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The mergers of binary compact objects such as neutron stars and black holes are of central interest to several areas of astrophysics, including as the progenitors of gamma-ray bursts (GRBs)1, sources of high-frequency gravitational waves (GWs)2 and likely production sites for heavy-element nucleosynthesis by means of rapid neutron capture (the r-process)3. Here we present observations of the exceptionally bright GRB 230307A. We show that GRB 230307A belongs to the class of long-duration GRBs associated with compact object mergers4-6 and contains a kilonova similar to AT2017gfo, associated with the GW merger GW170817 (refs. 7-12). We obtained James Webb Space Telescope (JWST) mid-infrared imaging and spectroscopy 29 and 61 days after the burst. The spectroscopy shows an emission line at 2.15 microns, which we interpret as tellurium (atomic mass A = 130) and a very red source, emitting most of its light in the mid-infrared owing to the production of lanthanides. These observations demonstrate that nucleosynthesis in GRBs can create r-process elements across a broad atomic mass range and play a central role in heavy-element nucleosynthesis across the Universe.
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Tidal disruption events (TDEs) are bursts of electromagnetic energy that are released when supermassive black holes at the centres of galaxies violently disrupt a star that passes too close1. TDEs provide a window through which to study accretion onto supermassive black holes; in some rare cases, this accretion leads to launching of a relativistic jet2-9, but the necessary conditions are not fully understood. The best-studied jetted TDE so far is Swift J1644+57, which was discovered in γ-rays, but was too obscured by dust to be seen at optical wavelengths. Here we report the optical detection of AT2022cmc, a rapidly fading source at cosmological distance (redshift z = 1.19325) the unique light curve of which transitioned into a luminous plateau within days. Observations of a bright counterpart at other wavelengths, including X-ray, submillimetre and radio, supports the interpretation of AT2022cmc as a jetted TDE containing a synchrotron 'afterglow', probably launched by a supermassive black hole with spin greater than approximately 0.3. Using four years of Zwicky Transient Facility10 survey data, we calculate a rate of [Formula: see text] per gigapascals cubed per year for on-axis jetted TDEs on the basis of the luminous, fast-fading red component, thus providing a measurement complementary to the rates derived from X-ray and radio observations11. Correcting for the beaming angle effects, this rate confirms that approximately 1 per cent of TDEs have relativistic jets. Optical surveys can use AT2022cmc as a prototype to unveil a population of jetted TDEs.
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This work reveals that photoanodes based on TiNb2 O7 (TNO) powder show remarkable water-oxidation properties including nearly ideal charge-transfer and charge-injection efficiencies. Furthermore, using a simplified photoanode construction and carefully surveying the structural and morphological characteristics of oriented and polycrystalline thin films and powder-based samples revealed that the water-splitting kinetics of TNO is negligibly effected by surface morphology; instead, internal grain boundaries likely play a driving role. The current powder-based TNO photoanodes exhibit ideal water-oxidation kinetics and oxidize water at minimal applied biases under illumination; consequently, TNO exhibits an early onset photocurrent voltage (0.4â V vs. RHE) that rivals that of other state-of-the-art photoanode materials.
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Magnetic iron oxide/mesoporous silica nanocomposites consisting of iron oxide nanoparticles embedded within mesoporous silica (MCM-41) and modified with aminopropyl functional groups were prepared for application to Cr(III) adsorption followed by magnetic recovery of the nanocomposite materials from aqueous solution. The composite materials were extensively characterized using physicochemical techniques, such as powder X-ray diffraction, thermogravimetric and elemental analysis, nitrogen adsorption, and zeta potential measurements. For aqueous Cr(III) at pH 5.4, the iron oxide/mesoporous silica nanocomposite exhibited a superior equilibrium adsorption capacity of 0.71 mmol/g, relative to 0.17 mmol/g for unmodified mesoporous silica. The aminopropyl-functionalized iron oxide/mesoporous silica nanocomposites displayed an equilibrium adsorption capacity of 2.08 mmol/g, the highest adsorption capacity for Cr(III) of all the materials evaluated in this study. Energy-dispersive spectroscopy (EDS) with transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) experiments provided insight into the chemical nature of the adsorbed chromium species.
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Cromo/química , Compuestos Férricos/química , Nanocompuestos/química , Dióxido de Silicio/química , Adsorción , Tamaño de la Partícula , Porosidad , Propiedades de SuperficieRESUMEN
The epidermal growth factor receptor (EGFR) is a receptor tyrosine kinase with important roles in many cellular processes as well as in cancer and other diseases. EGF binding promotes EGFR dimerization and autophosphorylation through interactions that are well understood structurally. How these dimers relate to higher-order EGFR oligomers seen in cell membranes, however, remains unclear. Here, we used single-particle tracking (SPT) and Förster resonance energy transfer imaging to examine how each domain of EGFR contributes to receptor oligomerization and the rate of receptor diffusion in the cell membrane. Although the extracellular region of EGFR is sufficient to drive receptor dimerization, we find that the EGF-induced EGFR slowdown seen by SPT requires higher-order oligomerization-mediated in part by the intracellular tyrosine kinase domain when it adopts an active conformation. Our data thus provide important insight into the interactions required for higher-order EGFR assemblies involved in EGF signaling.
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Factor de Crecimiento Epidérmico , Receptores ErbB , Factor de Crecimiento Epidérmico/farmacología , Factor de Crecimiento Epidérmico/metabolismo , Receptores ErbB/metabolismo , Membrana Celular/metabolismo , Fosforilación , Transducción de SeñalRESUMEN
The epidermal growth factor receptor (EGFR) is a receptor tyrosine kinase (RTK) with important roles in many cellular processes as well as cancer and other diseases. EGF binding promotes EGFR dimerization and autophosphorylation through interactions that are well understood structurally. However, it is not clear how these dimers relate to higher-order EGFR oligomers detected at the cell surface. We used single-particle tracking (SPT) and Förster resonance energy transfer (FRET) imaging to examine how each domain within EGFR contributes to receptor dimerization and the rate of its diffusion in the cell membrane. We show that the EGFR extracellular region is sufficient to drive receptor dimerization, but that the EGF-induced EGFR slow-down seen by SPT requires formation of higher order oligomers, mediated in part by the intracellular tyrosine kinase domain - but only when in its active conformation. Our data thus provide important insight into higher-order EGFR interactions required for EGF signaling.
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OBJECTIVE: This article focuses on wraparound as an example of a team planning process, and uses data from several sources to reflect on questions about whether-and under what conditions-collaborative teams are successful in engaging young people-and their caregivers-in planning. METHODS: We used data collected in three studies to address our research questions. The first data set comes from a study on wraparound service planning in Nevada. We examined data collected from 23 matched pairs of caregivers and youth at 6 months after wraparound planning began. Our second data set came from a national study of 41 local wraparound programs throughout the United States. Our analyses use data from 366 matched pairs of caregivers/youth. The third dataset comes from the pilot test of the Achieve My Plan! intervention. Data was gathered from eight teams before and after the intervention was implemented. RESULTS: Taken together, the findings suggest that teams' success in managing caregiver and adolescent perspectives simultaneously during care and treatment planning is more strongly related to the quality of the team process than to youth age. CONCLUSIONS AND IMPLICATIONS FOR PRACTICE: Through attention to youth engagement, preparation, and tem process, it appears possible to increase meaningful youth participation in planning without sacrificing caregiver satisfaction with the team experience.
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Cuidadores , Redes Comunitarias/normas , Trastornos Mentales/rehabilitación , Planificación de Atención al Paciente/normas , Grupo de Atención al Paciente/organización & administración , Adolescente , Conducta del Adolescente , Conducta Cooperativa , Femenino , Humanos , Masculino , Nevada , Evaluación de Resultado en la Atención de Salud , Participación del Paciente/métodos , Participación del Paciente/psicología , Satisfacción del Paciente , Evaluación de Programas y Proyectos de Salud , Estados UnidosRESUMEN
Acinic cell carcinoma (AcCC) is a morphologically distinctive salivary gland malignancy often associated with chromosome rearrangements leading to overexpression of the NR4A3 transcription factor. However, little is known about how NR4A3 contributes to AcCC biology. Detailed RNA-sequencing of 21 archived AcCC samples revealed fusion reads arising from recurrent t(4;9), t(9;12), t(8;9) or t(2;4) chromosomal translocations, which positioned highly active enhancers adjacent to the promoter of the NR4A3 gene or the closely related NR4A2 gene, resulting in their aberrant overexpression. Transcriptome analyses revealed several distinct subgroups of AcCC tumors, including a subgroup that overexpressed both NR4A3 and MSANTD3. A poor survival subset of the tumors with high-grade transformation expressed NR4A3 and POMC as well as MYB, an oncogene that is the major driver in a different type of salivary gland tumor, adenoid cystic carcinoma. The combination of NR4A3 and MYB showed cooperativity in regulating a distinct set of genes. In addition, the ligand binding domain of NR4A3 directly bound the Myb DNA binding domain. Transformation assays indicated that, while overexpressed NR4A3 was sufficient to generate transformed colonies, the combination of NR4A3 plus Myb was more potent, leading to anchorage-independent growth and increased cellular invasiveness. The results confirm that NR4A3 and NR4A2 are the main driver genes of AcCC and suggest that concurrent overexpression of NR4A3 and MYB defines a subset of AcCC patients with high-grade transformation that display exceptionally poor outcome.
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In this work we lay out design guidelines for catalytically more efficient organic photocathodes achieving stable hydrogen production in neutral pH. We propose an organic photocathode architecture employing a NiO hole selective layer, a PCDTBT:PCBM bulk heterojunction, a compact TiO2 electron selective contact and a RuO2 nanoparticle catalyst. The role of each layer is discussed in terms of durability and function. With this strategically designed organic photocathode we obtain stable photocurrent densities for over 5 h and discuss routes for further performance improvement.
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OBJECTIVE: The recent introduction of substance abuse treatment measures to the Health Plan Employer and Data Information Set (HEDIS) highlights the importance of this area for managed care organizations (MCOs). Particularly challenging are members first diagnosed in an emergency department (ED). STUDY DESIGN: Retrospective claims analysis. METHODS: Claims were abstracted for all members who used an ED in 2004 for a diagnosis of substance abuse in a large commercial MCO. General linear models were used to estimate the association between receiving follow-up care within 14 and 60 days and sex, age, type of primary diagnosis, substance abused, and level of use. RESULTS: Of the 1235 patients who visited an ED with a diagnosis of substance abuse, 13% received follow-up substance abuse services within 14 days of their ED visit. An additional 36% of patients had an outpatient service that did not code a substance abuse diagnosis within 2 weeks of an ED visit. The diagnosis breakdown of patients' primary diagnoses was 28% substance use, 13% mental health issues, and 59% nonpsychiatric (medical) disorders. The multivariable regression analyses revealed having a nonpsychiatric (medical) primary diagnosis was the strongest predictor of not receiving follow-up care (relative risk = 0.51) at 14 days compared with patients who had a mental health diagnosis. CONCLUSIONS: Training ED staff and nonbehavioral health outpatient providers in treatment follow-up for substance abuse may improve the quality of care for patients. Encouraging providers to code for substance abuse when treatment or counseling is delivered would improve health plan HEDIS scores. Interventions may be needed for frequent ED users with substance abuse.