Resolution Values Research Articles

The Climate Data for Adaptation and Vulnerability Assessments and the Spatial Interactions Downscaling Method

This study presents the spatial interactions downscaling (SPID) method and introduces the climate data for adaptation and vulnerability assessments (ClimAVA) dataset. SPID employs random forest models to capture the relationship between spatial patterns at global circulation model (GCM) resolution and fine-resolution pixel values. In summary, a random forest model is trained for each fine spatial resolution pixel of the reference data as the predictand, and nine pixels from the spatially resampled (coarser) version of the reference data at the GCM’s resolutions as predictors. Models are then utilized to downscale the bias-corrected GCM data. The ClimAVA-SW dataset offers a high-resolution (4 km), bias-corrected, downscaled future climate projection derived from seventeen CMIP6 GCMs. It includes three variables (daily precipitation, minimum and maximum temperature) for three shared socioeconomic pathways (SSP245, SSP370, SSP585) across the U.S. Southwest region. The ClimAVA dataset sets itself apart with the SPID method’s capacity to provide remarkable climate realism, high physical plausibility of change, and excellent representation of extreme events while maintaining user-friendliness and requiring relatively low computational resources.

Spatial resolution limit for a solid immersion lens

The solid immersion (SI) effect is widely used to increase the spatial resolution of optical focusing systems and even overcome the Abbe diffraction limit. Resolution enhancement offered by a SI lens is mostly a function of its geometry and refractive index nSI. While SI lenses are relatively well understood, the scaling of the resolution enhancement by such lenses is still a subject of debate, with some works reporting ≃nSI and ≃nSI2 dependencies for the hemispherical and hyperhemispherical SI lens configurations, respectively. In this paper, we offer a general argument for a resolution limit for SI optics and, then, verify it via the numerical analysis of the hemispherical and hyperhemispherical silicon SI lenses designed for the terahertz (THz) range. In fact, we find that there is no contradiction in the reported resolution enhancements ≃nSI and ≃nSI2; however, they happen in different operation regimes. We then demonstrate that the resolution values reported for the different SI lens arrangements in the visible (VIS), near-, and middle-infrared (NIR and MIR), as well as THz bands obey the derived limit. Our findings will be useful for the further design and applications of SI optics.

Device response principles and the impact on energy resolution of epitaxial quantum dot scintillators with monolithic photodetector integration

Epitaxial quantum dot (QD) scintillator crystals with picosecond-scale timing and high light yield have been created for medical imaging, high energy physics and national security applications. Monolithic photodetector (PD) integration enables the sensing of photons generated within the waveguiding crystal and allows a wide range of scintillator-photodetector coupling geometries. Until recently, these doubly novel devices have suffered from complex, high variance responses to monoenergetic sources which significantly reduces their precision and accuracy. The principles governing the overall device response have now been discerned and embodied by an expression derived within a geometrical optics framework which considers optical properties, surface roughness and photodetector coupling geometry. Response variation due to these factors was sufficiently reduced to obtain material-related energy resolution values of 2.4% with alpha particles. These findings place energy resolution alongside luminescence timescale, photon yield, and radiation hardness as outstanding properties of these engineered materials.

Evaluation of super resolution technology for digestive endoscopic images

ObjectThis study aims to evaluate the value of super resolution (SR) technology in augmenting the quality of digestive endoscopic images. MethodsIn the retrospective study, we employed two advanced SR models, i.e., SwimIR and ESRGAN. Two discrete datasets were utilized, with training conducted using the dataset of the First Affiliated Hospital of Soochow University (12,212 high-resolution images) and evaluation conducted using the HyperKvasir dataset (2,566 low-resolution images). Furthermore, an assessment of the impact of enhanced low-resolution images was conducted using a 5-point Likert scale from the perspectives of endoscopists. Finally, two endoscopic image classification tasks were employed to evaluate the effect of SR technology on computer vision (CV). ResultsSwinIR demonstrated superior performance, which achieved a PSNR of 32.60, an SSIM of 0.90, and a VIF of 0.47 in test set. 90 % of endoscopists supported that SR preprocessing moderately ameliorated the readability of endoscopic images. For CV, enhanced images bolstered the performance of convolutional neural networks, whether in the classification task of Barrett's esophagus (improved F1-score: 0.04) or Mayo Endoscopy Score (improved F1-score: 0.04). ConclusionsSR technology demonstrates the capacity to produce high-resolution endoscopic images. The approach enhanced clinical readability and CV models’ performance of low-resolution endoscopic images.

Effect of Different Fluorescence Iabelling Methods of the Actin Cytoskeleton for Storm Application

The Abbe limit was a major challenge in optical microscopy, making it difficult to observe microscopic biological structures. However, the development of STORM, a new fluorescence localization microscopy technique, has enabled much higher resolution imaging by causing dye molecules to blink under laser light. Advances in computational analysis have further improved image processing and resolution, leading to clearer observations and a better understanding of biological structures. Actin, a common protein in eukaryotic cells, forms F-actin, a filament involved in essential processes like cell division, migration, and muscle contraction. Fluorescence labeling is crucial for visualizing F-actin and other cellular structures, allowing scientists to study these important processes. This project explored two methods to visualize actin structures in Hela cells: phalloidin labeling with Alexa-647 dye and DNA-PAINT using GFP. ThunderSTORM analysis produced normalized images for both methods, and resolution values were calculated using FRC. The results indicated that phalloidin labeling provided higher resolution but lower-quality images, while DNA-PAINT with GFP offered better-quality images but with lower resolution.

SP8.11 - Conflict Resolution in Surgery

Abstract Aim In our study, we dive into perspectives gathered from academic and public investigations, shedding light on how patient safety is at risk when communication and professional behaviours crumble within surgical teams. Despite clear evidence, current educational paths for both undergraduates and postgraduates prioritise surgical knowledge and skills, sidelining the crucial aspects of effective teamwork and conflict resolution. The increasing diversity in the surgical workforce, paired with a spectrum of personalities, emphasises the urgency of evaluating the evidence base on how interpersonal conflict impacts and exploring effective interventions. This evaluation is pivotal for shaping the direction of future curricula. Methods We took a systematic approach, exploring databases using keywords like "conflict resolution," "surgery," and "healthcare professionals," and related terms. Following PRISMA guidelines, we analysed identified studies, resolving any discrepancies through collaborative discussions among reviewers. Results Sixty-three studies reveal the adverse effects of interpersonal conflict on healthcare professionals (HCPs), leading to stress, burnout, job dissatisfaction, and compromising team effectiveness and patient safety. Conflict causes were categorised into systemic and interpersonal factors, with resolution interventions focusing on improving communication skills, organising team-building workshops, and facilitating debriefing sessions. Despite recognising the value of conflict resolution, variations in strategies were noted across different surgical specialties. Conclusion This systematic review underlines interpersonal conflict within surgical teams as a significant threat to patient safety and the well-being of healthcare professionals. The literature exposes strategic diversity in reported educational interventions, advocating for the integration of formalised training in teamworking and conflict resolution—an often overlooked yet vital component in surgical curricula.

Preparation of DNA nanoflower-modified capillary silica monoliths for chiral separation.

Innovative chiral capillary silica monoliths (CSMs) were developed based on DNA nanoflowers (DNFs). Baseline separation of enantiomers such as atenolol, tyrosine, histidine, and nefopam was achieved by using DNF-modified CSMs, and the obtained resolution value was higher than 1.78. To further explore the effect of DNFs on enantioseparation, different types of chiral columns including DNA strand containing the complementary sequence of the template (DCT)-modified CSMs, DNF2-modified CSMs, and DNF3-modified CSMs were prepared as well. It was observed that DNF-modified CSMs displayed better chiral separation ability compared with DCT-based columns. The intra-day and inter-day repeatability of model analytes' retention time and resolution kept desirable relative standard deviation values of less than 8.28%. DNF2/DNF3-modified CSMs were able to achieve baseline separation of atenolol, propranolol, 2'-deoxyadenosine, and nefopam enantiomers. Molecular docking simulations were performed to investigate enantioselectivity mechanisms of DNA sequences for enantiomers. To indicate the successful construction of DNFs and DNF-modified CSMs, various charaterization approaches including scanning electron microscopy, agarose gel electrophoresis, dynamic light scattering analysis, electroosmotic flow, and Fourier-transform infrared spectroscopy were utilized. Moreover, the enantioseparation performance of DNF-modified CSMs was characterized in terms of sample volume, applied voltage, and buffer concentration. This work paves the way to applying DNF-based capillary electrochromatography microsystems for chiral separation.

Nationwide prospective audit for the evaluation of appendicitis risk prediction models in adults: right iliac fossa treatment (RIFT)-Turkey.

Appendicitis is the most prevalent surgical emergency. The negative appendicectomy rate and diagnostic uncertainty are important concerns. This study aimed to assess the effectiveness of current appendicitis risk prediction models in patients with acute right iliac fossa pain. A nationwide prospective observational study was conducted, including all consecutive adult patients who presented with right iliac fossa pain. Diagnostic, clinical and negative appendicectomy rate data were recorded. The Alvarado score, Appendicitis Inflammatory Response (AIR), Raja Isteri Pengiran Anak Saleha Appendicitis (RIPASA) and Adult Appendicitis Score systems were calculated with collected data to classify patients into risk categories. Diagnostic value and categorization performance were evaluated, with use of risk category-based metrics including 'true positive rate' (percentage of appendicitis patients in the highest risk category), 'failure rate' (percentage of patients with appendicitis in the lowest risk category) and 'categorization resolution' (true positive rate/failure rate). A total of 3358 patients from 84 centres were included. Female patients were less likely to undergo surgery than men (71.5% versus 82.5% respectively; relative risk 0.866, 95% c.i. 0.834 to 0.901, P < 0.001); with a three-fold higher negative appendicectomy rate (11.3% versus 4.1% respectively; relative risk 2.744, 95% c.i. 2.047 to 3.677, P < 0.001). Ultrasonography was utilized in 56.8% and computed tomography in 75.2% of all patients. The Adult Appendicitis Score had the best diagnostic performance for the whole population; however, only RIPASA was significant in men. All scoring systems were successful in females patients, but Adult Appendicitis Score had the highest area under the receiver operating characteristic curve value. The RIPASA and the Adult Appendicitis Score had the best categorization resolution values, complemented by their exceedingly low failure rates in both male and female patients. Alvarado and AIR had extremely high failure rates in men. The negative appendicectomy rate was low overall, but women had an almost three-fold higher negative appendicectomy rate despite lower likelihood to undergo surgery. The overuse of imaging tests, best exemplified by the 75.2% frequency of patients undergoing computed tomography, may lead to increased costs. Risk-scoring systems such as RIPASA and Adult Appendicitis Score appear to be superior to Alvarado and AIR.

How does a dynamic surface roughness affect snowpack modeling?

The SNOWPACK model is a cryosphere model which incorporates several environmental model parameters, one of which being the aerodynamic roughness length (z0). The z0 is considered a static parameter, however, research has shown that the z0 of the surface is variable due to the changing nature of the snowpack surface throughout the winter season. This study highlights the sensitivity of the z0 within the SNOWPACK model based on the outputs of sublimation, SWE, and sensible heat. The z0 values were calculated in two ways, anemometrically (z0-A), using a wind profile, and geometrically (z0-G), measuring surface geometry. Calculated z0-A values were between 1.03 × 10−6 to 0.12 m. The z0-G values were calculated from a terrestrial lidar scan using various resolution values of post-process resolutions. These resolutions of 0.01, 0.1, and 1 m resulted in z0-G values of 0.26, 0.08, and 0.01 m, respectively. Therefore, as the resolution coarsened, the z0-G values decreased. Lastly, these calculated z0-G values, a variable run, using weekly measured z0-G values, and 0.002 (SNOWPACK default), 0.02, and 0.2 m values were incorporated into the SNOWPACK model. When applied, cumulative sublimation, SWE, and sensible heat outputs varied by 131%, −71%, and −49%, when compared to the default z0 value used within the model.

Kintex ultrascale’s multi-segment digital tapped delay lines with controlled characteristics for precise time-to-digital conversion

This paper describes an efficient method of designing and implementing in FPGA devices complex tapped delay lines (CTDL) with pico and sub-picosecond resolution. Achieving a higher resolution and better linearity is possible by appropriate selection of single time coding tapped delay lines (TDL) involved in creation of CDTL. The proposed TDL selection algorithm significantly optimizes the size of the device’s logical resources required to implement CDTL with assumed parameters and provides a proper selection scenario. Ultimately, the presented solution allows to create CTDLs with different user-defined configurations based on a fixed set of available logical resources. Therefore, it is particularly recommended for prototyping in smaller FPGA devices. In this work, we investigate how the order of line selection influences the increase of the multiple time coding lines resolution. Furthermore, we determine the relation between the equivalent resolution value and the number of TDLs involved. Obtained results allow to estimate the upper limit of resolution that can be achieved using a given technology. In addition, the ranges of resolutions achievable with a fixed number of lines is also examined. The presented research results have been performed on a Kintex UltraScale FPGA chip, manufactured by Xilinx in the 20-nm CMOS process.

Design, Modeling, and Testing of a Long-Stroke Fast Tool Servo Based on Corrugated Flexure Units.

To further enhance the performance of the fast tool servo (FTS) system in terms of stroke, load capacity, and application area, this paper proposes a novel fast tool servo device driven by a voice coil motor (VCM), based on a three-segment uniform corrugated flexure (CF) guiding mechanism, with a large stroke, high accuracy, and high dynamics. To describe the unified static characteristics of such device, the compliance matrix method is applied to establish its model, where the influence of CF beam structural parameters on the FTS device is investigated in detail. Furthermore, resolution and positioning accuracy tests are conducted to validate the features of the system. The testing results indicate that the maximum stroke of the FTS device is up to 3.5 mm and the positioning resolution values are 3.6 μm and 2.4 μm for positive and negative stroke, respectively, which further verifies the device's effectiveness and promising application prospect in ultra-precision microstructure machining.

A new data complexity measure for multi-class imbalanced classification tasks

The skewed class distribution and data complexity may severely affect the imbalanced classification results. The cost of classification can be significantly reduced if these data complexity are measured and pre-processed prior to training, particularly when dealing with large-scale and high-dimensional datasets. Although many methods have been proposed to evaluate data complexity, most of them fail to fully consider the interaction among different data characteristics, or the connection between class imbalance and these characteristics, thus posing a serious challenge to effectively evaluate the difficulty of classification. This paper presents a new data complexity measure MFII (multi-factor imbalance index), which measures the combined effects of the skewed class distribution and data characteristics on classification difficulty. In particular, it further comprehensively investigates the impact of overlap size, confusion degree, and sub-cluster structure. VoR (value of resolution) and DoC (degree of consistency) are also proposed to evaluate the resolution and interpretability of complexity measures. The experimental results demonstrate that MFII has lower VoR and a stronger correlation with classification metrics, which indicates that MFII can more accurately evaluate the difficulty of multi-class imbalanced classification tasks.

Optimization and experimental validation of deuterium-tritium neutron monoenergetics for diamond detector testing

Diamond detectors are excellent tools for measuring deuterium-tritium (D-T) neutron energy spectra. It has great potential for application in the field of magnetic confinement fusion. However, the current experimental values of the energy resolution of diamond detectors are much lower than the theoretical estimates. The purpose of this study is to find a method for experimental optimization. For this purpose, the D-T neutron energy distribution of the accelerator is theoretically analyzed and simulated. A method to increase the deuteron energy to obtain a better monoenergetic neutron source is proposed. This strategy was validated experimentally. The energy resolution of diamond for D-T neutrons achieves 1.21%, a Full Width at Half Maximum of 93 keV at 7.65 MeV. It is the highest resolution recorded to date. These results demonstrate the feasibility of the optimization method.

Direct Enantiomer Differentiation of Drugs and Drug-Like Compounds via Noncovalent Copper-Amino Acid Complexation and Ion Mobility-Mass Spectrometry.

Drug enantiomers can possess vastly different pharmacological properties, yet they are identical in their chemical composition and structural connectivity. Thus, resolving enantiomers poses a great challenge in the field of separation science. Enantiomer separations necessitate interaction of the analyte with a chiral environment─in mass spectrometry-based analysis, a common approach is through a three-point interaction with a chiral selector commonly introduced during sample preparation. In select cases, the structural difference imparted through noncovalent complexation results in enantiomer-specific structural differences, facilitating measurement using a structurally selective analytical technique such as ion mobility-mass spectrometry (IM-MS). In this work, we investigate the direct IM-MS differentiation of chiral drug compounds using mononuclear copper complexes incorporating an amino acid chiral selector. A panel of 20 chiral drugs and drug-like compounds were investigated for separation, and four l-amino acids (l-histidine, l-tryptophan, l-proline, and l-tyrosine) were evaluated as chiral selectors (CS) to provide the chiral environment necessary for differentiation. Enantiomer differentiation was achieved for four chiral molecule pairs (R/S-thalidomide, R/S-baclofen, R/S-metoprolol, and d/l-panthenol) with two-peak resolution (Rp-p) values ranging from 0.7 (>10% valley) to 1.5 (baseline separation). Calibration curves relating IM peak areas to enantiomeric concentrations enabled enantiomeric excess quantitation of racemic thalidomide and metoprolol with residuals of 5.7 and 2.5%, respectively. Theoretical models suggest that CuII and l-histidine complexation around the analyte chiral center is important for gas-phase stereoselectivity. This study demonstrates the potential of combining enantioselective noncovalent copper complexation with structurally selective IM-MS for differentiating chiral drugs and drug-like compounds.

Association between ST-Segment Resolution Following Thrombolysis and Reperfusion of Infarct Related Artery in Coronary Angiogram in Patients with ST-Segment Elevation Myocardial Infarction

Background: ST-segment elevation myocardial infarction (STEMI) is the most critical form of acute coronary syndrome as having the worst overall prognosis. Following thrombolysis, if it is possible to reliably predict about the reperfusion status by means of a non-invasive, readily available tool like ECG, it will help the clinicians to determine the quality of reperfusion and select the next strategy of management. The aim of the study was to assess angiographic findings of TIMI flow in infarct related artery (IRA), compared to the ranges of ST-segment resolution, and determine their association to predict reperfusion in IRA. Methods: Thiscross-sectional observational study was conducted in the department of Cardiology at National Institute of Cardiovascular Diseases (NICVD), Dhaka, for 12-months following ethical approval. A total of 116 adult patients with acute STEMI who underwent thrombolysis with streptokinase were enrolled by convenient sampling method after taking written informed consent. The percent resolution of ST-segment deviation from baseline to 60 minutes following thrombolysis was compared with angiographic IRA TIMI flow grade in index hospitalization. Detailed history, thorough clinical examination and necessary investigations were carried out in each patient and recorded in predesigned structured questionnaire. Data were analyzed by SPSS 26.0. Results: The mean age of the patients was 50.8 ± 8.8 years with male predominance (77.6%). Among all, 45.7% had &gt;70% ST resolution followed by 29.3% had 30-70% and 25% had &lt;30% ST resolution. Regarding TIMI grade flow, 59.1% had grade-3, 22.7% had grade-2 and 18.2% had grade 0 or 1. TIMI grade flow significantly increased with the increased ST-segment resolution. A cut off value of ST-segment resolution ≥57.5% (AUC=0.771, 95% CI=0.684-0.858, p&lt;0.001) in the prediction of TIMI grade flow 3 showed 67.69% sensitivity, 66.67% specificity, 74.58% PPV, 58.82% NPV and 67.27% accuracy. Multivariate logistic regression shows that timing of thrombolysis, &gt;70% ST resolution showed higher odds ratio and &gt;70% ST resolution showed statistically significant p-value for predicting TIMI grade flow 2 or 3. Conclusion: ST-segment resolution in electrocardiogram following thrombolysis has significant positive association with TIMI flow of infarct related artery in coronary angiogram. However, further larger study is recommended.

Implementasi Multikultural Siswa Dalam Pembelajaran Pendidikan Agama Islam di Sekolah Dasar Negeri Cipayung 04

This study aims to analyze the implementation of Islamic religious education with a multicultural perspective in elementary schools. The research was conducted at Cipayung 04 Public Elementary School. The research method used a qualitative case study. Sources of data teachers, principals, and students. The research instrument used interviews, observation and documentation. Data analysis techniques include: data collection, data reduction, data verification and data display. The results of the multicultural-based implementation of Islamic religious education research through: 1) The new student admission policy does not discriminate between ethnicity, race and religion; 2) Implementation of learning upholds the values ​​of mutual respect, openness, compassion, conflict resolution and reconciliation and violence; 3) Realizing tolerance in religious life in life between all members of the community in daily life in the school environment. Multicultural values ​​are a process of acquiring knowledge, developing attitudes and behavior to live in mutual respect, tolerance, full of peace, mutual assistance and non-violence. Islamic religious education is education that focuses more on improving the mental attitude that is manifested in actions, both for the needs of oneself and others, both theoretically and practically. This research focuses on three studies, firstly all forms of multicultural values ​​in learning Islamic religious education at Cipayung 04 Public Elementary School. So it is related to efforts regarding multicultural-based learning so far because the school does not have multiculturalism, the school places more emphasis on character education. One of education, cultural education can be in the form of mutual cooperation, mutual respect, responsibility, discipline. So character education is very important to achieve quality education for students. If the character has been formed early on in order to make quality and qualified students. And in practice learning is also more respectful and tolerant among peers, in learning it emphasizes Pancasila values ​​in respecting diversity.

The Binding Capacity of the Lead Phytochemical Molecule to Cancer Cell Target Proteins and its Potential Anticancer Properties with Respect to Standard Drugs

Molecular docking is an important tool for connecting molecular biological structure to computer-aided drug design. The purpose of this blind docking experiment is to compare the binding energies of these three drugs and to predict the most likely binding poses of a ligand with a known three dimensional structure of a protein. To substantiate our previous in vitro study findings, an in silico model was chosen to compare the binding properties of the three drugs. The work is entirely bioinformatics in nature. Blind docking was accomplished with the help of free software/(s). A comparison was made among the three drgus, used primarily in cancer treatment, namely, anastrazole, capecitabine and quercetin. In our in vitro study, these three drugs were extremely effective. CB dock-2 to blind dock, SwissTargetPrediction to choose the targets, PubChem and Protein Data Base to obtain 3D structures of ligand and target respectively were used. Absorption, Distribution, Metabolism, and Excretion (ADME) from SwissADME, drug likeness from MolSoft L.L.C. software, and Liponski’s rule was used to check the “Rule of five (RO5)”. The crystallographic structures have resolution values ranging from 1 Å to 3 Å. Lipinski’s rule of five, Swiss ADME and drug likeness were used to compare the three drugs. For all of the targets studied, quecetin appeared to have the highest AutoDock vina scores. To summarize the current findings and publicly available data, quercetin is chemoprotective and radioprotective to healthy/ normal cells and it can be used during cancer treatment.

Clinical boundary conditions for propagation-based X-ray phase contrast imaging: from bio-sample models targeting to clinical applications.

Typical propagation-based X-ray phase contrast imaging (PB-PCI) experiments using polyenergetic sources are tested in very ideal conditions: low-energy spectrum (mainly characteristic X-rays), small thickness and homogeneous materials considered weakly absorbing objects, large object-to-detector distance, long exposure times and non-clinical detector. Explore PB-PCI features using boundary conditions imposed by a low power polychromatic X-ray source (X-ray spectrum without characteristic X-rays), thick and heterogenous materials and a small area imaging detector with high low-detection radiation threshold, elements commonly found in a clinical scenario. A PB-PCI setup implemented using a microfocus X-ray source and a dental imaging detector was characterized in terms of different spectra and geometric parameters on the acquired images. Test phantoms containing fibers and homogeneous materials with close attenuation characteristics and animal bone and mixed soft tissues (bio-sample models) were analyzed. Contrast to Noise Ratio (CNR), system spatial resolution and Kerma values were obtained for all images. Phase contrast images showed CNR up to 15% higher than conventional contact images. Moreover, it is better seen when large magnifications (>3) and object-to-detector distances (>13 cm) were used. The influence of the spectrum was not appreciable due to the low efficiency of the detector (thin scintillator screen) at high energies. Despite the clinical boundary condition used in this work, regarding the X-ray spectrum, thick samples, and detection system, it was possible to acquire phase contrast images of biological samples.

A Performance Comparison of 3D Survey Instruments for Their Application in the Cultural Heritage Field.

Thanks to the recent development of innovative instruments and software with high accuracy and resolution, 3D modelling provides useful insights in several sectors (from industrial metrology to cultural heritage). Moreover, the 3D reconstruction of objects of artistic interest is becoming mandatory, not only because of the risks to which works of art are increasingly exposed (e.g., wars and climatic disasters) but also because of the leading role that the virtual fruition of art is taking. In this work, we compared the performance of four 3D instruments based on different working principles and techniques (laser micro-profilometry, structured-light topography and the phase-shifting method) by measuring four samples of different sizes, dimensions and surface characteristics. We aimed to assess the capabilities and limitations of these instruments to verify their accuracy and the technical specifications given in the suppliers' data sheets. To this end, we calculated the point densities and extracted several profiles from the models to evaluate both their lateral (XY) and axial (Z) resolution. A comparison between the nominal resolution values and those calculated on samples representative of cultural artefacts was used to predict the performance of the instruments in real case studies. Overall, the purpose of this comparison is to provide a quantitative assessment of the performance of the instruments that allows for their correct application to works of art according to their specific characteristics.

Analytical quality by design-based development of a capillary electrophoresis method for Omeprazole impurity profiling

Omeprazole (OME) is a proton pump inhibitor used to treat gastroesophageal reflux disease associated conditions. The current study presents an Analytical Quality by Design-based approach for the development of a CE method for OME impurity profiling. The scouting experiments suggested the selection of solvent modified Micellar ElectroKinetic Chromatography operative mode using a pseudostationary phase composed of sodium dodecyl sulfate (SDS) micelles and n-butanol as organic modifier in borate buffer. A symmetric three-level screening matrix 37//16 was used to evaluate the effect of Critical Method Parameters, including Background Electrolyte composition and instrumental settings, on Critical Method Attributes (critical resolution values, OME peak width and analysis time). The analytical procedure was optimized using Response Surface Methodology through a Central Composite Orthogonal Design. Risk of failure maps made it possible to define the Method Operable Design Region, within which the following optimized conditions were selected: 72 mM borate buffer pH 10.0, 96 mM SDS, 1.45 %v/v n-butanol, capillary temperature 21 °C, applied voltage 25 kV. The method was validated according to ICH guidelines and robustness was evaluated using a Plackett-Burman design. The developed procedure enables the simultaneous determination of OME and seven related impurities, and has been successfully applied to the analysis of pharmaceutical formulations.