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The first observations of JWST have revolutionized our understanding of the Universe by identifying for the first time galaxies at z â¼ 13 1-3. In addition, the discovery of many luminous galaxies at Cosmic Dawn ( z > 10 ) has suggested that galaxies developed rapidly, in apparent tension with many standard models4-8. However, most of these galaxies lack spectroscopic confirmation, so their distances and properties are uncertain. We present JADES JWST/NIRSpec spectroscopic confirmation of two luminous galaxies at redshifts of z = 14.32 - 0.20 + 0.08 and z = 13.90 ± 0.17 . The spectra reveal ultraviolet continua with prominent Lyman- α breaks but no detected emission lines. This discovery proves that luminous galaxies were already in place 300 million years after the Big Bang and are more common than what was expected before JWST. The most distant of the two galaxies is unexpectedly luminous and is spatially resolved with a radius of 260 parsecs. Considering also the very steep ultraviolet slope of the second galaxy, we conclude that both are dominated by stellar continuum emission, showing that the excess of luminous galaxies in the early Universe cannot be entirely explained by accretion onto black holes. Galaxy formation models will need to address the existence of such large and luminous galaxies so early in cosmic history.
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Large-scale outflows driven by supermassive black holes are thought to have a fundamental role in suppressing star formation in massive galaxies. However, direct observational evidence for this hypothesis is still lacking, particularly in the young universe where star-formation quenching is remarkably rapid1-3, thus requiring effective removal of gas4 as opposed to slow gas heating5,6. Although outflows of ionized gas are frequently detected in massive distant galaxies7, the amount of ejected mass is too small to be able to suppress star formation8,9. Gas ejection is expected to be more efficient in the neutral and molecular phases10, but at high redshift these have only been observed in starbursts and quasars11,12. Here we report JWST spectroscopy of a massive galaxy experiencing rapid quenching at a redshift of 2.445. We detect a weak outflow of ionized gas and a powerful outflow of neutral gas, with a mass outflow rate that is sufficient to quench the star formation. Neither X-ray nor radio activity is detected; however, the presence of a supermassive black hole is suggested by the properties of the ionized gas emission lines. We thus conclude that supermassive black holes are able to rapidly suppress star formation in massive galaxies by efficiently ejecting neutral gas.
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Local and low-redshift (z < 3) galaxies are known to broadly follow a bimodal distribution: actively star-forming galaxies with relatively stable star-formation rates and passive systems. These two populations are connected by galaxies in relatively slow transition. By contrast, theory predicts that star formation was stochastic at early cosmic times and in low-mass systems1-4. These galaxies transitioned rapidly between starburst episodes and phases of suppressed star formation, potentially even causing temporary quiescence-so-called mini-quenching events5,6. However, the regime of star-formation burstiness is observationally highly unconstrained. Directly observing mini-quenched galaxies in the primordial Universe is therefore of utmost importance to constrain models of galaxy formation and transformation7,8. Early quenched galaxies have been identified out to redshift z < 5 (refs. 9-12) and these are all found to be massive (Mâ > 1010 Mâ) and relatively old. Here we report a (mini-)quenched galaxy at z = 7.3, when the Universe was only 700 Myr old. The JWST/NIRSpec spectrum is very blue (U-V = 0.16 ± 0.03 mag) but exhibits a Balmer break and no nebular emission lines. The galaxy experienced a short starburst followed by rapid quenching; its stellar mass (4-6 × 108 Mâ) falls in a range that is sensitive to various feedback mechanisms, which can result in perhaps only temporary quenching.
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Galaxias , Factores de Tiempo , Estrellas Celestiales , Medio Ambiente Extraterrestre/químicaRESUMEN
Large dust reservoirs (up to approximately 108 Mâ) have been detected1-3 in galaxies out to redshift z ≃ 8, when the age of the Universe was only about 600 Myr. Generating substantial amounts of dust within such a short timescale has proven challenging for theories of dust formation4,5 and has prompted the revision of the modelling of potential sites of dust production6-8, such as the atmospheres of asymptotic giant branch stars in low-metallicity environments, supernova ejecta and the accelerated growth of grains in the interstellar medium. However, degeneracies between different evolutionary pathways remain when the total dust mass of galaxies is the only available observable. Here we report observations of the 2,175 Å dust attenuation feature, which is well known in the Milky Way and galaxies at z â² 3 (refs. 9-11), in the near-infrared spectra of galaxies up to z ≃ 7, corresponding to the first billion years of cosmic time. The relatively short timescale implied for the formation of carbonaceous grains giving rise to this feature12 suggests a rapid production process, possibly in Wolf-Rayet stars or supernova ejecta.
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The effects of stress and parenting on 1-year trajectories of physiological emotion regulation capacity among adolescents were examined. Consistent with the vulnerability-stress and allostatic load models, stress (chronic family and marital) was hypothesized to be associated with less favorable trajectories of basal respiratory sinus arrhythmia (RSA) over 1 year. This relationship was further hypothesized to be moderated by parenting practices (warmth, neglect, and rejection) and adolescent sex. Participants included 150 adolescents (51.3% female), 11-15 years of age (M = 13.04, SD = 0.89). Basal RSA and stress were assessed four times across 1 year. Results indicated a significant decrease in RSA over the course of 1 year (ß = -0.15, p = .010). Warm parenting style was associated with lower RSA in environments of low marital stress and was also related with higher RSA in environments of high marital stress (ß = 0.86, p = .021). Rejecting parenting styles were associated with higher RSA in environments of low family stress and lower RSA in environments of high family stress (ß = -0.60, p = .014). These findings may be explained by the Yerkes-Dodson law of optimal stress, suggesting that sufficient environmental challenge is needed to catalyze regulatory development.
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Regulación Emocional , Arritmia Sinusal Respiratoria , Adolescente , Arritmias Cardíacas , Conflicto Familiar , Femenino , Humanos , Masculino , Responsabilidad Parental/psicología , Arritmia Sinusal Respiratoria/fisiologíaRESUMEN
Gravitational interactions between the Large Magellanic Cloud (LMC) and the stellar and dark matter halo of the Milky Way are expected to give rise to disequilibrium phenomena in the outer Milky Way1-7. A local wake is predicted to trail the orbit of the LMC, and a large-scale overdensity is predicted to exist across a large area of the northern Galactic hemisphere. Here we report the detection of both the local wake and northern overdensity (hereafter the 'collective response') in a map of the Galaxy based on 1,301 stars at Galactocentric distances between 60 and 100 kiloparsecs. The location of the wake is in good agreement with an N-body simulation that includes the dynamical effect of the LMC on the Milky Way halo. The density contrast of the wake and collective response are stronger in the data than in the simulation. The detection of a strong local wake is independent evidence that the Magellanic clouds are on their first orbit around the Milky Way. The wake traces the path of the LMC, which will provide insight into the orbit of the LMC, which in turn is a sensitive probe of the mass of the LMC and the Milky Way. These data demonstrate that the outer halo is not in dynamical equilibrium, as is often assumed. The morphology and strength of the wake could be used to test the nature of dark matter and gravity.
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A western Massachusetts county jail began initiating extended-release naltrexone (XR-NTX) prior to release from incarceration and linking participants to community treatment providers upon release. Program barriers prevented the start of XR-NTX prior to release for a subset. METHODS: This report consists of the initial 67 jail releasees with opioid dependence, 47 who received XR-NTX before release, and 20 after release. Utility of the program was assessed by determining medication addiction treatment (MAT) retention rates at 4, 8, and 24 weeks. RESULTS: Forty-seven commenced XR-NTX approximately 7 days prior to release, and 20 were referred to commence XR-NTX at outpatient treatment centers. Rate of retention at week 4 was higher in group with treatment initiation prior to release as compared to those started in community: week 4: 55% (24 XR-NTX+2 agonist MAT out of 47) versus 25% (4 XR-NTX+1 agonist MAT out of 20) (p=0.03); week 8: 36% (13 XR-NTX+4 agonist) versus 25% (3 XR-NTX+2 agonist) (p=0.41); week 24: 21% (6 XR-NTX+4 agonist) versus 15% (1 XR-NTX+2 agonist) (p=0.74). Three patients died, all in the pre-release group, all from overdose at 3-5months after release and 2.5 or more months after stopping XR-NTX, compared to none of 20 in community group (p=0.55). Limitations include that cohorts were non-random and observational; substance use could not be consistently determined; and overdose deaths in MA occurred partly in clusters, limiting historical comparisons. CONCLUSIONS: Receiving XR-NTX prior to jail release for opioid use disorder appears to increase the treatment retention rate as compared to commencing after release. The treatment attrition and striking rate of overdose deaths are concerning, and support expanded availability of opioid agonist treatments prior to release and other evidence-based supports and retention strategies in the community.
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Naltrexona/uso terapéutico , Antagonistas de Narcóticos/uso terapéutico , Trastornos Relacionados con Opioides/tratamiento farmacológico , Prisiones , Adulto , Atención Ambulatoria/métodos , Preparaciones de Acción Retardada , Sobredosis de Droga/mortalidad , Femenino , Humanos , Inyecciones Intramusculares , Masculino , Massachusetts , Estudios ProspectivosRESUMEN
Assessment, treatment, and management of sport-related concussions are a widely recognized public health issue. Although several neuropsychological and motor assessment tools have been developed and implemented for sports teams at various levels and ages, the sensitivity of these tests has yet to be validated with more objective measures to make return-to-play (RTP) decisions more confidently. The present study sought to analyze the residual effect of concussions on a sample of adolescent athletes who sustained one or more previous concussions compared to those who had no concussion history. For this purpose, a wide variety of assessment tools containing both neurocognitive and electroencephalogram (EEG) elements were used. All clinical testing and EEG were repeated at 8 months, 10 months, and 12 months post-injury for both healthy and concussed athletes. The concussed athletes performed poorer than healthy athletes on processing speed and impulse control subtest of neurocognitive test on month 8, but no alterations were marked in terms of visual and postural stability. EEG analysis revealed significant differences in brain activities of concussed athletes through all three intervals. These long-term neurocognitive and EEG deficits found from this ongoing sport-related concussion study suggest that the post-concussion physiological deficits may last longer than the observed clinical recovery.
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Traumatismos en Atletas/fisiopatología , Conmoción Encefálica/fisiopatología , Cognición/fisiología , Electroencefalografía , Adolescente , Atletas , Traumatismos en Atletas/etiología , Conmoción Encefálica/etiología , Humanos , Masculino , Pruebas NeuropsicológicasRESUMEN
OBJECTIVE: To report a probable case of vasospastic angina after administration of dihydroergotamine mesylate in a patient without coronary artery disease. CASE SUMMARY: A 49-year-old woman with relapsing/remitting multiple sclerosis was admitted for severe headache and pain crisis. She received a single dose of intravenous dihydroergotamine and, within 30 minutes, experienced chest pain, nausea, and vomiting. No changes on electrocardiogram were noted, but cardiac enzyme levels were elevated. Brief episodes of chest pain persisted for several days and resolved spontaneously before the woman's discharge. She had several cardiac risk factors, including cigarette smoking, hypertension, and a family history of coronary artery disease, but cardiac catheterization on hospital day 5 revealed no underlying coronary artery disease. DISCUSSION: Although cardiovascular adverse reactions have been reported with ergotamine tartrate, dihydroergotamine has rarely been linked with such reactions, including coronary vasospasm and myocardial infarction. Prescribing information for dihydroergotamine cautions against its use in patients with coronary artery disease or risk factors for underlying coronary artery disease without a cardiac workup before initiation of therapy. This patient had several cardiac risk factors, but cardiac catheterization revealed no underlying coronary artery disease. Concomitant verapamil therapy for hypertension did not prevent the vasospastic effects of dihydroergotamine. The Naranjo probability scale revealed a probable adverse reaction of vasospastic angina associated with dihydroergotamine. CONCLUSIONS: Health-care professionals should be aware of the possibility for vasospastic angina in patients receiving dihydroergotamine who have no underlying coronary artery disease. Prescribing information should be closely followed.
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Angina de Pecho/inducido químicamente , Bloqueadores de los Canales de Calcio/efectos adversos , Vasoespasmo Coronario/inducido químicamente , Dihidroergotamina/efectos adversos , Vasoconstrictores/efectos adversos , Bloqueadores de los Canales de Calcio/uso terapéutico , Dihidroergotamina/uso terapéutico , Interacciones Farmacológicas , Femenino , Cefalea/tratamiento farmacológico , Cefalea/etiología , Humanos , Hipertensión/complicaciones , Hipertensión/tratamiento farmacológico , Persona de Mediana Edad , Esclerosis Múltiple Recurrente-Remitente/complicaciones , Esclerosis Múltiple Recurrente-Remitente/fisiopatología , Guías de Práctica Clínica como Asunto , Vasoconstrictores/uso terapéutico , Vasodilatadores/efectos adversos , Vasodilatadores/uso terapéutico , Verapamilo/efectos adversos , Verapamilo/uso terapéuticoRESUMEN
PURPOSE: Thiosulfate has been shown to reduce the risk of cyanide toxicity during nitroprusside administration. Admixtures containing both agents may provide a safe and effective alternative to more expensive agents used to reduce blood pressure in the critically ill patient. This study determined the physical and chemical stability of a 1:10 nitroprusside:thiosulfate admixture, stored up to 48 hours. The economic consequences of a shift toward using thiosulfate and nitroprusside, and away from higher cost alternatives, are considered. METHODS: Seven samples of 50 mg nitroprusside and 500 mg thiosulfate were prepared and stored away from light, at room temperature, and in a refrigerator prepared in D5W and NS. Each sample was analyzed via a novel high-performance liquid chromatographic (HPLC) method at time 0, 8, 24, and 48 hours. The method was tested and passed specifications for linearity, reproducibility, and accuracy. A visual inspection by 9 licensed pharmacists was used to demonstrate physical stability. A cost evaluation comparing nitroprusside and thiosulfate to alternative agents was completed. RESULTS: The concentration of both nitroprusside and thiosulfate remain greater than 95% of the initial concentration through 48 hours. Physical compatibility was confirmed in all samples tested through 72 hours. CONCLUSION: The combination of nitroprusside and thiosulfate is chemically and physically stable as a single compounded dose for up to 48 hours when stored at room temperature and protected from light. The admixture represents an inexpensive option to other higher cost alternatives such as nicardipine or clevidipine.
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PURPOSE: Recommendations for the use of medications with continuous enteral nutrition are provided. METHODS: A literature review was conducted to identify primary literature reporting medication interactions with continuous enteral nutrition. For medications without supporting literature, manufacturers were contacted for information. Package inserts for specific medications were also investigated for any information to help guide recommendations. If no specific recommendations were made by the pharmaceutical manufacturer or the package insert concerning administration of products with continuous enteral nutrition, a tertiary database was consulted. Recommendations were generated by a consensus of clinicians for those medications that lacked specific recommendations in the primary literature or from the pharmaceutical manufacturer. Documentation of medication interactions with continuous enteral nutrition and food was then collated along with specific recommendations on how to administer the medication with regard to continuous enteral nutrition. Recommendations were classified as strong (grade 1) or weak (grade 2). The quality of evidence was classified as high (grade A), moderate (grade B), or low (grade C). RESULTS: Forty-six medications commonly given to hospitalized patients were evaluated. Twenty-four medications had recommendations based on available data, and the remaining 22 medications had recommendations based on a consensus of clinicians. CONCLUSION: There was a lack of published data regarding drug-nutrient interactions for a majority of the drugs commonly administered to patients receiving continuous enteral nutrition. Clinicians should recognize potential drug-nutrient interactions and use available evidence to optimize patients' drug therapy.