Background: Prematurity can disrupt the development of a specialized neural circuit known as suck central pattern generator (sCPG), which often leads to poor feeding skills. The extent to which suck can be entrained using a synthetically patterned orocutaneous input to promote its development in preterm infants who lack a functional suck is unknown.Objective: To evaluate the effects of a new motorized 'pulsating' pacifier capable of entraining the sCPG in tube-fed premature infants who lack a functional suck and exhibit feeding disorders.Methods: Prospective cohort study of 31 preterm infants assigned to either the oral patterned entrainment intervention (study) or non-treated (controls) group, matched by gestational age, birth weight, oxygen supplementation history and oral feed status. Study infants received a daily regimen of orocutaneous pulse trains through a pneumatically controlled silicone pacifier concurrent with gavage feeds.Results: The patterned orocutaneous stimulus was highly effective in accelerating the development of non-nutritive suck (NNS) in preterm infants. A repeated-measure multivariate analysis of covariance revealed significant increases in minute rates for total oral compressions, NNS bursts, and NNS cycles, suck cycles per burst, and the ratiometric measure of NNS cycles as a percentage of total ororhythmic output. Moreover, study infants also manifest significantly greater success at achieving oral feeds, surpassing their control counterparts by a factor of 3.1 Â (72.8% daily oral feed versus 23.3% daily oral feed, respectively).Conclusion: Functional expression of the sCPG among preterm infants who lack an organized suck can be induced through the delivery of synthetically patterned orocutaneous pulse trains. The rapid emergence of NNS in treated infants is accompanied by a significant increase in the proportion of nutrient taken orally.

Objective-In 2009, the U.S. Environmental Protection Agency (EPA) proposed an impulse noise reduction rating (NRR) for hearing protection devices based upon the impulse peak insertion loss (IPIL) methods in the ANSI S12.42-2010 standard. This study tests the ANSI S12.42 methods with a range of hearing protection devices measured in field conditions. Design-The method utilizes an acoustic test fixture and three ranges for impulse levels: 130-134, 148-152, and 166-170 dB peak SPL. For this study, four different models of hearing protectors were tested: Bilsom 707 Impact II electronic earmuff, E·A·R Pod Express, E·A·R Combat Arms version 4, and the Etymotic Research, Inc. Electronic BlastPLG™ EB1.Study sample-Five samples of each protector were fitted on the fixture or inserted in the fixture's ear canal five times for each impulse level. Impulses were generated by a 0.223 caliber rifle.

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Objective-To characterize the integrity of non-nutritive suck (NNS) parameters among three groups of preterm infants ranging from normal to those with progressive degrees of respiratory distress syndrome (RDS).Study Design-NNS compression waveforms were sampled from 55 infants in the neonatal intensive care unit using a silicone pacifier electronically instrumented for intraluminal pressure. Seven select NNS parameters were measured at two different sessions, and statistically analyzed using a General Linear Model Analysis of Covariance.Results and Conclusions-Preterm infants with a more extensive history of RDS and oxygen therapy manifest significantly (p≤0.001) degraded performance on six of the seven NNS measures. This trend was disproportionately amplified in preterm infants with moderate-to-severe RDS. Prolonged periods of RDS requiring oxygen therapy may cause maladaptive orosensory experiences, and restrict oral movements which may contribute to delayed NNS development.

Objective To characterize the impulse noise exposure and auditory risk for youth recreational firearm users engaged in outdoor target shooting events. The youth shooting positions are typically standing or sitting at a table, which places the firearm closer to the ground or reflective surface when compared to adult shooters. Design Acoustic characteristics were examined and the auditory risk estimates were evaluated using contemporary damage-risk criteria for unprotected adult listeners and the 120-dB peak limit suggested by the World Health Organization (1999) for children. Study sample Impulses were generated by 26 firearm/ammunition configurations representing rifles, shotguns, and pistols used by youth. Measurements were obtained relative to a youth shooter’s left ear. Results All firearms generated peak levels that exceeded the 120 dB peak limit suggested by the WHO for children. In general, shooting from the seated position over a tabletop increases the peak levels, LAeq8 and reduces the unprotected maximum permissible exposures (MPEs) for both rifles and pistols. Pistols pose the greatest auditory risk when fired over a tabletop. Conclusion Youth should utilize smaller caliber weapons, preferably from the standing position, and always wear hearing protection whenever engaging in shooting activities to reduce the risk for auditory damage.