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1.
Nature ; 581(7809): 391-395, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32461651

RESUMEN

More than three-quarters of the baryonic content of the Universe resides in a highly diffuse state that is difficult to detect, with only a small fraction directly observed in galaxies and galaxy clusters1,2. Censuses of the nearby Universe have used absorption line spectroscopy3,4 to observe the 'invisible' baryons, but these measurements rely on large and uncertain corrections and are insensitive to most of the Universe's volume and probably most of its mass. In particular, quasar spectroscopy is sensitive either to the very small amounts of hydrogen that exist in the atomic state, or to highly ionized and enriched gas4-6 in denser regions near galaxies7. Other techniques to observe these invisible baryons also have limitations; Sunyaev-Zel'dovich analyses8,9 can provide evidence from gas within filamentary structures, and studies of X-ray emission are most sensitive to gas near galaxy clusters9,10. Here we report a measurement of the baryon content of the Universe using the dispersion of a sample of localized fast radio bursts; this technique determines the electron column density along each line of sight and accounts for every ionized baryon11-13. We augment the sample of reported arcsecond-localized14-18 fast radio bursts with four new localizations in host galaxies that have measured redshifts of 0.291, 0.118, 0.378 and 0.522. This completes a sample sufficiently large to account for dispersion variations along the lines of sight and in the host-galaxy environments11, and we derive a cosmic baryon density of [Formula: see text] (95 per cent confidence; h70 = H0/(70 km s-1 Mpc-1) and H0 is Hubble's constant). This independent measurement is consistent with values derived from the cosmic microwave background and from Big Bang nucleosynthesis19,20.

2.
Opt Express ; 32(5): 8284-8307, 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38439488

RESUMEN

Numerical modeling of ultrashort pulse propagation is important for designing and understanding the underlying dynamical processes in devices that take advantage of highly nonlinear interactions in dispersion-engineered optical waveguides. Once the spectral bandwidth reaches an octave or more, multiple types of nonlinear polarization terms can drive individual optical frequencies. This issue is particularly prominent in χ(2) devices where all harmonics of the input pulse are generated and there can be extensive spectral overlap between them. Single-envelope approaches to pulse propagation have been developed to address these complexities; this has led to a significant mismatch between the strategies used to analyze moderate-bandwidth devices (usually involving multi-envelope models) and those used to analyze octave-spanning devices (usually involving models with one envelope per waveguide mode). Here we unify the different strategies by developing a common framework, applicable to any optical bandwidth, that allows for a side-by-side comparison between single- and multi-envelope models. We include both χ(2) and χ(3) interactions in these models, with emphasis on χ(2) interactions. We show a detailed example based on recent supercontinuum generation experiments in a thin-film LiNbO3 on sapphire quasi-phase-matching waveguide. Our simulations of this device show good agreement between single- and multi-envelope models in terms of the frequency comb properties of the electric field, even for multi-octave-spanning spectra. Building on this finding, we explore how the multi-envelope approach can be used to develop reduced models that help build physical insights about new ultrafast photonics devices enabled by modern dispersion-engineered waveguides, and discuss practical considerations for the choice of such models. More broadly, we give guidelines on the pros and cons of the different modeling strategies in the context of device design, numerical efficiency, and accuracy of the simulations.

3.
Am J Emerg Med ; 75: 33-36, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37897918

RESUMEN

RATIONALE AND OBJECTIVE: To determine if patient demographic data, medical history, physical examination, and laboratory tests will help predict likelihood of imaging-based diagnosis using CT of the neck performed in the ED for a chief complaint of throat pain. MATERIAL AND METHODS: Single institutional, retrospective review of 367 CT scans of the neck performed for the evaluation of throat pain in the ED from August 2013 to September 2019. Patients' clinical history, physical exams, lab findings, and imaging results were recorded. RESULTS: A total of 367 CT scans of the neck performed for the evaluation of throat pain included a recorded exam and clinical history. Of these cases, we noted that the presence of cervical lymphadenopathy (OR = 2.69; 95% CI, 1.37-5.49), tonsillar findings (OR = 2.94; 95% CI, 1.4-6.57), increased white blood cell count (OR = 1.08; 95% CI, 1.02-1.15), and temperature (OR = 1.94; 95% CI, 1.1-3.6) were associated with increased likelihood of obtaining a diagnostic CT scan. CONCLUSION: Consideration of tonsillar abnormalities, lymphadenopathy, body temperature, and measured leukocyte count prior to ordering CT scans of the neck for throat pain may increase the diagnostic yield of such exams and decrease CT utilization in the ED.


Asunto(s)
Linfadenopatía , Faringitis , Humanos , Faringe , Faringitis/diagnóstico por imagen , Dolor , Tomografía Computarizada por Rayos X , Linfadenopatía/diagnóstico por imagen , Estudios Retrospectivos
4.
Clin Infect Dis ; 76(8): 1358-1363, 2023 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-36504336

RESUMEN

BACKGROUND: In the United States, influenza activity during the 2021-2022 season was modest and sufficient enough to estimate influenza vaccine effectiveness (VE) for the first time since the beginning of the coronavirus disease 2019 pandemic. We estimated influenza VE against laboratory-confirmed outpatient acute illness caused by predominant A(H3N2) viruses. METHODS: Between October 2021 and April 2022, research staff across 7 sites enrolled patients aged ≥6 months seeking outpatient care for acute respiratory illness with cough. Using a test-negative design, we assessed VE against influenza A(H3N2). Due to strong correlation between influenza and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination, participants who tested positive for SARS-CoV-2 were excluded from VE estimations. Estimates were adjusted for site, age, month of illness, race/ethnicity, and general health status. RESULTS: Among 6260 participants, 468 (7%) tested positive for influenza only, including 440 (94%) for A(H3N2). All 206 sequenced A(H3N2) viruses were characterized as belonging to genetic group 3C.2a1b subclade 2a.2, which has antigenic differences from the 2021-2022 season A(H3N2) vaccine component that belongs to clade 3C.2a1b subclade 2a.1. After excluding 1948 SARS-CoV-2-positive patients, 4312 patients were included in analyses of influenza VE; 2463 (57%) were vaccinated against influenza. Effectiveness against A(H3N2) for all ages was 36% (95% confidence interval, 20%-49%) overall. CONCLUSIONS: Influenza vaccination in 2021-2022 provided protection against influenza A(H3N2)-related outpatient visits among young persons.


Asunto(s)
COVID-19 , Vacunas contra la Influenza , Gripe Humana , Humanos , Estados Unidos/epidemiología , Gripe Humana/epidemiología , Gripe Humana/prevención & control , Subtipo H3N2 del Virus de la Influenza A , Estaciones del Año , Eficacia de las Vacunas , COVID-19/epidemiología , COVID-19/prevención & control , SARS-CoV-2 , Vacunación , Virus de la Influenza B
5.
Emerg Infect Dis ; 29(12): 2442-2450, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37917142

RESUMEN

Both SARS-CoV-2 and influenza virus can be transmitted by asymptomatic, presymptomatic, or symptomatic infected persons. We assessed effects on work attendance while ill before and during the COVID-19 pandemic in the United States by analyzing data collected prospectively from persons with acute respiratory illnesses enrolled in a multistate study during 2018-2022. Persons with previous hybrid work experience were significantly less likely to work onsite on the day before through the first 3 days of illness than those without that experience, an effect more pronounced during the COVID-19 pandemic than during prepandemic influenza seasons. Persons with influenza or COVID-19 were significantly less likely to work onsite than persons with other acute respiratory illnesses. Among persons with positive COVID-19 test results available by the second or third day of illness, few worked onsite. Hybrid and remote work policies might reduce workplace exposures and help reduce spread of respiratory viruses.


Asunto(s)
COVID-19 , Gripe Humana , Estados Unidos/epidemiología , Humanos , COVID-19/epidemiología , SARS-CoV-2 , Gripe Humana/epidemiología , Pandemias , Prueba de COVID-19
6.
Opt Express ; 31(5): 7103-7119, 2023 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-36859848

RESUMEN

We present a new type of dual optical frequency comb source capable of scaling applications to high measurement speeds while combining high average power, ultra-low noise operation, and a compact setup. Our approach is based on a diode-pumped solid-state laser cavity which includes an intracavity biprism operated at Brewster angle to generate two spatially-separated modes with highly correlated properties. The 15-cm-long cavity uses an Yb:CALGO crystal and a semiconductor saturable absorber mirror as an end mirror to generate more than 3 W average power per comb, below 80 fs pulse duration, a repetition rate of 1.03 GHz, and a continuously tunable repetition rate difference up to 27 kHz. We carefully investigate the coherence properties of the dual-comb by a series of heterodyne measurements, revealing several important features: (1) ultra-low jitter on the uncorrelated part of the timing noise; (2) the radio frequency comb lines of the interferograms are fully resolved in free-running operation; (3) we validate that through a simple measurement of the interferograms we can determine the fluctuations of the phase of all the radio frequency comb lines; (4) this phase information is used in a post-processing routine to perform coherently averaged dual-comb spectroscopy of acetylene (C2H2) over long timescales. Our results represent a powerful and general approach to dual-comb applications by combining low noise and high power operation directly from a highly compact laser oscillator.

7.
Opt Express ; 31(10): 15888, 2023 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-37157679

RESUMEN

This erratum corrects a typographical error in equation (8) of our published paper [Opt. Express31, 7103 (2023)10.1364/OE.479356]. All the calculations used the correct equation, so all the results and conclusions remain unchanged.

8.
Pituitary ; 26(1): 105-114, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36462067

RESUMEN

PURPOSE: Hypothalamic obesity (HO) is a complication associated with craniopharyngioma (CP). Attempts have been made to perioperatively predict the development of this complication, which can be severe and difficult to treat. METHODS: Patients who underwent first transsphenoidal surgical resection in a single center between February 2005 and March 2019 were screened; those who have had prior surgery or radiation, were aged below 18 years, or did not have follow up body mass index (BMI) after surgery were excluded. Primary end point was BMI within 2 years post-surgery. Hypothalamic involvement (HI) was graded based on preoperative and postoperative imaging with regards to anterior, posterior, left and right involvement. Data on baseline demographics, pre-operative and post-operative MRI, and endocrine function were collected. RESULTS: 45 patients met the inclusion and exclusion criteria. Most patients in our cohort underwent gross total resection (n = 35 patients). 13 patients were from no HI or anterior HI only group and 22 patients were classified as both anterior (ant) and posterior (post) HI group. There was no significant difference between the two groups in the gross total, subtotal or near total resection. Pre-operative BMI and post-operative BMI were significantly higher in patients who had ant and post HI on pre-operative MRI (p < 0.05 and p < 0.01, respectively). Similarly, post-operative BMI at 13-24 months was also significantly higher in the ant and post HI group on post-op MRI (p < 0.01). There was no significant difference between the two groups in terms of baseline adrenal insufficiency, thyroid insufficiency, gonadal insufficiency, IGF-1 levels, hyperprolactinemia, and diabetes insipidus. Diabetes insipidus was more common following surgery among those who had anterior and posterior involvement on pre-operative MRI (p < 0.05). CONCLUSIONS: HO appears to be predetermined by tumor involvement in the posterior hypothalamus observed on pre-operative MRI. Posterior HI on pre-operative MRI was also associated with the development of diabetes insipidus after surgery.


Asunto(s)
Craneofaringioma , Diabetes Insípida , Enfermedades Hipotalámicas , Neoplasias Hipofisarias , Humanos , Anciano , Craneofaringioma/diagnóstico por imagen , Craneofaringioma/cirugía , Estudios Retrospectivos , Neoplasias Hipofisarias/diagnóstico por imagen , Neoplasias Hipofisarias/cirugía , Neoplasias Hipofisarias/complicaciones , Enfermedades Hipotalámicas/diagnóstico por imagen , Enfermedades Hipotalámicas/cirugía , Hipotálamo Posterior/patología , Diabetes Insípida/etiología , Imagen por Resonancia Magnética , Complicaciones Posoperatorias , Obesidad , Resultado del Tratamiento
9.
Climacteric ; 26(4): 336-352, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37395104

RESUMEN

Vulvovaginal atrophy (VVA) is a chronic progressive condition that involves the genital and lower urinary tracts, related to the decrease of serum estrogenic levels when menopause occurs. The definition of genitourinary syndrome of menopause (GSM) is a medically more accurate, all-encompassing and publicly acceptable term than VVA. Due to the chronic progressive trend of GSM, symptoms tend to reappear after the cessation of therapy, and frequently long-term treatment is required. First-line therapies include vulvar and vaginal lubricant or moisturizers, and, in the case of failure, low-dose vaginal estrogens are the preferred pharmacological therapy. Populations of patients, such as breast cancer (BC) survivors, are affected by iatrogenic GSM symptoms with concerns about the use of hormonal therapies. The non-ablative erbium:YAG laser and the fractional microablative CO2 vaginal laser are the two main lasers evaluated for GSM treatment. The aim of this comprehensive review is to report the efficacy and safety of Er:YAG and CO2 vaginal lasers for GSM treatment. Vaginal laser therapy has been demonstrated to be effective in restoring vaginal health, improving VVA symptoms and sexual function. The data suggest that both Er:YAG and CO2 vaginal lasers are safe energy-based therapeutic options for management of VVA and/or GSM symptoms in postmenopausal women and BC survivors.


Asunto(s)
Neoplasias de la Mama , Terapia por Láser , Láseres de Gas , Láseres de Estado Sólido , Enfermedades Vaginales , Femenino , Humanos , Enfermedades Vaginales/cirugía , Enfermedades Vaginales/patología , Dióxido de Carbono , Menopausia , Vagina/cirugía , Vagina/patología , Neoplasias de la Mama/patología , Láseres de Estado Sólido/uso terapéutico , Atrofia
10.
Opt Express ; 30(4): 5075-5094, 2022 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-35209478

RESUMEN

Pulse trains emitted from dual-comb systems are designed to have low relative timing jitter, making them useful for many optical measurement techniques such as optical ranging and spectroscopy. However, the characterization of low-jitter dual-comb systems is challenging because it requires measurement techniques with high sensitivity. Motivated by this challenge, we developed a technique based on an optical heterodyne detection approach for measuring the relative timing jitter of two pulse trains. The method is suitable for dual-comb systems with essentially any repetition rate difference. Furthermore, the proposed approach allows for continuous and precise tracking of the sampling rate. To demonstrate the technique, we perform a detailed characterization of a single-mode-diode pumped Yb:CaF2 dual-comb laser from a free-running polarization-multiplexed cavity. This new laser produces 115-fs pulses at 160 MHz repetition rate, with 130 mW of average power in each comb. The detection noise floor for the relative timing jitter between the two pulse trains reaches 8.0 × 10-7 fs2/Hz (∼ 896 zs/Hz), and the relative root mean square (rms) timing jitter is 13 fs when integrating from 100 Hz to 1 MHz. This performance indicates that the demonstrated laser is highly compatible with practical dual-comb spectroscopy, ranging, and sampling applications. Furthermore, our results show that the relative timing noise measurement technique can characterize dual-comb systems operating in free-running mode or with finite repetition rate differences while providing a sub-attosecond resolution, which was not feasible with any other approach before.

11.
Opt Express ; 30(11): 19904-19921, 2022 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-36221754

RESUMEN

We demonstrate a free-running single-cavity dual-comb optical parametric oscillator (OPO) pumped by a single-cavity dual-comb solid-state laser. The OPO ring cavity contains a single periodically-poled MgO-doped LiNbO3 (PPLN) crystal. Each idler beam has more than 245-mW average power at 3550 nm and 3579 nm center wavelengths (bandwidth 130 nm). The signal beams are simultaneously outcoupled with more than 220 mW per beam at 1499 nm and 1496 nm center wavelength. The nominal repetition rate is 80 MHz, while the repetition rate difference is tunable and set to 34 Hz. To evaluate the feasibility of using this type of source for dual-comb applications, we characterize the noise and coherence properties of the OPO signal beams. We find ultra-low relative intensity noise (RIN) below -158 dBc/Hz at offset frequencies above 1 MHz. A heterodyne beat note measurement with a continuous wave (cw) laser is performed to determine the linewidth of a radio-frequency (RF) comb line. We find a full-width half-maximum (FWHM) linewidth of around 400 Hz. Moreover, the interferometric measurement between the two signal beams reveals a surprising property: the center of the corresponding RF spectrum is always near zero frequency, even when tuning the pump repetition rate difference or the OPO cavity length. We explain this effect theoretically and discuss its implications for generating stable low-noise idler combs suitable for high-sensitivity mid-infrared dual-comb spectroscopy (DCS).

12.
Br J Dermatol ; 187(2): 141-148, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-34549421

RESUMEN

Chronic wounds have a debilitating effect on the quality of life of many individuals, and the large economic impact on health system budgets warrants greater attention in policy making and condition management than is currently evident. The aim of this narrative review is to summarize the nature and extent of the chronic wound problem that confronts health systems across the world. The first section is used to highlight the underlying epidemiology relating to chronic wounds, while the second explores the economic costs associated with them and the relative efficiency of measures designed to manage them.


Asunto(s)
Calidad de Vida , Heridas y Lesiones , Humanos , Heridas y Lesiones/epidemiología , Heridas y Lesiones/terapia
13.
MMWR Morb Mortal Wkly Rep ; 71(10): 365-370, 2022 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-35271561

RESUMEN

In the United States, annual vaccination against seasonal influenza is recommended for all persons aged ≥6 months except when contraindicated (1). Currently available influenza vaccines are designed to protect against four influenza viruses: A(H1N1)pdm09 (the 2009 pandemic virus), A(H3N2), B/Victoria lineage, and B/Yamagata lineage. Most influenza viruses detected this season have been A(H3N2) (2). With the exception of the 2020-21 season, when data were insufficient to generate an estimate, CDC has estimated the effectiveness of seasonal influenza vaccine at preventing laboratory-confirmed, mild/moderate (outpatient) medically attended acute respiratory infection (ARI) each season since 2004-05. This interim report uses data from 3,636 children and adults with ARI enrolled in the U.S. Influenza Vaccine Effectiveness Network during October 4, 2021-February 12, 2022. Overall, vaccine effectiveness (VE) against medically attended outpatient ARI associated with influenza A(H3N2) virus was 16% (95% CI = -16% to 39%), which is considered not statistically significant. This analysis indicates that influenza vaccination did not reduce the risk for outpatient medically attended illness with influenza A(H3N2) viruses that predominated so far this season. Enrollment was insufficient to generate reliable VE estimates by age group or by type of influenza vaccine product (1). CDC recommends influenza antiviral medications as an adjunct to vaccination; the potential public health benefit of antiviral medications is magnified in the context of reduced influenza VE. CDC routinely recommends that health care providers continue to administer influenza vaccine to persons aged ≥6 months as long as influenza viruses are circulating, even when VE against one virus is reduced, because vaccine can prevent serious outcomes (e.g., hospitalization, intensive care unit (ICU) admission, or death) that are associated with influenza A(H3N2) virus infection and might protect against other influenza viruses that could circulate later in the season.


Asunto(s)
Subtipo H3N2 del Virus de la Influenza A/inmunología , Virus de la Influenza A/inmunología , Vacunas contra la Influenza/administración & dosificación , Gripe Humana/prevención & control , Eficacia de las Vacunas , Adolescente , Adulto , Anciano , Niño , Preescolar , Humanos , Lactante , Subtipo H1N1 del Virus de la Influenza A/inmunología , Virus de la Influenza B/inmunología , Persona de Mediana Edad , Vigilancia de la Población , Estaciones del Año , Estados Unidos/epidemiología , Vacunación
14.
Neuroradiology ; 64(11): 2207-2211, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35969251

RESUMEN

Computed tomography (CT)-guided percutaneous biopsy of deep-seated head and neck lesions can be a less invasive and equally effective alternative to surgical techniques. There are multiple approaches for needle biopsy that target varying spaces within the head and neck while successfully avoiding critical anatomy. In the paramaxillary approach, the needle is advanced through the infrazygomatic buccal space, in between the maxilla and mandible. In this study, we examine the safety and diagnostic yield of FNA without core needle biopsy performed via the paramaxillary approach in 19 patients yielding 20 fine needle aspirates between 2014 and 2022. Of the fine needle aspirates, 85.0% (17/20) were diagnostic. Concordant histopathologic diagnosis was obtained in 100% (17/17) diagnostic fine needle aspirates. There were no postprocedural complications.


Asunto(s)
Neoplasias de Cabeza y Cuello , Cuello , Biopsia con Aguja Fina , Cabeza/diagnóstico por imagen , Cabeza/patología , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Neoplasias de Cabeza y Cuello/patología , Humanos , Cuello/patología , Tomografía Computarizada por Rayos X/métodos
15.
Cereb Cortex ; 31(12): 5449-5459, 2021 10 22.
Artículo en Inglés | MEDLINE | ID: mdl-34180511

RESUMEN

The frontoparietal semantic network, encompassing the inferior frontal gyrus and the posterior middle temporal cortex, is considered to be involved in semantic control processes. The explicit versus implicit nature of these control processes remains however poorly understood. The present study examined this question by assessing regional brain responses to the semantic attributes of an unattended stream of auditory words while participants' top-down attentional control processes were absorbed by a demanding visual search task. Response selectivity to semantic aspects of verbal stimuli was assessed via a functional magnetic resonance imaging response adaptation paradigm. We observed that implicit semantic processing of an unattended verbal stream recruited not only unimodal and amodal cortices in posterior supporting semantic knowledge areas, but also inferior frontal and posterior middle temporal areas considered to be part of the semantic control network. These results indicate that frontotemporal semantic networks support incidental semantic (control) processes.


Asunto(s)
Web Semántica , Semántica , Mapeo Encefálico , Humanos , Corteza Prefrontal/fisiología , Lóbulo Temporal/diagnóstico por imagen , Lóbulo Temporal/fisiología
16.
Clin Radiol ; 77(3): 231-235, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35022132

RESUMEN

AIM: To follow-up previous work evaluating incidental findings of COVID-19 signs on computed tomography (CT) images of major trauma patients to include the second wave prior to any major effects from vaccines. MATERIALS AND METHODS: The study population included all patients admitted following major trauma between 1 January 2020 and 28 February 2021 with CT including the lungs (n=1776). Major trauma patients admitted pre-COVID-19 from alternate months from January 2019 to November 2019 comprised a control group (n=837). The assessing radiologists were blinded to the time period and used double reading in consensus to determine if the patient had signs of COVID-19. Lung appearances were classified as no evidence of COVID-19, minor signs, or major signs. RESULTS: The method successfully tracked the second wave of the COVID-19 pandemic in London. The estimated population affected by the disease based on those with major signs was similar to estimates of the proportion of the population in London with antibodies (around 30% by end February 2021) and the total of major and minor signs produced a much higher figure of 68%, which may include all those with both antibody and just T-cell responses. CONCLUSIONS: Incidental findings on CT from major trauma patients may provide a novel and sensitive way of tracking the virus. It is recommended that all major trauma units include a simple question on signs of COVID-19 to provide an early warning system for further waves.


Asunto(s)
COVID-19/epidemiología , Pulmón/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Heridas y Lesiones/diagnóstico por imagen , Heridas y Lesiones/epidemiología , Anciano de 80 o más Años , COVID-19/diagnóstico por imagen , Comorbilidad , Femenino , Humanos , Hallazgos Incidentales , Londres/epidemiología , Masculino , Persona de Mediana Edad , Pandemias , Prevalencia , Reino Unido/epidemiología
17.
Am J Otolaryngol ; 43(3): 103404, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35246319

RESUMEN

Benign bony tumors of the skull base and paranasal sinuses are uncommon entities, with an overall higher incidence in males. Benign bony tumors may lead to local expansion with resultant mass effect of potentially critical structures. Some benign bony tumors may undergo malignant transformation. This article reviews the presentation and management of benign bone tumors of the skull base and paranasal sinuses with special consideration to involvement of the adjacent orbit, intracranial and critical neurovascular structures. This review covers tumor incidence, location, gross and histologic appearance as well as radiographic findings, treatment, and recurrence rates. Tumors discussed in this article include osteochondromas, osteomas, osteoid osteomas, aneurysmal bone cysts, fibrous dysplasia, giant cell tumors, cemento-ossifying fibroma, ameloblastic fibro-odontoma, ecchordosis physaliphora, chondromyxoid fibroma, primary chronic osteomyelitis, primary chronic osteomyelitis, osteochondromyxoma, and dense bone islands.


Asunto(s)
Osteoma , Osteomielitis , Neoplasias de los Senos Paranasales , Senos Paranasales , Neoplasias de la Base del Cráneo , Humanos , Masculino , Órbita , Osteoma/diagnóstico por imagen , Osteoma/cirugía , Neoplasias de los Senos Paranasales/diagnóstico por imagen , Neoplasias de los Senos Paranasales/patología , Neoplasias de los Senos Paranasales/terapia , Senos Paranasales/patología , Base del Cráneo/diagnóstico por imagen , Neoplasias de la Base del Cráneo/diagnóstico por imagen , Neoplasias de la Base del Cráneo/terapia
18.
West Afr J Med ; 39(8): 852-858, 2022 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-36066508

RESUMEN

BACKGROUND: Over two-thirds of the world's population cannot access surgery when needed. Interventions to address this gap have primarily focused on surgical training and ministry-level surgical planning. However, patients more commonly cite cost-rather than governance or surgeon availability-as their primary access barrier. We undertook a randomized, controlled trial (RCT) to evaluate the effect on compliance with scheduled surgical appointments of addressing this barrier through a cash transfer. METHODS: 453 patients who were deemed surgical candidates by a nursing screening team in Guinea, West Africa, were randomized into three study arms: control, conditional cash transfer, and labeled unconditional cash transfer. Patients in the conditional cash transfer group were given a cash transfer to cover their transportation costs once they had been discharged from care. Patients in the unconditional arm were given a cash transfer to cover their transportation costs before they left their homes to get care. Arrival to a scheduled surgical appointment was the primary outcome. The study was performed in conjunction with Mercy Ships. RESULTS: The overall no-show rate was five-fold lower in Guinea than previously published estimates, likely due to changes in the patient selection and retention process, leading to an underpowered study. In a post-hoc analysis, which included non-randomized patients, patients in the control group and the conditional cash transfer group demonstrated no effect from the cash transfer. Patients in the unconditional cash transfer group were significantly less likely to arrive for their scheduled appointment. Subgroup analysis suggested that actual receipt of the unconditional cash transfer, instead of a lapse in the transfer mechanism, was associated with failure to show. CONCLUSION: We find that cash transfers are feasible for surgical patients in a low-resource setting, but that unconditional transfers may have negative effects on compliance. Although demand-side barriers are large for surgical patients in low-resource settings, interventions to address them must be designed with care. CONTEXTE: Plus des deux tiers de la population mondiale n'ont pas accès à la chirurgie lorsqu'ils en ont besoin. Les interventions visant à combler cette lacune ont principalement sur la formation chirurgicale et la planification chirurgicale au niveau ministériel. Cependant, les patients citent plus souvent le coût - plutôt que la gouvernance ou la disponibilité des chirurgiens - comme étant leur principal obstacle à l'accès. Nous avons entrepris un essai contrôlé randomisé (ECR) pour évaluer l'effet sur le respect des rendez-vous chirurgicaux programmés en s'attaquant à cet barrière par un transfert d'argent. MÉTHODES: 453 patients considérés comme des candidats à la chirurgie par une équipe de dépistage infirmière en Guinée, Afrique de l'Ouest, ont été répartis de manière aléatoire dans trois bras d'étude : contrôle, transfert monétaire conditionnel et transfert monétaire non transfert monétaire inconditionnel. Les patients du groupe de transfert monétaire conditionnel ont reçu un transfert d'argent pour couvrir leurs frais de transport une fois qu'ils étaient sortis des soins. Les patients du groupe de transfert inconditionnel recevaient un transfert en espèces pour couvrir leurs frais de transport avant de quitter leur domicile pour recevoir des soins. L'arrivée à un rendez-vous chirurgical programmé était le résultat principal. L'étude a été réalisée en collaboration avec Mercy Ships. RÉSULTATS: Le taux global de non-présentation était cinq fois inférieur en Guinée que les estimations publiées précédemment, probablement en raison de changements dans le processus de sélection et de rétention des patients, ce qui a conduit à une étude insuffisamment puissante. Dans une analyse post-hoc, qui incluait des patients non randomisés, les patients dans le groupe de contrôle et dans le groupe de transfert conditionnel n'ont montré aucun effet du transfert d'argent. Les patients du groupe de transfert d'argent sans condition étaient significativement moins susceptibles d'arriver pour leur rendez-vous prévu. L'analyse des sous-groupes suggère que la réception effective du transfert monétaire inconditionnel plutôt d'un erreur en mécanisme de transfert, était associé à l'absence de rendez-vous. CONCLUSION: Nous constatons que les transferts d'argent sont possibles pour les patients chirurgicaux dans un environnement à faibles ressources, mais que les transferts inconditionnels peuvent avoir des effets négatifs sur l'observance. Bien que les obstacles liés à la demande sont importants pour les patients opérés dans des contextes à faibles ressources, les doivent être conçues avec soin. MOTS-CLÉS: Transferts monétaires, Chirurgie, Chirurgie globale, Guinée, Interventions financières, Utilisation chirurgicale, Essai contrôlé randomisé.


Asunto(s)
Procedimientos Quirúrgicos Operativos , África Occidental , Humanos , Procedimientos Quirúrgicos Operativos/economía
19.
Clin Infect Dis ; 73(5): 802-807, 2021 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-33590002

RESUMEN

BACKGROUND: Although multiple respiratory viruses circulate in humans, few studies have compared the incidence of different viruses across the life course. We estimated the incidence of outpatient illness due to 12 different viruses during November 2018 through April 2019 in a fully enumerated population. METHODS: We conducted active surveillance for ambulatory care visits for acute respiratory illness (ARI) among members of Kaiser Permanente Washington (KPWA). Enrolled patients provided respiratory swab specimens which were tested for 12 respiratory viruses using reverse transcription polymerase chain reaction (RT-PCR). We estimated the cumulative incidence of infection due to each virus overall and by age group. RESULTS: The KPWA population under surveillance included 202 562 individuals, of whom 2767 (1.4%) were enrolled in the study. Influenza A(H3N2) was the most commonly detected virus, with an overall incidence of 21 medically attended illnesses per 1000 population; the next most common viruses were influenza A(H1N1) (18 per 1000), coronaviruses (13 per 1000), respiratory syncytial virus (RSV, 13 per 1000), and rhinovirus (9 per 1000). RSV was the most common cause of medically attended ARI among children aged 1-4 years; coronaviruses were the most common among adults aged ≥65 years. CONCLUSIONS: Consistent with other studies focused on single viruses, we found that influenza and RSV were major causes of acute respiratory illness in persons of all ages. In comparison, coronaviruses and rhinovirus were also important pathogens. Prior to the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), coronaviruses were the second-most common cause of medically attended ARI during the 2018/19 influenza season.


Asunto(s)
COVID-19 , Subtipo H1N1 del Virus de la Influenza A , Gripe Humana , Virus Sincitial Respiratorio Humano , Infecciones del Sistema Respiratorio , Adulto , Niño , Humanos , Incidencia , Lactante , Subtipo H3N2 del Virus de la Influenza A , Gripe Humana/epidemiología , Infecciones del Sistema Respiratorio/epidemiología , SARS-CoV-2 , Estaciones del Año
20.
Opt Express ; 29(22): 36321-36327, 2021 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-34809045

RESUMEN

We present a high power optical parametric oscillator (OPO) synchronously pumped by the second-harmonic of a modelocked 1030-nm thin-disk laser (TDL) oscillator. The OPO delivers an average power of 51.1 W around degeneracy (1030 nm) with a 10.2-MHz repetition-rate. After extra-cavity dispersion compensation using dispersive mirrors, we obtain a pulse duration of 169 fs, which is 4.6× shorter than the TDL pulse duration of 770 fs. The TDL has 250 W average power, which is converted to 215 W at the second-harmonic. Hence, the OPO exhibits a high photon conversion efficiency of 47% (ratio of signal photons to 515-nm pump photons). Moreover, the OPO generates a peak power of 26.2 MW, which is very similar to the 28.0-MW peak power of the TDL. To facilitate continuous tuning around degeneracy and convenient extraction of the pump and idler beams, the OPO is operated in a noncollinear configuration. A linear cavity configuration was chosen since it offers easy alignment and straightforward cavity length tuning. To the best of our knowledge, this source has the highest average power generated by any ultrafast OPO, and the shortest pulse duration for any >5-W OPO. This result is an important step to adding wavelength tunability to high power Yb-based laser sources without the complexity of either laser or parametric amplifier systems.

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