Three-Tier Capacity and Traffic Allocation for Core, Edges, and Devices for Mobile Edge Computing

In order to satisfy the 5G requirements of ultra-low latency, mobile edge computing (MEC)-based architecture, composed of three-tier nodes, core, edges, and devices, is proposed. In MEC-based architecture, previous studies focused on the controlplane issue, i.e., how to allocate traffic to be processed at different nodes to meet this ultra-low latency requirement. Also important is how to allocate the capacity to different nodes in the management plane so as to establish a minimal-capacity network. The objectives of this paper is to solve two problems: 1) to allocate the capacity of all nodes in MEC-based architecture so as to provide a minimal-capacity network and 2) to allocate the traffic to satisfy the latency percentage constraint, i.e., at least a percentage of traffic satisfying the latency constraint. In order to achieve these objectives, a two-phase iterative optimization (TPIO) method is proposed to try to optimize capacity and traffic allocation in MEC-based architecture. TPIO iteratively uses two phases to adjust capacity and traffic allocation respectively because they are tightly coupled. In the first phase, using queuing theory calculates the optimal traffic allocation under fixed allocated capacity, while in the second phase, allocated capacity is further reduced under fixed traffic allocation to satisfy the latency percentage constraint. Simulation results show that MEC-based architecture can save about 20.7% of capacity of two-tier architecture. Further, an extra 12.2% capacity must be forfeited when the percentage of satisfying latency is 90%, compared to 50%.This work was supported in part by H2020 collaborative Europe/Taiwan research project 5G-CORAL (grant number 761586), and Ministry of Science and Technology, Taiwan for financially supporting this research under Contract No. MOST 106-2218-E-009-018

Bacteremic pneumonia caused by Nocardia veterana in an HIV-infected patient

SummaryDisseminated Nocardia veterana infection has rarely been reported. We describe the first reported case of N. veterana bacteremic pneumonia in an HIV-infected patient. The isolate was confirmed by 16S rRNA sequencing analysis. The patient initially responded well to trimethoprim–sulfamethoxazole treatment (minimum inhibitory concentration 0.25μg/ml), but died of ventilator-associated pneumonia

Epidemiology of extended-spectrum β-lactamases in Enterobacterales in Taiwan for over two decades

The emergence of antimicrobial resistance among microorganisms is a serious public health concern, and extended-spectrum β-lactamases (ESBL)-producing Enterobacterales is one of the major concerns among antibiotic-resistant bacteria. Although the prevalence of ESBL in Enterobacterales has been increasing with time, the prevalence of ESBL could differ according to the species, hospital allocation, sources of infections, nosocomial or community acquisitions, and geographic regions. Therefore, we conducted a comprehensive review of the epidemiology of ESBL-producing Enterobacterales in Taiwan. Overall, the rates of ESBL producers are higher in northern regions than in other parts of Taiwan. In addition, the genotypes of ESBL vary according to different Enterobacterales. SHV-type ESBLs (SHV-5 and SHV-12) were the major types of Enterobacter cloacae complex, but Serratia marcescens, Proteus mirabilis, Escherichia coli, and Klebsiella pneumoniae were more likely to possess CTX-M-type ESBLs (CTX-M-3 and CTX-M-14). Moreover, a clonal sequence type of O25b-ST131 has been emerging among urinary or bloodstream E. coli isolates in the community in Taiwan, and this clone was potentially associated with virulence, ESBL (CTX-M-15) production, ciprofloxacin resistance, and mortality. Finally, the evolution of the genetic traits of the ESBL-producing Enterobacterales isolates helps us confirm the interhospital and intrahospital clonal dissemination in several regions of Taiwan. In conclusion, continuous surveillance in the investigation of ESBL production among Enterobacterales is needed to establish its long-term epidemiology

Databases in the Asia-Pacific Region: The Potential for a Distributed Network Approach

Background: This study describes the availability and characteristics of databases in Asian-Pacific countries and assesses the feasibility of a distributed network approach in the region. Methods: A web-based survey was conducted among investigators using healthcare databases in the Asia-Pacific countries. Potential survey participants were identified through the Asian Pharmacoepidemiology Network. Results: Investigators from a total of 11 databases participated in the survey. Database sources included four nationwide claims databases from Japan, South Korea, and Taiwan; two nationwide electronic health records from Hong Kong and Singapore; a regional electronic health record from western China; two electronic health records from Thailand; and cancer and stroke registries from Taiwan. Conclusions: We identified 11 databases with capabilities for distributed network approaches. Many country-specific coding systems and terminologies have been already converted to international coding systems. The harmonization of health expenditure data is a major obstacle for future investigations attempting to evaluate issues related to medical costs.postprin