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1.
Nature ; 617(7959): 55-60, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37138107

RESUMEN

Planets with short orbital periods (roughly under 10 days) are common around stars like the Sun1,2. Stars expand as they evolve and thus we expect their close planetary companions to be engulfed, possibly powering luminous mass ejections from the host star3-5. However, this phase has never been directly observed. Here we report observations of ZTF SLRN-2020, a short-lived optical outburst in the Galactic disk accompanied by bright and long-lived infrared emission. The resulting light curve and spectra share striking similarities with those of red novae6,7-a class of eruptions now confirmed8 to arise from mergers of binary stars. Its exceptionally low optical luminosity (approximately 1035 erg s-1) and radiated energy (approximately 6.5 × 1041 erg) point to the engulfment of a planet of fewer than roughly ten Jupiter masses by its Sun-like host star. We estimate the Galactic rate of such subluminous red novae to be roughly between 0.1 and several per year. Future Galactic plane surveys should routinely identify these, showing the demographics of planetary engulfment and the ultimate fate of planets in the inner Solar System.

2.
Nature ; 610(7931): 269-272, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36224416

RESUMEN

The Wolf-Rayet (WR) binary system WR140 is a close (0.9-16.7 mas; ref. 1) binary star consisting of an O5 primary and WC7 companion2 and is known as the archetype of episodic dust-producing WRs. Dust in WR binaries is known to form in a confined stream originating from the collision of the two stellar winds, with orbital motion of the binary sculpting the large-scale dust structure into arcs as dust is swept radially outwards. It is understood that sensitive conditions required for dust production in WR140 are only met around periastron when the two stars are sufficiently close2-4. Here we present multiepoch imagery of the circumstellar dust shell of WR140. We constructed geometric models that closely trace the expansion of the intricately structured dust plume, showing that complex effects induced by orbital modulation may result in a 'Goldilocks zone' for dust production. We find that the expansion of the dust plume cannot be reproduced under the assumption of a simple uniform-speed outflow, finding instead the dust to be accelerating. This constitutes a direct kinematic record of dust motion under acceleration by radiation pressure and further highlights the complexity of the physical conditions in colliding-wind binaries.

3.
Lung ; 200(6): 737-745, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36216921

RESUMEN

PURPOSE: Tissue acquisition in lung cancer is vital for multiple reasons. Primary reasons reported for molecular testing failure in lung cancer biopsy specimens include insufficient amount of tumor cells provided and inadequate tissue quality. Robotic bronchoscopy is a new tool enabling peripheral pulmonary lesion sampling; however, diagnostic yield remains imperfect possibly due to the location of nodules adjacent to or outside of the airway. The 1.1-mm cryoprobe is a novel diagnostic tool and accesses tissue in a 360-degree manner, thus potentially sampling eccentric/adjacent lesions. This study examines the diagnostic yield of the cryoprobe compared to standard needle aspiration and forceps biopsy. It additionally evaluates yield for molecular markers in cases of lung cancer. METHODS: This is a retrospective analysis of 112 patients with 120 peripheral pulmonary lesions biopsied via robotic bronchoscopy using needle aspirate, forceps, and cryobiopsy. RESULTS: The overall diagnostic yield was 90%. Nearly 18% of diagnoses were made exclusively from the cryobiopsy sample. Molecular analysis was adequate on all cryobiopsy samples sent. Digital imaging software confirmed an increase in quantity and quality of samples taken via cryobiopsy compared to needle aspirate and traditional forceps biopsy. CONCLUSION: Using the 1.1-mm cryoprobe to biopsy PPN combined with the Ion robotic bronchoscopy system is safe, feasible, and provides more diagnostic tissue than needle aspirates or traditional forceps biopsies. The combination of cryobiopsy with robotic-assisted bronchoscopy increased diagnostic yield, likely due to its 360-degree tissue acquisition which is beneficial when targeting extraluminal lesions adjacent to the airway.


Asunto(s)
Criocirugía , Neoplasias Pulmonares , Procedimientos Quirúrgicos Robotizados , Humanos , Estudios Retrospectivos , Broncoscopía/métodos , Pulmón/patología , Biopsia/métodos , Neoplasias Pulmonares/patología
4.
Semin Respir Crit Care Med ; 41(5): 758-784, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32777856

RESUMEN

Sarcoidosis is a multisystemic granulomatous disorder that can affect virtually any organ. However, pulmonary and thoracic lymph node involvement predominates; abnormalities on chest radiographs are present in 80 to 90% of patients with sarcoidosis. High-resolution computed tomographic (HRCT) scans are superior to chest X-rays in assessing extent of disease, and some CT features may discriminate an active inflammatory component (which may be amenable to therapy) from fibrosis (for which therapy is not indicated). Typical findings on HRCT include micronodules, perilymphatic and bronchocentric distribution, perihilar opacities, and varying degrees of fibrosis. Less common findings on CT include mass-like or alveolar opacities, miliary opacities, mosaic attenuation, honeycomb cysts, and cavitation. With progressive disease, fibrosis, architectural distortion, upper lobe volume loss with hilar retraction, coarse linear bands, cysts, and bullae may be observed. We discuss the salient CT findings in patients with sarcoidosis (with a major focus on pulmonary features) and present classical radiographic and histopathological images of a few extrapulmonary sites.


Asunto(s)
Sarcoidosis Pulmonar/diagnóstico por imagen , Sarcoidosis Pulmonar/patología , Tomografía Computarizada por Rayos X , Progresión de la Enfermedad , Fibrosis , Granuloma/diagnóstico por imagen , Granuloma/patología , Humanos , Pulmón/diagnóstico por imagen , Pulmón/patología , Linfadenopatía/diagnóstico por imagen , Linfadenopatía/patología , Radiografía Torácica , Sarcoidosis/diagnóstico por imagen , Sarcoidosis/patología
5.
J Pediatr ; 213: 30-37.e3, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31256913

RESUMEN

OBJECTIVES: To determine parent preferences for discharge with home oxygen in infants with bronchopulmonary dysplasia. STUDY DESIGN: This was a prospective study of parents of infants born at <32 weeks' gestation with established bronchopulmonary dysplasia and approaching neonatal intensive care unit (NICU) discharge. Parents were presented a hypothetical scenario of an infant who failed weaning to room air and 2 options: discharge with home oxygen or try longer to wean oxygen. The initial scenario risks reflected a 1.5-week difference in NICU length of stay and no differences in other outcomes. Length of stay and readmission outcomes were increased or decreased until the parent switched preference. Three months after discharge, parents were asked to reconsider their preference. Differences were analyzed by χ2 or Kruskal-Wallis tests. RESULTS: Of 125 parents, 50% preferred home oxygen. For parents preferring home oxygen, the most important reason was comfort at home (79%). Forty percent switched preference when the length of stay difference decreased by 1 week; 35% switched when readmission increased by 5%. For parents preferring to stay in NICU, the most important reason was fear of taking care of the child at home (73%). Thirty-two percent switched preference when the length of stay difference increased by 1 week; 31% switched when readmission decreased by 5%. One hundred ten parents completed the 3-month follow-up; 80 were discharged with home oxygen. Seventy-eight percent would prefer home oxygen (97% who initially preferred home oxygen and 60% who initially preferred to stay in the NICU). CONCLUSIONS: Parents weigh differences in NICU length of stay and readmission risk similarly. After discharge, most prefer earlier discharge with home oxygen. Earlier education to increase comfort with home technology may facilitate NICU discharge planning.


Asunto(s)
Displasia Broncopulmonar/terapia , Servicios de Atención de Salud a Domicilio , Terapia por Inhalación de Oxígeno , Padres/psicología , Prioridad del Paciente , Femenino , Humanos , Lactante , Recién Nacido , Recien Nacido Prematuro , Tiempo de Internación , Masculino , Alta del Paciente , Estudios Prospectivos
6.
Curr Cardiol Rep ; 21(7): 63, 2019 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-31147795

RESUMEN

PURPOSE OF REVIEW: This review discusses the normal anatomy and pathology of the tricuspid valve (TV) and right side of the heart. Emphasis is on those anatomic and pathologic features relevant to interventions intended to restore normal function to the TV in disease states. RECENT FINDINGS: TV pathology is less common than aortic and mitral valve pathology, and treatment and outcomes for interventions face considerable hurdles. New innovations and early data showing safety and efficacy in transcatheter interventions have transformed TV interventions into the next frontier in cardiac valve disease treatment. Certain features of the TV and right heart have presented themselves as potential targets, as well as impediments, for TV intervention. The causes of TV pathology and the anatomy of the TV and right heart bring unique challenges to intervention. Approaches to intervention will continue to progress and change the way we view and treat TV pathology.


Asunto(s)
Enfermedades de las Válvulas Cardíacas/patología , Insuficiencia de la Válvula Tricúspide/patología , Válvula Tricúspide/anatomía & histología , Válvula Tricúspide/patología , Implantación de Prótesis de Válvulas Cardíacas , Humanos , Resultado del Tratamiento , Válvula Tricúspide/cirugía , Insuficiencia de la Válvula Tricúspide/cirugía
7.
BMC Pediatr ; 18(1): 199, 2018 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-29933740

RESUMEN

BACKGROUND: Measuring adolescents' preferences for health states can play an important role in evaluating the delivery of pediatric healthcare. However, formal evaluation of the common direct preference elicitation methods for health states has not been done with adolescents. Therefore, the purpose of this study is to test how these methods perform in terms of their feasibility, reliability, and validity for measuring health state preferences in adolescents. METHODS: This study used a web-based survey of adolescents, 18 years of age or younger, living in the United States. The survey included four health states, each comprised of six attributes. Preferences for these health states were elicited using the visual analogue scale, time trade-off, and standard gamble. The feasibility, test-retest reliability, and construct validity of each of these preference elicitation methods were tested and compared. RESULTS: A total of 144 participants were included in this study. Using a web-based survey format to elicit preferences for health states from adolescents was feasible. A majority of participants completed all three elicitation methods, ranked those methods as being easy, with very few requiring assistance from someone else. However, all three elicitation methods demonstrated weak test-retest reliability, with Kendall's tau-a values ranging from 0.204 to 0.402. Similarly, all three methods demonstrated poor construct validity, with 9-50% of all rankings aligning with our expectations. There were no significant differences across age groups. CONCLUSIONS: Using a web-based survey format to elicit preferences for health states from adolescents is feasible. However, the reliability and construct validity of the methods used to elicit these preferences when using this survey format are poor. Further research into the effects of a web-based survey approach to eliciting preferences for health states from adolescents is needed before health services researchers or pediatric clinicians widely employ these methods.


Asunto(s)
Salud del Adolescente , Estado de Salud , Encuestas y Cuestionarios , Adolescente , Niño , Estudios de Factibilidad , Humanos , Internet , Prioridad del Paciente , Reproducibilidad de los Resultados
8.
Blood ; 122(24): 3918-28, 2013 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-24128862

RESUMEN

Granulocyte colony-stimulating factor (Gcsf) drives the proliferation and differentiation of granulocytes, monocytes, and macrophages (mφs) from hematopoietic stem and progenitor cells (HSPCs). Analysis of the zebrafish genome indicates the presence of 2 Gcsf ligands, likely resulting from a duplication event in teleost evolution. Although Gcsfa and Gcsfb share low sequence conservation, they share significant similarity in their predicted ligand/receptor interaction sites and structure. Each ligand displays differential temporal expression patterns during embryogenesis and spatial expression patterns in adult animals. To determine the functions of each ligand, we performed loss- and gain-of-function experiments. Both ligands signal through the Gcsf receptor to expand primitive neutrophils and mφs, as well as definitive granulocytes. To further address their functions, we generated recombinant versions and tested them in clonal progenitor assays. These sensitive in vitro techniques indicated similar functional attributes in supporting HSPC growth and differentiation. Finally, in addition to supporting myeloid differentiation, zebrafish Gcsf is required for the specification and proliferation of hematopoietic stem cells, suggesting that Gcsf represents an ancestral cytokine responsible for the broad support of HSPCs. These findings may inform how hematopoietic cytokines evolved following the diversification of teleosts and mammals from a common ancestor.


Asunto(s)
Factor Estimulante de Colonias de Granulocitos/genética , Hematopoyesis/genética , Proteínas de Pez Cebra/genética , Pez Cebra/genética , Animales , Animales Modificados Genéticamente , Embrión no Mamífero/embriología , Embrión no Mamífero/metabolismo , Femenino , Regulación del Desarrollo de la Expresión Génica , Técnicas de Silenciamiento del Gen , Factor Estimulante de Colonias de Granulocitos/metabolismo , Sistema Hematopoyético/embriología , Sistema Hematopoyético/metabolismo , Hibridación in Situ , Ligandos , Proteínas Luminiscentes/genética , Proteínas Luminiscentes/metabolismo , Masculino , Microscopía Confocal , Mielopoyesis/genética , Receptores de Factor Estimulante de Colonias de Granulocito/genética , Receptores de Factor Estimulante de Colonias de Granulocito/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal/genética , Pez Cebra/embriología , Proteínas de Pez Cebra/metabolismo
9.
Opt Lett ; 40(12): 2778-81, 2015 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-26076260

RESUMEN

We investigate theoretically the parametric frequency comb generation in silicon microresonators at telecom and mid-infrared (MIR) wavelengths in the presence of multiphoton absorption and free-carrier effects using a modified Lugiato-Lefever model. We show that parametric oscillation may occur at MIR wavelengths, provided that the free-carrier lifetime is sufficiently short or the optical pump power is sufficiently low, but is inhibited at telecom wavelengths. In addition, we propose an etchless, air-clad silicon microresonator that enables an octave-spanning frequency comb in a completely passive device.

10.
Opt Lett ; 40(17): 4138-41, 2015 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-26368731

RESUMEN

We demonstrate strong nonlinearities of n2=8.6±1.1×10(-15) cm2 W(-1) in single-crystal silicon carbide (SiC) at a wavelength of 2360 nm. We use a high-confinement SiC waveguide fabricated based on a high-temperature smart-cut process.

11.
Opt Lett ; 39(15): 4518-21, 2014 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-25078217

RESUMEN

We report, to the best of our knowledge, the first demonstration of octave-spanning supercontinuum generation (SCG) on a silicon chip, spanning from the telecommunications c-band near 1.5 µm to the mid-infrared region beyond 3.6 µm. The SCG presented here is characterized by soliton fission and dispersive radiation across two zero group-velocity dispersion wavelengths. In addition, we numerically investigate the role of multiphoton absorption and free carriers, confirming that these nonlinear loss mechanisms are not detrimental to SCG in this regime.

12.
Blood ; 118(5): 1274-82, 2011 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-21415264

RESUMEN

Identification of hematopoietic progenitor cells in the zebrafish (Danio rerio) has been hindered by a lack of functional assays to gauge proliferative potential and differentiation capacity. To investigate the nature of myeloerythroid progenitor cells, we developed clonal methylcellulose assays by using recombinant zebrafish erythropoietin and granulocyte colony-stimulating factor. From adult whole kidney marrow, erythropoietin was required to support erythroid colony formation, and granulocyte colony-stimulating factor was required to support the formation of colonies containing neutrophils, monocytes, and macrophages. Myeloid and erythroid colonies showed distinct morphologies and were easily visualized and scored by their expression of lineage-specific fluorescent transgenes. Analysis of the gene-expression profiles after isolation of colonies marked by gata1:DsRed or mpx:eGFP transgenes confirmed our morphological erythroid and myeloid lineage designations, respectively. The majority of progenitor activity was contained within the precursor light scatter fraction, and more immature precursors were present within the lymphoid fraction. Finally, we performed kinetic analyses of progenitor activity after sublethal irradiation and demonstrated that recovery to preirradiation levels occurred by 14 days after irradiation. Together, these experiments provide the first report of clonal hematopoietic progenitor assays in the zebrafish and establish the number, characteristics, and kinetics of myeloerythroid progenitors during both steady-state and stress hematopoiesis.


Asunto(s)
Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/fisiología , Pez Cebra/embriología , Animales , Animales Modificados Genéticamente , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Células Clonales , Embrión no Mamífero , Células Eritroides/efectos de los fármacos , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Hematopoyesis/efectos de los fármacos , Hematopoyesis/genética , Hematopoyesis/fisiología , Células Madre Hematopoyéticas/efectos de los fármacos , Péptidos y Proteínas de Señalización Intercelular/farmacología , Células Mieloides/efectos de los fármacos , Células Mieloides/fisiología , Proteínas Recombinantes/farmacología , Pez Cebra/genética , Pez Cebra/fisiología
13.
Ann Otol Rhinol Laryngol ; 132(11): 1487-1492, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36951110

RESUMEN

OBJECTIVES: To present a patient with the first case of NTM (nontuberculous mycobacteria) infection of the larynx extending to cervical trachea, and the first case of subglottic stenosis associated with an NTM infection. METHODS: Case report and review of the literature. RESULTS: A 68-year-old female with history of prior smoking, gastroesophageal reflux disease, asthma, bronchiectasis, and tracheobronchomalacia presented with a 3-month history of shortness of breath, exertional inspiratory stridor, and hoarseness. Flexible laryngoscopy demonstrated ulceration of medial aspect of right vocal fold and subglottic tissue abnormality with crusting and ulceration extending through the upper trachea. Microdirect laryngoscopy with tissue biopsies and carbon dioxide (CO2) laser ablation of disease completed, and intraoperative culture revealed positive Aspergillus and acid-fast bacilli with Mycobacterium abscessus (type of NTM). Patient began antimicrobial treatment of cefoxitin, imipenem, amikacin, azithromycin, clofazimine, and itraconazole. Fourteen months after initial presentation, patient developed subglottic stenosis with limited extension into the proximal trachea prompting CO2 laser incision, balloon dilation, and steroid injection of the subglottic stenosis. Patient remains disease free without further subglottic stenosis. CONCLUSION: Laryngeal NTM infections are exceedingly rare. Failure to consider NTM infection in the differential diagnosis when presented with an ulcerative, exophytic mass in patients with increased risk factors (structural lung disease, Pseudomonas colonization, chronic steroid use, prior NTM positivity) may result in insufficient tissue evaluation, delayed diagnosis, and disease progression.


Asunto(s)
Laringe , Infecciones por Mycobacterium no Tuberculosas , Femenino , Humanos , Anciano , Tráquea , Constricción Patológica , Infecciones por Mycobacterium no Tuberculosas/diagnóstico , Infecciones por Mycobacterium no Tuberculosas/terapia , Infecciones por Mycobacterium no Tuberculosas/microbiología , Micobacterias no Tuberculosas , Esteroides
14.
Am J Case Rep ; 24: e937955, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36855283

RESUMEN

BACKGROUND Cardiac allograft vasculopathy (CAV) is a post-orthotopic heart transplant (OHT) complication driven by intimal smooth muscle proliferation and immune hyperactivity to donor heart tissue. Accelerated CAV leads to allograft failure within 1 year after receiving a normal angiogram result. Viruses can contribute to CAV development, but CAV after SARS-CoV-2 infection has not been reported to date. CASE REPORT A 48-year-old man, 5 years after OHT for non-ischemic cardiomyopathy, was admitted to the Cardiac Care Unit with 3 days of abdominal pain, dyspnea, and palpitations. His medical history included hyperlipidemia and insulin-dependent diabetes. He was compliant with all medications. Two months prior, he had a mild COVID-19 case. An echocardiogram and coronary angiogram 6 and 9 months prior, respectively, were unremarkable. Right and left heart catheterization demonstrated increased filling pressures, a cardiac index of 1.7 L/ml/m², and diffuse vasculopathy most severe in the LAD artery. Flow could not be restored despite repeated ballooning and intra-catheter adenosine. Empiric ionotropic support, daily high-dose methylprednisolone, and plasmapheresis were started. A few days later, the patient had cardiac arrest requiring venoarterial extracorporeal membranous oxygenation. Given CAV's irreversibility, re-transplantation was considered, but the patient had an episode of large-volume hemoptysis and remained clinically unstable for transplant. The patient died while on palliative care. CONCLUSIONS Our patient developed accelerated CAV 2 months after having COVID-19. While CAV has known associations with certain viruses, its incidence after SARS-CoV-2 infection is unknown. Further research is needed to determine if prior SARS-CoV-2 infection is a risk factor for development of CAV in OHT recipients.


Asunto(s)
COVID-19 , Trasplante de Corazón , Masculino , Humanos , Persona de Mediana Edad , Trasplante de Corazón/efectos adversos , SARS-CoV-2 , Donantes de Tejidos , Angiografía Coronaria , Aloinjertos
15.
Cells ; 12(11)2023 05 23.
Artículo en Inglés | MEDLINE | ID: mdl-37296576

RESUMEN

As an essential component of the sarcomere, actin thin filament stems from the Z-disk extend toward the middle of the sarcomere and overlaps with myosin thick filaments. Elongation of the cardiac thin filament is essential for normal sarcomere maturation and heart function. This process is regulated by the actin-binding proteins Leiomodins (LMODs), among which LMOD2 has recently been identified as a key regulator of thin filament elongation to reach a mature length. Few reports have implicated homozygous loss of function variants of LMOD2 in neonatal dilated cardiomyopathy (DCM) associated with thin filament shortening. We present the fifth case of DCM due to biallelic variants in the LMOD2 gene and the second case with the c.1193G>A (p.W398*) nonsense variant identified by whole-exome sequencing. The proband is a 4-month male infant of Hispanic descent with advanced heart failure. Consistent with previous reports, a myocardial biopsy exhibited remarkably short thin filaments. However, compared to other cases of identical or similar biallelic variants, the patient presented here has an unusually late onset of cardiomyopathy during infancy. Herein, we present the phenotypic and histological features of this variant, confirm the pathogenic impact on protein expression and sarcomere structure, and discuss the current knowledge of LMOD2-related cardiomyopathy.


Asunto(s)
Cardiomiopatías , Cardiomiopatía Dilatada , Recién Nacido , Lactante , Masculino , Humanos , Cardiomiopatía Dilatada/genética , Secuenciación del Exoma , Homocigoto , Corazón
16.
Opt Express ; 20(6): 6488-95, 2012 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-22418531

RESUMEN

We report extremely large probe-idler separation wavelength conversion (545 nm) and unicast (700 nm) of 10-Gb/s data signals using a dispersion-engineered silicon nanowaveguide. Dispersion-engineered phase matching in the device provides a continuous four-wave-mixing efficiency 3-dB bandwidth exceeding 800 nm. We report the first data validation of wavelength conversion (data modulated probe) and unicast (data modulated pump) of 10-Gb/s data with probe-idler separations spanning 60 nm up to 700 nm accompanied with sensitivity gain in a single device. These demonstrations further validate the silicon platform as a highly broadband flexible platform for nonlinear all-optical data manipulation.


Asunto(s)
Nanopartículas/química , Nanotecnología/instrumentación , Refractometría/instrumentación , Procesamiento de Señales Asistido por Computador/instrumentación , Silicio/química , Resonancia por Plasmón de Superficie/instrumentación , Telecomunicaciones/instrumentación , Diseño Asistido por Computadora , Diseño de Equipo , Análisis de Falla de Equipo , Nanopartículas/ultraestructura
17.
Opt Express ; 20(24): 26935-41, 2012 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-23187548

RESUMEN

We report the first experimental demonstration of broadband frequency comb generation from a single-frequency pump laser at 1-µm using parametric oscillation in a high-Q silicon-nitride ring resonator. The resonator dispersion is engineered to have a broad anomalous group velocity dispersion region near the pump wavelength for efficient parametric four-wave mixing. The comb spans 55 THz with a 230-GHz free spectral range. These results demonstrate the powerful advantage of dispersion engineering in chip-based devices for producing combs with a wide range of pump wavelengths.


Asunto(s)
Filtración/instrumentación , Rayos Láser , Luz , Dispositivos Ópticos , Refractometría/instrumentación , Transductores , Simulación por Computador , Diseño Asistido por Computadora , Diseño de Equipo
18.
Respir Med Case Rep ; 35: 101566, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34976718

RESUMEN

Pulmonary alveolar proteinosis (PAP) is a rare pulmonary syndrome that is characterized by the accumulation of excess surfactant in the alveolar space, leading to impaired gas exchange. Sirolimus-induced PAP is an extremely rare entity that has only been described in the literature in a small number of case reports. We present a case of a 39-year-old female with acute lymphocytic leukemia who underwent stem cell transplant, complicated by graft-versus-host-disease (GVHD) involving the skin for which she was treated with steroids, photopheresis, sirolimus, and ruxolitinib. She was admitted to the intensive care unit (ICU) for acute on chronic hypoxic respiratory failure requiring intermittent mechanical ventilation. Computed tomography (CT) of the chest showed thickened inter- and intralobular septa with ground glass opacities and consolidation with a limited geographic pattern. Bronchoalveolar lavage fluid was stained with Periodic acid-Schiff (PAS), which was positive for extracellular proteinaceous material. Autoimmune studies including antibody levels for primary autoimmune pulmonary alveolar proteinosis (PAP) were negative. The patient was diagnosed with sirolimus-induced secondary PAP, and sirolimus was discontinued. A year later, she no longer required supplemental oxygen, and repeat CT imaging showed only faint residual disease. This is the only documented case of sirolimus-induced PAP in a stem cell transplant recipient and the first case reported in which the patient developed severe hypoxic respiratory failure requiring mechanical ventilation. In the right clinical context, PAP can be diagnosed with characteristic high resolution computed tomography (HRCT) findings, serum GM-CSF antibody levels, and bronchoscopy with bronchoalveolar lavage.

19.
Lancet Infect Dis ; 22(12): e370-e376, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36057267

RESUMEN

On Jan 22, 2020, a day after the USA reported its first COVID-19 case, the Johns Hopkins University Center for Systems Science and Engineering (JHU CSSE) launched the first global real-time coronavirus surveillance system: the JHU CSSE COVID-19 Dashboard. As of June 1, 2022, the dashboard has served the global audience for more than 30 consecutive months, totalling over 226 billion feature layer requests and 3·6 billion page views. The highest daily record was set on March 29, 2020, with more than 4·6 billion requests and over 69 million views. This Personal View reveals the fundamental technical details of the entire data system underlying the dashboard, including data collection, data fusion logic, data curation and sharing, anomaly detection, data corrections, and the human resources required to support such an effort. The Personal View also covers the challenges, ranging from data visualisation to reporting standardisation. The details presented here help develop a framework for future, large-scale public health-related data collection and reporting.


Asunto(s)
COVID-19 , Humanos , Universidades , Recolección de Datos , Salud Pública
20.
Opt Express ; 19(13): 12172-9, 2011 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-21716454

RESUMEN

We experimentally demonstrate four-wave-mixing (FWM)-based continuous wavelength conversion of optical differential-phase-shift-keyed (DPSK) signals with large wavelength conversion ranges as well as simultaneous wavelength conversion of dual-wavelength channels with mixed modulation formats in 1.1-cm-long dispersion-engineered silicon waveguides. We first validate up to 100-nm wavelength conversion range for 10-Gb/s DPSK signals, showcasing the capability to perform phase-preserving operations at high bit rates in chip-scale devices over wide conversion ranges. We further validate the wavelength conversion of dual-wavelength channels modulated with 10-Gb/s packetized phase-shift-keyed (PSK) and amplitude-shift-keyed (ASK) signals; demonstrate simultaneous operation on multiple channels with mixed formats in chip-scale devices. For both configurations, we measure the spectral and temporal responses and evaluate the performances using bit-error-rate (BER) measurements.


Asunto(s)
Dispositivos Ópticos , Óptica y Fotónica/instrumentación , Procesamiento de Señales Asistido por Computador/instrumentación , Silicio/química , Telecomunicaciones/instrumentación , Diseño de Equipo , Dinámicas no Lineales , Óptica y Fotónica/métodos
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