Grid composite meta-surface absorber with thermal isolation structure for terahertz detection.

This paper specifically focuses on the absorber, the critical component responsible for the detector's response performance. The meta-surface absorber combines two resonant structures and achieves over 80% absorptance around 210 GHz, resulting in a broad operating frequency range. FR-4 is selected as the dielectric layer to be compatible with standard printed circuit board (PCB) technology, which reduces the overall fabrication time and cost. The absorbing unit and array layout are symmetrically designed, providing stable absorptance performance even under incident waves of different polarization angles. The polarization-insensitive absorptance characteristic further enhances the compatibility between the absorber and the detector in the application scenario. Furthermore, the thermal insulation performance of the absorber is ensured by introducing thermal insulation gaps. After completing fabrication through PCB technology, testing revealed that the absorber maintained excellent absorptance performance within its primary operating frequency range. This performance consistency closely matched the simulation results.

Efficacy, safety, and cost-effectiveness of therapeutic drug monitoring (TDM) for TNF inhibitor therapy in rheumatic disease: A systematic review and meta-analysis.

OBJECTIVE: The benefits of TDM-guided TNFi therapy in patients with rheumatic disease was still controversial. This systematic review and meta-analysis was conducted to explore if the TDM-guided TNFi therapy is superior to empirical-guided therapy. METHODS: We systematically searched PubMed, Web of Science, Cochrane Library, and EMBASE databases for articles published between database inception and October 05, 2023. Studies reporting endpoints in TDM-guided TNFi therapy and empirical therapy were included. Results would be presented in risk ratio (RR) and mean difference, with 95 % confidence interval (CI) reported. This study is registered with PROSPERO (CRD42022353956). RESULTS: A total of 14 studies (eight RCTs and six cohort studies) involving 2427 patients were included in this meta-analysis. In the scenario of response prediction, compared with empirical-guided therapy, TDM-guided TNFi therapy had association with higher treat-to-target rates (RR 1.30, 95 % CI 1.02-1.65, P=0.03, I2=79 %), more specifically, higher low disease activity rates (RR 2.11, 95 % CI 1.22-3.66, P=0.007, I2=61 %), but no difference in clinical remission rates (RR 0.98,95 % CI 0.87-1.11, P=0.75, I2=0 %). In the scenario of dose reduction prediction, lower relapse rates (RR 0.73, 95 % CI 0.65-0.82, P <0.00001, I2=0 %) were observed compared with empirical-guided dose reduction strategy, but no difference (RR 1.24, 95 % CI 0.85-1.80, P=0.27, I2=57 %) between TDM-guided dose reduction and standard-dosing therapy. No significant difference was observed in change of disease activity score, mean disease activity score, radiographic progression, and safety. And TDM-guided therapy was associated with reduced cost per patient per year calculated as the total accumulated sum of therapy cost. CONCLUSION: TDM-guided TNFi therapy was associated with increased rates of low disease activity and decreased risks of relapse, and may save cost compared with empirical-guided therapy in patients with rheumatic disease. But this does not mean that the use of TDM-guided TNFi therapy can be advocated, because there is no difference in clinical remission rates and many other outcomes. More researches, especially randomized clinical trials are needed to verify this conclusion in the future.

Switchable metasurface for high-efficiency absorption and broadband polarization conversion based on vanadium dioxide in the terahertz frequency.

High-performance devices with superior execution will facilitate the practical application of terahertz (THz) technology and foster THz innovation. In this paper, taking advantage of the phase transition characteristics of vanadium dioxide (V O 2), a reconfigurable metasurface with absorption and polarization conversion capacities is proposed. The metallic condition of V O 2 results in the formation of a wideband absorber. It provides more than 90% absorption over a broad spectral range from 3.32 to 5.30 THz. Due to the regularity of the meta-atom, the absorber is not polarization-delicate and keeps a high retention rate in the scope of incoming angles from 0° to 45°. When V O 2 is in the insulating condition, the calculated outcomes demonstrate that the cross-polarization conversion rate can reach more than 90% in the range of 2.29-7.85 THz when x-polarized or y-polarized waves are incident vertically. The proposed metasurface is likely to be used in the fields of emitters, sensors, imaging systems, and wireless communication.

Antibacterial Effect of Cell-Free Supernatant from Lactobacillus pentosus L-36 against Staphylococcus aureus from Bovine Mastitis.

This study sought to analyze the main antibacterial active components of Lactobacillus pentosus (L. pentosus) L-36 cell-free culture supernatants (CFCS) in inhibiting the growth of Staphylococcus aureus (S. aureus), to explore its physicochemical properties and anti-bacterial mechanism. Firstly, the main antibacterial active substance in L-36 CFCS was peptides, which inferred by adjusting pH and enzyme treatment methods. Secondly, the physicochemical properties of the antibacterial active substances in L-36 CFCS were studied from heat, pH, and metal ions, respectively. It demonstrated good antibacterial activity when heated at 65 °C, 85 °C and 100 °C for 10 and 30 min, indicating that it had strong thermal stability. L-36 CFCS had antibacterial activity when the pH value was 2-6, and the antibacterial active substances became stable with the decrease in pH value. After 10 kinds of metal ions were treated, the antibacterial activity did not change significantly, indicating that it was insensitive to metal ions. Finally, scanning electron microscopy, transmission electron microscopy and fluorescence probe were used to reveal the antibacterial mechanism of S. aureus from the aspects of cell morphology and subcellular structure. The results demonstrated that L-36 CFCS could form 1.4-2.3 nm pores in the cell membrane of S. aureus, which increased the permeability of the bacterial cell membrane, resulting in the depolarization of cell membrane potential and leakage of nucleic acid protein and other cell contents. Meanwhile, a large number of ROS are produced and accumulated in the cells, causing damage to DNA, and with the increase in L-36 CFCS concentration, the effect is enhanced, and finally leads to the death of S. aureus. Our study suggests that the main antibacterial active substances of L-36 CFCS are peptides. L-36 CFCS are thermostable, active under acidic conditions, insensitive to metal ions, and exhibit antibacterial effects by damaging cell membranes, DNA and increasing ROS. Using lactic acid bacteria to inhibit S. aureus provides a theoretical basis for the discovery of new antibacterial substances, and will have great significance in the development of antibiotic substitutes, reducing bacterial resistance and ensuring animal food safety.

A Terahertz Optomechanical Detector Based on Metasurface and Bi-Material Micro-Cantilevers.

Terahertz imaging technology has shown great potential in many fields. As the core component of terahertz imaging systems, terahertz detectors have received extensive attention. In this paper, a metasurface-based terahertz optomechanical detector is proposed, which is made of two fabrication-friendly materials: gold and silicon nitride. The optomechanical detector is essentially a thermal detector composed of metasurface absorber, bi-material micro-cantilevers and heat insulation pillars. Compared with traditional thermal terahertz detectors, the optomechanical detector employs a metasurface absorber as the terahertz radiation coupler and obtains an absorptivity higher than 90% from 3.24 to 3.98 THz, which is much higher than that of traditional terahertz detectors with absorbers made from natural materials. Furthermore, the detector is fabricated by MEMS process and its responsivity has been verified by a specifically designed optical read-out system; the measured optomechanical responsivity is 24.8 µm/µW, which agrees well with the multi-physics simulation. These results indicated that the detector can be employed as a pixel to form a terahertz focal plane array in the future, and further realize real-time terahertz imaging at room temperature.

Emerging Roles of Pleckstrin-2 Beyond Cell Spreading.

Pleckstrin-2 is a member of pleckstrin family with well-defined structural features that was first identified in 1999. Over the past 20 years, our understanding of PLEK2 biology has been limited to cell spreading. Recently, increasing evidences support that PLEK2 plays important roles in other cellular events beyond cell spreading, such as erythropoiesis, tumorigenesis and metastasis. It serves as a potential diagnostic and prognostic biomarker as well as an attractive target for the treatment of cancers. Herein, we summary the protein structure and molecular interactions of pleckstrin-2, with an emphasis on its regulatory roles in tumorigenesis.

[Study of the "weekend effect" of O3, NOx and other pollutants in summer of Beijing].

The data of O3, NOx (NO and NO2), CO and SO2 observed at Beijing 325m meteorological tower from June 25 to July 7, 2000 and from July 26 to August 22, 2000 are used to analyze the difference of pollutant concentrations on weekends and weekdays, and its causes. Results show that except SO2, the correlations of O3, NOx, NO, NO2 and CO concentrations between weekends and weekdays are very significant,since they all pass the t-test significance level at alpha = 0.05. The correlation coefficients (R) are 0.99, 0.61, 0.56, 0.80 and 0.61 for O3, NOx, NO, NO2 and CO3, respectively. Weekend NO, and CO concentrations are lower than weekday concentrations in rush hours (06:00-08:00), and the mean deviations for NOx and CO concentrations are -28% and -9%, respectively. The regression coefficient of O3 concentrations between weekends and weekdays is 1.25 +/- 0.02. Furthermore, the maximum 1-h average O3 concentration and maximum 8-h average O3 concentration on weekends are 23% and 26% higher than those on weekdays, respectively, indicating an obvious O3 "weekend effect".

[Smog chamber simulation of atmospheric photochemical reactions of acetylene and NO(x)].

A series of characteristic experiments were conducted in a self-made photochemical smog chamber, which was used to simulate atmospheric photochemical reactions of acetylene and NO(x) under room temperature of (20 +/- 1) degrees C. The effect of acetylene and NO(x) on ozone production by photochemical reactions was discussed. The wall decay of O3 and NO2 were determined, which were 5.80 x 10(-6) s(-1) and 2.41 x 10(-6) s(-1), respectively. Such decay should be omitted relative to O3 and NO2 in simulative experiments. The effective light intensity for a single black lamp of 40 W was determined to be 0.64 x 10(-3) s(-1), which was expressed by the photolysis rate of NO2. The effect of different light intensity, initial concentrations of acetylene and NO(x) on O3 production was discussed after correction of background O3 from purified air. The incremental reactivity (IR) of acetylene were calculated. For four different experiments, the maximum values of IR are 1.76 x 10(-2), 2.68 x 10(-2), 2.04 x 10(-2) and 2.84 x 10(-2), respectively. It is found that there are close relationships between IR and initial acetylene concentrations, and between IR and irradiation intensity, and that there is no significant relation between IR and initial NO(x) concentrations.

[Analysis on concentration variety characteristics of atmospheric ozone under the boundary layer in Beijing].

Based on the atmospheric ozone sounding data, the average monthly and seasonal variety principles of atmospheric ozone concentration during six years are analyzed under the boundary layer in Beijing. The results show that the monthly variation of atmospheric ozone are obvious that the minimum values appear in January from less than 10 x 10(-9) on ground to less than 50 x 10(-9) on upper layer (2 km), but the maximum values appear in June from 85 x 10(-9) on ground to more than 90 x 10(-9) on upper layer. The seasonal variation is also clear that the least atmospheric ozone concentration is in winter and the most is in summer, but variety from ground to upper layer is largest in winter and least in summer. According to the type of outline, the outline of ozone concentration is composite of three types which are winter type, summer type and spring-autumn type. The monthly ozone concentration in different heights is quite different. After analyzing the relationship between ozone concentration and meteorological factors, such as temperature and humidity, we find ozone concentration on ground is linear with temperature and the correlation coefficient is more than 85 percent.

[The emission flux of volatile organic compounds in the Inner Mongolia Grassland].

During the summer season of 2002, emissions of volatile organic compounds were firstly measured by a static enclosure technique at a grassland site in the Inner Mongolia grassland. The parameters including solar radiation, air temperature and relative humidity were also measured in the same time period. The results showed that isoprene was the main component of volatile organic compounds emitted from the grassland. Isoprene exhibited an evident diurnal, daily and seasonal variation. Solar visible radiation, air temperature and water vapor content were the main factors to affect isoprene emission, and solar visible radiation was the most important factor to control the isoprene emission. Base on the correlation analysis, when considering the affecting factors of isoprene emission, it is not only to consider solar visible radiation, temperature, but also the water vapor. It is impossible to avoid the changes of solar radiation, temperature and humidity between inside and outside the chamber by using the enclosure technique. So, it is necessary to take these effects into the considerations and modify isoprene emission. In summer 2002, the maximum emission flux (C) of isoprene was 1649.3 micrograms/(m2.h), and monthly averaged emission flux (C) in June, August and September were 886.6, 707.0 and 427.2 micrograms/(m2.h), respectively.