Tail-scope: Using friends to estimate heavy tails of degree distributions in large-scale complex networks

Many complex networks in natural and social phenomena have often been characterized by heavy-tailed degree distributions. However, due to rapidly growing size of network data and concerns on privacy issues about using these data, it becomes more difficult to analyze complete data sets. Thus, it is crucial to devise effective and efficient estimation methods for heavy tails of degree distributions in large-scale networks only using local information of a small fraction of sampled nodes. Here we propose a tail-scope method based on local observational bias of the friendship paradox. We show that the tail-scope method outperforms the uniform node sampling for estimating heavy tails of degree distributions, while the opposite tendency is observed in the range of small degrees. In order to take advantages of both sampling methods, we devise the hybrid method that successfully recovers the whole range of degree distributions. Our tail-scope method shows how structural heterogeneities of large-scale complex networks can be used to effectively reveal the network structure only with limited local information.Comment: 9 pages, 6 figure

REACTION CHARACTERISTICS OF TWO WATER GAS SHIFT CATALYSTS IN A BUBBLING FLUIDIZED BED REACTOR FOR SEWGS PROCESS

Reaction characteristics of two WGS catalysts for SEWGS process were investigated in a bubbling fluidized bed reactor. The commercial low temperature WGS catalyst produced by Süd-chemie and new catalyst produced by spray-drying method were used as bed materials. Reaction temperature, steam/CO ratio, and gas velocity were considered as experimental variables. Moreover, long-term operation results of two WGS catalysts were compared as well

A highly sensitive and selective viral protein detection method based on RNA oligonucleotide nanoparticle

Globally, approximately 170 million people (representing approximately 3% of the population worldwide), are infected with hepatitis C virus (HCV) and at risk of serious liver disease, including chronic hepatitis. We propose a new quantum dots (QDs)-supported RNA oligonucleotide approach for the specific and sensitive detection of viral protein using a biochip. This method was developed by immobilizing a HCV nonstructural protein 5B (NS5B) on the surface of a glass chip via the formation of a covalent bond between an amine protein group and a ProLinker™ glass chip. The QDs-supported RNA oligonucleotide was conjugated via an amide formation reaction from coupling of a 5′-end-amine-modified RNA oligonucleotide on the surface of QDs displaying carboxyl groups via standard EDC coupling. The QDs-conjugated RNA oligonucleotide was interacted to immobilized viral protein NS5B on the biochip. The detection is based on the variation of signal of QDs-supported RNA oligonucleotide bound on an immobilized biochip. It was demonstrated that the value of the signal has a linear relationship with concentrations of the HCV NS5B viral protein in the 1 μg mL−1 to 1 ng mL−1 range with a detection limit of 1 ng mL−1. The major advantages of this RNA-oligonucleotide nanoparticle assay are its good specificity, ease of performance, and ability to perform one-spot monitoring. The proposed method could be used as a general method of HCV detection and is expected to be applicable to other types of diseases as well

Impact of non-pharmaceutical interventions on the rate of respiratory viruses other than severe acute respiratory syndrome coronavirus 2 in the coronavirus disease 2019 pandemic

Purpose We aimed to evaluate the impact of non-pharmaceutical interventions (NPIs) on the transmission of respiratory viruses other than severe acute respiratory syndrome coronavirus 2 among children during the coronavirus disease 2019 pandemic. Methods We analyzed the clinical and polymerase chain reaction (PCR) findings using electronic medical records of children (< 18 years) with fever or respiratory symptoms who were hospitalized via the emergency department of Wonkwang University Hospital (Iksan, Korea), from March 2018 through December 2021. The children were divided into before and after groups based on the hospitalization date relative to February 2020, starting point of the implementation of NPIs. PCR was performed using nasopharyngeal swab samples. Between the 2 groups, we compared age, sex, length of hospital stay, and PCR findings. Results The before and after groups consisted of 3,160 and 989, respectively, showing a 68.7% decrease in the number of children undergoing PCRs after the implantation of NPIs. The after group showed higher median values of the age and length of hospital stay than the before group (Ps < 0.001). A 76.9% decrease was noted in the number of children having PCR positivities (from 1,101 [34.8%] to 254 [25.7%]; P < 0.001). Among detected viruses, an increase in the proportion was noted only in human bocavirus (from 81 [2.6%] to 54 [5.5%]; P < 0.001). In contrast, significant decreases in the proportions were found in adenovirus, enterovirus, influenza A and B, respiratory syncytial viruses A and B, human coronaviruses (229E, NL63, and OC43) and human metapneumovirus. Conclusion NPIs may be effective in reducing the transmission of respiratory viruses other than severe acute respiratory syndrome coronavirus 2 among children during the pandemic

THE HOT GAS DESULFURIZATION IN A COMPACT TWO BEDS SYSTEM INTEGRATED WITH COAL GASIFICATION AND FISHER-TROPSCH SYSTEM

The hot gas desulfurization (HGD) technique is one of the elemental technologies of syngas purification having both thermal efficiency and very low emissions. The HGD is a novel method to efficiently remove H2S and COS in the syngas with regenerable sorbents at high temperature and high pressure condition. We propose a compact hot gas desulfurization system by which its operability is improved in stabilizing pressure balances among units. The proposed compact two beds system has two bubbling beds, solid injection nozzle, solid conveying line, and riser. The compact desulfurization system was located between coal gasifier and Fisher-Tropsch (F-T) reactor to desulfurize syngas in order not to deactivate F-T catalyst. To check feasibility of the compact desulfurization system at high pressure condition, both cold mode and hot mode tests have been performed. In the integrated system, the compact desulfurization system has removed H2S and COS in the syngas and supplied the cleaned syngas to the F-T reactor during the continuous operation at high pressure condition