No abstract

A cation-selective microfluidic sample preconcentration system is described. The cation sample was electropreconcentrated using a reversed-direction electroosmotic flow (EOF) and an anion-permselective filter, where an electric double layer (EDL) overlap condition existed. The anion-permselective filter between microchannels was fabricated by three different methods: 1) extending a positively charged, nanoporous, polymer membrane by photopolymerization of poly(diallyldimethylammonium chloride) (PDADMAC); 2) etching a nanochannel and then coating it with a positively-charged monomer, N-[3-(trimethoxysilyl)propyl]-N'-(4-vinylbenzyl)ethylenediamine hydrochloride (TMSVE); and, 3) etching a nanochannel and then coating it with a positively-charged, pre-formed polymer, polyE-323. The EOF direction in the microchannel was reversed by both TMSVE and polyE-323 coatings. The cation-selective preconcentration was investigated using charged fluorescent dyes and tetramethylrhodamine isothiocyanate (TRITC)-tagged peptides/proteins. The preconcentration in the three different systems was compared with respect to efficiency, dependence on buffer concentration and pH, tolerable flow rate, and sample adsorption. Both TMSVE- and polyE-323-coated nanochannels showed robust preconcentration at high flow rates, whereas the PDADMAC membrane maintained anion-permselectivity at higher buffer concentrations. The TMSVE-coated nanochannels showed a more stable preconcentration process, whereas the polyE-323-coated nanochannels showed a lower peptide sample adsorption and robust efficiency under a wide range of buffer pHs. The system described here can potentially be used for the preconcentration of cationic peptides/proteins on microfluidic devices for subsequent analyses.

Purpose: To illustrate what is inside the so-called black box of deep learning models (DLMs) so that clinicians can have greater confidence in the conclusions of artificial intelligence by evaluating adversarial explanation on its ability to explain the rationale of DLM decisions for glaucoma and glaucoma-related findings. Adversarial explanation generates adversarial examples (AEs), or images that have been changed to gain or lose pathologic characteristic-specific traits, to explain the DLM's rationale. Design: Evaluation of explanation methods for DLMs.

We developed a hands-free portable device which can provide two-way, real-time audio and video communication between hospital doctors and emergency medical technicians (EMTs) providing pre-hospital care. The device was based on an ultra mobile PC with a camera, a microphone/earphone set and a WIBRO modem for wireless Internet connection at an average data transmission rate of 1 Mbit/s. Feasibility tests were conducted in 55 real emergency situations over a period of three months at five different Rescue Centres in Seoul. Successful communication between an EMT and a doctor was achieved in 46 cases (84%). The device showed acceptable performance in terms of audio/video transmission time delays and maximum transmitted video frame rates, both outdoors, inside a building and in a moving vehicle at 70 km/h. Eight control centre staff and 11 EMTs who used the device completed a questionnaire. Despite acceptable basic performance, the device was found to be limited in terms of the contribution it made to the medical control of EMTs. However, improvements in device performance should produce higher quality pre-hospital emergency medical care in the future.

Motion artifact resulting from patient's movement is a significant source for disturbing accurate noninvasive blood pressure (NIBP) measurement. In an ambulance, patients are exposed to unstable circumstances due to vehicle's movement and vibration during emergency transportation. Since NIBP is indirectly measured using oscillometry based on the change of cuff pressure, it can be affected by motion artifact much more than other biosignals. In this paper, we developed a new NIBP system with improved accuracy by measuring acceleration of the system caused by patient's motion. The NIBP module including a 3-axis accelerometer was directly mounted on a cuff to minimize the interference induced through connecting tube. The results show that the proposed NIBP system has the capability to reject the interference of motion artifact effectively in an ambulance.