Potential Step Research Articles

Innovative Molecularly Imprinted Electrochemical Sensor for Selective Nanomolar Detection of the Anti-COVID-19 Medication Molnupiravir

For the first time, a green ecofriendly approach is applied, to develop a molecularly imprinted polymer (MIP) electrochemical for the assay of the oral anti-viral molnupiravir (MLN) in various matrices as confirmed by referring to analytical eco-scale, green analytical procedure index (GAPI), Raynie and Driver, analytical greenness metric (AGREE), and national environmental index (NEMI). AuNPs were chronoamperometry deposited on the glassy carbon electrode surface (GCE) using 0.01 gm ml−1 gold solution (HAuCl4.3H2O) in 0.5 M H2SO4 at a constant potential of −0.4 V for 60 s. Then, the MIP was created by electropolymerizing OPDA on the surface of AuNPs GCE using cyclic voltammetry in the potential range between −0.5 and +1 V for 15 cycles (scan rate: 50 mV.s−1). To optimize the sensor’s performance, factors such as number of electropolymerization cycles, template: monomer ratio, binding and rebinding time, pH of rebinding buffer, extraction solvent, deposition time of Au nanoparticles, order of deposition on the electrode; surface, as well as differential pulse voltammetry parameters including accumulation potential and time, and potential step, were all investigated. The detection limit was set at 0.00098 ng ml−1 (3 × 10−12M) and the linearity range of MLN was between 0.033 ng ml−1 and 164 ng ml−1 (1 × 10−10–5 × 10−7 M). The MIP sensor was employed for MLN determination in its pharmaceutical product (capsules), spiked human plasma, and human urine samples with mean recovery % ± mean relative standard deviation (RSD) (99.82% ± 0.53), (99.88% ± 0.62), and (97.90% ± 0.70), respectively. The investigated sensor provided good reproducibility, repeatability, and durability. Acceptable selectivity regarding MLN when mixed with structurally comparable compounds was proved with mean recovery % ± mean RSD (97.10% ± 0.03). Additionally, when molnupiravir was exposed to oxidative, hydrolytic, and thermal stress conditions, good results in stability-indicating studies served as an indicator of sensor selectivity. The developed electrode is coupled with a portable potentiostat, making it a promising point-of-care diagnostic platform for on-site measurements.

Bayesian modeling framework for optimizing pre-hospital stroke triage decisions

Ischemic stroke is responsible for significant morbidity and mortality in the United States and worldwide. Stroke treatment optimization requires emergency medical personnel to make rapid triage decisions concerning destination hospitals that may differ in their ability to provide highly time-sensitive pharmaceutical and surgical interventions. These decisions are particularly crucial in rural areas, where transport decisions can have a large impact on treatment times – often involving a trade-off between delay in pharmaceutical therapy or a delay in endovascular thrombectomy. In this work, we explore a Bayesian modeling framework to address this decision-making process, showing how these techniques may be used to fully account for diagnostic and therapeutic uncertainty. We demonstrate how these techniques can contextualize triage decision at a fine-grained spatial scale. We further show the application of this modeling approach in the US State of Iowa, using data from the Virtual International Stroke Trials Archive (VISTA), and describe potential next steps for improved triage. ABBREVIATION LVO: large vessel occlusion; non-LVO, non-large vessel occlusion; IVT: intravenous tissue plasminogen activator; EVT: endovascular thrombectomy; CSC: comprehensive stroke centers; PSC: primary stroke centers; DS: drip and ship; MS, mothership; EMS: Emergency Medical Service; BGLM: Bayesian Generalized Linear Model; BGAM: Bayesian Generalized Additive Model; BART: Bayesian Additive Regression Trees; VISTA: Virtual International Stroke Trials Archive; NIHSS: National Institute of Health Stroke Severity Scale; ASPECTS: Alberta Stroke Programme Early CT Score; mRS, modified Rankin score; ROCAUC: Area under the receiver operating characteristic curve; ELPD: Expected Log pointwise Predictive Density; SE: Standard Error; ICA: Internal Carotid Artery; M1: Middle Cerebral Artery segment 1; M2: Middle Cerebral Artery segment 2; TIA: Transient Ischemic Attack; Cr-I: Credible Intervals; LKW: Last Known Well

Mentorship literature in counselor education and supervision programs: implications and recommendations for counselor educators

ABSTRACT The present article examines current literature on mentorship for counselor education and supervision (CES) doctoral students, and how current CES mentoring practices impact doctoral students’ personal and professional growth in alignment with accrediting body standards. Findings from the literature highlight the purpose, benefits, and potential barriers to establishing successful mentorship for CES doctoral students. Conceptual frameworks and departmental initiatives in building and infusing a culture of mentorship are explored. Implications and potential action steps for counselor educators are provided.

Disordering of Rh(111) single crystalline electrode surface in O2 saturated acid

The Rh(111) electrode shows superior oxygen reduction reaction (ORR) activity to Ir(111), contradicting the predicted trend based on the volcano plot. To unveil the origin for this, we investigate the interfacial structures of Rh(111) single crystalline electrode in 0.1 M HClO4 and 0.5 M H2SO4 solutions using cyclic voltammetry and potential step chronoamperometry under a hanging meniscus rotating disk electrode configuration. Our results reveal that i) in N2 saturated solution even at a potential below 0.20 V, oxygen-containing species adsorbates can be formed on the Rh(111) surface probably generated by oxidation of water; ii) Even under mild conditions, multiple cycles and current transients in O2 saturated solution at potentials where ORR taking place can cause significant surface disordering; iii) The disordering of the Rh(111) electrode induced by ORR exhibits similar base cyclic voltammograms to those of vicinal Rh(hkl) such as Rh(553) and Rh(332) etc., depending on the potentials applied during ORR, which, in turn, enhances the ORR activity in both 0.1 M HClO4 and 0.5 M H2SO4. These new findings provide valuable insights into the structure-performance relationship of ORR.

An omics-based characterization of Wolfiporia cocos reveals three CYP450 members involved in the biosynthetic pathway of pachymic acid

Wolfiporia cocos is a medicinal mushroom used in China. It biosynthesizes pachymic acid (PA), a main therapeutic triterpene associated with therapies. Nowadays, the unknown PA biosynthesis leads to difficulties in increasing its content in W. cocos. Herein, we report sequencing, assembling, and characterization of the genome and several transcriptomes of W. cocos. Sequence mining determined candidate genes that encode lanosterol synthase, sterol O-acyltransferase, and sterol C-24 methyltransferase likely involved in the steps from lanosterol to PA. Gene cluster analysis identified four CYP450 cDNAs likely involved in the biosynthesis of PA, namely WcCYP64-1, WcCYP64-2, WcCYP52, and WcCYP_FUM15, which were subjected to both overexpression and silencing in mycelia. The overexpression of each of WcCYP64-1, WcCYP52 and WcCYP_FUM15 increased the content of PA, 16α-hydroxytrametenolic acid, eburicoic acid, and tumulosic acid, while the silencing of each gene either significantly or slightly decreased the contents of these four compounds, indicating their involvement in the PA biosynthesis. In addition, different temperatures affected the expression of these genes and the formation of PA. By contrast, the overexpression and silencing of WcCYP64-2 did not alter the formation of these compounds. Taken together, these findings determine more potential steps in the biosynthetic pathway of PA for metabolic engineering.

Dynamics of potential‐induced structural changes at the Ag(111)/alkaline interface

AbstractThe dynamics of the structural changes in the electrochemical double layer at the interface between a Ag(111) electrode and 0.1 M KOH electrolyte have been probed using surface X‐ray diffraction measurements. The X‐ray measurements utilised a lock‐in amplifier technique to obtain a time resolution down to the millisecond scale. Two potential step regions were explored in an attempt to separate the dynamics of the reversible adsorption/desorption of hydroxide species (OHad) and the subsequent cation (K+) ordering in the double layer. By probing different positions in reciprocal space, sensitive to different structural changes, the time‐dependent response of the electrode surface was probed and time constants for the different associated processes were obtained.

Ecosystem functioning during biodiversity loss and recovery

Anthropogenic biodiversity loss can impair ecosystem functioning. Human activities are often managed with the aim of reversing biodiversity loss and its associated functional impacts. However, it is currently unknown whether biodiversity–ecosystem function (BEF) relationships observed during biodiversity recovery are the same as those observed during biodiversity loss. This will depend on how species extirpation and recolonisation sequences compare and how different species influence ecosystem functioning. Using data from a marine benthic invertebrate community, we modelled how bioturbation potential – a proxy for benthic ecosystem functioning – changes along biodiversity loss and recovery sequences governed by species' sensitivity to physical disturbance and recolonisation capability, respectively. BEF relationships for biodiversity loss and recovery were largely the same despite species extirpation and recolonisation sequences being different. This held true irrespective of whether populations were assumed to exhibit compensatory responses as species were removed or added. These findings suggest that the functional consequences of local biodiversity loss can be reversed by alleviating its drivers, as different species present at comparable levels of species richness during biodiversity loss and recovery phases have similar functional effects. Empirically verifying and determining the generality of our model‐based results are potential next steps for future research.

Pengembangan Video Pembelajaran Berbasis Literasi Sains Materi Organ Pencernaan Manusia dan Fungsinya Siswa Kelas VB Sekolah Dasar Negeri 58 Sungai Raya

This study aims to analyze the level of validity and practicality of learning videos based on scientific literacy on the material of the human digestive organs and their functions for class V Elementary School. The research method used is research and development (RnD) by adopting the Borg and Gall model with potential and problem steps, data collection, product design, design validation, design revision, product testing, and product revision. Quantitative data were obtained from the results of product assessments by the validator, the results of filling out the practicality questionnaire on videos by teachers and students. Qualitative data were obtained from suggestions or comments by validators, teachers and students. The research instrument is a questionnaire. The validity level of the video is based on the results of assessments by media experts and material experts while the practicality level of the video is based on the results of responses by teachers and students. The results of the validation level of scientific literacy-based learning videos on the material of the human digestive organs and their functions for class V Elementary School by media experts obtained an average of 4.06 in the "valid" category and material experts obtained an average of 3.79 in the "valid" category. The results of the practicality level of scientific literacy-based learning videos on the human digestive organs and their functions for class V Elementary School by teachers obtained an average of 4.48 in the "very practical" category and students obtained an average of 4.31 in the "very practical" category.

#2567 Protein-bound uremic toxins are better removed with short-daily Home Haemodialysis using low dialysate flow rate: randomized clinical trial results

Abstract Background and Aims Short daily home hemodialysis (HDD) with low dialysate flow rate has been shown in recent years as an attractive alternative for portable dialysis home use. Although the effectiveness of the technique for volume control and elimination of small solutes and middle molecules has been demonstrated, data are scarce for the elimination of protein-bound uremic toxins. The aim of this study was to compare the reduction ratios (RRs) of p-cresol sulfate (pCS) and indoxyl sulfate (IS) in the Physidia HHD system with high-volume online-hemodiafiltration (OL-HDF) treatment. Methods In an open, randomized, cross-over, single-center, controlled study, 40 adult chronic HD patients were treated with a 2.5 h-length HD session with low dialysate flow rate with the Physidia HDD system, and a 4 h-length OL-HDF session in post-dilution mode during two successive weeks. During the sessions, pre-HD and post-HD plasma samples were collected and single and weekly RRs of pC and IS were intraindividually compared for the two dialysis types with linear mixed models. Results Whereas single-session RRs of p-CS and IS were similar in both groups, weekly RRs of both protein-bound uremic toxins were significantly higher with the short-daily HDD Physida system than those obtained with OL-HDF (Table 1). Conclusion The short-daily home hemodialysis using low dialysate flow rate with the Physidia system appears to be a potential technologic step ahead in terms of improved protein-bound uremic toxins removal for dialysis patients, and might contribute to a more adequate dialysis therapy than in-center high-volume online-hemodiafiltration (OL-HDF) treatment.

Double Electrode Experiments Reveal the Processes Occurring at PEDOT-Coated Neural Electrode Arrays.

Neural electrodes have recently been developed with surface modifications of conductive polymers, in particular poly(3,4-ethylenedioxythiophene) (PEDOT), and extensively studied for their roles in recording and stimulation, aiming to improve their biocompatibility. In this work, the implications for the design of practical neural sensors are clarified, and systematic procedures for their preparation are reported. In particular, this study introduces the use of in vitro double electrode experiments to mimic the responses of neural electrodes with a focus on signal-recording electrodes modified with PEDOT. Specifically, potential steps on one unmodified electrode in an array are used to identify the responses for PEDOT doped with different anions and compared with that of a bare platinum (Pt) electrode. The response is shown to be related to the rearrangement of ions in solution near the detector electrode resulting from the potential step, with a current transient seen at the detector electrode. A rapid response for PEDOT doped with chloride (ca. 0.04 s) ions was observed and attributed to the fast movement of chloride ions in and out of the polymer film. In contrast, PEDOT doped with poly(styrenesulfonate) (PSS) responds much slower (ca. 2.2 s), and the essential immobility of polyanion constrains the direction of current flow.

Hydrogen infrastructure modeling in macro-energy systems models - Lessons learned, best practices, and potential next steps (workshop insights)

This short communication is based on a workshop on hydrogen network modeling in macro-energy system models discussing the whole hydrogen value chain: production, transmission, storage, and use, as well as the related issues of demand flexibility, alternative fuels of biological origin, and the integration with district heating. It was organized by the Danish research network ENERforsk with leading modelers from academia, industry, and transmission system operators. The workshop collected (1) lessons learned, (2) best practices, and (3) potential next steps. We conclude that no-regret pathways need to consider evolving hydrogen regulation while balancing social aspects with interests driven by green industrial policy. Important and uncertain issues include the repurposing of natural gas networks, considering hydrogen pipeline standards and existing contracts, or the disposal of brine water. As more demand sectors and carbonaceous fuels are included in the models, carbon management, sustainable biomass, and carbon networks become more important. Collecting and incorporating lessons learned, best practices, and potential next steps will help the modeling community and policymakers to develop sound policies.

Decarbonising LNG value chain using carbon capture and storage: why, where, how much and what are the limitations?

As a result of global aspirations to achieve energy transition along with the desire to ensure energy security, energy exporters proposed a series of new ‘carbon-neutral’ products – liquefied natural gas (LNG) and oil. In 2019, a new market was officially born after the first-in-history shipment of carbon-neutral LNG cargo from Shell to Japanese Tokyo Gas. Until 2021, it grew rapidly, however in 2022, announcements about volumes delivered to the customers significantly dropped. In this paper, we will explore the reasons for this dynamic, review perspectives of the carbon-neutral fuels markets, and explore the potential steps that producers and consumers could undertake to achieve global climate targets. We specifically focus on the consequences of implementing carbon capture and storage (CCS) technologies. Based on the data on the world CCS facilities, provided by the International Energy Agency, we conduct preliminary analysis of the capital costs associated with the construction of carbon capture, utilisation, and storage facilities. After that, we apply the cost estimation method (class 5) based on the US Department of Energy Classification, to estimate the costs of using CCS for emissions management in different regions/countries. As a result, the study demonstrates that due to the various economic, geographical and infrastructural limitations, it is more feasible to implement CCS on the producer’s side than on the consumer’s side. We also show what level of CCS implementation within the LNG value chain is economically feasible for different market participants and what the costs are.

Hidden Real Topology and Unusual Magnetoelectric Responses in Two-Dimensional Antiferromagnets.

Recently, the real topology has been attracting widespread interest in two dimensions (2D). Here, based on first-principles calculations and theoretical analysis, the monolayer Cr2Se2O (ML-CrSeO) is revealed as the first material example of a 2D antiferromagnetic (AFM) real Chern insulator (RCI) with topologically protected corner states. Unlike previous RCIs, it is found that the real topology of the ML-CrSeO is rooted in one certain mirror subsystem of the two spin channels, and cannot be directly obtained from all the valence bands in each spin channel as commonly believed. In particular, due to antiferromagnetism, the corner modes in ML-CrSeO exhibit strong corner-contrasted spin polarization, leading to spin-corner coupling (SCC). This SCC enables a direct connection between spin space and real space. Consequently, large and switchable net magnetization can be induced in the ML-CrSeO nanodisk by electrostatic means, such as potential step and in-plane electric field, and the corresponding magnetoelectric responses behave like a sign function, distinguished from that of the conventional multiferroic materials. This work considerably broadens the candidate range of RCI materials, and opens up a new direction for topo-spintronics and 2D AFM materialsresearch.

‘Peace-Loving Countries, Unite!’ British Reception of Soviet Declarations on ‘Collective Security’ at the Turn of 1934

Soviet-German relations were very conducive for both countries after the Rapallo Treaty was concluded in 1922. There were some signs of difficulties during the Great Depression but they did not influence the willingness of Berlin and Moscow to cooperate. After Adolf Hitler came to power, however, the deterioration of bilateral relations of the two countries became apparent. Finally, at the turn of 1934, a wave of official Soviet declarations on starting cooperation with the ‘peace-loving’ capitalist countries against the aggressor within the framework of the collective security system took place. The article’s aim is to explain whether or not the British Cabinet took notice of these speeches and what attention it paid them. It is important to determine how the British diplomats interpreted these declarations and what was the justification for their viewpoints. Previously, London had tried to separate Germany from the USSR. Hence, the question as to the British government’s understanding of the new situation arised as do the potential steps taken on the international scene once German-Soviet cooperation ceased to exist at the end of 1933. The deterioration of Soviet-German relations had the potential to influence British diplomacy, which was devoted to the idea of collective security.

Burnout Phenomenon on Principals: Impact on Behavior and its Mitigation Strategies

Objective: This research was conducted to gain further understanding of the real experiences (life experiences) of private school principals in order to reveal the substantive meaning of the entire process of their experience of the burnout phenomenon through personal interactions with the principals who were the research subjects which were then articulated through a burnout model that explains more about the processes and factors that play a role in the dynamics of the burnout phenomenon that apply specifically to the subject of school principals. Theoretical Framework: Qualitative research conducted using the phenomenological approach. Research validity was obtained through triangulation of data sources and cross perspectives. Research reliability was obtained through data saturation and in-depth-understanding of the subject from the selected informants. Method: 12 school principals that have worked for around 5-17 years are selected through criteria matching for interviews. This research uses narrative analysis of stories obtained from in-depth interviews with research informants. Result and conclusion: This research has presented evidence that although the role of a leader is very important to motivate and improve the performance of the people being led, in fact the same thing also applies vice versa, the more the people being led or managed can be cooperative with the leader, the more positive the performance of a leader, especially for private school principals in Indonesia. On the other hand, educational foundations as the authority to supervise school principals also have a role in creating a conducive situation for school principals to carry out their duties as well as possible. Research Implications: This research point out several potential steps that need to be taken by educational foundations or organizations that manage an educational institution. This is to ensure that anyone who serves as a school principal can play their role appropriately, efficiently, and produce added value to the organization in the long term. Originality/Value: The findings of this research reinforce theories regarding the burnout phenomenon that have existed so far, by enriching and clarifying the understanding of the meaning of the phenomenon by which the burnout phenomenon occurs at the leadership level in education industry nowadays.

Theoretical research on efficient electrocatalysis of CO2 reduction reaction by borophene loaded transition metals

Electrocatalytic conversion of CO2 into chemical or fuel is regarded as a viable approach to attain energy conversion, chemical energy storage and carbon neutrality. Borophene exhibits great potential as an electrocatalyst owing to its exceptional physical and chemical attributes. β12-borophene incorporated transition metal (TM) as single atom catalysts (SACs) have been devised for the electrocatalysis of the carbon dioxide reduction reaction (CO2RR). Through the exploration of the most favorable CO2RR pathway and the comparison of Gibbs free energy (ΔG) during the potential determination step (PDS), the catalyst exhibiting remarkable catalytic activity for CO2RR are chosen. Wherein, the overpotential of Nb-β12 and Ru-β12 produce CO is only 0.02 and 0.03 V. The overpotential of Ru-β12 and Rh-β12 in generation of HCOOH product is only 0.03 and 0.06 V. Additionally, the catalytic performance of Rh-β12 in CO2 reduction to CH3OH and CH4 showcases exceptional performance, with overpotential of 0.65 and 0.79 V. Unexpectedly, the overpotential of Cd-β12 and Mo-β12 are 0.01 and 0.09 V for hydrogen evolution reaction (HER). The research offers invaluable insight for systematic designs and screening of catalysts for the electrochemical CO2RR.

Exploring Impact of Various Operating Parameters on the Specific Capacitance at the Glassy Carbon/H2SO4 Interface: A Comparative Analysis Using Electrochemical Characterization

AbstractThe aim of this study is to investigate the influence of scanning rate, electrolyte concentration, temperature and electrode rotation speed on the capacitance of glassy carbon electrode in sulfuric acid solution using cyclic voltammetry (CV). The results show that they have a significant influence on the capacitance with varying experimental conditions. In addition, the electrochemical impedance spectroscopy (EIS) method was employed to conduct a more thorough analysis of the ways in which hydrodynamic circumstances resulting from a rotating electrode affect the electrode capacity and the charge storage process. Step potential electrochemical spectroscopy (SPECS) was used to identify the various charge storage mechanisms involved. It was shown that the voltammograms measured by the CV method and determined from the SPECS method have a quasi‐rectangular shape, revealing a predominantly capacitive behavior and that capacitance decreases with increasing scanning rate. Furthermore, both methods confirm that the contribution of the diffusion process is the main factor influencing the charge storage mechanism when the sweep rate is taken into account. However, the SPECS approach provides more accurate and detailed information regarding the kinetic characteristics of the electrode.

Generation of 'semi-guided' cortical organoids with complex neural oscillations.

Temporal development of neural electrophysiology follows genetic programming, similar to cellular maturation and organization during development. The emergent properties of this electrophysiological development, namely neural oscillations, can be used to characterize brain development. Recently, we utilized the innate programming encoded in the human genome to generate functionally mature cortical organoids. In brief, stem cells are suspended in culture via continuous shaking and naturally aggregate into embryoid bodies before being exposed to media formulations for neural induction, differentiation and maturation. The specific culture format, media composition and duration of exposure to these media distinguish organoid protocols and determine whether a protocol is guided or unguided toward specific neural fate. The 'semi-guided' protocol presented here has shorter induction and differentiation steps with less-specific patterning molecules than most guided protocols but maintains the use of neurotrophic factors such as brain-derived growth factor and neurotrophin-3, unlike unguided approaches. This approach yields the cell type diversity of unguided approaches while maintaining reproducibility for disease modeling. Importantly, we characterized the electrophysiology of these organoids and found that they recapitulate the maturation of neural oscillations observed in the developing human brain, a feature not shown with other approaches. This protocol represents the potential first steps toward bridging molecular and cellular biology to human cognition, and it has already been used to discover underlying features of human brain development, evolution and neurological conditions. Experienced cell culture technicians can expect the protocol to take 1 month, with extended maturation, electrophysiology recording, and adeno-associated virus transduction procedure options.

Cu/Zn bimetallic catalysts prepared by facial potential steps electrodeposition favoring Zn deposition and grain boundary formation for efficient CO2ER to ethylene

Electro-reduction of CO2 (CO2ER) is a promising way to reduce atmospheric CO2 meanwhile gaining high-value-added products (e.g. ethylene). Introducing zinc, a kind of cheap, non-hazardous metal into copper, can perform tandem catalytic functions to overcome the disadvantage of pure Cu. However, due to the quite different theoretical reduction potentials of Cu2+ and Zn2+, Cu/Zn bimetallic catalysts are difficult to be synthesized using the electrochemical method. Here, a facial Potential Steps electrodeposition (PSE) method was proposed to prepare Cu/Zn bimetal catalyst supported on a gas diffusion layer (CuZn/GDE), during which, a lower voltage only suitable for Cu’s deposition was firstly applied, and then a higher voltage was imposed. Worthy mentioned, during the first step, Zn2+ could also transfer to the cathode from the bulk solution and then be embedded by the deposited Cu, forming a capsule-analogous micro-reaction environment composed of highly electron-conductive Cu and enriched Zn2+, thus decreasing the over-potential of Zn’s deposition, further promoting the reduction of Zn & the formation of Cu/Zn grain boundary and the stabilization of Cu(I) in the second step. The optimized CuZn/GDE could achieve a high faradaic efficiency to ethylene (40.2 %) at −1.36 V vs RHE in H-cell. The DFT calculations showed that the *CO formation energy at Cu/Zn and Cu(0)/Cu(I) was lower than at pure Cu and that the formation of *COCOH at Cu(0)/Cu(I) was more thermodynamically favorable than at pure Cu. This work supplies a facial and effective strategy to synthesize copper-based bimetallic catalysts for CO2ER, which could decrease the over-potential of the metal with high deposition potential, and meanwhile form grain boundary, in favor of generation of C2 products.

High-Spatial-Resolution Benchtop X-ray Fluorescence Imaging through Bragg-Diffraction-Based Focusing with Bent Mosaic Graphite Crystals: A Simulation Study.

X-ray fluorescence imaging (XFI) can localize diagnostic or theranostic entities utilizing nanoparticle (NP)-based probes at high resolution in vivo, in vitro, and ex vivo. However, small-animal benchtop XFI systems demonstrating high spatial resolution (variable from sub-millimeter to millimeter range) in vivo are still limited to lighter elements (i.e., atomic number Z≤45). This study investigates the feasibility of focusing hard X-rays from solid-target tubes using ellipsoidal lens systems composed of mosaic graphite crystals with the aim of enabling high-resolution in vivo XFI applications with mid-Z (42≤Z≤64) elements. Monte Carlo simulations are performed to characterize the proposed focusing-optics concept and provide quantitative predictions of the XFI sensitivity, in silico tumor-bearing mice models loaded with palladium (Pd) and barium (Ba) NPs. Based on simulation results, the minimum detectable total mass of PdNPs per scan position is expected to be on the order of a few hundred nanograms under in vivo conform conditions. PdNP masses as low as 150 ng to 50 ng could be detectable with a resolution of 600 μm when imaging abdominal tumor lesions across a range of low-dose (0.8 μGy) to high-dose (8 μGy) exposure scenarios. The proposed focusing-optics concept presents a potential step toward realizing XFI with conventional X-ray tubes for high-resolution applications involving interesting NP formulations.