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Epidemiology has been transformed by the advent of Bayesian phylodynamic models that allow researchers to infer the geographic history of pathogen dispersal over a set of discrete geographic areas [1, 2]. These models provide powerful tools for understanding the spatial dynamics of disease outbreaks, but contain many parameters that are inferred from minimal geographic information (i.e., the single area in which each pathogen was sampled). Consequently, inferences under these models are inherently sensitive to our prior assumptions about the model parameters. Here, we demonstrate that the default priors used in empirical phylodynamic studies make strong and biologically unrealistic assumptions about the underlying geographic process. We provide empirical evidence that these unrealistic priors strongly (and adversely) impact commonly reported aspects of epidemiological studies, including: 1) the relative rates of dispersal between areas; 2) the importance of dispersal routes for the spread of pathogens among areas; 3) the number of dispersal events between areas, and; 4) the ancestral area in which a given outbreak originated. We offer strategies to avoid these problems, and develop tools to help researchers specify more biologically reasonable prior models that will realize the full potential of phylodynamic methods to elucidate pathogen biology and, ultimately, inform surveillance and monitoring policies to mitigate the impacts of disease outbreaks.
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Surtos de Doenças , Filogenia , Teorema de BayesRESUMO
SUMMARY: Phylodynamic methods are central to studies of the geographic and demographic history of disease outbreaks. Inference under discrete-geographic phylodynamic models-which involve many parameters that must be inferred from minimal information-is inherently sensitive to our prior beliefs about the model parameters. We present an interactive utility, PrioriTree, to help researchers identify and accommodate prior sensitivity in discrete-geographic inferences. Specifically, PrioriTree provides a suite of functions to generate input files for-and summarize output from-BEAST analyses for performing robust Bayesian inference, data-cloning analyses and assessing the relative and absolute fit of candidate discrete-geographic (prior) models to empirical datasets. AVAILABILITY AND IMPLEMENTATION: PrioriTree is distributed as an R package available at https://github.com/jsigao/prioritree, with a comprehensive user manual provided at https://bookdown.org/jsigao/prioritree_manual/.
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Surtos de Doenças , Software , Teorema de BayesRESUMO
SIGNIFICANCE: It is important to know whether early-onset vision loss and late-onset vision loss are associated with differences in the estimation of distances of sound sources within the environment. People with vision loss rely heavily on auditory cues for path planning, safe navigation, avoiding collisions, and activities of daily living. PURPOSE: Loss of vision can lead to substantial changes in auditory abilities. It is unclear whether differences in sound distance estimation exist in people with early-onset partial vision loss, late-onset partial vision loss, and normal vision. We investigated distance estimates for a range of sound sources and auditory environments in groups of participants with early- or late-onset partial visual loss and sighted controls. METHODS: Fifty-two participants heard static sounds with virtual distances ranging from 1.2 to 13.8 m within a simulated room. The room simulated either anechoic (no echoes) or reverberant environments. Stimuli were speech, music, or noise. Single sounds were presented, and participants reported the estimated distance of the sound source. Each participant took part in 480 trials. RESULTS: Analysis of variance showed significant main effects of visual status (p<0.05) environment (reverberant vs. anechoic, p<0.05) and also of the stimulus (p<0.05). Significant differences (p<0.05) were shown in the estimation of distances of sound sources between early-onset visually impaired participants and sighted controls for closer distances for all conditions except the anechoic speech condition and at middle distances for all conditions except the reverberant speech and music conditions. Late-onset visually impaired participants and sighted controls showed similar performance (p>0.05). CONCLUSIONS: The findings suggest that early-onset partial vision loss results in significant changes in judged auditory distance in different environments, especially for close and middle distances. Late-onset partial visual loss has less of an impact on the ability to estimate the distance of sound sources. The findings are consistent with a theoretical framework, the perceptual restructuring hypothesis, which was recently proposed to account for the effects of vision loss on audition.
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Localização de Som , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Adulto , Localização de Som/fisiologia , Julgamento , Percepção Auditiva/fisiologia , Percepção de Distância/fisiologia , Estimulação Acústica/métodos , Adulto Jovem , Acuidade Visual/fisiologia , Idade de Início , Idoso de 80 Anos ou mais , Sinais (Psicologia)RESUMO
OBJECTIVE: To develop an improved version of the profile of aided loudness (PAL), intended for assessment of the appropriateness of the loudness of everyday sounds. DESIGN: Initially, 16 participants with a range of ages and degrees of hearing loss indicated whether they encountered each situation described in the PAL and how specific they considered the description to be. Based on the responses, most situations from the PAL were eliminated and new situations were introduced, giving the Cambridge Aided Loudness Profile (CALP). The CALP was administered to 80 young and 22 older participants with normal hearing, who rated the loudness of each situation and satisfaction with this loudness (as for the original PAL). Satisfaction was strongly negatively correlated with loudness, suggesting that satisfaction was largely based on loudness. The CALP was then administered to 32 new young normal-hearing participants and 49 older participants with hearing loss, most of whom used hearing aids, who rated loudness and the appropriateness of loudness. RESULTS: Some situations were rated as loud but appropriate in loudness, indicating that the CALP can distinguish these aspects. CONCLUSIONS: The CALP questions were understood by all participants. The CALP may be useful for assessing the appropriateness of loudness.
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Importance: Since 2015, US government and related personnel have reported dizziness, pain, visual problems, and cognitive dysfunction after experiencing intrusive sounds and head pressure. The US government has labeled these anomalous health incidents (AHIs). Objective: To assess whether participants with AHIs differ significantly from US government control participants with respect to clinical, research, and biomarker assessments. Design, Setting, and Participants: Exploratory study conducted between June 2018 and July 2022 at the National Institutes of Health Clinical Center, involving 86 US government staff and family members with AHIs from Cuba, Austria, China, and other locations as well as 30 US government control participants. Exposures: AHIs. Main Outcomes and Measures: Participants were assessed with extensive clinical, auditory, vestibular, balance, visual, neuropsychological, and blood biomarkers (glial fibrillary acidic protein and neurofilament light) testing. The patients were analyzed based on the risk characteristics of the AHI identifying concerning cases as well as geographic location. Results: Eighty-six participants with AHIs (42 women and 44 men; mean [SD] age, 42.1 [9.1] years) and 30 vocationally matched government control participants (11 women and 19 men; mean [SD] age, 43.8 [10.1] years) were included in the analyses. Participants with AHIs were evaluated a median of 76 days (IQR, 30-537) from the most recent incident. In general, there were no significant differences between participants with AHIs and control participants in most tests of auditory, vestibular, cognitive, or visual function as well as levels of the blood biomarkers. Participants with AHIs had significantly increased fatigue, depression, posttraumatic stress, imbalance, and neurobehavioral symptoms compared with the control participants. There were no differences in these findings based on the risk characteristics of the incident or geographic location of the AHIs. Twenty-four patients (28%) with AHI presented with functional neurological disorders. Conclusions and Relevance: In this exploratory study, there were no significant differences between individuals reporting AHIs and matched control participants with respect to most clinical, research, and biomarker measures, except for objective and self-reported measures of imbalance and symptoms of fatigue, posttraumatic stress, and depression. This study did not replicate the findings of previous studies, although differences in the populations included and the timing of assessments limit direct comparisons.
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Família , Governo , Masculino , Humanos , Feminino , Adulto , Biomarcadores , Fadiga , Medidas de SegurançaRESUMO
Importance: US government personnel stationed internationally have reported anomalous health incidents (AHIs), with some individuals experiencing persistent debilitating symptoms. Objective: To assess the potential presence of magnetic resonance imaging (MRI)-detectable brain lesions in participants with AHIs, with respect to a well-matched control group. Design, Setting, and Participants: This exploratory study was conducted at the National Institutes of Health (NIH) Clinical Center and the NIH MRI Research Facility between June 2018 and November 2022. Eighty-one participants with AHIs and 48 age- and sex-matched control participants, 29 of whom had similar employment as the AHI group, were assessed with clinical, volumetric, and functional MRI. A high-quality diffusion MRI scan and a second volumetric scan were also acquired during a different session. The structural MRI acquisition protocol was optimized to achieve high reproducibility. Forty-nine participants with AHIs had at least 1 additional imaging session approximately 6 to 12 months from the first visit. Exposure: AHIs. Main Outcomes and Measures: Group-level quantitative metrics obtained from multiple modalities: (1) volumetric measurement, voxel-wise and region of interest (ROI)-wise; (2) diffusion MRI-derived metrics, voxel-wise and ROI-wise; and (3) ROI-wise within-network resting-state functional connectivity using functional MRI. Exploratory data analyses used both standard, nonparametric tests and bayesian multilevel modeling. Results: Among the 81 participants with AHIs, the mean (SD) age was 42 (9) years and 49% were female; among the 48 control participants, the mean (SD) age was 43 (11) years and 42% were female. Imaging scans were performed as early as 14 days after experiencing AHIs with a median delay period of 80 (IQR, 36-544) days. After adjustment for multiple comparisons, no significant differences between participants with AHIs and control participants were found for any MRI modality. At an unadjusted threshold (P < .05), compared with control participants, participants with AHIs had lower intranetwork connectivity in the salience networks, a larger corpus callosum, and diffusion MRI differences in the corpus callosum, superior longitudinal fasciculus, cingulum, inferior cerebellar peduncle, and amygdala. The structural MRI measurements were highly reproducible (median coefficient of variation <1% across all global volumetric ROIs and <1.5% for all white matter ROIs for diffusion metrics). Even individuals with large differences from control participants exhibited stable longitudinal results (typically, <±1% across visits), suggesting the absence of evolving lesions. The relationships between the imaging and clinical variables were weak (median Spearman ρ = 0.10). The study did not replicate the results of a previously published investigation of AHIs. Conclusions and Relevance: In this exploratory neuroimaging study, there were no significant differences in imaging measures of brain structure or function between individuals reporting AHIs and matched control participants after adjustment for multiple comparisons.
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Imagem de Tensor de Difusão , Substância Branca , Humanos , Feminino , Adulto , Masculino , Imagem de Tensor de Difusão/métodos , Reprodutibilidade dos Testes , Teorema de Bayes , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Imageamento por Ressonância Magnética/métodos , Neuroimagem , Substância Branca/patologia , Família , Governo , Medidas de SegurançaRESUMO
BACKGROUND: We examined spatial patterns of brain atrophy after mild, moderate, and severe traumatic brain injury (TBI), the relationship between progression of brain atrophy with initial traumatic axonal injury (TAI), cognitive outcome, and with serum biomarkers of brain injury. METHODS: A total of 143 patients with TBI and 43 controls were studied cross-sectionally and longitudinally up to 5 years with multiple assessments, which included brain magnetic resonance imaging, cognitive testing, and serum biomarkers. RESULTS: TBI patients showed progressive volume loss regardless of injury severity over several years, and TAI was independently associated with accelerated brain atrophy. Cognitive performance improved over time. Higher baseline serum neurofilament light (NfL) and glial fibrillary acidic protein (GFAP) were associated with greater rate of brain atrophy over 5 years. DISCUSSSION: Spatial patterns of atrophy differ by injury severity and TAI is associated with the progression of brain atrophy. Serum NfL and GFAP show promise as non-invasive prognostic biomarkers of progressive neurodegeneration in TBI. HIGHLIGHTS: In this longitudinal study of patient with mild, moderate, and severe traumatic brain injury (TBI) who were assessed with paired magnetic resonance imaging (MRI), blood biomarkers, and cognitive assessments, we found that brain atrophy after TBI is progressive and continues for many years even after a mild head trauma without signs of brain injury on conventional MRI. We found that spatial pattern of brain atrophy differs between mild, moderate, and severe TBI, where in patients with mild TBI , atrophy is mainly seen in the gray matter, while in those with moderate to severe brain injury atrophy is predominantly seen in the subcortical gray matter and whiter matter. Cognitive performance improves over time after a TBI. Serum measures of neurofilament light or glial fibrillary acidic protein are associated with progression of brain atrophy after TBI.
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Atrofia , Biomarcadores , Lesões Encefálicas Traumáticas , Progressão da Doença , Proteína Glial Fibrilar Ácida , Imageamento por Ressonância Magnética , Proteínas de Neurofilamentos , Humanos , Proteína Glial Fibrilar Ácida/sangue , Masculino , Proteínas de Neurofilamentos/sangue , Feminino , Lesões Encefálicas Traumáticas/sangue , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/diagnóstico por imagem , Lesões Encefálicas Traumáticas/patologia , Biomarcadores/sangue , Estudos Longitudinais , Atrofia/patologia , Pessoa de Meia-Idade , Adulto , Estudos Transversais , Encéfalo/patologia , Encéfalo/diagnóstico por imagem , Testes Neuropsicológicos/estatística & dados numéricosRESUMO
Phylodynamic methods reveal the spatial and temporal dynamics of viral geographic spread, and have featured prominently in studies of the COVID-19 pandemic. Virtually all such studies are based on phylodynamic models that assume-despite direct and compelling evidence to the contrary-that rates of viral geographic dispersal are constant through time. Here, we: (1) extend phylodynamic models to allow both the average and relative rates of viral dispersal to vary independently between pre-specified time intervals; (2) implement methods to infer the number and timing of viral dispersal events between areas; and (3) develop statistics to assess the absolute fit of discrete-geographic phylodynamic models to empirical datasets. We first validate our new methods using simulations, and then apply them to a SARS-CoV-2 dataset from the early phase of the COVID-19 pandemic. We show that: (1) under simulation, failure to accommodate interval-specific variation in the study data will severely bias parameter estimates; (2) in practice, our interval-specific discrete-geographic phylodynamic models can significantly improve the relative and absolute fit to empirical data; and (3) the increased realism of our interval-specific models provides qualitatively different inferences regarding key aspects of the COVID-19 pandemic-revealing significant temporal variation in global viral dispersal rates, viral dispersal routes, and the number of viral dispersal events between areas-and alters interpretations regarding the efficacy of intervention measures to mitigate the pandemic.
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COVID-19 , Pandemias , COVID-19/epidemiologia , Humanos , Filogenia , Filogeografia , SARS-CoV-2/genéticaRESUMO
BACKGROUND AND OBJECTIVES: Military service members experience occupational-specific injuries that may result in chronic pain and comorbid behavioral health concerns. METHODS: Data from the Defense Medical Epidemiology Database was used to examine opioid use disorder (OUD) diagnoses between 2016 and 2021. Statistical analysis calculated incidence rates and diagnostic variability by demographic density. RESULTS: The average incidence rate of OUD was 6.1 (per 10,000) and declined by 34% between 2016 and 2021. Diagnoses were most frequently made in service members classified as male, married, white, aged 30-39, junior enlisted, and serving in the Army. CONCLUSIONS AND SCIENTIFIC SIGNIFICANCE: To our knowledge, this is the first study to examine the incidence rates of OUD among active duty personnel.
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Militares , Humanos , Masculino , Estados Unidos , Incidência , Fatores de RiscoRESUMO
OBJECTIVE: To describe headache characteristics over time in patients with traumatic brain injury (TBI). SETTING: Patients enrolled and followed at the National Institutes of Health Clinical Center between 2011 and 2020. PARTICIPANTS: There were 147 patients with TBI, with 74 mild TBI (mTBI), 49 moderate (modTBI), 24 severe (sTBI), and 20 individuals without brain injury (IWBIs). DESIGN: Regular surveys of headache characteristics in patients with TBI were conducted. Patients were enrolled as early as 30 days post-injury and followed up to 5 years, for 419 total visits and 80 patients with multiple return visits. MAIN MEASURES: Surveys of headache characteristics, including headache severity, were measured on a 0- to 10-point Likert scale and headache frequency quantified as headaches per month. Patients with migraine-type headaches ( n = 39) were identified by a clinician-administered tool. Functional outcomes were measured using the Glasgow Outcome Scale-Extended (GOS-E) and quality of life by the Satisfaction with Life Scale (SWLS) and the 36-item Short Form Survey (SF-36). RESULTS: At their initial visit, patients with TBI had more severe and frequent headaches than IWBIs (median 5 vs 2.5, P < .001; median 2 vs 0.2, P < .001), as did patients with mTBI compared with modTBI/sTBI (all P ≤ .01). Migraines were associated with lower SWLS and SF-36 scores. Migraines and young age were associated with higher headache severity and frequency across time points. Longitudinally, time post-injury correlated with improvement in headache severity and frequency without differences by injury severity. However, time post-injury did not correlate with improvement in headache characteristics in a patient subgroup with moderate/severe headaches. CONCLUSION: Our findings suggest that patients with mild, moderate, or severe TBI see improvement in headaches over time. However, patients should be counseled that improvement is modest and seen more in patients with milder headache symptoms. Patients with migraine headaches in particular are at risk for worse headache characteristics with greater impact on quality of life.
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Lesões Encefálicas Traumáticas , Lesões Encefálicas , Transtornos de Enxaqueca , Humanos , Qualidade de Vida , Cefaleia/epidemiologia , Cefaleia/etiologia , Transtornos de Enxaqueca/diagnóstico , Transtornos de Enxaqueca/epidemiologia , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/diagnóstico , Lesões Encefálicas/diagnósticoRESUMO
Transcriptomes are key to understanding the relationship between genotype and phenotype. The ability to infer the expression state (active or inactive) of genes in the transcriptome offers unique benefits for addressing this issue. For example, qualitative changes in gene expression may underly the origin of novel phenotypes, and expression states are readily comparable between tissues and species. However, inferring the expression state of genes is a surprisingly difficult problem, owing to the complex biological and technical processes that give rise to observed transcriptomic datasets. Here, we develop a hierarchical Bayesian mixture model that describes this complex process and allows us to infer expression state of genes from replicate transcriptomic libraries. We explore the statistical behavior of this method with analyses of simulated datasets-where we demonstrate its ability to correctly infer true (known) expression states-and empirical-benchmark datasets, where we demonstrate that the expression states inferred from RNA-sequencing (RNA-seq) datasets using our method are consistent with those based on independent evidence. The power of our method to correctly infer expression states is generally high and remarkably, approaches the maximum possible power for this inference problem. We present an empirical analysis of primate-brain transcriptomes, which identifies genes that have a unique expression state in humans. Our method is implemented in the freely available R package zigzag.
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Primatas/genética , Animais , Teorema de Bayes , Perfilação da Expressão Gênica/métodos , Humanos , Primatas/metabolismo , Análise de Sequência de RNA , TranscriptomaRESUMO
The envelope regularity discrimination (ERD) test assesses the ability to discriminate irregular from regular amplitude modulation (AM). The measured threshold is called the irregularity index (II). It was hypothesized that the II at threshold should be almost unaffected by the loudness recruitment that is associated with cochlear hearing loss because the effect of recruitment is similar to multiplying the AM depth by a certain factor, and II values depend on the amount of envelope irregularity relative to the baseline modulation depth. To test this hypothesis, the ERD test was administered to 60 older adults with varying degrees of hearing loss, using carrier frequencies of 1 and 4 kHz. The II values for the two carrier frequencies were highly correlated, indicating that the ERD test was measuring a consistent characteristic of each subject. The II values at 1 and 4 kHz were not significantly correlated with the audiometric thresholds at the corresponding frequencies, consistent with the hypothesis. The II values at 4 kHz were significantly positively correlated with age. There was an unexpected negative correlation between II values and a measure of noise exposure. This is argued to reflect the confounding effects of listening skills.
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Surdez , Perda Auditiva Neurossensorial , Perda Auditiva , Humanos , Idoso , Ruído/efeitos adversos , Limiar AuditivoRESUMO
Psychoacoustic and speech perception measures were compared for a group who were exposed to noise regularly through listening to music via personal music players (PMP) and a control group without such exposure. Lifetime noise exposure, quantified using the NESI questionnaire, averaged ten times higher for the exposed group than for the control group. Audiometric thresholds were similar for the two groups over the conventional frequency range up to 8 kHz, but for higher frequencies, the exposed group had higher thresholds than the control group. Amplitude modulation detection (AMD) thresholds were measured using a 4000-Hz sinusoidal carrier presented in threshold-equalizing noise at 30, 60, and 90 dB sound pressure level (SPL) for modulation frequencies of 8, 16, 32, and 64 Hz. At 90 dB SPL but not at the lower levels, AMD thresholds were significantly higher (worse) for the exposed than for the control group, especially for low modulation frequencies. The exposed group required significantly higher signal-to-noise ratios than the control group to understand sentences in noise. Otoacoustic emissions did not differ for the two groups. It is concluded that listening to music via PMP can have subtle deleterious effects on speech perception, AM detection, and hearing sensitivity over the extended high-frequency range.
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Percepção da Fala , Fala , Limiar Auditivo , Audição , Ruído/efeitos adversos , Percepção AuditivaRESUMO
OBJECTIVE: To evaluate differences in tinnitus impact, hyperacusis and hearing threshold level (HTL) between patients with unilateral and bilateral tinnitus. For patients with unilateral tinnitus, to compare audiological variables for the tinnitus ear and the non-tinnitus ear. To assess whether the presence of unilateral tinnitus increases the likelihood of interaural hearing asymmetry (relative to bilateral tinnitus) that warrants referral for an MRI scan. DESIGN: Retrospective cross-sectional. STUDY SAMPLE: Data regarding HTLs and responses to self-report questionnaires were collected from the records of 311 patients attending a tinnitus clinic. RESULTS: 38.5% had unilateral tinnitus and the ears with tinnitus had higher HTLs and greater HTL slopes than the ears without tinnitus. There was no significant difference in tinnitus impact and hyperacusis between patients with unilateral and bilateral tinnitus. 40% of patients with unilateral tinnitus and 13% of patients with bilateral tinnitus had a between-ear difference in HTL ≥15 dB at two adjacent frequencies (2AF15 asymmetry). Unilateral tinnitus increased the risk of 2AF15 asymmetry by a factor of 4.4. CONCLUSIONS: Unilateral tinnitus increases the risk of having interaural asymmetry in HTLs that warrants referral for an MRI scan.
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OBJECTIVE: To evaluate the psychometric properties of the Tinnitus Impact Questionnaire (TIQ), whose questions focus on assessing the impact of tinnitus on the patient's day to day activities, mood, and sleep, and not on hearing difficulties. DESIGN: This was a retrospective cross-sectional study. STUDY SAMPLE: Data were included for 172 adult patients who attended a tinnitus and hyperacusis clinic in the UK within a six-month period and who had completed the TIQ. RESULTS: Two items whose scores were very highly correlated with those for other items were removed, leaving seven items. Exploratory factor analysis suggested a single factor for the TIQ. A multiple causes multiple indicator model showed significant but very small direct effects of age on TIQ scores for two items, after adjustment for gender. The TIQ had excellent internal consistency, with Cronbach's alpha = 0.89. The total TIQ score was moderately to strongly correlated with scores for the Tinnitus Handicap Inventory, Screening for Anxiety and Depression-Tinnitus questionnaire, Hyperacusis Questionnaire, and Hyperacusis Impact Questionnaire, indicating convergent validity. The TIQ score was weakly correlated with the pure-tone average hearing threshold, indicating discriminant validity. CONCLUSIONS: The TIQ is a brief, valid and internally consistent questionnaire for assessing the impact of tinnitus.
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Zumbido , Adulto , Humanos , Zumbido/diagnóstico , Hiperacusia/diagnóstico , Psicometria , Estudos Transversais , Estudos Retrospectivos , Inquéritos e QuestionáriosRESUMO
OBJECTIVE: To examine whether the responsiveness of young children to simple sounds was associated with entertainment screen time (EST), opportunities for social interaction, and social and communication skills. DESIGN: Parents completed a questionnaire covering, for years one and two, the number of times the child met with other children; the number of words the child spoke; and the daily amount of EST. Social, attention and communication skills were assessed. STUDY SAMPLE: Participants were 118 children, aged 15 to 46 months. They were initially assessed behaviourally using simple sounds. Children who responded to such sounds were denoted the Responsive group. Children who did not were assessed using familiar songs and denoted the Unresponsive group. RESULTS: The two groups did not differ significantly in mean age or the number of opportunities to meet other children. The Unresponsive group had significantly fewer words than the Responsive group at 12 and 24 months and had significantly higher EST than the Responsive group for years 1 and 2. The Unresponsive group showed lower social, attention and communication skills than the Responsive group. CONCLUSIONS: High EST was associated with poorer auditory and social skills. Hence, it may be wise to limit the EST of young children.
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Visual spatial information plays an important role in calibrating auditory space. Blindness results in deficits in a number of auditory abilities, which have been explained in terms of the hypothesis that visual information is needed to calibrate audition. When judging the size of a novel room when only auditory cues are available, normally sighted participants may use the location of the farthest sound source to infer the nearest possible distance of the far wall. However, for people with partial visual loss (distinct from blindness in that some vision is present), such a strategy may not be reliable if vision is needed to calibrate auditory cues for distance. In the current study, participants were presented with sounds at different distances (ranging from 1.2 to 13.8 m) in a simulated reverberant (T60 = 700 ms) or anechoic room. Farthest distance judgments and room size judgments (volume and area) were obtained from blindfolded participants (18 normally sighted, 38 partially sighted) for speech, music, and noise stimuli. With sighted participants, the judged room volume and farthest sound source distance estimates were positively correlated (p < 0.05) for all conditions. Participants with visual losses showed no significant correlations for any of the conditions tested. A similar pattern of results was observed for the correlations between farthest distance and room floor area estimates. Results demonstrate that partial visual loss disrupts the relationship between judged room size and sound source distance that is shown by sighted participants.
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Cegueira , Localização de Som , Estimulação Acústica , Percepção Auditiva , Sinais (Psicologia) , Humanos , SomRESUMO
Although pediatric airway and respiratory emergencies represent high-acuity situations, the ability of EMS clinicians to effectively manage these patients is hampered by infrequent clinical exposure and shortcomings in pediatric-specific education. Cognitive gaps in EMS clinicians' understanding of the differences between pediatric and adult airway anatomy and respiratory physiology and pathology, variability in the training provided to EMS clinicians, and decay of the psychomotor skills necessary to safely and effectively manage pediatric patients experiencing respiratory emergencies collectively pose significant threats to the quality and safety of care delivered to pediatric patients. NAEMSP recommends:Pediatric airway education should include discussion of the factors that make pediatric airway management challenging.EMS agencies should provide pediatric-specific education that addresses recognition and treatment of pediatric respiratory distress based upon pathophysiology affecting upper airways, lower airways, cardiovascular systems, or extrinsic causes of disordered breathing. Pediatric airway training should also differentiate between hypoxic and hypercapnic respiratory failure. Education should emphasize that the cognitive and psychomotor skills requisite in management of pediatric respiratory emergencies will differ across patient age groups.EMS clinicians should be provided education and training in technology-dependent children and children and youth with special health care needs.EMS clinicians should receive initial and ongoing education and training in pediatric airway and respiratory conditions that emphasizes the principle of using the least invasive most effective strategies to achieve oxygenation and ventilation.Initial and continuing pediatric-focused education should be structured to maintain EMS clinician competency in the assessment and management of pediatric airway and respiratory emergencies and should be provided on a recurring basis to mitigate the decay of EMS clinicians' knowledge and skills that occurs due to infrequent field-based clinical exposure.Integration of clinician education programs with quality management programs is essential for the development and delivery of initial and continuing education intended to help EMS clinicians attain and maintain proficiency in pediatric airway and respiratory management.
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Serviços Médicos de Emergência , Síndrome do Desconforto Respiratório , Insuficiência Respiratória , Adolescente , Adulto , Manuseio das Vias Aéreas , Criança , Emergências , Humanos , Insuficiência Respiratória/terapiaRESUMO
The unique challenges of pediatric respiratory and airway emergencies require the development and maintenance of a prehospital quality management program that includes pediatric-focused medical oversight and clinical care expertise, data collection, operational considerations, focused education, and clinician competency evaluation.NAEMSP recommends:Medical director oversight must include a focus on pediatric airway and respiratory management and integrate pediatric-specific elements in guideline development, competency assessment, and skills maintenance efforts.EMS agencies are encouraged to collaborate with medical professionals who have expertise in pediatric emergency care to provide support for quality management initiatives in pediatric respiratory distress and airway management.EMS agencies should define quality indicators for pediatric-specific elements in respiratory distress and airway management and benchmark performance based on regional and national standards.EMS agencies should implement both quantitative (objective) and qualitative (subjective) measures of performance to assess competency in pediatric respiratory distress and airway management.EMS agencies choosing to incorporate pediatric endotracheal intubation or supraglottic airway insertion must use pediatric-specific quality management benchmarks and perform focused review of advanced airway management.
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Serviços Médicos de Emergência , Síndrome do Desconforto Respiratório , Manuseio das Vias Aéreas , Benchmarking , Criança , Humanos , Intubação IntratraquealRESUMO
Devices and techniques such as bag-valve-mask ventilation, endotracheal intubation, supraglottic airway devices, and noninvasive ventilation offer important tools for airway management in critically ill EMS patients. Over the past decade the tools, technology, and strategies used to assess and manage pediatric respiratory and airway emergencies have evolved, and evidence regarding their use continues to grow.NAEMSP recommends:Methods and tools used to properly size pediatric equipment for ages ranging from newborns to adolescents should be available to all EMS clinicians. All pediatric equipment should be routinely checked and clearly identifiable in EMS equipment supply bags and vehicles.EMS agencies should train and equip their clinicians with age-appropriate pulse oximetry and capnography equipment to aid in the assessment and management of pediatric respiratory distress and airway emergencies.EMS agencies should emphasize noninvasive positive pressure ventilation and effective bag-valve-mask ventilation strategies in children.Supraglottic airways can be used as primary or secondary airway management interventions for pediatric respiratory failure and cardiac arrest in the EMS setting.Pediatric endotracheal intubation has unclear benefit in the EMS setting. Advanced approaches to pediatric ETI including drug-assisted airway management, apneic oxygenation, and use of direct and video laryngoscopy require further research to more clearly define their risks and benefits prior to widespread implementation.If considering the use of pediatric endotracheal intubation, the EMS medical director must ensure the program provides pediatric-specific initial training and ongoing competency and quality management activities to ensure that EMS clinicians attain and maintain mastery of the intervention.Paramedic use of direct laryngoscopy paired with Magill forceps to facilitate foreign body removal in the pediatric patient should be maintained even when pediatric endotracheal intubation is not approved as a local clinical intervention.