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The long-term stability of the cast-in-place footings in permafrost regions has received much attention due to its climate sensitivity. The current research lacks long-term data validation, especially in the context of climate change. Based on the 13-year (2011–2023) temperature and deformation monitoring data from the Qinghai‒Tibet Power Transmission Line, this study investigates the characteristics of permafrost variation and its impact on the stability of tower footings under the cooling effect from thermosyphons. The results reveal that the thermosyphons effectively reduce the ground temperature around the footings. After the first freeze‒thaw cycle, the soil around the tower footings completed refreezing and maintained a frozen state. In the following 13 years, the ground temperature continued to decrease due to the cooling effect of thermosyphons. The duration notably exceeded the previously predicted 5 years. The temperature reduction at the base of the footings corresponded well with the frost jacking of the tower footings and could be divided into three distinct phases. In phase 1, the ground temperature around the footings rapidly reduced, approaching that of the natural field, while the footings experienced pronounced deformation. In phase 2, the ground temperature decreased at a faster rate, and the deformation rate of the footings slowed down. In phase 3, the frost jacking of the footings gradually retarded with the decrease in base temperature. Additionally, the ground temperature differences of over 1 °C were observed among different tower footings, which may lead to the differential deformation among the tower footings. The ground temperature differentiation is attributed to the difference in solar radiation intensity, which is shaded by the tower structure from different directions. This study provides theoretical support and empirical accumulation for the construction and maintenance of tower footings in permafrost regions.

Insects have sensitive olfactory systems to interact with environment and respond to the change in host plant conditions. Key genes in the system can be potential targets for developing new and efficient pest behaviour control methods. Riptortus pedestris is an important soybean pest in East Asia and has caused serious damage to the soybean plants in Huang-Huai-Hai region of China. However, the current treatment of pests is dominated by chemical insecticides and lacks efficient sustainable prevention and control technologies. In this study, we identified 49 putative odorant-binding proteins (OBPs) (43 were new genes) and 25 chemosensory proteins (CSPs) (17 were new genes) in R. pedestris genome. These OBP and CSP genes are clustered in highly conserved groups from other hemipteran species in phylogenetic trees. Most RpedOBPs displayed antennal-biased expression. Among the 49 RpedOBPs, 33 were significantly highly expressed in the antennae, including three male-biased and nine female-biased. While many RpedCSPs were detected both in the antennae and in non-antennal tissues, only 11 RpedCSPs displayed antennal-biased expression, in which four RpedCSPs were male-biased and five RpedCSPs were female-biased. Some OBP and CSP genes showed sex-biased expression profiles. Our results not only provide a foundation for future exploration of the functions of RpedOBPs and RpedCSPs but also aid in developing environmentally friendly insecticides in the future.

Single crystal perovskite materials with the intriguing properties of wide optical absorption range, low trap density, photoluminescence, and superior charge-transfer have emerged as a new class of revolutionary photovoltaic semiconductors promising for various applications. A technique to realize microstructures or microdevices on the surface of single crystal can facilitate the incorporation of these materials into optoelectronic applications. Here, we first reported the fabrication of 1-D mciropores, microlines, and 2-D micropatterns such as word “USTC,” number “2016” and “Olympic rings” on the surface of CH3NH3PbI3 single crystal by femtosecond laser ablating. The effect of parameters such as exposure time, laser peak intensity, and scanning speed was quantitatively investigated to determine the parameter intervals capable of ensuring the required resolution. By fabricating periodic grating microstructures, the perovskite surfaces showed bright iridescence from dark blue to red due to the grating diffraction effect. Moreover, it is found that the fluorescence peak strength of processed area obviously grows with laser peak intensity and scanning speed, which is attributed to the increasing surface roughness caused by higher laser peak intensity and slower scanning speed. These works are beneficial for researchers to better understand the intrinsic property of single crystal perovskite and accelerate perovskite-based optoelectronics applications.

Presents corrections to the paper, "Femtosecond laser direct ablating micro/nanostructures and micropatterns on CH3NH3PbI3 single crystal" (Wang, C.W., et al), IEEE Photon. J., vol. 9, no. 2, Apr. 2017, Art. no. 2400110.

Objective: To evaluate the current state of research and areas of interest for traditional Chinese medicine (TCM) in the field of colorectal cancer treatment. Methods: Related papers published between January 1, 2012, and November 27, 2021, were found using the Web of Science Core Collection Science Citation Index Expanded. Using CiteSpace's network map generation capability, we then determined the top writers, organizations, countries, keywords, co-cited writers, journals, references, and research trends. Results: This investigation yielded a total of 336 relevant papers. China is the most productive country. Shanghai University of Traditional Chinese Medicine is the leading institution. The journal with the most popularity and publishing volume is Evidence-based Complementary and Alternative Medicine. The author with the most citations and centrality is Lin JM. The terms "epithelial-mesenchymal transition," "cell cycle arrest," "apoptosis," and "autophagy" are highly frequent and have a high betweenness centrality. Conclusion: According to the results, research on natural products, traditional Chinese medicine (TCM) extracts, and the molecular mechanisms of TCM chemical constituents constitutes the primary focus within TCM cancer treatment investigations. In recent years, there has been a surge of interest in exploring the role of gut microbiota in TCM chemical constituents research, particularly in its ability to induce apoptosis and autophagy in tumor cells, thereby suppressing tumor cell proliferation, metastasis, and invasion. However, due to the intricate composition of TCM and existing technical limitations, the underlying principles guiding TCM's efficacy in treating colorectal cancer remain unclear and warrant further investigation. [ABSTRACT FROM AUTHOR]

In this paper, we demonstrate that the superposition of two vortex beams with controlled topological charges can be realized by integrating two holographic plates with blazed grating. First, the holographic plate with blazed grating was designed and fabricated by laser direct writing for generating well-separated vortex beam. Then, the relationship between the periods of blazed grating and the discrete angles of vortex beams was systemically investigated. Finally, through setting the discrete angle and different revolving direction of the holographic plates, the composite forkshaped field was realized by the superposition of two vortex beams in a particular position. The topological charges of composite fork-shaped field (l=1, 0, 3, and 4) depend on the topological charges of compositional vortex beams, which are well agreed with the theoretical simulation. The method opens up a wide range of opportunities and possibilities for applying in optical communication, optical manipulations, and photonic integrated circuits. [ABSTRACT FROM AUTHOR]

In this letter, we report an improved algorithm to produce accurate phase patterns for generating highly uniform diffraction-limited multifocal arrays in a large numerical aperture objective system. It is shown that based on the original diffraction integral, the uniformity of the diffraction-limited focal arrays can be improved from ∼75% to >97%, owing to the critical consideration of the aperture function and apodization effect associated with a large numerical aperture objective. The experimental results, e.g., 3×3 arrays of square and triangle, seven microlens arrays with high uniformity, further verify the advantage of the improved algorithm. This algorithm enables the laser parallel processing technology to realize uniform microstructures and functional devices in the microfabrication system with a large numerical aperture objective. [ABSTRACT FROM AUTHOR]

This paper presents an innovative architecture for the active quasi-circulator to break the structural limitation on the leakage suppression. A practical prototype is implemented at K-band and fabricated by using standard 0.18-μm 1P6M CMOS technology. The comparisons between simulations and on-wafer measurements are reported in detail to confirm the feasibility and capability of the proposed active quasi-circulator. At 24 GHz, the prototype has dual transmission gains of 22.4 and 12.3 dB in the transmitting and receiving paths, respectively. The measured isolation, which is defined by the ratio of the forward transmission to reverse transmission coefficient in the same path, is higher than 50.0 dB at 24.0 GHz. By comparing the leakage phenomena between the prototype with and without feedforward cancellations, the leakage suppression can be improved with a maximum value of 44.7 dB at 23.63 GHz. [ABSTRACT FROM AUTHOR]

A miniaturized quadrature hybrid coupler, a rat-race coupler, and a 4 × 4 Butler matrix based on a newly proposed' planar artificial transmission line are presented in this paper for application in ultra-high-frequency (UHF) radio-frequency identification (RFID) systems. This planar artificial transmission line is composed of microstrip quasi-lumped elements and their discontinuities and is capable of synthesizing microstrip lines with various characteristic impedances and electrical lengths. At the center frequency of the UHF RFID system, the occupied sizes of the proposed quadrature hybrid and rat-race couplers are merely 27% and 9% of those of the conventional designs. The miniaturized couplers demonstrate well-behaved wideband responses with no spurious harmonics up to two octaves. The measured results reveal excellent agreement with the simulations. Additionally, a 4 × 4 Butler matrix, which may occupy a large amount of circuit area in conventional designs, has been successfully miniaturized with the help of the proposed artificial transmission line. The circuit size of the Butler matrix is merely 21% of that of a conventional design. The experimental results show that the proposed Butler matrix features good phase control, nearly equal power splitting, and compact size and is therefore applicable to the reader modules in various RFID systems. [ABSTRACT FROM AUTHOR]