Aerospace medicine and biology: A continuing bibliography with indexes (supplement 299)

This bibliography lists 96 reports, articles, and other documents introduced into the NASA scientific and technical information system in June, 1987

Vocal tract dimensions and vocal fold vibratory characteristics of professional singers of different singing voice types

This study aimed to examine the relationship between different singing voice types and their vocal fold vibratory characteristics and vocal tract dimensions. A total of 19 tenors, 10 baritones, 29 sopranos, and 4 mezzo-sopranos participated in the study. Electroglottography (EGG) was used to measure the vocal fold vibratory characteristics, based on which parameters including open quotient (Oq) and fundamental frequency (F0) were derived. During the experiment, the participants sang the song “Happy Birthday” with constant loudness level and at the most comfortable pitch level. A pharyngometer was used to measure singers’ vocal tract dimensions. Results showed that tenors had significantly higher Oq/F0 gradient than baritones in chest and head registers, while sopranos had generally higher Oq/F0 gradient than mezzo-sopranos in chest and head registers. Regarding vocal tract dimensions, sopranos generally exhibited greater vocal tract length and volume values than mezzo-sopranos. The present study provides insights to applying both vocal fold vibratory characteristics and vocal tract dimensions in voice classification for male and female singers.published_or_final_versionSpeech and Hearing SciencesBachelorBachelor of Science in Speech and Hearing Science

Snoring in Portuguese primary school children

OBJECTIVE: To determine the prevalence of snoring and its potential associations with sleep problems, such as daytime symptoms, medical conditions, school performance, and behavioral disturbances in Portuguese children attending primary school. METHODS: A previously validated questionnaire was sent to the parents of 1381 children attending primary schools in a parish of Coimbra, Portugal. To assess behavioral disturbances, the Portuguese version of Rutter's Children's Behavior Questionnaire for completion by teachers was used. RESULTS: Of the 988 questionnaires returned (71.5%), complete information concerning snoring was obtained for 976 children (496 girls and 480 boys; mean age: 8.1 +/- 1.5 years). Loud snoring during sleep was reported as frequent or constantly present (LSn) in 84 children (8.6%), as occasionally present in 299 children (30.6%), and as never present (NSn) by 593 children (60.8%). The LSn and NSn groups did not differ with respect to age, gender, sleep duration, time to fall asleep, frequency of night wakings, bedwetting, daytime tiredness, and school achievement. However, LSn was significantly associated with increased bedtime problems (fears and struggles), increased need for comforting activities to fall asleep, behaviors suggestive of parasomnias (sleep talking, teeth grinding, and night terrors), increased daytime sleepiness and irritability, and behavioral disturbances. Children in the LSn group were also more likely to report recurrent medical problems particularly those involving infections of the respiratory tract. CONCLUSIONS: Snoring is a common symptom in Portuguese children that is associated with behavioral daytime and sleep time disturbances. Children with loud snoring may benefit from early evaluation and intervention

obstructive sleep apnea

The aim of this article is to provide a detailed description for obstructive sleep apnea regarding its signs and symptoms, the way it is diagnosed, the risk factors, management, the role of dentists and oral appliances in treatment. Obstructive sleep apnea (OSA) is a potentially life-threatening disorder characterized by repeated collapse of the upper airway during sleep, with periodic cessation of breathing for more than ten seconds. Dental professionals have a unique doctor patient relationship that can help them in recognizing the sleep disorder and co-managing the patients along with a physician or a sleep specialist. Oral appliance therapy is an important treatment modality for sleep apnea patient

Noninvasive Dynamic Characterization of Swallowing Kinematics and Impairments in High Resolution Cervical Auscultation via Deep Learning

Swallowing is a complex sensorimotor activity by which food and liquids are transferred from the oral cavity to the stomach. Swallowing requires the coordination between multiple subsystems which makes it subject to impairment secondary to a variety of medical or surgically related conditions. Dysphagia refers to any swallowing disorder and is common in patients with head and neck cancer and neurological conditions such as stroke. Dysphagia affects nearly 9 million adults and causes death for more than 60,000 yearly in the US. In this research, we utilize advanced signal processing techniques with sensor technology and deep learning methods to develop a noninvasive and widely available tool for the evaluation and diagnosis of swallowing problems. We investigate the use of modern spectral estimation methods in addition to convolutional recurrent neural networks to demarcate and localize the important swallowing physiological events that contribute to airway protection solely based on signals collected from non-invasive sensors attached to the anterior neck. These events include the full swallowing activity, upper esophageal sphincter opening duration and maximal opening diameter, and aspiration. We believe that combining sensor technology and state of the art deep learning architectures specialized in time series analysis, will help achieve great advances for dysphagia detection and management in terms of non-invasiveness, portability, and availability. Like never before, such advances will enable patients to get continuous feedback about their swallowing out of standard clinical care setting which will extremely facilitate their daily activities and enhance the quality of their lives

Submandibular mechanical stimulation of upper airway muscles to treat obstructive sleep apnea

The extrinsic tongue muscles are activated in coordination with pharyngeal muscles to keep a patent airway during respiration in wakefulness and sleep. The activity of genioglossus, the primary tongue-protruding muscle playing an important role in this coordination, is known to be modulated by several reflex pathways mediated through the mechanoreceptors of the upper airways. The main objective is to investigate the effectiveness of activating these reflex pathways with mechanical stimulations, for the long-term goal of improving the upper airway patency during disordered breathing in sleep. The genioglossus response is examined during mandibular and sub-mandibular mechanical stimulations in healthy subjects during wakefulness. The genioglossus activity is recorded with custom-made sublingual EMG electrode molded out of silicone. Mechanical vibrations are applied to the lower jaw at 8 and 12 Hz with an amplitude of 5 mm in the first experiment, and to the sub-mandibular area at three different intensities (0.2-0.9 mm, 21-33 Hz) in the second experiment. The effects of sub-mandibular mechanical vibrations are also investigated in severe obstructive sleep apnea patients during a whole night sleep study. The major findings of this study are that the genioglossus reflexively responds to the mechanical vibrations applied to the mandible and the sub-mandibular skin surface in healthy subjects during wakefulness and the sub-mandibular stimulations during sleep terminate the apnea earlier and decrease the level of hypoxia with smaller micro arousals

Charcot–Marie–Tooth disease: Genetics, epidemiology and complications

Background and aims: Charcot Marie Tooth disease (CMT) is the most prevalent hereditary neuropathy and its frequency is 1 in 2500. CMT is a heterogeneous disease and has different clinical symptoms. The prevalence of CMT and involved genes differ in different countries. CMT patients experience considerable sleep problems and a higher risk of decreased quality of life. In this work it was aimed to provide a review on the genetic and epidemiologic aspects of this disease. Methods: In the current review article, we performed a literature search on the epidemiology of Charcot–Marie–Tooth disease” and provided a brief review on epidemiology, genetic, and complications of CMT. Databases Web of Science and PubMed were searched using the Endnote software for the publications on CMT during 2000 to 2016. Results: Charcot Marie Tooth disease has different prevalence around the world and is the most common neuropathy. Epidemiological studies have estimated the prevalence of CMT in Japan 1/9200, in Iceland 1/8300, in Spain 1/3500 and in Italy 1/5700.The patients have different phenotype and the age of onset. There is a variety of inherited patterns of disease and many genes have been identified responsible whose mutations are main cause of the disease. Conclusion: Due to the impact of this kind of disabilities on the national health, further studies seem to be necessary to gain better knowledge of the disease particularly in the regions with higher prevalence. Moreover molecular biology services offered by genetic laboratories can reduce the incidence of disorder

The effect of therapy on arousal from sleep in patients with respiratory sleep disorders

Vibrotactile positional therapy (PT) is a relatively new treatment for positional obstructive sleep apnoea (POSA). It uses vibrotactile stimulus to encourage the sleeper to change position when supine. The overall aim of this thesis was to investigate the efficacy of vibrotactile PT as a clinical treatment for patients with POSA. To achieve this, different experimental approaches were used, including a systematic review and meta-analysis, a clinical trial, and a physiological study. The systematic review was carried out to evaluate the effect of vibrotactile PT on apnoea hypopnoea index (AHI), percentage of time spent in supine (%Tsupine), and patient-centred outcomes in patients with POSA compared to baseline. The results showed that vibrotactile PT was effective in reducing both AHI and %Tsupine. Although the Epworth Sleepiness Scale and the Functional Outcomes of Sleep Questionnaire minimally improved, these changes did not reach clinically important differences; however, limited data were found on quality of life (SF-36) vitality score. A prospective, three-month, multicentre, randomised, parallel, double-blind trial (The POSA Trial, ISRCTN51740863) was developed to investigate the effect of vibrotactile PT on AHI, quality of life and daytime functioning at follow-up, adjusted for the baseline, in patients with POSA compared to sham-vibrotactile PT. Baseline data (AHI, quality of life and daytime functioning) obtained from the participants recruited at the Royal Brompton Hospital are presented in the thesis. The mean baseline AHI for RBH participants was in the mild OSA category compared to the patients in the systematic review; however, a higher baseline %Tsupine was found. The baseline patient-centred outcomes were also comparable to those found in the systematic review. A physiological study in healthy participants (n=27) was carried out to investigate the effect of vibrotactile stimulus on arousability from sleep. A novel analysis method was developed to measure arousability. This included the duration from the vibrotactile stimulus to the position change using polysomnography. The results of this study showed heterogenous arousability responses to the vibrotactile stimulus with different phenotypes. Compared to males, healthy females took longer to respond to the vibrotactile stimulus and, therefore, were more resilient to arousability. In summary, the findings of this thesis have shown that vibrotactile PT devices are effective in treating patients with POSA. However, limited data on sensitive patient-centred outcomes exist. The POSA trial will provide data to address this evidence gap. Furthermore, the physiological findings in people without OSA showed that males are more arousable than females. This information may be of value when considering personalisation of clinical treatment. Future research of POSA will need to consider the arousability phenotype when planning treatment options.Open Acces

Chronic cough—the limitation and advances in assessment techniques

Accurate and consistent assessments of cough are essential to advance the understanding of the mechanisms of cough and individualised the management of patients. Considerable progress has been made in this work. Here we reviewed the currently available tools for subjectively and objectively measuring both cough sensitivity and severity. We also provided some opinions on the new techniques and future directions. The simple and practical Visual Analogue Scale (VAS), the Leicester Cough Questionnaire (LCQ), and the Cough Specific Quality of Life Questionnaire (CQLQ) are the most widely used self-reported questionnaires for evaluating and quantifying cough severity. The Hull Airway Reflux Questionnaire (HARQ) is a tool to elucidate the constellation of symptoms underlying the diagnosis of chronic cough. Chemical excitation tests are widely used to explore the pathophysiological mechanisms of the cough reflex, such as capsaicin, citric acid and adenosine triphosphate (ATP) challenge test. Cough frequency is an ideal primary endpoint for clinical research, but the application of cough counters has been limited in clinical practice by the high cost and reliance on aural validation. The ongoing development of cough detection technology for smartphone apps and wearable devices will hopefully simplify cough counting, thus transitioning it from niche research to a widely available clinical application

An exploration of swallowing stimulation in the infant

The purpose of this study was twofold: to determine the effects of two types of non-invasive, peripheral sensory stimulation on the frequency of infant swallowing and to explore the cortical activation patterns in response to stimulation in the somatosensory and motor regions of the brain during infancy, between 2-4 months and 7-9 months of age. The two different forms of mechanical stimulation investigated include pacifier stimulation to the lips and oral cavity and vibrotactile stimulation via the external throat area to the laryngeal tissues. The study represents a prospective, repeated experimental research design. Investigators utilized an accelerometer and an inductive plethysmography system to identify swallowing events and functional near-infrared spectroscopy (NIRS), a non-invasive cortical optical-imaging technique, to cortical responses to the peripheral stimulation conditions by measuring the hemodynamic responses in cortical oral-motor and sensorimotor regions. A repeated-measures ANOVA was performed on the participants’ swallowing frequency data with and without the stimulation conditions. The results indicated a significant difference (p \u3c .001) among the three conditions (no stimulation, pacifier stimulation, and vibrotactile stimulation), with pairwise comparisons indicating that the pacifier and vibrotactile conditions significantly (p \u3c .001) increased the infants’ swallowing frequency compared to swallowing frequency without stimulation. Swallowing frequency did not differ between the pacifier and vibrotactile conditions (p \u3e .05). NIRS recordings were obtained on only a few subjects for technical reasons. NIRS pilot data changes in blood flow occurred during the pacifier and vibrotactile stimulation conditions in a few infants. Overall findings suggest that both pacifier and vibrotactile stimulation can serve to up-regulate the frequency of swallowing in normal infants. Non-nutritive pacifier stimulation may be beneficial for increasing the frequency of swallowing in infants in addition to the known benefits of aiding in sucking skills development. Vibrotactile stimulation represents an alternative or complementary intervention for increasing the frequency of swallowing in infants that may not interfere with the process of oral intake. The current study continues to collect data for normal infants and should be explored in infants with disordered swallowing, particularly in the neonatal intensive care unit