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1.
Nature ; 585(7825): 379-382, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32939065

RESUMEN

The field of plasmonics, which studies the resonant interactions of electromagnetic waves and free electrons in solid-state materials1, has yet to be put to large-scale commercial application2 owing to the large amount of loss that usually occurs in plasmonic materials3. Organic light-emitting devices (OLEDs)4-7 have been incorporated into billions of commercial products because of their good colour saturation, versatile form factor8 and low power consumption9, but could still be improved in terms of efficiency and stability. Although OLEDs incorporating organic phosphors achieve an internal charge-to-light conversion of unity10, their refractive index contrast reduces the observable fraction of photons outside the device to around 25 per cent11-13. Further, during OLED operation, a localized buildup of slow-decaying14 triplet excitons and charges15 gradually reduces the brightness of the device in a process called ageing16,17, which can result in 'burn-in' effects on the display. Simultaneously improving device efficiency and stability is of paramount importance for OLED technology. Here we demonstrate an OLED that uses the decay rate enhancement18 of a plasmonic system to increase device stability, while maintaining efficiency by incorporating a nanoparticle-based out-coupling scheme to extract energy from the plasmon mode. Using an archetypal phosphorescent emitter, we achieve a two-fold increase in operational stability at the same brightness as a reference conventional device while simultaneously extracting 16 per cent of the energy from the plasmon mode as light. Our approach to increasing OLED stability avoids material-specific designs19-22 and is applicable to all commercial OLEDs that are currently used for lighting panels, televisions and mobile displays.

2.
Nature ; 571(7766): 500-504, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31292546

RESUMEN

Two fossilized human crania (Apidima 1 and Apidima 2) from Apidima Cave, southern Greece, were discovered in the late 1970s but have remained enigmatic owing to their incomplete nature, taphonomic distortion and lack of archaeological context and chronology. Here we virtually reconstruct both crania, provide detailed comparative descriptions and analyses, and date them using U-series radiometric methods. Apidima 2 dates to more than 170 thousand years ago and has a Neanderthal-like morphological pattern. By contrast, Apidima 1 dates to more than 210 thousand years ago and presents a mixture of modern human and primitive features. These results suggest that two late Middle Pleistocene human groups were present at this site-an early Homo sapiens population, followed by a Neanderthal population. Our findings support multiple dispersals of early modern humans out of Africa, and highlight the complex demographic processes that characterized Pleistocene human evolution and modern human presence in southeast Europe.


Asunto(s)
Cuevas , Fósiles , Cráneo/anatomía & histología , Animales , Evolución Biológica , Grecia , Humanos , Hombre de Neandertal/anatomía & histología , Hombre de Neandertal/clasificación , Análisis de Componente Principal , Datación Radiométrica , Factores de Tiempo
3.
J Hum Nutr Diet ; 36(3): 687-696, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36239126

RESUMEN

BACKGROUND: There is increasing interest in the assessment of health-related quality of life (QoL) in the care of patients treated with home parenteral nutrition (HPN). However, it is not known whether healthcare professionals (HCPs) have embedded QoL assessment into routine clinical practice in line with current guidelines to favour a more holistic approach to HPN care. The aim of this study was to assess knowledge, current practice and the opinions of HCPs regarding QoL in care of patients on HPN. METHODS: An online survey was distributed via email to HCPs working with HPN patients throughout England, Scotland, Wales and Northern Ireland. Participants were identified using a mailing list for the British Intestinal Failure Alliance, a specialist group within the British Association for Parenteral and Enteral Nutrition. RESULTS: The survey was completed by 67 professionals comprising 24 dietitians, 17 nurses, 14 gastroenterologists, 6 pharmacists, 5 surgeons and 1 psychologist. Of these, 54 (80%) participants agreed that the measurement of QoL is useful. In contrast, 38 (57%) of all participants, including 27 (50%) of those participants who agreed that the measurement of QoL was useful, never measured QoL. Knowledge of QoL literature was rated as poor or very poor by 27 (40%) participants. CONCLUSIONS: Despite the perceived usefulness and importance of QoL assessment, very few HCPs embed it into clinical practice. Knowledge of QoL literature and QoL tools is variable, and there is significant variability in QoL practice. This is clear in terms of the frequency of QoL assessments and heterogeneity in methodology. In contrast, there was almost unanimous agreement that the complications associated with HPN contribute to poorer QoL. There is a need for specific, evidence-based, clinical practice guidelines detailing how to define and measure QoL in this patient population.


Asunto(s)
Nutrición Parenteral en el Domicilio , Calidad de Vida , Humanos , Nutrición Parenteral en el Domicilio/métodos , Encuestas y Cuestionarios , Inglaterra , Atención a la Salud
4.
Audiol Neurootol ; 27(6): 437-448, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35439753

RESUMEN

INTRODUCTION: Cochlear implant (CI) recipients with normal hearing (NH) in the contralateral ear experience a significant improvement in sound source localization when listening with the CI in combination with their NH-ear (CI + NH) as compared to with the NH-ear alone. The improvement in localization is primarily due to sensitivity to interaural level differences (ILDs). Sensitivity to interaural timing differences (ITDs) may be limited by auditory aging, frequency-to-place mismatches, the signal coding strategy, and duration of CI use. The present report assessed the sensitivity of ILD and ITD cues in CI + NH listeners who were recipients of long electrode arrays that provide minimal frequency-to-place mismatches and were mapped with a coding strategy that presents fine structure cues on apical channels. METHODS: Sensitivity to ILDs and ITDs for localization was assessed using broadband noise (BBN), as well as high-pass (HP) and low-pass (LP) filtered noise for adult CI + NH listeners. Stimuli were 200-ms noise bursts presented from 11 speakers spaced evenly over an 180° arc. Performance was quantified in root-mean-squared error and response patterns were analyzed to evaluate the consistency, accuracy, and side bias of the responses. Fifteen listeners completed the task at the 2-year post-activation visit; seven listeners repeated the task at a later annual visit. RESULTS: Performance at the 2-year visit was best with the BBN and HP stimuli and poorer with the LP stimulus. Responses to the BBN and HP stimuli were significantly correlated, consistent with the idea that CI + NH listeners primarily use ILD cues for localization. For the LP stimulus, some listeners responded consistently and accurately and with limited side bias, which may indicate sensitivity to ITD cues. Two of the 7 listeners who repeated the task at a later annual visit experienced a significant improvement in performance with the LP stimulus, which may indicate that sensitivity to ITD cues may improve with long-term CI use. CONCLUSIONS: CI recipients with a NH-ear primarily use ILD cues for sound source localization, though some may use ITD cues as well. Sensitivity to ITD cues may improve with long-term CI listening experience.


Asunto(s)
Implantación Coclear , Implantes Cocleares , Localización de Sonidos , Estimulación Acústica , Localización de Sonidos/fisiología , Audición
5.
Proc Natl Acad Sci U S A ; 115(52): E12144-E12152, 2018 12 26.
Artículo en Inglés | MEDLINE | ID: mdl-30541890

RESUMEN

Creative cognition requires mental exploration of remotely connected concepts while suppressing dominant ones. Across four experiments using different samples of participants, we provide evidence that right temporal alpha oscillations play a crucial role in inhibiting habitual thinking modes, thereby paving the way for accessing more remote ideas. In the first experiment, participants completed the compound remote associate task (RAT) in three separate sessions: during right temporal alpha (10 Hz) transcranial alternating current brain stimulation (tACS), left temporal alpha tACS, and sham tACS. Participants performed better under right tACS only on RAT items in which two of the three words shared misleading semantic associations. In the second experiment, we measured EEG while the participants solved RAT items with or without shared misleading associations. We observed an increase in right temporal alpha power when participants correctly solved RAT items with misleading semantic associations. The third experiment demonstrated that while solving divergent thinking tasks participants came up with more remote ideas when stimulated by right temporal alpha tACS. In the fourth experiment, we found that participants showed higher right temporal alpha power when generating more remote uses for common objects. These studies altogether indicate that right temporal alpha oscillations may support creativity by acting as a neural mechanism for an active inhibition of obvious semantic associations.


Asunto(s)
Encéfalo/fisiología , Adolescente , Adulto , Ritmo alfa , Cognición , Creatividad , Electroencefalografía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pensamiento , Estimulación Transcraneal de Corriente Directa , Adulto Joven
6.
J Am Chem Soc ; 142(2): 900-906, 2020 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-31875398

RESUMEN

A new approach for room-temperature 17O enrichment of zeolites reveals a surprisingly dynamic and labile framework, where rapid and reversible bond breaking takes place. 17O NMR spectroscopy shows that although O sites in both framework Si-O-Al and Si-O-Si linkages are enriched simply on exposure to H217O(l), the enrichment of Si-O-Al species is more rapid, with a more uniform framework enrichment observed at longer durations. We demonstrate that this unexpected enrichment can be observed for two different framework topologies and for Na-exchanged (i.e., nonacidic) zeolites, as well as their protonic forms, confirming that the Brønsted acid proton is not necessary for isotopic exchange into the framework. This work not only offers new opportunities for structural characterization of these chemically and industrially important materials using NMR spectroscopy but suggests that further investigation of the rate and position of enrichment in zeolite frameworks could provide new insight into their chemical reactivity and their stability in aqueous-based applications such as ion exchange and catalysis.

7.
Epilepsia ; 61(8): 1627-1637, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32658343

RESUMEN

OBJECTIVE: Compared to other seizure types, generalized tonic-clonic (GTC) seizures may be disproportionately related to increased morbidity, and reducing seizure frequency could translate into improvements across measures of morbidity in medically treated patients with drug-resistant epilepsy (DRE). The primary objective of this analysis was to quantify the burden of patients with DRE who experience GTC seizures (GTC+) compared to patients with DRE who do not experience GTC seizures (GTC-). METHODS: Adult patients from the Cleveland Clinic Epilepsy Center-Neurological Institute from 2012-2016 with DRE with epilepsy for at least 1 year were eligible for inclusion and were divided into GTC ± groups based on whether the patient had experienced a GTC seizure in the year preceding the first visit. Epilepsy duration, comorbidities, antiepileptic drug use, patient-reported outcomes (PROs) and seizure type, frequency, and etiology were captured. Generalized linear models, negative binomial regression, logistic regression, and linear regression were used as appropriate for multivariate analyses. RESULTS: A total of 379 patients met inclusion criteria and had data at 1-year follow-up after their baseline visit (192 GTC+ and 187 GTC-). Although DRE patients experiencing GTC seizures had fewer seizures per day over the preceding 6 months than those not experiencing GTC seizures, seizure severity and levels of depression and anxiety were greater. GTC+ patients who reported five or more seizures in the preceding 4 weeks had 82% lower odds (1-0.18 = 0.82) of working than patients with no seizures. SIGNIFICANCE: Patients with DRE experience a significant burden and decreased quality of life. Multivariate analysis is necessary to understand the complex relationship between seizure type, frequency, and impact on health-related quality of life (HRQoL) and changes over time. Effective treatments to reduce the burden for DRE patients who experience GTC seizures continue to be needed.


Asunto(s)
Epilepsia Refractaria/fisiopatología , Epilepsia/fisiopatología , Calidad de Vida , Convulsiones/fisiopatología , Adulto , Anticonvulsivantes/uso terapéutico , Ansiedad/psicología , Costo de Enfermedad , Depresión/psicología , Epilepsia Refractaria/tratamiento farmacológico , Epilepsia Refractaria/psicología , Epilepsia/tratamiento farmacológico , Epilepsia/psicología , Femenino , Humanos , Modelos Lineales , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Medición de Resultados Informados por el Paciente , Convulsiones/psicología , Índice de Severidad de la Enfermedad , Adulto Joven
8.
J Med Internet Res ; 18(4): e87, 2016 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-27154301

RESUMEN

BACKGROUND: Emerging technologies (ie, mobile phones, Internet) may be effective tools for promoting physical activity (PA). However, few interventions have provided effective means to enhance social support through these platforms. Face-to-face programs that use group dynamics-based principles of behavior change have been shown to be highly effective in enhancing social support through promoting group cohesion and PA, but to date, no studies have examined their effects in Web-based programs. OBJECTIVE: The aim was to explore proof of concept and test the efficacy of a brief, online group dynamics-based intervention on PA in a controlled experiment. We expected that the impact of the intervention on PA would be moderated by perceptions of cohesion and the partner's degree of presence in the online media. METHODS: Participants (n=135) were randomized into same-sex dyads and randomly assigned to one of four experimental conditions: standard social support (standard), group dynamics-based-high presence, group dynamics-based-low presence, or individual control. Participants performed two sets of planking exercises (pre-post). Between sets, participants in partnered conditions interacted with a virtual partner using either a standard social support app or a group dynamics-based app (group dynamics-based-low presence and group dynamics-based-high presence), the latter of which they participated in a series of online team-building exercises. Individual participants were given an equivalent rest period between sets. To increase presence during the second set, participants in the group dynamics-based-high presence group saw a live video stream of their partner exercising. Perceptions of cohesion were measured using a modified PA Group Environment Questionnaire. Physical activity was calculated as the time persisted during set 2 after controlling for persistence in set 1. RESULTS: Perceptions of cohesion were higher in the group dynamics-based-low presence (overall mean 5.81, SD 1.04) condition compared to the standard (overall mean 5.04, SD 0.81) conditions ( P=.006), but did not differ between group dynamics-based-low presence and group dynamics-based-high presence (overall mean 5.42, SD 1.07) conditions ( P=.25). Physical activity was higher in the high presence condition (mean 64.48, SD 20.19, P=.01) than all other conditions (mean 53.3, SD 17.35). CONCLUSIONS: A brief, online group dynamics-based intervention may be an effective method of improving group cohesion in virtual PA groups. However, it may be insufficient on its own to improve PA.


Asunto(s)
Ejercicio Físico , Promoción de la Salud/métodos , Internet , Apoyo Social , Adolescente , Femenino , Humanos , Masculino , Encuestas y Cuestionarios , Adulto Joven
9.
Nat Mater ; 13(11): 1039-43, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25282507

RESUMEN

Triplet excitons are ubiquitous in organic optoelectronics, but they are often an undesirable energy sink because they are spin-forbidden from emitting light and their high binding energy hinders the generation of free electron-hole pairs. Harvesting their energy is consequently an important technological challenge. Here, we demonstrate direct excitonic energy transfer from 'dark' triplets in the organic semiconductor tetracene to colloidal PbS nanocrystals, thereby successfully harnessing molecular triplet excitons in the near infrared. Steady-state excitation spectra, supported by transient photoluminescence studies, demonstrate that the transfer efficiency is at least (90 ± 13)%. The mechanism is a Dexter hopping process consisting of the simultaneous exchange of two electrons. Triplet exciton transfer to nanocrystals is expected to be broadly applicable in solar and near-infrared light-emitting applications, where effective molecular phosphors are lacking at present. In particular, this route to 'brighten' low-energy molecular triplet excitons may permit singlet exciton fission sensitization of conventional silicon solar cells.

10.
Philos Trans A Math Phys Eng Sci ; 373(2044)2015 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-25987573

RESUMEN

Magnetic field effects provide a convenient and specific probe of singlet exciton fission within optoelectronic devices. Here, we demonstrate that this tool may also be applied to screen potential fission material candidates in solution. We characterize the phenomenon in diphenyl tetracene (DPT), which shows strong fluorescence modulation and the expected field dependence in its transient decay as a function of concentration. Solution measurements may also be used to test for the presence of an intermediate charge transfer state, but we observe no changes to the field dependence of DPT singlet exciton fission in toluene relative to chloroform.

11.
Acc Chem Res ; 46(6): 1300-11, 2013 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-23611026

RESUMEN

Singlet exciton fission, a process that generates two excitons from a single photon, is perhaps the most efficient of the various multiexciton-generation processes studied to date, offering the potential to increase the efficiency of solar devices. But its unique characteristic, splitting a photogenerated singlet exciton into two dark triplet states, means that the empty absorption region between the singlet and triplet excitons must be filled by adding another material that captures low-energy photons. This has required the development of specialized device architectures. In this Account, we review work to develop devices that harness the theoretical benefits of singlet exciton fission. First, we discuss singlet fission in the archetypal material, pentacene. Pentacene-based photovoltaic devices typically show high external and internal quantum efficiencies. They have enabled researchers to characterize fission, including yield and the impact of competing loss processes, within functional devices. We review in situ probes of singlet fission that modulate the photocurrent using a magnetic field. We also summarize studies of the dissociation of triplet excitons into charge at the pentacene-buckyball (C60) donor-acceptor interface. Multiple independent measurements confirm that pentacene triplet excitons can dissociate at the C60 interface despite their relatively low energy. Because triplet excitons produced by singlet fission each have no more than half the energy of the original photoexcitation, they limit the potential open circuit voltage within a solar cell. Thus, if singlet fission is to increase the overall efficiency of a solar cell and not just double the photocurrent at the cost of halving the voltage, it is necessary to also harvest photons in the absorption gap between the singlet and triplet energies of the singlet fission material. We review two device architectures that attempt this using long-wavelength materials: a three-layer structure that uses long- and short-wavelength donors and an acceptor and a simpler, two-layer combination of a singlet-fission donor and a long-wavelength acceptor. An example of the trilayer structure is singlet fission in tetracene with copper phthalocyanine inserted at the C60 interface. The bilayer approach includes pentacene photovoltaic cells with an acceptor of infrared-absorbing lead sulfide or lead selenide nanocrystals. Lead selenide nanocrystals appear to be the most promising acceptors, exhibiting efficient triplet exciton dissociation and high power conversion efficiency. Finally, we review architectures that use singlet fission materials to sensitize other absorbers, thereby effectively converting conventional donor materials to singlet fission dyes. In these devices, photoexcitation occurs in a particular molecule and then energy is transferred to a singlet fission dye where the fission occurs. For example, rubrene inserted between a donor and an acceptor decouples the ability to perform singlet fission from other major photovoltaic properties such as light absorption.

12.
Emotion ; 24(1): 164-176, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37338429

RESUMEN

Understanding and sharing others' emotions (i.e., empathy) requires the ability to manage one's own emotions (i.e., emotion regulation). Indeed, empirical evidence suggests that empathy and emotion regulation are related. This evidence is largely based on self-report measures of both constructs. The current study examined how task measures that assess processes related to empathy are associated with self-reported emotion dysregulation in a young adult sample. An eye-tracking-based perspective-taking task was used as a proxy measure of cognitive empathy. A spontaneous facial mimicry (SFM) task, wherein the activation of the Zygomaticus Major and the Corrugator Supercilii was measured during the passive viewing of happy and angry faces, was used as a proxy measure of affective empathy. The perspective-taking task metric showed a negative relationship with emotion dysregulation. The overall SFM metric was not significantly associated with emotion dysregulation. Follow-up analyses revealed that SFM for angry faces was inversely proportional to emotion dysregulation; no such relationship was observed for SFM for happy faces. These findings build upon prior work by demonstrating a positive relationship between adaptive emotion regulation and a behavioral measure of cognitive empathy. The findings for affective empathy are suggestive of a valence-specific relationship between SFM and emotion regulation. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Asunto(s)
Emociones , Empatía , Adulto Joven , Humanos , Emociones/fisiología , Ira , Felicidad , Músculos Faciales/fisiología , Expresión Facial
13.
BMJ Open ; 14(1): e082163, 2024 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-38184307

RESUMEN

BACKGROUND: Home parenteral nutrition (HPN) refers to the intravenous administration of macronutrients, micronutrients and fluid. The aims of treatment are to increase survival and improve quality of life (QoL). However, patients struggle with physiological symptoms, time-consuming invasive therapy and an increased occurrence of depression and social isolation. Our aim is to understand how HPN impacts the QoL of patients, and the contribution played by the complications of treatment, for example, liver disease. METHODS AND ANALYSIS: A multicentre, longitudinal, observational study will be conducted using routinely collected clinical data. Participants will also be asked to complete three QoL questionnaires (EuroQol-5 Dimensions, Short Form 36 and HPN-QoL) at baseline and 12 months. The primary outcome is mean change in QoL scores over 12 months. Secondary outcomes include how factors including liver function, gut microbiota, number of infusions of PN per week, nutritional composition of PN and nutritional status impact on QoL scores. ETHICS AND DISSEMINATION: Ethical approval was obtained from HRA and Health and Care Research Wales Research Ethics Committee (21/SC/0316). The study was eligible for portfolio adoption, Central Portfolio Management System ID 50506. Results will be disseminated through peer-reviewed scientific journals and presented at national and international meetings.


Asunto(s)
Insuficiencia Intestinal , Nutrición Parenteral en el Domicilio , Humanos , Calidad de Vida , Administración Intravenosa , Comités de Ética en Investigación , Estudios Observacionales como Asunto , Estudios Multicéntricos como Asunto
14.
Artículo en Inglés | MEDLINE | ID: mdl-38541333

RESUMEN

The work environment for building workers in Australia's Northern Territory (NT) is characterised by concerningly high rates of distress and suicide at both a jurisdictional and an industry level. Work-related psychosocial hazards are known antecedents of work-related distress and suicide, and more research is required to understand how these hazards impact workers in this unique building context. This paper examines the unique work environment in the NT building industry by comparing psychosocial hazards in the NT with those in the broader Australian building and construction industry. When comparing 330 NT self-report survey responses about psychosocial hazards in the workplace to 773 broader Australian building industry responses, supervisor task conflict for NT workers was more concerning, at 10.9% higher than the broader Australian cohort. Within the NT sample, comparisons between fly-in and fly-out/drive-in and drive-out (FIFO/DIDO) workers and non-FIFO/DIDO workers were also performed to determine specific local psychosocial hazards. When comparing FIFO/DIDO workers' responses to their NT peers, role overload and supervisor task conflict were significantly higher, and co-worker and supervisor support were lower. In FIFO/DIDO environments, praise and recognition, procedural justice, and change consultation were at concerningly lower averages than the broader NT building and construction industry. These results suggest that the NT building and construction industry, and particularly FIFO/DIDO operations, require greater resourcing, investment, and focus on workplace mental health initiatives to improve the work environment and wellbeing of this workforce and mitigate hazards that can lead to distress and the high rates of occupational suicide found in this jurisdiction and industry.


Asunto(s)
Industria de la Construcción , Estrés Laboral , Suicidio , Humanos , Northern Territory , Lugar de Trabajo/psicología , Estrés Laboral/epidemiología
15.
AJNR Am J Neuroradiol ; 45(4): 511-517, 2024 04 08.
Artículo en Inglés | MEDLINE | ID: mdl-38423746

RESUMEN

BACKGROUND AND PURPOSE: High-resolution CT is the mainstay for diagnosing an enlarged vestibular aqueduct (EVA), but MR imaging may be an appealing alternative, given its lack of ionizing radiation exposure. The purpose of this study was to determine how reliably MR imaging demonstrates the endolymphatic duct and endolymphatic duct enlargement in hearing-impaired children. MATERIALS AND METHODS: We performed a retrospective review of temporal bone high-resolution CT and MR imaging of hearing-impaired children evaluated between 2017 and 2020. Vestibular aqueduct diameter was measured on high-resolution CT. The vestibular aqueducts were categorized as being enlarged (EVA+) or nonenlarged (EVA-) using the Cincinnati criteria. The endolymphatic ducts were assessed on axial high-resolution CISS MR imaging. We categorized endolymphatic duct visibility into the following: type 1 (not visible), type 2 (faintly visible), and type 3 (easily visible). Mixed-effect logistic regression was used to identify associations between endolymphatic duct visibility and EVA. Interreader agreement for the endolymphatic duct among 3 independent readers was assessed using the Fleiss κ statistic. RESULTS: In 196 ears from 98 children, endolymphatic duct visibility on MR imaging was type 1 in 74.0%, type 2 in 14.8%, and type 3 in 11.2%; 20.4% of ears were EVA+ on high-resolution CT. There was a significant association between EVA+ status and endolymphatic duct visibility (P < .01). Endolymphatic duct visibility was type 1 in 87.1%, type 2 in 12.8%, and type 3 in 0% of EVA- ears and type 1 in 22.5%, type 2 in 22.5%, and type 3 in 55.0% of EVA+ ears. The predicted probability of a type 3 endolymphatic duct being EVA+ was 0.997. There was almost perfect agreement among the 3 readers for distinguishing type 3 from type 1 or 2 endolymphatic ducts. CONCLUSIONS: CISS MR imaging substantially underdiagnoses EVA; however, when a type 3 endolymphatic duct is evident, there is a >99% likelihood of an EVA.


Asunto(s)
Pérdida Auditiva Sensorineural , Acueducto Vestibular , Niño , Humanos , Conducto Endolinfático/diagnóstico por imagen , Acueducto Vestibular/diagnóstico por imagen , Imagen por Resonancia Magnética , Estudios Retrospectivos
16.
Curr Dev Nutr ; 8(5): 102156, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38737576

RESUMEN

Background: Older humans taking high concentrations of vitamin D3 supplementation for a prolonged time may be at risk of vitamin D toxicity. It is unclear how dietary super-doses (10,000 times greater than the requirement) can affect vitamin D3 status in aged animals. Aged laying hens could be a model to compare vitamin D3 supplementation effects with women in peri- or postmenopausal stages of life. Objectives: We investigated the dietary super-dose impacts of cholecalciferol (vitamin D3) on vitamin D3 status in aged laying hens in production. Methods: Forty-eight 68-wk-old Hy-Line Brown laying hens were individually housed in cages with 8 hens per dietary treatment for 11 wk. Hens were randomly assigned to 1 of 6 treatment groups of dietary vitamin D3 supplementation and consumed ad libitum. Supplementation concentrations were 400, 800, 7400, 14,000, 20,000, and 36,000 IU D3/kg of feed. At the end of the study, all hens were sacrificed, and tissue samples and feces were collected. Plasma and egg yolk vitamin D3 metabolites, calcium and phosphorus composition of eggshells, ileal digesta, and feces were measured. Duodenal, ileal, liver, and kidney gene expression levels were also measured. Results: We observed that increasing dietary vitamin D3 increased plasma vitamin D3 and egg yolk vitamin D3 (P < 0.0001 for both sites). We also observed an increase in plasma 24,25-dihydroxycholecalciferol as dietary vitamin D3 concentrations increased (P < 0.0001). The plasma 25-hydroxycholecalciferol:24,25-dihydroxycholecalciferol ratio exhibited an asymptotic relationship starting at the 14,000 IU/kg D3 treatment. Conclusions: Dietary super-doses of vitamin D3 led to greater plasma and egg yolk vitamin D3 concentrations, which shows that aged laying hens can deposit excess vitamin D3 in egg yolk. We suggest future research should explore how 24-hydroxylation mechanisms are affected by vitamin D3 supplementation. Further understanding of 24-hydroxylation can help ascertain ways to reduce the risk of vitamin D toxicity.

17.
Laryngoscope ; 134(5): 2401-2404, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38149671

RESUMEN

OBJECTIVE: To detail a modified surgical technique for implantation of the Osia 2 Bone Conduction Hearing Aid (BCHA) system and to assess intra- and postoperative outcomes of this technique. METHODS: A retrospective review was performed for cases undergoing implantation of an Osia 2 BCHA at a tertiary academic medical center. Modifications were made to the surgical procedure including: horizontal or curvilinear incisions, placement of the osseointegrated screw slightly superior to the plane of the external auditory canal, and double layer wound closure. Data regarding outcomes including demographics, incision type, surgical time, drilling requirements, and complications were collected using the electronic medical record. RESULTS: A total of twenty-eight cases were evaluated with 57.1% and 42.9% utilizing horizontal and curved incisions, respectively. The median age for recipients was 43.1 years with six pediatric cases included in the study. Median operative time was 58 min (43-126 min). The majority of cases required minimal (60.7%) or no drilling (28.6%) with a significant increase in operative time for those requiring moderate drilling versus minimal to no drilling (F = 8.02, p = 0.002). There were no intraoperative complications. One (3.6%) postoperative seroma occurred which resolved with conservative management. CONCLUSION: The proposed modified surgical technique is a safe and effective method for implantation of the transcutaneous BCHA system with a low complication rate. Keys include incision design, implant placement, and two-layered closure to minimize wound tension. These modifications can improve ease of the procedure and reduce operative time. These techniques also appear to be applicable to the pediatric population. LEVEL OF EVIDENCE: 3 Laryngoscope, 134:2401-2404, 2024.


Asunto(s)
Conducción Ósea , Audífonos , Humanos , Niño , Adulto , Implantación de Prótesis/métodos , Conducto Auditivo Externo/cirugía , Estudios Retrospectivos , Resultado del Tratamiento , Pérdida Auditiva Conductiva/cirugía , Pérdida Auditiva Conductiva/rehabilitación
18.
Laryngoscope ; 134(4): 1868-1873, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37767794

RESUMEN

OBJECTIVE: Determine variables that influence post-activation performance for cochlear implant (CI) recipients who lost low-frequency acoustic hearing. METHODS: A retrospective review evaluated CNC word recognition for adults with normal to moderately severe low-frequency hearing (preoperative unaided thresholds of ≤70 dB HL at 250 Hz) who were implanted between 2012 and 2021 at a tertiary academic center, lost functional acoustic hearing, and were fit with a CI-alone device. Performance scores were queried from the 1, 3, 6, 12, and 24-month post-activation visits. A linear mixed model evaluated the effects of age at implantation, array length (long vs. mid/short), and preoperative low-frequency hearing (normal to mild, moderate, and moderately severe) on speech recognition with a CI alone. RESULTS: 113 patients met the inclusion criteria. There was a significant main effect of interval (p < 0.001), indicating improved word recognition post-activation despite loss of residual hearing. There were significant main effects of age (p = 0.029) and array length (p = 0.038), with no effect of preoperative low-frequency hearing (p = 0.171). There was a significant 2-way interaction between age and array length (p = 0.018), indicating that older adults with mid/short arrays performed more poorly than younger adults with long lateral wall arrays when functional acoustic hearing was lost. CONCLUSION: CI recipients with preoperative functional low-frequency hearing experience a significant improvement in speech recognition with a CI alone as compared to preoperative performance-despite the loss of low-frequency hearing. Age and electrode array length may play a role in post-activation performance. These data have implications for the preoperative counseling and device selection for hearing preservation candidates. LEVEL OF EVIDENCE: 4 Laryngoscope, 134:1868-1873, 2024.


Asunto(s)
Implantación Coclear , Implantes Cocleares , Percepción del Habla , Humanos , Anciano , Percepción del Habla/fisiología , Audición , Pruebas Auditivas , Resultado del Tratamiento
19.
Laryngoscope ; 134(7): 3342-3348, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38345081

RESUMEN

OBJECTIVE: The study was conducted to evaluate the safety and efficacy of mild internal jugular (IJV) compression via an FDA approved compression collar for symptomatic treatment of venous pulsatile tinnitus. METHODS: This is a prospective study that recruited 20 adult patients with venous pulsatile tinnitus. Participants completed the Tinnitus Handicap Inventory (THI), were fitted with the collar, and rated symptom intensity on a 10-point tinnitus intensity scale before and during collar use. Once weekly for 4 weeks, they answered a survey quantifying days used, average tinnitus intensity before and after wearing the collar each day of use, and any safety concerns. Lastly, they completed an exit interview. The primary outcome was symptomatic relief, with secondary outcomes of safety, effect of treatment setting, effect of time, and quality of life assessed via nonparametric testing. RESULTS: 18 participants completed the study, and 276 paired daily before use/during use intensity scores were submitted. The median symptom intensity without the collar was 6 (IQR 4, 7), whereas with the collar it was 3 (IQR 2, 5), for a median symptomatic relief of 50%. The collar had a significant effect in reducing symptom intensity (p < 0.0001) and burden of illness via the THI (p < 0.0001). There was no effect of setting, frequency, or time on symptomatic relief with the collar. There were no adverse safety events reported aside from minor discomfort upon initial application. CONCLUSIONS: Venous compression collars offer acute symptom relief for patients with venous pulsatile tinnitus. Further study is needed to assess safety and efficacy of longitudinal use. LEVEL OF EVIDENCE: 4 Laryngoscope, 134:3342-3348, 2024.


Asunto(s)
Venas Yugulares , Acúfeno , Humanos , Acúfeno/terapia , Acúfeno/etiología , Femenino , Masculino , Estudios Prospectivos , Persona de Mediana Edad , Resultado del Tratamiento , Adulto , Anciano , Calidad de Vida , Vendajes de Compresión
20.
Laryngoscope ; 134(9): 4101-4110, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38656740

RESUMEN

OBJECTIVES: Research samples that are representative of patient populations are needed to ensure the generalizability of study findings. The primary aim was to assess the efficacy of a study design and recruitment strategy in obtaining a participant sample that was representative of the broader cochlear implant (CI) patient population at the CI center. A secondary aim was to review whether the CI recipient population was representative of the state population. METHODS: Demographic variables were compared for a research participant sample (n = 79) and the CI patient population (n = 338). The participant sample was recruited from the CI patient population. The study design included visits that were at the same location and frequency as the recommended clinical follow-up intervals. The demographics for the combined group (participant sample and patient population) were then compared to the reported demographics for the population in North Carolina. RESULTS: There were no significant differences between the participant sample and patient population for biological sex, age at implantation, racial distribution, socioeconomic position, degree of urbanization, or drive time to the CI center (p ≥ 0.086). The combined CI recipient population was significantly different from the North Carolina population for the distributions of race, ethnicity, and degree of urbanization (p < 0.001). CONCLUSION: The study design and recruitment strategy allowed for recruitment of a participant sample that was representative of the CI patient population. Disparities in access to cochlear implantation persist, as supported by the significant differences in the combined CI recipient population and the population for our state. LEVEL OF EVIDENCE: 3 Laryngoscope, 134:4101-4110, 2024.


Asunto(s)
Implantes Cocleares , Selección de Paciente , Humanos , Masculino , Femenino , Implantes Cocleares/estadística & datos numéricos , Persona de Mediana Edad , Adulto , Anciano , Implantación Coclear/estadística & datos numéricos , North Carolina/epidemiología , Adolescente , Niño , Investigación Biomédica/estadística & datos numéricos , Adulto Joven , Preescolar , Demografía , Proyectos de Investigación , Anciano de 80 o más Años
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