds from both Groups met the minimum required performance level (MRPL) criteria of the World Anti-Doping Agency (WADA) when the DIA-IMS mode was applied. Automated data processing is important in routine doping analysis. Therefore, processing methods were optimized and evaluated for the prevalence of false peak assignments by analysing the target substances at different concentrations in urine samples. Overall, a significantly higher number of misidentified compounds was observed in Group II, with an almost 2-fold higher number of misidentifications in DIA compared to DIA-IMS. This result highlights the benefit of the IMS dimension to reduce the rate of false positive in screening analysis. The optimized UHPLC-IM-HRMS method was finally applied to the analysis of urine samples from administration studies including nine doping agents from both Groups. However, to limit the number of interferences from the biological matrix, an emphasis is needed on the adequate settings of the data processing method.
- Keywords
- Anti-Doping analysis, Collision cross section, High resolution mass spectrometry, Ion mobility spectrometry, Ultra-high performance liquid chromatography,
- MeSH
- Doping in Sports * MeSH
- Glucocorticoids MeSH
- Ion Mobility Spectrometry * MeSH
- Narcotics MeSH
- Steroids MeSH
- Tandem Mass Spectrometry MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- Glucocorticoids MeSH
- Narcotics MeSH
- Steroids MeSH
Non-invasive health monitoring technologies increasingly attract attention as they allow for continuous, comfortable vital sign monitoring. However, contactless sensing of vital signs using radar systems has significant challenges in accurately extracting physiological information from noisy signals, especially when subjects move freely. This study introduces a novel framework that combines Independent Component Analysis (ICA) and Empirical Wavelet Transform (EWT) to estimate respiratory rate (RR) from radar signals under free-movement conditions. ICA automatically selected physiologically relevant components from the radar signals. Subsequently, the Empirical Wavelet Transform served as an adaptive Multi-Resolution Analysis (MRA) technique, effectively decomposing and reconstructing respiratory signals to improve peak detection accuracy. We evaluated the proposed framework using experimental data from ten subjects performing activities that mimic daily life in a living laboratory environment. A TMSi MOBi8 system recorded the reference RR signals simultaneously. Performance evaluation using Pearson's correlation coefficient revealed a strong correlation (r = 0.94) for the best-performing method. At the same time, the Bland-Altman analysis showed a mean error of -0.41 breaths per minute, demonstrating the ICA-EWT framework's effectiveness in estimating RR in freely moving real-world settings. However, addressing issues related to radar placement and signal interference is suggested to improve the method's accuracy.
- Keywords
- Breathing rate, ICA, MRA, UWB, Vital signs monitoring,
- MeSH
- Algorithms MeSH
- Respiratory Rate * physiology MeSH
- Adult MeSH
- Humans MeSH
- Monitoring, Physiologic methods MeSH
- Signal Processing, Computer-Assisted * MeSH
- Wavelet Analysis * MeSH
- Check Tag
- Adult MeSH
- Humans MeSH
- Male MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Review MeSH
This study investigated whether differences between personality styles in the processing of social stimuli reflect variability in underlying general-purpose or social-specific neurocognitive mechanisms. Sixty-five individuals classified previously into two distinct personality profiles underwent high-density electroencephalography whilst performing tasks that tap into both aspects of cognitive processing - namely, two distinct facets of general-purpose response inhibition (interference resolution and action withholding) during social information processing. To determine the stage of processing at which personality differences manifest, we assessed event-related components associated with the early visual discrimination of social stimuli (N170, N190) and later more general conflict-related processes (N2, P3). Although a performance index of interference resolution was comparable between the personality profiles, differences were detected in action withholding. Specifically, individuals expressing a wider repertoire of personality styles and more adaptive emotion regulation performed significantly better at withholding inappropriate actions to neutral faces presented in emotional contexts compared with those exhibiting stronger preferences for fewer and less adaptive personality styles and more ruminative affective tendencies. At the neurophysiological level, however, difference between the profiles was observed in brain responses elicited to the same stimuli within the N170. These results indicate that neural processes related to early visual discrimination might contribute to differences in the suppression of inappropriate responses towards social stimuli in populations with different personality dispositions.
- Keywords
- action orientation, action withholding, interference resolution, personality, response inhibition, social cognition,
- MeSH
- Electroencephalography * methods MeSH
- Emotions physiology MeSH
- Evoked Potentials * physiology MeSH
- Cognition physiology MeSH
- Humans MeSH
- Personality MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
A method for simultaneous determination of cadmium and iron in cereal flakes using high-resolution continuum source graphite furnace atomic absorption spectrometry is presented. Sample digest is introduced into the graphite furnace together with Pd/Mg(NO3)2 modifier. The primary absorption line of cadmium and adjacent secondary line of iron are used for the determination. Atomization is performed as a two-step process in order to meet ideal conditions for both elements. Interference produced by molecular absorption of PO molecular bands is suppressed by correction model using least squares background correction. Using the proposed method, levels of cadmium and iron were determined in different kinds of cereal flakes, where both elements are of great interest. Working range (0.01-2 μg L-1 for Cd and 10-500 μg L-1 for Fe) was suitable for the determination of analytes in samples. The method is fast, robust, and may be routinely used routinely in the analysis of foodstuffs.
- Keywords
- Cadmium, Cereals, HR CS GFAAS, Iron, Simultaneous determination,
- MeSH
- Food Analysis methods MeSH
- Graphite chemistry MeSH
- Edible Grain chemistry MeSH
- Cadmium analysis MeSH
- Spectrophotometry, Atomic methods MeSH
- Iron analysis MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- Graphite MeSH
- Cadmium MeSH
- Iron MeSH
