Cochlear implant (CI) listeners show limits at high frequencies in tasks involving temporal processing such as rate pitch and interaural time difference discrimination. Similar limits have been observed in neural responses to electric stimulation in animals with CI; however, the upper limit of temporal coding of electric pulse train stimuli in the inferior colliculus (IC) of anesthetized animals is lower than the perceptual limit. We hypothesize that the upper limit of temporal neural coding has been underestimated in previous studies due to the confound of anesthesia. To test this hypothesis, we developed a chronic, awake rabbit preparation for single-unit studies of IC neurons with electric stimulation through CI. Stimuli were periodic trains of biphasic pulses with rates varying from 20 to 1280 pulses per second. We found that IC neurons in awake rabbits showed higher spontaneous activity and greater sustained responses, both excitatory and suppressive, at high pulse rates. Maximum pulse rates that elicited synchronized responses were approximately two times higher in awake rabbits than in earlier studies with anesthetized animals. Here, we demonstrate directly that anesthesia is a major factor underlying these differences by monitoring the responses of single units in one rabbit before and after injection of an ultra-short-acting barbiturate. In general, the physiological rate limits of IC neurons in the awake rabbit are more consistent with the psychophysical limits in human CI subjects compared with limits from anesthetized animals.

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Objective To document the experiences of converting a general hospital to a coronavirus disease 2019 (COVID-19) designated hospital during an outbreak in Daegu, Republic of Korea. Methods The hospital management formed an emergency task force team, whose role was to organize the COVID-19 hospital. The task force used different collaborative channels to redistribute resources and expertise to the hospital. Leading doctors from the departments of infectious diseases, critical care and pulmonology developed standardized guidelines for treatment coherence. Nurses from the infection control team provided regular training on donning and doffing of personal protective equipment and basic safety measures. Findings Keimyung University Daegu Dongsan hospital became a red zone hospital for COVID-19 patients on 21 February 2020. As of 29 June 2020, 1048 COVID-19 patients had been admitted to the hospital, of which 22 patients died and five patients were still being treated in the recovery ward. A total of 906 health-care personnel worked in the designated hospital, of whom 402 were regular hospital staff and 504 were dispatched health-care workers. Of these health-care workers, only one dispatched nurse acquired COVID-19. On June 15, the hospital management and Daegu city government decided to reconvert the main building to a general hospital for non-COVID-19 patients, while keeping the additional negative pressure rooms available, in case of resurgence of the disease. Conclusion Centralized coordination in frontline hospital operation, staff management, and patient treatment and placement allowed for successful pooling and utilization of medical resources and manpower during the COVID-19 outbreak.

Foreign bodies (FB) in the external auditory canal are relative medical emergency. The objective of this study was to describe the types of FB and their complications and to highlight on new FB not seen before which was the bluetooth devices that were used for cheating during high school examination in Al-Fallujah city. This was a two-year hospital-based descriptive study performed in the Department of Ear, Nose and Throat (ENT), Al-Fallujah General Hospital, from June 2011 to May 2013; during this period, 224 FB had been extracted from 224 patients. Beads were extracted from 68 patients (30.4%), cotton tips were extracted from 50 patients (22.3%), seeds and garlic were extracted from 31 patients (13.8%), papers were extracted from 27 patients (12.1%), insects were extracted from 24 patients (10.7%), button batteries were extracted from 13 patients (5.8%), and bluetooth devices were extracted from 7 patients (3.1%). Most of the cases did not develop complications (87.5%) during extraction. The main complications were canal abrasion (4.5%). Proper instrumentation allows the uncomplicated removal of many FB. The use of general anesthesia is preferred in very young children. Bluetooth device objects should be considered as new aural FB, especially in our territory.