ACCURACY OF THE SOFTWARE GENLOCK WITH DIGITAL CAMCORDERS

Recently, digital camcorders have gained popularity as a viable means of recording movements in video motion analysis, mainly due to the ease of use and reasonably high image resolution. Digital camcorders, however, suffer from a major drawback, lack of the hardware genlock capability. Camcorders thus operate independently from each other and introduce time offsets among themselves. These time offsets in turn violate the requirement of simultaneous observations from multiple cameras in the 3·D analysis, producing erroneous real-life coordinates of the markers. This is especially true in fast motions, in which a small time offset can be translated into a large spatial error, and the time offsets must be corrected before the 3-D reconstruction. The genlock (synchronization) of the cameras can be potentially achieved by a software-based strategy, the software genlock. The purpose of this stUdy was to investigate the accuracy of the software genlock using digital camcorders

Size distributions of atmospheric particulate matter and associated trace metals in the multi-industrial city of Ulsan, Korea

Particulate matter (PM) was collected using micro-orifice uniform deposit impactors from a residential (RES) site and an industrial (IND) site in Ulsan, South Korea, in September-October 2014. The PM samples were measured based on their size distributions (11 stages), ranging from 0.06 ??m to over 18.0 ??m. Nine trace metals (As, Se, Cr, V, Cd, Pb, Ba, Sb, and Zn) associated with PM were analyzed. The PM samples exhibited weak bimodal distributions irrespective of sampling sites and events, and the mean concentrations of total PM (TPM) measured at the IND site (56.7 ??g/m3) was higher than that measured at the RES site (38.2 ??g/m3). The IND site also showed higher levels of nine trace metals, reflecting the influence of industrial activities and traffic emissions. At both sites, four trace metals (Ba, Zn, V, and Cr) contributed to over 80% of the total concentrations in TPM. The modality of individual trace metals was not strong except for Zn; however, the nine trace metals in PM2.5 and PM10 accounted for approximately 50% and 90% of the total concentrations in TPM, respectively. This result indicates that the size distributions of PM and trace metals are important to understand how respirable PM affects public health

The effect of ephedrine on intraoperative hypothermia

BACKGROUND: Prevention of intraoperative hypothermia has become a standard of operative care. Since ephedrine has a thermogenic effect and it is frequently used to treat hypotension during anesthesia, this study was designed to determine the effect of ephedrine on intraoperative hypothermia of patients who are undergoing spine surgery. METHODS: Twenty-four patients were randomly divided to receive an ephedrine (the ephedrine group, n = 12) or normal saline (the control group, n = 12) infusion for 2 h. The esophageal temperature (the core temperature), the index finger temperature (the peripheral temperature) and the hemodynamic variables such as the mean blood pressure and heart rate were measured every 15 minutes after the intubation. RESULTS: At the end of the study period, the esophageal temperature and hemodynamic variables were significantly decreased in the control group, whereas those in the ephedrine group were stably maintained. The index finger temperature was significantly lower in the ephedrine group compared to that in the control group, suggesting the prevention of core-to-peripheral redistribution of the heat as the cause of temperature maintenance. CONCLUSIONS: An intraoperative infusion of ephedrine minimized the decrease of the core temperature and it stably maintained the hemodynamic variables during spine surgery with the patient under general anesthesia.ope

Recovery without neurological sequelae of traumatic spinal epidural hematoma masquerading as Guillain-Barré syndrome in a child

Spinal cord lesions could mimic Guillain-Barré syndrome (GBS). Misdiagnosis as GBS can incur severe neurologic sequelae. We report the case of a previously healthy, 14-year-old boy with traumatic spinal epidural hematoma masquerading as GBS. He presented with sudden onset of tingling sensation on both hands and feet, which progressed into motor weakness of both legs. No abnormalities were found in brain magnetic resonance imaging and cerebrospinal fluid study. Despite intravenous immunoglobulin therapy for presumed GBS, the weakness progressed rapidly over 8 hours, resulting in complete loss of sensorimotor function below T4 level and loss of deep tendon reflexes. Whole spine magnetic resonance imaging showed a large epidural hematoma over the C5-T5 level. We found that he had experienced whiplash injury on an amusement ride about 3 weeks before. He underwent emergency decompressive laminectomy and hematoma removal, followed by vigorous rehabilitation treatment. On the fifth week of follow-up, he recovered from the complete loss of sensorimotor function. Thorough review of detailed history in emergency departments is required for children presenting with ascending paralysis. Also, rapid diagnostic and therapeutic interventions are crucial for maximum recovery of neurologic symptoms

Cooperative Spatial Retreat for Resilient Drone Networks

Drones are broadening their scope to various applications such as networking, package delivery, agriculture, rescue, and many more. For proper operation of drones, reliable communication should be guaranteed because drones are remotely controlled. When drones experience communication failure due to bad channel condition, interference, or jamming in a certain area, one existing solution is to exploit mobility or so-called spatial retreat to evacuate them from the communication failure area. However, the conventional spatial retreat scheme moves drones in random directions, which results in inefficient movement with significant evacuation time and waste of battery lifetime. In this paper, we propose a novel spatial retreat technique that takes advantage of cooperation between drones for resilient networking, which is called cooperative spatial retreat (CSR). Our performance evaluation shows that the proposed CSR significantly outperforms existing schemes. © 2017 by the authors. Licensee MDPI, Basel, Switzerland.1