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The ability to freeze and stabilize reaction intermediates in their metastable states and obtain their structural and chemical information with high spatial resolution is critical to advance materials technologies such as catalysis and batteries. Here, we develop an electrified operando-freezing methodology to preserve these metastable states under electrochemical reaction conditions for cryogenic electron microscopy (cryo-EM) imaging and spectroscopy. Using Cu catalysts for CO2 reduction as a model system, we observe restructuring of the Cu catalyst in a CO2 atmosphere while the same catalyst remains intact in air at the nanometer scale. Furthermore, we discover the existence of a single valence Cu (1+) state and C-O bonding at the electrified liquid-solid interface of the operando-frozen samples, which are key reaction intermediates that traditional ex situ measurements fail to detect. This work highlights our novel technique to study the local structure and chemistry of electrified liquid-solid interfaces, with broad impact beyond catalysis.
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Childhood adversity stains the past of millions of working adults worldwide. The impact on health and well-being is substantial-a now-acknowledged public health crisis. Yet, research in the organizational sciences has failed to recognize the burden that individuals with this difficult history carry with them into the workforce. By synthesizing an interdisciplinary body of scholarship into a cohesive theoretical framework, we provide a foundation for emerging work in occupational health psychology. Empirically, across two single-level multiwave studies, we demonstrate the importance of adversity in one's childhood and its impact on the workplace specifically showing that child adversity, directly and indirectly, impacts worker attitudes and discretionary behaviors. Further, providing one of the few examinations of stress proliferation theory in the workplace, we demonstrate adulthood adversity as an essential mediating mechanism that leads to these work outcomes. From an applied perspective, our results highlight a need to focus on the healing and recovery of adult survivors as they work toward breaking the chains of the past in their lives and at work. In presenting this life course perspective on organizational attitudes and behaviors, our work offers a unique and vital contribution to occupational health theory, practice, and research. (PsycInfo Database Record (c) 2024 APA, all rights reserved).
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Actitud , Humanos , Adulto , Femenino , Masculino , Lugar de Trabajo/psicología , Persona de Mediana Edad , Cultura Organizacional , Niño , Experiencias Adversas de la Infancia , Estrés Psicológico/psicología , Estrés Laboral/psicologíaRESUMEN
Despite financial concerns representing of the most substantial sources of stress, the intersection between individual differences and financial stress has received sparce attention. Emphasizing the cognitive-appraisal process, our study reveals financial stress perceptions partly reflect a dispositional tendency to interpret financial information either more positively or negatively. Across two studies (N = 441; N = 348), we found that positive and negative affect predict subjective financial perceptions of income adequacy. Further, using Relative Weights Analysis, we demonstrate that in predicting financial stress perceptions, dispositional affect is as important as, or more important than, objective measures of financial stress (i.e., household income and debt). Lastly, using moderated mediation, we found that both current and future perceived income adequacy mediate the relationship between one's income and their experience of affective financial strain, and dispositional affect moderates this relationship. Our work informs current research and interventions seeking to understand individual differences in financial stress perceptions.
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Diamond color centers have proven to be versatile quantum emitters and exquisite sensors of stress, temperature, electric and magnetic fields, and biochemical processes. Among color centers, the silicon-vacancy (SiV[Formula: see text]) defect exhibits high brightness, minimal phonon coupling, narrow optical linewidths, and high degrees of photon indistinguishability. Yet the creation of reliable and scalable SiV[Formula: see text]-based color centers has been hampered by heterogeneous emission, theorized to originate from surface imperfections, crystal lattice strain, defect symmetry, or other lattice impurities. Here, we advance high-resolution cryo-electron microscopy combined with cathodoluminescence spectroscopy and 4D scanning transmission electron microscopy (STEM) to elucidate the structural sources of heterogeneity in SiV[Formula: see text] emission from nanodiamond with sub-nanometer-scale resolution. Our diamond nanoparticles are grown directly on TEM membranes from molecular-level seedings, representing the natural formation conditions of color centers in diamond. We show that individual subcrystallites within a single nanodiamond exhibit distinct zero-phonon line (ZPL) energies and differences in brightness that can vary by 0.1 meV in energy and over 70% in brightness. These changes are correlated with the atomic-scale lattice structure. We find that ZPL blue-shifts result from tensile strain, while ZPL red shifts are due to compressive strain. We also find that distinct crystallites host distinct densities of SiV[Formula: see text] emitters and that grain boundaries impact SiV[Formula: see text] emission significantly. Finally, we interrogate nanodiamonds as small as 40 nm in diameter and show that these diamonds exhibit no spatial change to their ZPL energy. Our work provides a foundation for atomic-scale structure-emission correlation, e.g., of single atomic defects in a range of quantum and two-dimensional materials.
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We expand the concept of epitaxy to a regime of "twisted epitaxy" with the epilayer crystal orientation between two substrates influenced by their relative orientation. We annealed nanometer-thick gold (Au) nanoparticles between two substrates of exfoliated hexagonal molybdenum disulfide (MoS2) with varying orientation of their basal planes with a mutual twist angle ranging from 0° to 60°. Transmission electron microscopy studies show that Au aligns midway between the top and bottom MoS2 when the twist angle of the bilayer is small (<~7°). For larger twist angles, Au has only a small misorientation with the bottom MoS2 that varies approximately sinusoidally with twist angle of the bilayer MoS2. Four-dimensional scanning transmission electron microscopy analysis further reveals a periodic strain variation (<|±0.5%|) in the Au nanodisks associated with the twisted epitaxy, consistent with the Moiré registry of the two MoS2 twisted layers.
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The propensity to metastasize is the most important prognostic indicator for solid cancers. New insights into the mechanisms of early carcinogenesis have revealed micrometastases are generated far earlier than previously thought. Evidence supports a synergistic relationship between vascular and lymphatic seeding which can occur before there is clinical evidence of a primary tumour. Early vascular seeding prepares distal sites for colonisation while regional lymphatics are co-opted to promote facilitative cancer cell mutations. In response, the host mounts a global inflammatory and immunomodulatory response towards these cells supporting the concept that cancer is a systemic disease. Cancer staging systems should be refined to better reflect cancer cell loads in various tissue compartments while clinical perspectives should be broadened to encompass this view when approaching high-risk cancers. Measured adjunctive therapies implemented earlier for low-volume, in-transit cancer offers the prospect of preventing advanced disease and the need for heroic therapeutic interventions. This review seeks to re-appraise how we view the metastatic process for solid cancers. It will explore in-transit metastasis in the context of high-risk skin cancer and how it dictates disease progression. It will also discuss how these implications will influence our current staging systems and its consequences on management.
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Micrometástasis de Neoplasia , Neoplasias Cutáneas , Humanos , Metástasis Linfática , Micrometástasis de Neoplasia/patología , Neoplasias Cutáneas/patología , Pronóstico , Piel/patología , Biopsia del Ganglio Linfático Centinela , Estadificación de NeoplasiasRESUMEN
OBJECTIVE: The objective of this research was to assess the relative contribution of three resilience-related dispositional resources (trait mindfulness, core self-evaluations, and optimism) to emergency medicine physicians' fatigue, retention, and productivity. METHODS: We surveyed emergency physicians employed by a national (US) medical staffing organization. The survey included measures of work stressors, resilience resources, job search behavior, and fatigue. We linked the survey responses to objective demographic and productivity measures from the organization's records. RESULTS: A total of 371 respondents completed the survey. Multiple regression analyses demonstrated support for each of the three resilience-related resources as predictors. Relative weights analyses showed that resilience accounted for 14% and 62% of the outcome variance, whereas work demands accounted for between 32% and 56%. CONCLUSIONS: Multiple facets of dispositional resilience are important predictors of emergency medicine physicians' occupational health, retention, and productivity.
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Agotamiento Profesional , Médicos , Humanos , Encuestas y Cuestionarios , Análisis de Regresión , Fatiga , Satisfacción en el TrabajoRESUMEN
Access to abortion care has a profound impact on women's ability to participate in the workforce. In the US, restrictions on abortion care have waxed and waned over the years, including periods when abortion was broadly permitted across the nation for most pregnant people for a substantial proportion of pregnancy and times when restrictions varied across states, including states where abortion is banned for nearly all reasons. Additionally, access to abortion care has always been a reproductive justice issue, with some people more able to access this care than others even when it is structurally available. In June 2022, the US Supreme Court handed down the Dobbs v. Jackson Women's Health Organization, returning to states the ability to determine restrictions on abortion, including near-total bans on abortion. In this anthology, ten experts share their perspectives on what the Dobbs decision means for the future, how it will exacerbate existing, well-researched issues, and likely also create new challenges needing investigation. Some contributions are focused on research directions, some focus on implications for organizations, and most include both. All contributions share relevant occupational health literature and describe the effects of the Dobbs decision in context.
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Workaholism is increasingly recognized as a potential threat to occupational health. Although most research has conceptualized workaholism as a trait, some research suggests that it may also fluctuate from day to day. Moreover, the effects of the dynamic properties of workaholism on work and family outcomes may be contingent on one's economic situation. Therefore, the aim of the present study was to test the interactive effect of workday workaholism and economic resources on nightly work-family conflict and family engagement. Using experience sampling methodology, we demonstrated that workaholism fluctuates from one day to the next and has detrimental short-term effects on work-family conflict. Additionally, our findings indicated that the interaction between workday workaholism and perceived income adequacy predicted both nighty work-family conflict and family engagement. While the association between workday workaholism and work-family conflict was stronger for those who experienced low income adequacy, the relationship between workaholism and family engagement was stronger for those who exhibited high income adequacy. Similarly, job security buffered the effect of workaholism on work-family conflict. We discuss the theoretical and practice implications of this study as well as recommend future research directions.
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Conducta Adictiva , Salud Laboral , Humanos , Conflicto Familiar , Evaluación Ecológica MomentáneaRESUMEN
Social resource crafting is a job crafting strategy in which employees proactively increase their social resources (e.g., feedback from coworkers, coaching from supervisor). We examined social resource crafting's relationships with work-related social support (perceived supervisor and coworker support) and work engagement. Specifically, as there has been growing interest in understanding resource crafting and work engagement, we investigated the directionality of this relationship. Using a two-wave study and structural equation modelling, we tested the dual pathways between resource crafting and work engagement as well as resource crafting's relationship with each type of support. The results suggested social resource crafting was associated with higher levels of coworker support-but not supervisor support - over time and supported a unidirectional path from social resource crafting to work engagement. Our findings provide valuable insight into the power employees have to craft their own positive experiences at work.
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Relaciones Interpersonales , Compromiso Laboral , Humanos , Apoyo Social , Satisfacción en el TrabajoRESUMEN
Poor fast-charge capabilities limit the usage of rechargeable Li metal anodes. Understanding the connection between charging rate, electroplating mechanism, and Li morphology could enable fast-charging solutions. Here, we develop a combined electroanalytical and nanoscale characterization approach to resolve the current-dependent regimes of Li plating mechanisms and morphology. Measurement of Li+ transport through the solid electrolyte interphase (SEI) shows that low currents induce plating at buried Li||SEI interfaces, but high currents initiate SEI-breakdown and plating at fresh Li||electrolyte interfaces. The latter pathway can induce uniform growth of {110}-faceted Li at extremely high currents, suggesting ion-transport limitations alone are insufficient to predict Li morphology. At battery relevant fast-charging rates, SEI-breakdown above a critical current density produces detrimental morphology and poor cyclability. Thus, prevention of both SEI-breakdown and slow ion-transport in the electrolyte is essential. This mechanistic insight can inform further electrolyte engineering and customization of fast-charging protocols for Li metal batteries.
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Current clinical brain tumour therapy practices are based on tumour resection and post-operative chemotherapy or X-ray radiation. Resection requires technically challenging open-skull surgeries that can lead to major neurological deficits and, in some cases, death. Treatments with X-ray and chemotherapy, on the other hand, cause major side-effects such as damage to surrounding normal brain tissues and other organs. Here we report the development of an integrated nanomedicine-bioelectronics brain-machine interface that enables continuous and on-demand treatment of brain tumours, without open-skull surgery and toxicological side-effects on other organs. Near-infrared surface plasmon characteristics of our gold nanostars enabled the precise treatment of deep brain tumours in freely behaving mice. Moreover, the nanostars' surface coating enabled their selective diffusion in tumour tissues after intratumoral administration, leading to the exclusive heating of tumours for treatment. This versatile remotely controlled and wireless method allows the adjustment of nanoparticles' photothermal strength, as well as power and wavelength of the therapeutic light, to target tumours in different anatomical locations within the brain.
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Neoplasias Encefálicas , Nanopartículas , Fotoquimioterapia , Animales , Neoplasias Encefálicas/tratamiento farmacológico , Línea Celular Tumoral , Oro/uso terapéutico , Ratones , Nanomedicina TeranósticaRESUMEN
PURPOSE: Evaluate the use of widefield radiation therapy (RT) in the management of extensive skin field cancerization (ESFC) with/without keratinocyte cancer (KC). METHODS: The National Dermatology Radiation Oncology Registry is a multidisciplinary collaboration (dermatologists and radiation oncologists). It captures disease description, prior therapies, radiation prescription, clinical effect, skin cosmesis scores, and toxicity data. This analysis included 12-month follow-up data on 89 treated fields from a subset of 83 patients. RESULTS: Clinical success (>90% field clearance) was 96% (ESFC, n = 63) and 88% (ESFC with KC, n = 26). Complete lesion response was seen in 96% of evaluable (n = 25) ESFC with KC. Recurrence (4/89 [5%]) and appearance of new lesions (10/89 [11%]) were minimal. Cosmetic outcome was excellent/good in 98% ESFC and 96% ESFC with KC. Grade 1-2 acute radiation dermatitis occurred in up to 80% of treated fields. The frequency of Grade 3 acute skin toxicities was low. CONCLUSIONS: Registry data demonstrate the potential for widefield RT to treat patients with significant skin pathology who have exhausted other therapies and require durable, minimally invasive treatment options. At 12 months, observed clinical success rates were higher than those reported for topical interventions for ESFC. Ongoing follow-up is required to determine longer term outcomes.
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Neoplasias , Piel , Humanos , Queratinocitos , Piel/efectos de la radiaciónRESUMEN
Extensive Skin Field Cancerization (ESFC) describes multiple actinic keratoses, with and without keratinocyte skin cancers. These areas are characterised by dysplastic keratoses, are prone to new malignancies, involve significant morbidity, have a poor cosmetic appearance, and impact negatively on quality of life. Available topical field therapies have limited durability of efficacy. Volumetric modulated arc therapy (VMAT) is an advanced form of intensity-modulated radiotherapy which achieves highly modulated and conformal dosimetry, delivering a homogeneous dose, particularly over curved surfaces, for example, scalps and limbs. This series describes the 12-month follow-up analysis of 41 VMAT treated fields from 32 (21 M, 11 F) patients. Consent was obtained after VMAT treatment to allow access to outcomes data. Conditions treated include ESFC, Bowen's disease/SCC in situ, cutaneous squamous cell carcinoma, and basal cell carcinoma (BCC). Efficacy was measured by the percentage reduction of visible pathology within the treatment field. The primary endpoint for this review was the assessment of treatment success, defined as >90% clearance of the treatment field. As part of this definition, the appearance of isolated keratoses at 12 months was considered not significant if the field overall was clear. The development of new or recurrent cancers within the 12-month follow-up period was recorded. Thirty-six fields (87%) achieved a clinical clearance >90%. Of those, 33 (80%) fields achieved complete clearance >99% of visible actinic keratosis or keratinocyte cancers. Three fields (7%) demonstrated 91-99% clinical clearance, and no treatment failures were recorded. Two newly occurring lesions (1 BCC and 1 SCC in situ) were identified within a treated field at 12 months. The reported toxicities at 12-month post-treatment were grade 1 or 2 only, with no cases of persistent radiation dermatitis. Toxicities reported in more than 5% of cases included: alopecia (n = 4); dryness (n= 3); erythema (n = 2); and telangiectasia ulceration (n = 4). The high rate of complete clearance at 12 months seen in this case series compares very favourably with other treatments, including topical 5-fluorouracil, imiquimod, and photodynamic therapy. Toxicities reported in our patient population demonstrated that VMAT was well tolerated at 12-month post-treatment. VMAT treatment may play a growing role in future therapy for ESFC with and without keratinocyte cancers.
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The development of inexpensive and abundant catalysts with high activity, selectivity, and stability for the oxygen reduction reaction (ORR) is imperative for the widespread implementation of fuel cell devices. Herein, we present a combined theoretical-experimental approach to discover and design first-row transition metal antimonates as excellent electrocatalytic materials for the ORR. Theoretically, we identify first-row transition metal antimonatesâMSb2O6, where M = Mn, Fe, Co, and Niâas nonprecious metal catalysts with good oxygen binding energetics, conductivity, thermodynamic phase stability, and aqueous stability. Among the considered antimonates, MnSb2O6 shows the highest theoretical ORR activity based on the 4e- ORR kinetic volcano. Experimentally, nanoparticulate transition metal antimonate catalysts are found to have a minimum of a 2.5-fold enhancement in intrinsic mass activity (on transition metal mass basis) relative to the corresponding transition metal oxide at 0.7 V vs RHE in 0.1 M KOH. MnSb2O6 is the most active catalyst under these conditions, with a 3.5-fold enhancement on a per Mn mass activity basis and 25-fold enhancement on a surface area basis over its antimony-free counterpart. Electrocatalytic and material stability are demonstrated over a 5 h chronopotentiometry experiment in the stability window identified by theoretical Pourbaix analysis. This study further highlights the stable and electrically conductive antimonate structure as a framework to tune the activity and selectivity of nonprecious metal oxide active sites for ORR catalysis.
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BACKGROUND: A range of 'field-directed' treatments is available for the management of extensive skin field cancerization (ESFC), but to date, the only validated objective quantitative tools are limited to assessment of actinic keratoses (AKs) affecting the head. AIMS: To develop a versatile quantitative instrument for objective clinical assessment of ESFC and perform initial internal validation across multiple anatomical zones. METHODS: The study comprised instrument development, pilot testing and instrument refinement and two rounds of reliability and inter-rater validation testing. The study was noninterventional and used a convenience sample of de-identified patient photographs selected based on preset criteria. An expert panel developed the instrument and scoring system via a modified Delphi voting process. A sample of 16 healthcare professionals from multiple specialties undertook the pilot testing, and a panel of seven dermatologists were involved in validation testing. Validation was determined by assessment of overall inter-rater agreement using Gwet chance-corrected agreement coefficients (ACs). RESULTS: The instrument produced, called the Method for Assessing Skin Cancer and Keratoses™ (MASCK™), comprises the Skin Field Cancerization Index (SFCIndex), derived from area of skin involvement and AKs (number and thickness), a global assessment score and a cancer-in-zone score, and uses Likert scales for quantitative scoring. The SFCIndex is a composite score comprising the number and thickness of AKs multiplied by area of skin involvement. ACs for the SFCIndex components, the overall SFCIndex score and the global assessment score were > 0.80 (rated 'almost perfect') while the AC for the cancer-in-zone metric was lower (0.33, rated 'fair'). Internal consistency was demonstrated via positive correlation between the overall SFCIndex score and the global assessment score. CONCLUSIONS: Our study found near-perfect agreement in inter-rater reliability when using MASCK to assess the severity of ESFC in multiple anatomical sites. Further validation of this novel instrument is planned to specifically assess its reliability, utility and feasibility in clinical practice.
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Queratosis Actínica , Neoplasias Cutáneas , Humanos , Queratosis Actínica/diagnóstico , Fotograbar , Reproducibilidad de los Resultados , Proyectos de Investigación , Neoplasias Cutáneas/diagnósticoRESUMEN
BACKGROUND: Anthracycline-induced cardiomyopathy (AIC) is a significant source of morbidity and mortality in cancer survivors. The role of mesenchymal stem cells (MSCs) in treating AIC was evaluated in the SENECA trial, a Phase 1 National Heart, Lung, and Blood Institute-sponsored study, but the mechanisms underpinning efficacy in human tissue need clarification. OBJECTIVES: The purpose of this study was to perform an in vitro clinical trial evaluating the efficacy and putative mechanisms of SENECA trial-specific MSCs in treating doxorubicin (DOX) injury, using patient-specific induced pluripotent stem cell-derived cardiomyocytes (iCMs) generated from SENECA patients. METHODS: Patient-specific iCMs were injured with 1 µmol/L DOX for 24 hours, treated with extracellular vesicles (EVs) from MSCs by either coculture or direct incubation and then assessed for viability and markers of improved cellular physiology. MSC-derived EVs were separated into large extracellular vesicles (L-EVs) (>200 nm) and small EVs (<220nm) using a novel filtration system. RESULTS: iCMs cocultured with MSCs in a transwell system demonstrated improved iCM viability and attenuated apoptosis. L-EVs but not small EVs recapitulated this therapeutic effect. L-EVs were found to be enriched in mitochondria, which were shown to be taken up by iCMs. iCMs treated with L-EVs demonstrated improved contractility, reactive oxygen species production, ATP production, and mitochondrial biogenesis. Inhibiting L-EV mitochondrial function with 1-methyl-4-phenylpyridinium attenuated efficacy. CONCLUSIONS: L-EV-mediated mitochondrial transfer mitigates DOX injury in patient-specific iCMs. Although SENECA was not designed to test MSC efficacy, consistent tendencies toward a positive effect were observed across endpoints. Our results suggest a mechanism by which MSCs may improve cardiovascular performance in AIC independent of regeneration, which could inform future trial design evaluating the therapeutic potential of MSCs.
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Molecular dynamics simulation is now a widespread approach for understanding complex systems on the atomistic scale. It finds applications from physics and chemistry to engineering, life and medical science. In the last decade, the approach has begun to advance from being a computer-based means of rationalizing experimental observations to producing apparently credible predictions for a number of real-world applications within industrial sectors such as advanced materials and drug discovery. However, key aspects concerning the reproducibility of the method have not kept pace with the speed of its uptake in the scientific community. Here, we present a discussion of uncertainty quantification for molecular dynamics simulation designed to endow the method with better error estimates that will enable it to be used to report actionable results. The approach adopted is a standard one in the field of uncertainty quantification, namely using ensemble methods, in which a sufficiently large number of replicas are run concurrently, from which reliable statistics can be extracted. Indeed, because molecular dynamics is intrinsically chaotic, the need to use ensemble methods is fundamental and holds regardless of the duration of the simulations performed. We discuss the approach and illustrate it in a range of applications from materials science to ligand-protein binding free energy estimation. This article is part of the theme issue 'Reliability and reproducibility in computational science: implementing verification, validation and uncertainty quantification in silico'.