Diagnostic Algorithm for Intracranial Lesions in the Emergency Department: Effectiveness of the Relative Brain Volume and Hounsfield Unit Value Measured by Perfusion Tomography.

Background Early treatment of intracranial lesions in the emergency department is crucial, but it can be challenging to differentiate between them. This differentiation is essential because the treatment of each type of lesion is different. Cerebral computed tomography perfusion (CTP) imaging can help visualize the vascularity of brain lesions and provide absolute quantification of physiological parameters. Compared to magnetic resonance imaging, CTP has several advantages, such as simplicity, wide availability, and reproducibility. Purpose This study aimed to assess the effectiveness of Hounsfield units (HU) in measuring the density of hypercellular lesions and the ability of CTP to quantify hemodynamics in distinguishing intracranial space-occupying lesions. Methods A retrospective study was conducted from March 2016 to March 2022. All patients underwent CTP and CT scans, and relative cerebral blood volume (rCBV) and HU were obtained for intracranial lesions. Results We included a total of 244 patients in our study. This group consisted of 87 (35.7%) individuals with glioblastomas (GBs), 48 (19.7%) with primary central nervous system lymphoma (PCNSL), 45 (18.4%) with metastases (METs), and 64 (26.2) with abscesses. Our study showed that the HUs for METs were higher than those for GB (S 57.4% and E 88.5%). In addition, rCBV values for PCNSL and abscesses were lower than those for GB and METs. The HU in PCNSL was higher than those in abscesses (S 94.1% and E 96.6%). Conclusion PCT parameters provide valuable information for diagnosing brain lesions. A comprehensive assessment improves accuracy. Combining rCBV and HU enhances diagnostic accuracy, making it a valuable tool for distinguishing between lesions. PCT's widespread availability allows for the use of both anatomical and functional information with high spatial resolution for diagnosing and managing brain tumor patients.

Dissolution Heterogeneity Observed in Anisotropic Ruthenium Dioxide Nanocrystals via Liquid-Phase Transmission Electron Microscopy.

Noble metal oxides such as ruthenium dioxide are highly active electrocatalysts for anodic reactions in acidic electrolytes, but dissolution during electrochemical operation impedes wide-scale applications in renewable energy technologies. Improving the fundamental understanding of the dissolution dynamics of application-relevant morphologies such as nanocrystals is critical for the grid-scale implementation of these materials. Herein, we report the nanoscale heterogeneity observed via liquid-phase transmission electron microscopy during ruthenium dioxide nanocrystal dissolution under oxidizing conditions. Single-crystalline ruthenium dioxide nanocrystals enabled the direct observation of dissolution along different crystallographic facets, allowing an unprecedented direct comparison of crystal facet stability. The nanoscale observations revealed substantial heterogeneity in the relative stability of crystallographic facets across different nanocrystals, attributed to the nanoscale strains present in these crystals. These findings highlight the importance of nanoscale heterogeneity in determining macroscale properties such as electrocatalyst stability and provide a characterization methodology that can be integrated into next-generation electrocatalyst discovery efforts.

Comparison Between Pantoprazole Intermittent Dosing and Continuous Infusion in Suspected Upper Gastrointestinal Bleeding Prior to Endoscopy: Impact of a Pharmacist-Driven Protocol to Reduce Utilization of Pantoprazole Continuous Infusion.

BACKGROUND: Current practice for patients with suspected or confirmed upper gastrointestinal bleeding (GIB) is to utilize a proton pump inhibitor (PPI) bolus followed by a continuous infusion for 72 hours. Literature has shown similar outcomes with intermittent bolus dosing compared to continuous infusion. Substitution would lead to reduced costs and utilization of resources. METHODS: This was a retrospective case-control study conducted via chart review. Utilizing electronic healthcare record reports, patients in the control arm were screened for inclusion if they received a pantoprazole continuous infusion from December 1, 2020, to March 31, 2021. A total of 38 patients were included in the control arm. Patients in the experimental arm were screened for inclusion with pantoprazole intermittent therapy from January 1, 2022, to June 30, 2022. A total of 60 patients were included in the experimental arm. The primary outcome was a 30-day GIB recurrence. Secondary outcomes included 30-day hospital readmission, 30-day Clostridioides difficile (C. difficile), hospital length of stay (LOS), and number of pantoprazole vials utilized. RESULTS: There was a 65% reduction in the 30-day GIB recurrence in the intermittent bolus arm compared to the continuous infusion arm. Thirty-day hospital readmission was 57% lower in the intermittent bolus arm compared to the continuous infusion arm. The LOS between the two arms was almost identical with the median being five days for the intermittent bolus arm and the median being four days for the continuous infusion arm. The 30-day C. difficile infection rate had 5% of patients acquiring C. difficile in the intermittent bolus arm and 2.5% in the continuous infusion arm. The intermittent bolus arm used 55% fewer pantoprazole vials than the continuous infusion arm. CONCLUSION: In hospitalized patients, the utilization of pantoprazole intermittent bolus is not only comparably efficacious but potentially represents a safer and economically advantageous alternative compared to the current guideline recommendation of a 72-hour pantoprazole continuous infusion. Further studies could provide more robust data to support our findings and challenge the current recommendation for patients who meet the indication criteria.

EELS Studies of Cerium Electrolyte Reveal Substantial Solute Concentration Effects in Graphene Liquid Cells.

Graphene liquid cell transmission electron microscopy is a powerful technique to visualize nanoscale dynamics and transformations at atomic resolution. However, the solution in liquid cells is known to be affected by radiolysis, and the stochastic formation of graphene liquid cells raises questions about the solution chemistry in individual pockets. In this study, electron energy loss spectroscopy (EELS) was used to evaluate a model encapsulated solution, aqueous CeCl3. First, the ratio between the O K-edge and Ce M-edge was used to approximate the concentration of cerium salt in the graphene liquid cell. It was determined that the ratio between oxygen and cerium was orders of magnitude lower than what is expected for a dilute solution, indicating that the encapsulated solution is highly concentrated. To probe how this affects the chemistry within graphene liquid cells, the oxidation of Ce3+ was measured using time-resolved parallel EELS. It was determined that Ce3+ oxidizes faster under high electron fluxes, but reaches the same steady-state Ce4+ concentration regardless of flux. The time-resolved concentration profiles enabled direct comparison to radiolysis models, which indicate rate constants and g-values of certain molecular species are substantially different in the highly concentrated environment. Finally, electron flux-dependent gold nanocrystal etching trajectories showed that gold nanocrystals etch faster at higher electron fluxes, correlating well with the Ce3+ oxidation kinetics. Understanding the effects of the highly concentrated solution in graphene liquid cells will provide new insight on previous studies and may open up opportunities to systematically study systems in highly concentrated solutions at high resolution.

Concern about experiencing downward socioeconomic mobility generates precarious types of motivation among students of color.

Students' beliefs about whether they will experience changes in their socioeconomic status influence their academic motivation. We propose that students who are concerned about downward socioeconomic mobility will focus their attention on negative academic outcomes and exhibit motivational goals oriented towards preventing negative possibilities and that this relationship will be particularly pronounced among students of color. Two studies investigated the relationship between college students' concerns about downward socioeconomic mobility and their adoption of academic achievement goals. The more that students of color expressed concerns about experiencing downward socioeconomic mobility, the more they adopted academic mastery-avoidance goals (ß = 0.76), whereas there was no significant relationship between concerns about downward socioeconomic mobility and mastery-avoidance goals among White students (ß = - 0.24; Study 1). Experimentally induced concerns about downward socioeconomic mobility increased academic mastery-avoidance goals among students of color (ß = - 0.58) but decreased mastery-avoidance goals among White students (ß = 0.46; Study 2). Together, results indicate that there is a strong relationship between concerns about downward socioeconomic mobility and mastery-avoidance goals among students of color, highlighting the importance of understating how students of color make sense of their future socioeconomic prospects in order to most effectively support their academic trajectories positively. Supplementary Information: The online version contains supplementary material available at 10.1007/s11218-023-09763-5.

The Ongoing Development of Strength-Based Approaches to People Who Hold Systemically Marginalized Identities.

ACADEMIC ABSTRACT: Personality and social psychology have historically viewed individuals' systemically marginalized identities (e.g., as people of color, as coming from a lower-income background) as barriers to their success. Such a deficit-based perspective limits psychological science by overlooking the broader experiences, value, perspectives, and strengths that individuals who face systemic marginalization often bring to their societies. The current article aims to support future research in incorporating a strength-based lens through tracing psychology's journey away from an emphasis on deficits among people who contend with systemic marginalization and toward three distinct strength-based approaches: the universal strengths, difference-as-strength, and identity-specific strengths approaches. Through distinguishing between each approach, we advance scholarship that aims to understand systemically marginalized identities with corresponding implications for addressing inequality. Strength-based approaches guide the field to recognize the imposed limitations of deficit-based ideologies and advance opportunities to engage in research that effectively understands and values systemically marginalized people. PUBLIC ABSTRACT: Inequalities, including those between people from higher- and lower-income backgrounds, are present across society. From schools to workplaces, hospitals to courtrooms, people who come from backgrounds that are marginalized by society often face more negative outcomes than people from more privileged backgrounds. While such inequalities are often blamed on a lack of hard work or other issues within marginalized people themselves, scientific research increasingly demonstrates that this is not the case. Rather, studies consistently find that people's identities as coming from groups that face marginalization in society often serve as a valuable source of unique strengths, not deficiencies, that can help them succeed. Our article reviews these studies to examine how future research in psychology may gain a broader understanding of people who contend with marginalization. In doing so, we outline opportunities for psychological research to effectively support efforts to address persistent inequalities.

Educators' Beliefs About Students' Socioeconomic Backgrounds as a Pathway for Supporting Motivation.

Students' understandings of their socioeconomic status (SES) backgrounds have important implications for their motivation, achievement, and the emergence of SES-based educational disparities. Educators' beliefs about students' backgrounds likely play a meaningful role in shaping these understandings and, thus, may represent an important opportunity to support students from lower-SES backgrounds. We first experimentally demonstrate that educators can be encouraged to adopt background-specific strengths beliefs-which view students' lower-SES backgrounds as potential sources of unique and beneficial strengths (NStudy 1 = 125). Subsequently, we find that exposure to educators who communicate background-specific strengths beliefs positively influences the motivation and academic persistence of students, particularly those from lower-SES backgrounds (NStudy 2 = 256; NStudy 3 = 276). Furthermore, lower-SES students' own beliefs about their backgrounds mediated these effects. Altogether, our work contributes to social-psychological theory and practice regarding how key societal contexts can promote equity through identity-based processes.

Facet-selective etching trajectories of individual semiconductor nanocrystals.

The size and shape of semiconductor nanocrystals govern their optical and electronic properties. Liquid cell transmission electron microscopy (LCTEM) is an emerging tool that can directly visualize nanoscale chemical transformations and therefore inform the precise synthesis of nanostructures with desired functions. However, it remains difficult to controllably investigate the reactions of semiconductor nanocrystals with LCTEM, because of the highly reactive environment formed by radiolysis of liquid. Here, we harness the radiolysis processes and report the single-particle etching trajectories of prototypical semiconductor nanomaterials with well-defined crystalline facets. Lead selenide nanocubes represent an isotropic structure that retains the cubic shape during etching via a layer-by-layer mechanism. The anisotropic arrow-shaped cadmium selenide nanorods have polar facets terminated by either cadmium or selenium atoms, and the transformation trajectory is driven by etching the selenium-terminated facets. LCTEM trajectories reveal how nanoscale shape transformations of semiconductors are governed by the reactivity of specific facets in liquid environments.

Elucidating the Role of Halides and Iron during Radiolysis-Driven Oxidative Etching of Gold Nanocrystals Using Liquid Cell Transmission Electron Microscopy and Pulse Radiolysis.

Graphene liquid cell transmission electron microscopy (TEM) has enabled the observation of a variety of nanoscale transformations. Yet understanding the chemistry of the liquid cell solution and its impact on the observed transformations remains an important step toward translating insights from liquid cell TEM to benchtop chemistry. Gold nanocrystal etching can be used as a model system to probe the reactivity of the solution. FeCl3 has been widely used to promote gold oxidation in bulk and liquid cell TEM studies, but the roles of the halide and iron species have not been fully elucidated. In this work, we observed the etching trajectories of gold nanocrystals in different iron halide solutions. We observed an increase in gold nanocrystal etch rate going from Cl-- to Br-- to I--containing solutions. This is consistent with a mechanism in which the dominant role of halides is as complexation agents for oxidized gold species. Additionally, the mechanism through which FeCl3 induces etching in liquid cell TEM remains unclear. Ground-state bleaching of the Fe(III) absorption band observed through pulse radiolysis indicates that iron may react with Cl2·- radicals to form an oxidized transient species under irradiation. Complete active space self-consistent field (CASSCF) calculations indicate that the FeCl3 complex is oxidized to an Fe species with an OH radical ligand. Together our data indicate that an oxidized Fe species may be the active oxidant, while halides modulate the etch rate by tuning the reduction potential of gold nanocrystals.

Redox Mediated Control of Electrochemical Potential in Liquid Cell Electron Microscopy.

Liquid cell electron microscopy enables the study of nanoscale transformations in solvents with high spatial and temporal resolution, but for the technique to achieve its potential requires a new level of control over the reactivity caused by radical generation under electron beam irradiation. An understanding of how to control electron-solvent interactions is needed to further advance the study of structural dynamics for complex materials at the nanoscale. We developed an approach that scavenges radicals with redox species that form well-defined redox couples and control the electrochemical potential in situ. This approach enables the observation of electrochemical structural dynamics at near-atomic resolution with precise control of the liquid environment. Analysis of nanocrystal etching trajectories indicates that this approach can be generalized to several chemical systems. The ability to simultaneously observe heterogeneous reactions at near-atomic resolution and precisely control the electrochemical potential enables the fundamental study of complex nanoscale dynamics with unprecedented detail.

In Situ Quantification of Interactions between Charged Nanorods in a Predefined Potential Energy Landscape.

Quantitative understanding of nanoscale interactions is a prerequisite for harnessing the remarkable collective properties of nanoparticle systems. Here, we report the combined use of liquid-phase transmission electron microscopy and electron beam lithography to elucidate the interactions between charged nanorods in a predefined potential energy landscape. In situ site-selective lift-off of surface-functionalized lithographed gold nanorods is achieved by patterning them with adhesion layer materials that undergo etching at different rates. Analysis of the subsequent nanorod motion, which is two-dimensionally confined as a result of the particle-substrate attraction, allows quantification of interparticle interactions in a lithographically engineered environment. For lithographed nanorods patterned with the same adhesion layer material, their self-assembly behavior following lift-off is tuned by changing their starting spatial arrangement. Our approach facilitates investigation of interparticle interactions in designed nanoparticle systems and affords fundamental insights into the role of the potential energy landscape in determining the kinetic pathway for nanoparticle self-assembly.

Precise Colloidal Plasmonic Photocatalysts Constructed by Multistep Photodepositions.

Natural photosynthesis relies on a sophisticated charge transfer pathway among multiple components with precise spatial, energetic, and temporal organizations in the aqueous environment. It continues to inspire and challenge the design and fabrication of artificial multicomponent colloidal nanostructures for solar-to-fuel conversion. Herein, we introduce a plasmonic photocatalyst synthesized with colloidal methods with five integrated components including cocatalysts installed in orthogonal locations. The precise deposition of individual inorganic components on an Au/TiO2 nanodumbell nanostructure is enabled by photoreduction and photo-oxidation, which selectively occurs at the TiO2 tip sites and Au lateral sites, respectively. Under visible-light irradiation, the photocatalyst exhibited activity of oxygen evolution from water without scavengers. We demonstrate that each component is essential for improving the photocatalytic performance. In addition, mechanistic studies suggest that the photocatalytic reaction requires combining the hot charge carriers derived from exciting both the d-sp interband transition and the localized surface plasmon resonance of Au.

Self-Limiting Shell Formation in Cu@Ag Core-Shell Nanocrystals during Galvanic Replacement.

The understanding of synthetic pathways of bimetallic nanocrystals remains limited due to the complex energy landscapes and dynamics involved. In this work, we investigate the formation of self-limiting Cu@Ag core-shell nanoparticles starting from Cu nanocrystals followed by galvanic replacement with Ag ions. Bulk quantification with atomic emission spectroscopy and spatially resolved elemental mapping with electron microscopy reveal distinct nucleation regimes that produce nanoparticles with a tunable Ag shell thickness, but only up to a certain limiting thickness. We develop a quantitative transport model that explains this observed self-limiting structure as arising from the balance between entropy-driven interdiffusion and a positive mixing enthalpy. The proposed model depends only on the intrinsic physical properties of the system such as diffusivity and mixing energy and directly yields a high level of agreement with the elemental mapping profiles without requiring additional fit parameters.

Maternal Flavonoids Intake Reverts Depression-Like Behaviour in Rat Female Offspring.

Maternal hypercaloric exposure during pregnancy and lactation is a risk factor for developing diseases associated with inflammation such as obesity, diabetes and, neurological diseases in the offspring. Neuroinflammation might modulate neuronal activation and flavonoids are dietary compounds that have been proven to exert anti-inflammatory properties. Thus, the aim of the present study is to evaluate the effect of maternal supplementation with flavonoids (kaempferol-3-O-glucoside and narirutin) on the prevention of depression-like behaviour in the female offspring of dams fed with an obesogenic diet during the perinatal period. Maternal programming was induced by high fat (HFD), high sugar (HSD), or cafeteria diets exposure and depressive like-behaviour, referred to as swimming, climbing, and immobility events, was evaluated around postnatal day 56⁻60 before and after 30 mg/kg i.p. imipramine administration in the female offspring groups. Central inflammation was analyzed by measuring the TANK binding kinase 1 (TBK1) expression. We found that the offspring of mothers exposed to HSD programming failed to show the expected antidepressant effect of imipramine. Also, imipramine injection, to the offspring of mothers exposed to cafeteria diet, displayed a pro-depressive like-behaviour phenotype. However, dietary supplementation with flavonoids reverted the depression-like behaviour in the female offspring. Finally, we found that HSD programming increases the TBK1 inflammatory protein marker in the hippocampus. Our data suggest that maternal HSD programming disrupts the antidepressant effect of imipramine whereas cafeteria diet exposure leads to depressive-like behaviour in female offspring, which is reverted by maternal flavonoid supplementation.

Photoelectrochemical Behavior of a Molecular Ru-Based Water-Oxidation Catalyst Bound to TiO2-Protected Si Photoanodes.

A hybrid photoanode based on a molecular water oxidation precatalyst was prepared from TiO2-protected n- or p+-Si coated with multiwalled carbon nanotubes (CNT) and the ruthenium-based water oxidation precatalyst [RuIV(tda)(py-pyr)2(O)], 1(O) (tda2- is [2,2':6',2″-terpyridine]-6,6″-dicarboxylato and py-pir is 4-(pyren-1-yl)-N-(pyridin-4-ylmethyl)butanamide). The Ru complex was immobilized by π-π stacking onto CNTs that had been deposited by drop casting onto Si electrodes coated with 60 nm of amorphous TiO2 and 20 nm of a layer of sputtered C. At pH = 7 with 3 Sun illumination, the n-Si/TiO2/C/CNT/[1+1(O)] electrodes exhibited current densities of 1 mA cm-2 at 1.07 V vs NHE. The current density was maintained for >200 min at a constant potential while intermittently collecting voltammograms that indicated that over half of the Ru was still in molecular form after O2 evolution.