The finite-difference time-domain (FDTD) method has been widely used for the electromagnetic analysis of complex dispersive media. The shift-operator (SO)-FDTD or auxiliary differential equation ...(ADE)-FDTD formulation has been mainly employed for dusty plasma. Each FDTD formulation has its pros and cons. SO-FDTD is accurate but not computationally efficient. ADE-FDTD needs fewer computational resources, but its accuracy is poor. Here, we propose an accurate and efficient FDTD formulation for dusty plasma, based on the bilinear transform (BT). We perform a comprehensive study on the numerical permittivity and the computational efficiency for three FDTD formulations. Numerical examples are employed to illustrate that the proposed BT-FDTD outperforms the previously reported FDTD formulations for dusty plasma. In addition, based on the proposed BT-FDTD simulations, the effect of dust particles on EM wave propagation is investigated in the GHz band and the THz band.
The wide variability of isoniazid (INH) pharmacokinetics is mainly attributed to the trimodal N‐acetyltransferase 2 (NAT2) acetylator phenotype, that is, rapid, intermediate, and slow. Consequently, ...a uniform INH dose in current clinical practice may lead to treatment failure and emergence of drug resistance. There is a lack of studies on specific doses of INH for different NAT2 acetylator phenotypes among tuberculosis (TB) patients. Therefore, we aimed to provide insight into the optimal dosing of INH for each NAT2 acetylator phenotype with respect to the probability of achieving a pharmacokinetic (PK)/pharmacodynamic target. PK, the NAT2 genotype, and clinical data were collected in a multicenter prospective cohort study conducted at 13 clinical centers in Korea. Population PK modeling and simulation were carried out. Data from 454 TB patients were divided into a training data set and a test data set at a ratio of 4 to 1. The PK of the training data were best described by a 2‐compartment model with allometric scaling for body size effect. Importantly, NAT2 acetylator phenotypes significantly affected the apparent clearance. Our model, which provided better predictive performance compared with previously published models, was evaluated by external validation using the test set. The simulation for assessing target efficacy and toxicity indicated that the best INH dosing regimens for Korean tuberculosis patients were once‐daily doses of 400, 300, and 200 mg for rapid, intermediate, and slow acetylators, respectively. In conclusion, our study provides a step forward in precision dosing for antituberculosis management.
This study investigated the decoupling mechanism of capacitors in multiple-input-multiple-output (MIMO) antenna designs based on characteristic mode analysis (CMA). First, a two-port single-loop ...antenna, where shunt capacitor elements were used to obtain high port-to-port isolation properties, was analyzed. CMA revealed that the decoupling capacitors' mechanism lies in the modal superposition of the original radiation mode (Mode-2) and the manipulated high-order mode (Mode-3) with anti-phase current distributions. Accordingly, a compact four-port MIMO antenna module based on decoupling components (inductors and capacitors) was designed as the first of its kind. Both simulations and measurements were conducted to verify the feasibility of the proposed MIMO antenna module.
This study investigates the role of content and noncontent cues of tourism information quality in forming users’ destination image in social media. Empirical analysis based on data collected from ...Sina Weibo users suggests that several content cues and web page design as a noncontent cue are positively related with cognitive and affective images, which lead to a conative image. This study contributes to the body of knowledge on the role of tourism information quality in social media by providing empirical evidence on destination image formation. It also helps tourism managers build their marketing strategies to attract more tourists through social media.
When a longitudinal wave passes through a contact interface, second harmonic components are generated due to contact acoustic nonlinearity (CAN). The magnitude of the generated second harmonic is ...related to the contact state of the interface, of which a model has been developed using linear and nonlinear interfacial stiffness. However, this model has not been sufficiently verified experimentally for the case where the interface has a rough surface. The present study verifies this model through experiments using rough interfaces. To do this, four sets of specimens with different interface roughness values (Ra = 0.179 to 4.524 μm) were tested; one set consists of two Al6061-T6 blocks facing each other. The second harmonic component of the transmitted signal was analyzed while pressing on both sides of the specimen set to change the contact state of the interface. The experimental results showed good agreement with the theoretical prediction on the rough interface. The magnitude of the second harmonic was maximized at a specific contact pressure. As the roughness of the contact surface increased, the second harmonic was maximized at a higher contact pressure. The location of this maximal point was consistent between experiments and theory. In this study, an FEM simulation was conducted in parallel and showed good agreement with the theoretical results. Thus, the developed FEM model allows parametric studies on various states of contact interfaces.
Abstract
Diesel exhaust particles (DEPs), traffic-related air pollutants, are considered environmental factors adversely affecting allergic diseases. However, the immunological basis for the adjuvant ...effects of DEP in allergic rhinitis (AR) remains unclear. Therefore, this study aimed to investigate the effect of DEP exposure on AR using a mouse model. BALB/c mice sensitized to house dust mite (HDM) were intranasally challenged with HDM in the presence and absence of DEP. Allergic symptom scores, serum total and HDM-specific immunoglobulins (Igs), eosinophil infiltration in the nasal mucosa, cytological profiles in bronchoalveolar lavage fluid (BALF), and cytokine levels in the nasal mucosa and spleen cell culture were analyzed. Mice co-exposed to HDM and DEP showed increased allergic symptom scores compared with mice exposed to HDM alone. Reduced total IgE and HDM-specific IgE and IgG1 levels, decreased eosinophil infiltration in the nasal mucosa, and increased proportion of neutrophils in BALF were found in mice co-exposed to HDM and DEP. Interleukin (IL)-17A level was found to be increased in the nasal mucosa of the co-exposure group compared with that in the HDM-exposed group. The levels of IL-4, IL-13, interferon-γ, IL-25, IL-33, and TSLP expression showed no difference between the groups with and without DEP treatment. Increased expression of IL-17A in the nasal mucosa may contribute to DEP-mediated exacerbation of AR in HDM-sensitized murine AR model.
A 24 GHz Industrial, Scientific, and Medical (ISM)-band Doppler radar antenna with high isolation is proposed for moving target sensing applications. Both transmit (Tx) and receive (Rx) antennas ...consist of 2 × 2 microstrip patch antenna arrays. High isolation of the proposed antenna is achieved by inserting periodic Jerusalem cross slot array between Tx port and Rx port, and thus the surface wave from Tx port to Rx port is significantly suppressed. The −10 dB reflection coefficient bandwidth of the proposed antenna is 510 MHz, and the isolation between Tx port and Rx port is higher than 36.7 dB over the 24 GHz ISM band. The simulated half-power beamwidths are 58.53° for E -plane and 47.54° for H -plane. Experimental results show that high isolation can lead to improve Doppler radar performance. The proposed antenna can be a good candidate for contact-free monitoring of the heart rate and respiration rate in healthcare applications.
There were five sesquiterpene lactones, belonging to the eudesmanolide class, isolated from the halophyte
DC. The structures of the compounds were determined using spectroscopic methods, including 1D ...and 2D NMR spectra, MS data, and optical rotation values. Compounds
and
were characterized by the position of
-hydroxyphenylacetyl group in the sugar moiety. In the evaluation of anti-inflammatory effects on LPS-activated RAW264.7 macrophages, compound
, 5α,6βH-eudesma-3,11(13)-dien-12,6α-olide, potently suppressed the expression of iNOS and COS-2, as well as the production of TNF-α, IL-6, and IL-10. Treatment of
regulates the Nrf2/HO-1 pathway.
•The nonlinear ultrasonic characteristic in heat-treated Al 6061-T6 was investigated.•The nonlinearity parameter and the yield strength were measured for aged specimens.•The nonlinearity parameter ...and yield strength showed an interesting correlation.•The variation of nonlinearity parameter was explained by the precipitation sequence.•The nonlinearity parameter can be used to obtain the maximum strength of Al 6061-T6.
It is well known that nonlinear ultrasound is sensitive to certain microstructural features in materials such as dislocations and precipitates. This paper investigates the dependence of the nonlinear ultrasonic characteristic on MgnSim precipitation in heat-treated Al 6061-T6 alloy specimens. The specimens were heat-treated at a constant temperature of 220°C for different exposure times up to 6000min. The accuracy of the ultrasonic measurement setup that determines the absolute ultrasonic nonlinearity parameter βu was first validated. The nonlinearity parameter and the yield strength were measured for each of the artificially aged specimens. The experimental results show fluctuations in the nonlinearity parameter and yield strength over the aging time, but with an interesting correlation between the nonlinearity parameter and the yield strength over the aging time. Microstructural observations confirmed that those fluctuations are due to the formation and evolution of precipitates that occurs in a unique precipitation sequence in this alloy. These results suggest that the nonlinear ultrasonic measurement can be useful for monitoring second phase precipitation and related mechanical properties in the Al 6061-T6 alloy.
Objective:
The objective of this study was to assess the quality and accuracy of visual abstracts published in academic surgical journals.
Background:
Visual abstracts are commonly used to ...disseminate medical research findings. They distill the key messages of a research article, presenting them graphically in an engaging manner so that potential readers can decide whether to read the complete manuscript.
Methods:
We developed the Visual Abstract Assessment Tool based upon published guidelines. Seven reviewers underwent iterative training to apply the tool. We collected visual abstracts published by 25 surgical journals from January 2017 to April 2021; those corresponding to systematic reviews without meta-analysis, conference abstracts, narrative reviews, video abstracts, or nonclinical research were excluded. Included visual abstracts were scored on accuracy (as compared with written abstracts) and design, and were given a “first impression” score.
Results:
Across 25 surgical journals 1325 visual abstracts were scored. We found accuracy deficits in the reporting of study design (35.8%), appropriate icon use (49%), and sample size reporting (69.2%), and design deficits in element alignment (54.8%) and symmetry (36.1%). Overall scores ranged from 9 to 14 (out of 15), accuracy scores from 4 to 8 (out of 8), and design scores from 3 to 7 (out of 7). No predictors of visual abstract score were identified.
Conclusion:
Visual abstracts vary widely in quality. As visual abstracts become integrated with the traditional components of scientific publication, they must be held to similarly high standards. We propose a checklist to be used by authors and journals to standardize the quality of visual abstracts.
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