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BackgroundFrontline health care workers, including physicians, are at high risk of contracting coronavirus disease (COVID-19) owing to their exposure to patients suspected of having COVID-19. ObjectiveThe aim of this study was to evaluate the benefits and feasibility of a double triage and telemedicine protocol in improving infection control in the emergency department (ED). MethodsIn this retrospective study, we recruited patients aged ≥20 years referred to the ED of the National Taiwan University Hospital between March 1 and April 30, 2020. A double triage and telemedicine protocol was developed to triage suggested COVID-19 cases and minimize health workers’ exposure to this disease. We categorized patients attending video interviews into a telemedicine group and patients experiencing face-to-face interviews into a conventional group. A questionnaire was used to assess how patients perceived the quality of the interviews and their communication with physicians as well as perceptions of stress, discrimination, and privacy. Each question was evaluated using a 5-point Likert scale. Physicians’ total exposure time and total evaluation time were treated as primary outcomes, and the mean scores of the questions were treated as secondary outcomes. ResultsThe final sample included 198 patients, including 93 cases (47.0%) in the telemedicine group and 105 cases (53.0%) in the conventional group. The total exposure time in the telemedicine group was significantly shorter than that in the conventional group (4.7 minutes vs 8.9 minutes, P

The variable spreading factor-orthogonal frequency and code division multiplexing (VSF-OFCDM) system has been proposed as the forward link interface for achieving a high data rate in fourth-generation (4G) mobile communications. VSF-OFCDM allocates the orthogonal channelization codes of an orthogonal variable spreading factor (OVSF) code tree in 2-D spreading in the time and frequency domains but suffers from two disadvantages, namely, moderate utilization and low transmission quality. Moderate utilization is caused by code blocking, and the low transmission quality is due to the multicode interference from high channel loading in the time domain of the 2-D spreading. A tradeoff thus exists between code blocking and multicode interference. A lower code blocking means a higher interference. Achieving high utilization while also providing high transmission quality is a critical issue that should be addressed in 4G VSF-OFCDM. Therefore, this paper proposes a 2-D spreading approach that is based on an adaptive load balancing with Markov decision process (which is denoted by ALM). The ALM approach consists of three phases. First, for balancing the channel load, the adaptive 2-D spreading phase is proposed to select the 2-D spreading combinations, which have low channel load and high frequency diversity, as the candidates. Second, a dynamic recombination of the 2-D spreading is presented to decrease the channel load while supporting the transmission quality from high frequency diversity if the channel load of a time-domain code exceeds the defined channel load threshold. Third, the cost-based Markov decision process (MDP) code-selection approach is adopted to minimize the code blocking. The MDP models the state of the OVSF code tree as an MDP and then defines the costs for all the candidate channelization codes. The MDP phase selects the least-cost channelization code as the optimal solution if several 2-D spreading combinations can satisfy the channel load limitation. Additionally, the time complexity of the ALM is analyzed. The numerical results indicate that the proposed approach outperforms the other approaches in transmission quality ratio, fractional reward loss, and total number of reassignments. Index Terms--Channel load, fourth generation (4G), frequency diversity gain, multicode interference, transmission quality, two-dimensional (2-D) spreading, variable spreading factor-orthogonal frequency and code division multiplexing (VSF-OFCDM).

A square planar metal-plate monopole antenna fed by using a novel trident-shaped feeding strip is presented. With the use of the proposed feeding strip, the square planar monopole antenna studied shows a very wide impedance bandwidth of about 10 GHz (about 1.4-11.4 GHz, bandwidth ratio about 1:8.3), which is larger than three times the bandwidth obtained using a simple feeding strip (about 1.5-3.3 GHz, bandwidth ratio about 1:2.3). In addition, the proposed feeding strip can be integrated with the square planar monopole, that is, the feeding strip and the square planar monopole together can be easily fabricated using a single metal plate, making the proposed antenna easy to construct at a low cost. Details of the experimental and simulation results for the proposed planar monopole antenna are presented and analyzed. Index Terms--Antennas, planar metal-plate monopole antenna, planar monopole antennas, ultrawide-band monopole antennas.

Abstract Background Gene transfer into many cell types has been successfully used to develop alternative and adjunct approaches to conventional medical treatment. However, effective transfection of postmitotic neurons remains a challenge. The aim of this study was to develop a method for gene transfer into rat primary dorsal root ganglion neurons using sonoporation. Methods Dissociated cells from adult rat dorsal root ganglion (DRG) cells were sonicated for 1-8 s at 2.5-10 W to determine the optimal ultrasound duration and power for gene transfection and cell survival. Transfection efficiency was compared between sonoporation, liposome and lentiviral vector gene transfer techniques. Results The optimum ultrasound intensity was 5 W for 2 s and yielded an efficiency of gene transfection of 31% and a survival rate of 35%. Conclusions Sonoporation can be optimized to minimize cell death and yield a high percentage of transfected neurons and that this technique can be easily applied to primary cultures of rat dorsal root ganglion neurons.

Abstract Background Several molecular changes occur following axotomy, such as gene up-regulation and down-regulation. In our previous study using Affymetrix arrays, it was found that after the axotomy of sciatic nerve, there were many novel genes with significant expression changes. Among them, neuronatin (Nnat) was the one which expression was significantly up-regulated. Nnat was identified as a gene selectively expressed in neonatal brains and markedly reduced in adult brains. The present study investigated whether the expression of Nnat correlates with symptoms of neuropathic pain in adult rats with transected sciatic nerve. Methods Western blotting, immunohistochemistry, and the Randall and Selitto test were used to study the protein content, and subcellular localization of Nnat in correlation with pain-related animal behavior. Results It was found that after nerve injury, the expression of Nnat was increased in total protein extracts. Unmyelinated C-fiber and thinly myelinated A-δ fiber in adult dorsal root ganglions (DRGs) were the principal sub-population of primary afferent neurons with distributed Nnat. The increased expression of Nnat and its subcellular localization were related to mechanical hyperalgesia. Conclusions The results indicated that there was significant correlation between mechanical hyperalgesia in axotomy of sciatic nerve and the increased expression of Nnat in C-fiber and A-δ fiber of adult DRG neurons.