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To fuel accelerated proliferation, leukaemic cells undergo metabolic deregulation, which can result in specific nutrient dependencies. Here, we perform an amino acid drop-out screen and apply pre-clinical models of chronic phase chronic myeloid leukaemia (CML) to identify arginine as a nutrient essential for primary human CML cells. Analysis of the Microarray Innovations in Leukaemia (MILE) dataset uncovers reduced ASS1 levels in CML compared to most other leukaemia types. Stable isotope tracing reveals repressed activity of all urea cycle enzymes in patient-derived CML CD34+ cells, rendering them arginine auxotrophic. Thus, arginine deprivation completely blocks proliferation of CML CD34+ cells and induces significantly higher levels of apoptosis when compared to arginine-deprived cell lines. Similarly, primary CML cells, but not normal CD34+ samples, are particularly sensitive to treatment with the arginine-depleting enzyme, BCT-100, which induces apoptosis and reduces clonogenicity. Moreover, BCT-100 is highly efficacious in a patient-derived xenograft model, causing > 90% reduction in the number of human leukaemic stem cells (LSCs). These findings indicate arginine depletion to be a promising and novel strategy to eradicate therapy resistant LSCs.
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Arginina , Leucemia Mielógena Crónica BCR-ABL Positiva , Humanos , Arginina/metabolismo , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Leucemia Mielógena Crónica BCR-ABL Positiva/metabolismo , Apoptosis , Células Madre/metabolismo , Células Madre Neoplásicas/metabolismoRESUMEN
The ability to manipulate the twisting topology of van der Waals structures offers a new degree of freedom through which to tailor their electrical and optical properties. The twist angle strongly affects the electronic states, excitons and phonons of the twisted structures through interlayer coupling, giving rise to exotic optical, electric and spintronic behaviours1-5. In twisted bilayer graphene, at certain twist angles, long-range periodicity associated with moiré patterns introduces flat electronic bands and highly localized electronic states, resulting in Mott insulating behaviour and superconductivity3,4. Theoretical studies suggest that these twist-induced phenomena are common to layered materials such as transition-metal dichalcogenides and black phosphorus6,7. Twisted van der Waals structures are usually created using a transfer-stacking method, but this method cannot be used for materials with relatively strong interlayer binding. Facile bottom-up growth methods could provide an alternative means to create twisted van der Waals structures. Here we demonstrate that the Eshelby twist, which is associated with a screw dislocation (a chiral topological defect), can drive the formation of such structures on scales ranging from the nanoscale to the mesoscale. In the synthesis, axial screw dislocations are first introduced into nanowires growing along the stacking direction, yielding van der Waals nanostructures with continuous twisting in which the total twist rates are defined by the radii of the nanowires. Further radial growth of those twisted nanowires that are attached to the substrate leads to an increase in elastic energy, as the total twist rate is fixed by the substrate. The stored elastic energy can be reduced by accommodating the fixed twist rate in a series of discrete jumps. This yields mesoscale twisting structures consisting of a helical assembly of nanoplates demarcated by atomically sharp interfaces with a range of twist angles. We further show that the twisting topology can be tailored by controlling the radial size of the structure.
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Black phosphorus (BP) is a narrow bandgap (â¼0.3 eV) semiconductor with a great potential for optoelectronic devices in the mid-infrared wavelength. However, it has been challenging to achieve a high-quality scalable BP thin film. Here we present the successful synthesis of optically active BP films on a centimeter scale. We utilize the pulsed laser deposition of amorphous red phosphorus, another allotrope of phosphorus, followed by a high-pressure treatment at â¼8 GPa to induce a phase conversion into BP crystals. The crystalline quality was improved through thermal annealing, resulting in the observation of photoluminescence emission at mid-infrared wavelengths. We demonstrate high-pressure conversion on a centimeter scale with a continuous film with a thickness of â¼18 nm using a flat-belt-type high-pressure apparatus. This synthesis procedure presents a promising route to obtain optical-quality BP films, enabling the exploration of integrated optoelectronic device applications such as light-emitting devices and mid-infrared cameras on a chip scale.
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Crystalline symmetries have played a central role in the identification and understanding of quantum materials. Here we investigate whether an amorphous analogue of a well known three-dimensional strong topological insulator has topological properties in the solid state. We show that amorphous Bi2Se3 thin films host a number of two-dimensional surface conduction channels. Our angle-resolved photoemission spectroscopy data are consistent with a dispersive two-dimensional surface state that crosses the bulk gap. Spin-resolved photoemission spectroscopy shows this state has an anti-symmetric spin texture, confirming the existence of spin-momentum locked surface states. We discuss these experimental results in light of theoretical photoemission spectra obtained with an amorphous topological insulator tight-binding model, contrasting it with alternative explanations. The discovery of spin-momentum locked surface states in amorphous materials opens a new avenue to characterize amorphous matter, and triggers the search for an overlooked subset of quantum materials outside of current classification schemes.
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BACKGROUND: People with opioid use disorder (OUD) are at risk of premature death and can benefit from palliative care. We sought to compare palliative care provision for decedents with and without OUD. METHODS: We conducted a cohort study using health administrative databases in Ontario, Canada, to identify people who died between July 1, 2015, and Dec. 31, 2021. The exposure was OUD, defined as having emergency department visits, hospital admissions, or pharmacologic treatments suggestive of OUD within 3 years of death. Our primary outcome was receipt of 1 or more palliative care services during the last 90 days before death. Secondary outcomes included setting, initiation, and intensity of palliative care. We conducted a secondary analysis excluding sudden deaths (e.g., opioid toxicity, injury). RESULTS: Of 679 840 decedents, 11 200 (1.6%) had OUD. Compared with people without OUD, those with OUD died at a younger age and were more likely to live in neighbourhoods with high marginalization indices. We found people with OUD were less likely to receive palliative care at the end of their lives (adjusted relative risk [RR] 0.84, 95% confidence interval [CI] 0.82-0.86), but this difference did not exist after excluding people who died suddenly (adjusted RR 0.99, 95% CI 0.96-1.01). People with OUD were less likely to receive palliative care in clinics and their homes regardless of cause of death. INTERPRETATION: Opioid use disorder can be a chronic, life-limiting illness, and people with OUD are less likely to receive palliative care in communities during the 90 days before death. Health care providers should receive training in palliative care and addiction medicine to support people with OUD.
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Trastornos Relacionados con Opioides , Cuidados Paliativos , Humanos , Ontario/epidemiología , Trastornos Relacionados con Opioides/epidemiología , Trastornos Relacionados con Opioides/mortalidad , Trastornos Relacionados con Opioides/terapia , Masculino , Femenino , Cuidados Paliativos/estadística & datos numéricos , Persona de Mediana Edad , Adulto , Estudios de Cohortes , Anciano , Bases de Datos Factuales , Anciano de 80 o más AñosRESUMEN
BACKGROUND: Advancing health equity requires more contextualised evidence. OBJECTIVES: To synthesise published evidence using an existing framework on the origins of health disparities and determine care-related outcome disparities for residents of long-term care, comparing minoritised populations to the context-specific dominant population. DESIGN: Systematic review. SUBJECTS: Residents of 24-hour long-term care homes. METHODS: The protocol was registered a priori with PROSPERO (CRD42021269489). Literature published between 1 January 2000 and 26 September 2021, was searched, including studies comparing baseline characteristics and outcomes in minoritised versus dominant populations. Dual screening, two-reviewer verification for extraction, and risk of bias assessments were conducted to ensure rigour. Studies were synthesized using a conceptual framework to contextualise evidence according to multi-level factors contributing to the development of care disparities. RESULTS: Twenty-one of 34 included studies demonstrated disparities in care outcomes for minoritised groups compared to majority groups. Thirty-one studies observed differences in individual-level characteristics (e.g. age, education, underlying conditions) upon entry to homes, with several outcome disparities (e.g. restraint use, number of medications) present at baseline and remaining or worsening over time. Significant gaps in evidence were identified, particularly an absence of literature on provider information and evidence on the experience of intersecting minority identities that contribute to care-related outcome disparities in long-term care. CONCLUSION: This review found differences in minoritised populations' care-related outcomes. The findings provide guidance for future health equity policy and research-supporting diverse and intersectional capacity building in long-term care.
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Equidad en Salud , Disparidades en Atención de Salud , Hogares para Ancianos , Cuidados a Largo Plazo , Casas de Salud , Humanos , Anciano , Masculino , FemeninoRESUMEN
Neural networks are promising tools for high-throughput and accurate transmission electron microscopy (TEM) analysis of nanomaterials, but are known to generalize poorly on data that is "out-of-distribution" from their training data. Given the limited set of image features typically seen in high-resolution TEM imaging, it is unclear which images are considered out-of-distribution from others. Here, we investigate how the choice of metadata features in the training dataset influences neural network performance, focusing on the example task of nanoparticle segmentation. We train and validate neural networks across curated, experimentally collected high-resolution TEM image datasets of nanoparticles under various imaging and material parameters, including magnification, dosage, nanoparticle diameter, and nanoparticle material. Overall, we find that our neural networks are not robust across microscope parameters, but do generalize across certain sample parameters. Additionally, data preprocessing can have unintended consequences on neural network generalization. Our results highlight the need to understand how dataset features affect deployment of data-driven algorithms.
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Kousa dogwood (Cornus kousa) is an economically important woody ornamental crop that exhibits creamy, white, pointed bracts in late spring, and reddish to pink drupe fruits in late summer and fall. It bears shiny dark green leaves that become reddish-purple to scarlet in the fall. In August of 2023, 3-year-old container grown C. kousa var. chinensis plants in a commercial nursery in Warren Co., Tennessee, exhibited severe yellowing, dieback and root rot symptoms (Fig. 1a and 1b). Dark brown to black lesions were observed in the root and crown region of the plants. Disease severity was 40% to 60% of root area affected, and disease incidence was approximately 40% of 1,000 plants. Surface-sterilized (10% NaOCl: 1 min) symptomatic root tissues were plated on V8-PARPH and incubated at 25°C. Sparse aerial mycelium, showing a distinct rosette or faint radiate to chrysanthemum colony pattern, was observed within four days of incubation (Fig. 2). All isolates produced ovoid or subglose, papillate, and proliferating sporangia in grass blade water cultures (Dervis et al. 2020). Sporangia measured as 19.18 to 24.80 µm X 18.08 to 22.16 µm (n = 50) with a length/width ratio of 1.06 to 1.11. Zoospores observed were between 7.07 to 9.98 µm in diameter (n = 50). Oogonia and oospores were not produced. The ribosomal internal transcribed spacer (ITS) and large subunit (LSU), as well as mitochondrial cytochrome oxidase subunit II (COX-II) genetic markers were amplified and sequenced using primer pairs ITS1/ITS4 (White et al. 1990), NL1/NL4 (Baten et al. 2014), and cox2-F/cox2-RC4 (Choi et al. 2015), respectively. The ITS, LSU, and COX-II sequences of isolates FBG6343, FBG6344 (ITS: PP458373 and PP461387; LSU: PP461390 and PP461391; COXII: PP477112 and PP477113) were 100% identical to those of MN306118, HQ643386, and MN206732, respectively. Based on the morphology (Nechwatal and Mendgen 2006) and sequence data, the isolates were identified as Phytopythium litorale (Nechw.) Abad, De Cock, Bala, Robideau, Lodhi & Lévesque. The pathogenicity test was performed on 3-year-old C. kousa var. chinensis plants grown in a 3-gal container to fulfill Koch's postulates. Kousa dogwood plants were drench inoculated (800 ml/plant) with a pathogen slurry (two plates of 7-day-old culture/liter) of isolates FBG6343 and FBG6364 (five plants per isolate). Control plants were drenched with agar slurry without the pathogen. The study was conducted in a greenhouse maintained at 21 to 23°C and 70% relative humidity with a 16-h photoperiod and irrigated twice a day for 2 min using an overhead irrigation system. Forty-five days after inoculation, plants showed dieback symptoms, and dark brown lesions developed in the roots of all inoculated plants. Isolates with morphology and sequences identical to those of FBG6343 and FBG6364 were recovered from root tissues of all inoculated plants. All control plants remained symptom-free, and P. litorale was not isolated from the root tissue. Previously, P. litorale was reported to cause disease on apple, kiwi, planatus, and rhododendron (Dervis et al. 2020; Li et al. 2021; Mert et al. 2020; Polat et al. 2023). To our knowledge, this is the first report of P. litorale causing root rot of kousa dogwood in Tennessee and the United States. Identification of this pathogen as the causal agent is crucial to developing timely management practices.
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Halide perovskite is a unique dynamical system, whose structural and chemical processes happening across different timescales have significant impact on its physical properties and device-level performance. However, due to its intrinsic instability, real-time investigation of the structure dynamics of halide perovskite is challenging, which hinders the systematic understanding of the chemical processes in the synthesis, phase transition, and degradation of halide perovskite. Here, we show that atomically thin carbon materials can stabilize ultrathin halide perovskite nanostructures against otherwise detrimental conditions. Moreover, the protective carbon shells enable atomic-level visualization of the vibrational, rotational, and translational movement of halide perovskite unit cells. Albeit atomically thin, protected halide perovskite nanostructures can maintain their structural integrity up to an electron dose rate of 10,000 e-/Å2·s while exhibiting unusual dynamical behaviors pertaining to the lattice anharmonicity and nanoscale confinement. Our work demonstrates an effective method to protect beam-sensitive materials during in situ observation, unlocking new solutions to study new modes of structure dynamics of nanomaterials.
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The eastern redbud (Cercis canadensis L.) is an esthetically and economically important landscape tree with vibrant blossoms and attractive heart-shaped leaves. One-year-old eastern redbud seedlings grown in field condition in two commercial nurseries in Warren Co., Tennessee exhibited severe root rot in October 2021. Dark brown to black lesions and rot were observed in the affected roots (Fig. 1a). Disease severity was 50-75% of root area and disease incidence was approximately 30-40% of 10,000 plants. Surface sterilized (10% NaOCl; 1 min) symptomatic tissues were plated on V8-PARPH and incubated at 25°C. Whitish cottony mycelia with radiate and chrysanthemum flower-like growth patterns were observed within 4 days of incubation. Subglobose papillate sporangia (10.24 to 20.98 µm, n=50), filamentous to globose smooth oogonia, bell-shaped antheridia and spherical zoospores that are characteristic of Phytopythium vexans (de Cock et al. 2015) were observed in older cultures that were subjected to specific growth conditions as previously described by Ghimire & Baysal-Gurel (2023). Pathogen identification was confirmed by extracting total DNA using the DNeasy PowerLyzer Microbial Kit from 7-day-old cultures of isolates FBG0874, FBG1998, FBG2009 grown on V8-PARPH. P. vexans specific LAMP assay was conducted for the rapid molecular screening and confirmation of the isolates (Ghimire et al. 2023). Primer pairs ITS1/ITS4 (White et al. 1990), NL1/NL4 (Baten et al. 2014), Levup and Fm85mod (Robideau et al. 2011) were used to amplify and sequence the internal transcribed spacer (ITS), 28S large subunit (LSU) of ribosomal RNA and the cytochrome c oxidase subunit I (CoxI) of mitochondrial DNA genetic markers, respectively. The sequences (GenBank accession nos. OR204701, OR205212, OR205213: ITS; OR205214, OR205215, OR205216: LSU; OR220805, OR220806, OR220807: CoxI) were 100% similar to ITS, LSU, and CoxI genetic markers of P. vexans isolates in the NCBI database (MK011121: ITS, KX092469: LSU and KT692908: CoxI). Pathogenicity tests were performed on one-year-old eastern redbud seedlings grown in 1 gal containers to fulfill Koch's postulate. Eastern redbud seedlings were drench inoculated (150 ml/plant) with pathogen slurry (two plates of 7-day-old culture/liter) (Panth et al. 2021) of isolates FBG0874, FBG1998, and FBG2009 (five plants/isolate). Control plants were drenched with agar slurry without pathogen. The study was conducted in a greenhouse maintained at 21 to 23°C, 70%RH, with 16-h photoperiod and irrigated twice a day for 2 min using an overhead irrigation system. Fourteen days after inoculation dark brown to black lesions developed in the root of all inoculated plants that were identical to the symptoms observed in the original samples (Fig. 1b), while the roots of non-inoculated plants remained asymptomatic (Fig. 1c). Isolates resembling P. vexans morphological characteristics were recovered from inoculated plants, and their identity was confirmed as P. vexans using LAMP assay. P. vexans has been previously reported to cause root and crown rot in flowering cherry, ginkgo, and red maple in Tennessee (Baysal-Gurel et al. 2021, Panth et al. 2021). To our knowledge, this is the first report of P. vexans causing root rot of eastern redbud in Tennessee and the United States. Identification of this pathogen as the causal agent is important in designing and implementing effective management practices to mitigate this threat to redbud production.
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Chronic myeloid leukaemia (CML) arises after transformation of a haemopoietic stem cell (HSC) by the protein-tyrosine kinase BCR-ABL. Direct inhibition of BCR-ABL kinase has revolutionized disease management, but fails to eradicate leukaemic stem cells (LSCs), which maintain CML. LSCs are independent of BCR-ABL for survival, providing a rationale for identifying and targeting kinase-independent pathways. Here we show--using proteomics, transcriptomics and network analyses--that in human LSCs, aberrantly expressed proteins, in both imatinib-responder and non-responder patients, are modulated in concert with p53 (also known as TP53) and c-MYC regulation. Perturbation of both p53 and c-MYC, and not BCR-ABL itself, leads to synergistic cell kill, differentiation, and near elimination of transplantable human LSCs in mice, while sparing normal HSCs. This unbiased systems approach targeting connected nodes exemplifies a novel precision medicine strategy providing evidence that LSCs can be eradicated.
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Leucemia Mielógena Crónica BCR-ABL Positiva/metabolismo , Leucemia Mielógena Crónica BCR-ABL Positiva/patología , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Proteínas Proto-Oncogénicas c-myc/antagonistas & inhibidores , Proteína p53 Supresora de Tumor/antagonistas & inhibidores , Acetamidas/farmacología , Acetamidas/uso terapéutico , Animales , Antígenos CD34/metabolismo , Azepinas/farmacología , Azepinas/uso terapéutico , Muerte Celular/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Proteínas de Unión al ADN/metabolismo , Femenino , Proteínas de Fusión bcr-abl/metabolismo , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/efectos de los fármacos , Células Madre Hematopoyéticas/metabolismo , Humanos , Mesilato de Imatinib/farmacología , Mesilato de Imatinib/uso terapéutico , Imidazolinas/farmacología , Imidazolinas/uso terapéutico , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Masculino , Ratones , Proteínas de Neoplasias/metabolismo , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/trasplante , Proteómica , Proteínas Proto-Oncogénicas c-myc/deficiencia , Proteínas Proto-Oncogénicas c-myc/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo , Reproducibilidad de los Resultados , Transducción de Señal/efectos de los fármacos , Transcriptoma , Proteína p53 Supresora de Tumor/deficiencia , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismoRESUMEN
Understanding the structure of materials is crucial for engineering devices and materials with enhanced performance. Four-dimensional scanning transmission electron microscopy (4D-STEM) is capable of mapping nanometer-scale local crystallographic structure over micron-scale field of views. However, 4D-STEM datasets can contain tens of thousands of images from a wide variety of material structures, making it difficult to automate detection and classification of structures. Traditional automated analysis pipelines for 4D-STEM focus on supervised approaches, which require prior knowledge of the material structure and cannot describe anomalous or deviant structures. In this article, a pipeline for engineering 4D-STEM feature representations for unsupervised clustering using non-negative matrix factorization (NMF) is introduced. Each feature is evaluated using NMF and results are presented for both simulated and experimental data. It is shown that some data representations more reliably identify overlapping grains. Additionally, real space refinement is applied to identify spatially distinct sample regions, allowing for size and shape analysis to be performed. This work lays the foundation for improved analysis of nanoscale structural features in materials that deviate from expected crystallographic arrangement using 4D-STEM.
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Obsidian is volcanic glass that results from the rapid cooling of silica-rich melt. Nanoscale crystallites precipitate out of the melt prior to solidification and remain embedded in the amorphous matrix. These crystallites provide information on the flow kinetics and composition of the melt. Due to the sparsity and size of nanolites, studies often focus on supramicron crystallites. This research takes advantage of the conchoidal fracture of obsidian by knapping samples with nanometer-thin edges for transmission electron microscopy characterization. Nanolites in the amorphous matrix are studied using energy-dispersive spectroscopy (EDS) and electron diffraction. Certain alkali and alkaline-earth cations exhibit patterns of depletion near Fe-oxide nanolites. EDS is used to identify nanolites and variations in the composition of the matrix. Parallel beam diffraction and radial distribution function analysis of nearest-neighbor distances determine average bond lengths in the matrix near nanolites, showing that nanolites influence the nearby short-range ordering and atomic character of the matrix. Analysis reveals decreased mean nearest-neighbor distances in the matrix adjacent to nanolites compared to the bulk. Our methods exhibit the required sensitivity to detect variations in the composition and structure near nanolites, and our findings indicate that obsidian nanolites contribute to quantifiable localized changes in the amorphous structure.
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Trained neural networks are promising tools to analyze the ever-increasing amount of scientific image data, but it is unclear how to best customize these networks for the unique features in transmission electron micrographs. Here, we systematically examine how neural network architecture choices affect how neural networks segment, or pixel-wise separate, crystalline nanoparticles from amorphous background in transmission electron microscopy (TEM) images. We focus on decoupling the influence of receptive field, or the area of the input image that contributes to the output decision, from network complexity, which dictates the number of trainable parameters. For low-resolution TEM images which rely on amplitude contrast to distinguish nanoparticles from background, we find that the receptive field does not significantly influence segmentation performance. On the other hand, for high-resolution TEM images which rely on both amplitude and phase-contrast changes to identify nanoparticles, receptive field is an important parameter for increased performance, especially in images with minimal amplitude contrast. Rather than depending on atom or nanoparticle size, the ideal receptive field seems to be inversely correlated to the degree of nanoparticle contrast in the image. Our results provide insight and guidance as to how to adapt neural networks for applications with TEM datasets.
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Crystalline materials used in technological applications are often complex assemblies composed of multiple phases and differently oriented grains. Robust identification of the phases and orientation relationships from these samples is crucial, but the information extracted from the diffraction condition probed by an electron beam is often incomplete. We have developed an automated crystal orientation mapping (ACOM) procedure which uses a converged electron probe to collect diffraction patterns from multiple locations across a complex sample. We provide an algorithm to determine the orientation of each diffraction pattern based on a fast sparse correlation method. We demonstrate the speed and accuracy of our method by indexing diffraction patterns generated using both kinematical and dynamical simulations. We have also measured orientation maps from an experimental dataset consisting of a complex polycrystalline twisted helical AuAgPd nanowire. From these maps we identify twin planes between adjacent grains, which may be responsible for the twisted helical structure. All of our methods are made freely available as open source code, including tutorials which can be easily adapted to perform ACOM measurements on diffraction pattern datasets.
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This study sought to identify barriers and facilitators to successful smart insulin pen (SIP) use and gauge prescribing practices and integration into clinical practice by assessing provider and care team perspectives at participating endocrinology clinics within the T1D Exchange Quality Improvement Collaborative. The identified provider-related, patient-related, and clinic- and operational-level barriers and facilitators varied based on clinic knowledge, capacity, and resources. High-impact barriers included insurance coverage and prescribing processes; high-impact facilitators included improved diabetes clinic visit quality and use of SIPs as an alternative to insulin pump therapy. Findings indicated the need for provider and care team education and training on proper SIP features, use, and prescribing.
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This article describes how the T1D Exchange Quality Improvement Collaborative leverages an innovative web platform, the QI Portal, to gather and store electronic medical record (EMR) data to promote benchmarking and population health improvement in a type 1 diabetes learning health system. The authors explain the value of the QI Portal, the process for mapping center-level data from EMRs using standardized data specifications, and the QI Portal's unique features for advancing population health.
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Importance: Extracorporeal membrane oxygenation (ECMO) is used as temporary cardiorespiratory support in critically ill patients, but little is known regarding long-term psychiatric sequelae among survivors after ECMO. Objective: To investigate the association between ECMO survivorship and postdischarge mental health diagnoses among adult survivors of critical illness. Design, Setting, and Participants: Population-based retrospective cohort study in Ontario, Canada, from April 1, 2010, through March 31, 2020. Adult patients (N=4462; age ≥18 years) admitted to the intensive care unit (ICU), and surviving to hospital discharge were included. Exposures: Receipt of ECMO. Main Outcomes and Measures: The primary outcome was a new mental health diagnosis (a composite of mood disorders, anxiety disorders, posttraumatic stress disorder; schizophrenia, other psychotic disorders; other mental health disorders; and social problems) following discharge. There were 8 secondary outcomes including incidence of substance misuse, deliberate self-harm, death by suicide, and individual components of the composite primary outcome. Patients were compared with ICU survivors not receiving ECMO using overlap propensity score-weighted cause-specific proportional hazard models. Results: Among 642 survivors who received ECMO (mean age, 50.7 years; 40.7% female), median length of follow-up was 730 days; among 3820 matched ICU survivors who did not receive ECMO (mean age, 51.0 years; 40.0% female), median length of follow-up was 1390 days. Incidence of new mental health conditions among survivors who received ECMO was 22.1 per 100-person years (95% confidence interval [CI] 19.5-25.1), and 14.5 per 100-person years (95% CI, 13.8-15.2) among non-ECMO ICU survivors (absolute rate difference of 7.6 per 100-person years [95% CI, 4.7-10.5]). Following propensity weighting, ECMO survivorship was significantly associated with an increased risk of new mental health diagnosis (hazard ratio [HR] 1.24 [95% CI, 1.01-1.52]). There were no significant differences between survivors who received ECMO vs ICU survivors who did not receive ECMO in substance misuse (1.6 [95% CI, 1.1 to 2.4] per 100 person-years vs 1.4 [95% CI, 1.2 to 1.6] per 100 person-years; absolute rate difference, 0.2 per 100 person-years [95% CI, -0.4 to 0.8]; HR, 0.86 [95% CI, 0.48 to 1.53]) or deliberate self-harm (0.4 [95% CI, 0.2 to 0.9] per 100 person-years vs 0.3 [95% CI, 0.2 to 0.3] per 100 person-years; absolute rate difference, 0.1 per 100 person-years [95% CI, -0.2 to 0.4]; HR, 0.68 [95% CI, 0.21 to 2.23]). There were fewer than 5 total cases of death by suicide in the entire cohort. Conclusions and Relevance: Among adult survivors of critical illness, receipt of ECMO, compared with ICU hospitalization without ECMO, was significantly associated with a modestly increased risk of new mental health diagnosis or social problem diagnosis after discharge. Further research is necessary to elucidate the potential mechanisms underlying this relationship.
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Oxigenación por Membrana Extracorpórea , Trastornos Relacionados con Sustancias , Adulto , Humanos , Femenino , Persona de Mediana Edad , Adolescente , Masculino , Enfermedad Crítica/terapia , Oxigenación por Membrana Extracorpórea/efectos adversos , Salud Mental , Estudios Retrospectivos , Alta del Paciente , Cuidados Posteriores , Sobrevivientes/psicología , Evaluación de Resultado en la Atención de Salud , Ontario/epidemiologíaRESUMEN
Phase-separation is commonly observed in multimetallic nanomaterials, yet it is not well understood how immiscible elements distribute in a thermodynamically stable nanoparticle. Herein, we studied the phase-separation of Au and Rh in nanoparticles using electron microscopy and tomography techniques. The nanoparticles were thermally annealed to form thermodynamically stable structures. HAADF-STEM and EDS characterizations reveal that Au and Rh segregate into two domains while their miscibility is increased. Using aberration-corrected HAADF-STEM and atomic electron tomography, we show that the increased solubility of Au in Rh is achieved by forming Au clusters and single atoms inside the Rh domains and on the Rh surface. Furthermore, based on the three-dimensional reconstruction of a AuRh nanoparticle, we can visualize the uneven interface that is embedded in the nanoparticle. The results advance our understanding on the nanoscale thermodynamic behavior of metal mixtures, which is crucial for the optimization of multimetallic nanostructures for many applications.
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Nanopartículas , Nanoestructuras , Microscopía Electrónica , Solubilidad , TermodinámicaRESUMEN
BACKGROUND: We aim to describe the occurrence of red blood cell transfusion and associated predictive factors and outcomes among patients referred for palliative care. STUDY DESIGN AND METHODS: This retrospective cohort study used linked health administrative data of adults referred for palliative care at an academic hospital from 2014 to 2018. Multivariable regression models were employed to evaluate patient characteristics associated with transfusion and the relationship between transfusion status and location of death. Survival analyses were performed using log-rank tests and Cox proportional hazards modeling. RESULTS: Of 6980 evaluated patients, 885 (12.7%) were transfused following palliative care consultation. Covariate factors associated with transfusion included younger age, higher performance status, lower baseline hemoglobin, and a diagnosis of hematologic malignancy (OR = 2.97, 95% CI 2.20-4.01) or solid organ tumor (OR = 1.37, 95% CI 1.10-1.71) vs. noncancer diagnosis. Median survival from palliative care consultation was 19 (IQR 5-75) days; 83 (32-305) days in those transfused and 15 (4-57) days in the nontransfused group (p < .0001). Median survival following transfusion was 56 (19-200) days. Solid organ tumor diagnosis was independently associated with poor survival (HR = 1.7, 95% CI 1.39-2.09 vs. non-cancer diagnosis). Among individuals who survived ≥30 days, transfusion was associated with a higher likelihood of death in hospital (OR = 2.15, 95% CI 1.71-2.70 vs. home/subacute setting). DISCUSSION: Transfusions commonly occurred in patients receiving palliative care, associated with cancer diagnoses and favorable baseline prognostic factors. Poor survival following transfusion, particularly in solid organ tumor patients, and the twofold likelihood of death in hospital associated with this intervention have important implications in prescribing transfusion for this population.