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This study aimed to investigate whether analgesia nociception index (ANI) could be an indicator of perioperative pain during laparoscopic trocar insertion.

This study aimed to reveal the flavor quality changes of live oysters during different steps of circulation, and optimize the management of live oyster transportation in order to improve the survival quality of oysters. The changes in the types and contents of volatile flavor compounds in Crassostrea gigas sequentially subjected to depuration, induced dormancy and simulated waterless live transportation were investigated using solid phase microextraction coupled to gas chromatography-mass spectrometry (SPME-GC-MS). Results showed that a total of 49 volatile flavor substances were identified in live C. gigas, including aldehydes, ketones, esters, hydrocarbons, alcohols, nitrogen-containing and sulfur-containing heterocyclic compounds. Post-harvest stress had a significant impact on the flavor quality. The content of pleasant flavor compounds was significantly enhanced while the content of irritating odor substances was evidently reduced, and lipid oxidation was significantly alleviated after 24 h of depuration. Lipid oxidation in oysters was increased with waterless live transportation time, and the total amount of volatile flavor substances was slowly accumulated. Odor activity values (OAVs) showed that heptanal, nonanal, (E)-2-nonenal, 4-ethylbenzaldehyde, hexanal, (E)-2-octenal, undecanal, (E)-2-decenal, decanal, (E,E)-2,4-nonadienal and 2-pentyl furan were the key flavor substances of live C. gigas, which could be used as a reference to reflect the physiological status of live oysters. Principal component analysis (PCA) showed that the cumulative contribution of the first three principal components to total variances was 85.6%, allowing a clear distinction between the different stages of circulation. In conclusion, the vitality and flavor substances of C. gigas reach a new level after post-harvest depuration for 24 h, which is more conducive to long-term low temperature and waterless live oyster preservation. Meanwhile, the analysis of volatile components can be used as a method to identify the vitality during the circulation of live shellfish.

Simple Summary: As a fish under second-class protection in China, the structure and characteristics of the mitochondrial genome Procypris mera (Lin, 1933) have not been reported. We reported three mitochondrial genomes of P. mera from three sites and conducted a detailed analysis of their characteristics, which were employed to infer phylogenetic relationships. These findings revealed that the mitochondrial genomes of P. mera from the different sites exhibited considerable similarity. Furthermore, the phylogenetic tree constructed from amino acid sequences supported the original phylogenetic relationships of the subfamily Cyprininae in China, suggesting that the genus Puntioplites is sister to all other genera of the subfamily Cyprinidae of China; the genus Procypris forms a monophyletic group; and the genera Carassioides, Carassius, and Cyprinus form a monophyletic group. Procypris mera (Lin, 1933), also known as the Chinese ink carp, currently has a second-class protection status in China. Understanding the structure and characteristics of mitochondrial genes provides essential information for resource conservation and phylogenetic studies of P. mera. Here, we sequenced the mitochondrial genomes of three P. mera (WYL1-3) from three sites and performed phylogenetic analysis. The generated three genomes were 16,587 bp in length, comprising 13 protein-coding genes (PCGs), 22 tRNAs, two rRNAs, and two non-coding regions (control region (CR), D-loop, and light-stranded replication start OL), with a preference for codons ending in A or C. The mitochondrial genomes of WYL2 and WYL3 were identical, differing from that of WYL1 by only five single-nucleotide polymorphisms (SNPs). All mitochondrial PCGs had Ka/Ks ratios of less than one, suggesting purifying selection. Phylogenetic tree analysis based on amino acid sequences suggested that the genus Puntioplites is sister to all other genera of the subfamily Cyprinidae of China; the genus Procypris forms a monophyletic group; and the genera Carassioides, Carassius, and Cyprinus form a monophyletic group. This study contributes to our understanding of the phylogenetic relationships in subfamily Cyprininae in China and lays the foundation for resource conservation and management of P. mera. [ABSTRACT FROM AUTHOR]

This study investigates the potential use of Yellow River sand (YRS) sourced from the lower reaches of the Yellow River in China as a sustainable and cost-effective substitute for quartz sand in Engineered Cementitious Composites (ECC). With an annual accumulation of approximately 400 million tons in this region, YRS presents a substantial resource. ECC specimens with 100% YRS replacement with quartz sand were subjected to various curing methods: natural, steam, standard, and sprinkler. Extensive mechanical testing including flexural, compressive, uniaxial tensile, and four-point flexural tests was conducted. Additionally, Scanning Electron Microscope (SEM) and Mercury Intrusion Porosimetry (MIP) analyses investigated microscopic mechanisms influencing macroscopic mechanical properties. Finally, the mechanical properties of the YRS-ECC test block after 14 days of standard curing and the traditional sand ECC test block were compared and analyzed. The results indicate that ECC specimens with 100% YRS substitution under natural curing show an optimal ultimate tensile strain of more than 4%, providing the best resistance to the reduction in ultimate flexural load and deflection due to aging. Steam curing enhances flexural and compressive strength, achieving an ultimate flexural load of 5 kN and a maximum deflection of 4.42 mm at 90 days. SEM analysis revealed lower C-S-H gel density under natural curing and higher under steam curing, enhancing fiber pull-out in steam-cured specimens. The MIP tests demonstrated that natural curing had the highest porosity (32.86%) and average pore size (51.69 nm), whereas steam curing resulted in the smallest average pore size, with 44% of pores under 50 nm. Compared with traditional sand, it is found that the ultimate bending load and deflection of YRS-ECC are 5.7% and 9.4% higher than those of traditional sand ECC, respectively, and its ultimate tensile strength and strain are also improved. These findings highlight YRS as a sustainable alternative to natural sand in ECC, with natural curing proving the most effective for superior mechanical performance, including tensile strain, crack resistance, and durability. [ABSTRACT FROM AUTHOR]

This study proposes an ultra-wideband radar cross section (RCS) reduction technique based on reflection phase interference cancellation and tunable absorption. The operational frequency band of the combined structure is enhanced by uniting two overlapped frequency ranges effectively. As proof of concept, a demonstration structure is designed with a stacked chessboard and an active frequency selective surface (AFSS) absorber. The upper chessboard constructed of a square loop and circular patch unit cells can realize destructive phase interference performance at higher frequencies, while the bottom AFSS absorber achieves tunable absorption at a lower frequency range. Three-dimensional scattering patterns at low and high frequencies are analyzed to verify these two different RCS reduction mechanisms. The combined fabrication structure can obtain an ultra-wideband RCS reduction of more than 10 dB from 4.4 to 36.5 GHz, compared to a metallic plate of the same size, indicating good agreement between full-wave simulation and measurements. [ABSTRACT FROM AUTHOR]

Objectives Aiming to resolve the adverse effects of frequency selective surface (FSS) radomes on array antenna beam scanning, a method for optimizing FSS radomes is proposed.Methods First, an array antenna with 25 half-wave dipole elements is designed. At the same time, a wideband Jerusalem structure is designed as a frequency selection unit with the goal of bandwidth matching and stable filtering performance at high angle incidence. On this basis, HFSS software is used to optimize the distance between the FSS radome and array antenna with the lowest gain on the side lobes and back lobes. Finally, the size of the FSS radome is determined by the beam width and scanning angle of the array antenna, and the scanning angle error of a separate array antenna is compared with an FSS radome-array antenna system. In order to verify the accuracy of the theory, the array antenna pattern is tested with the FSS radome at different scanning angles. Results The results show that when the distance of FSS radome between array antenna is 0.5λ, the influence of FSS radome on the secondary and rear lobe gains of the array antenna is minima；when the scanning angle is up to 40°, the FSS radome produces an error of about 0.25° to the array antenna scanning angle.Conclusions The FSS radome designed by the appropriate method has little effect on the beam scanning direction of the array antenna. This method can also be used in the design of larger array antennas and FSS radomes.

[Objectives] This paper studies the development of a microstrip antenna with both traditional radiation characteristic and good out-of-band rejection characteristic.[Methods] Through the filter integrated design method,the microstrip antenna with filtering characteristic,composed of a microstrip antenna,a coupled line,and two resonators is designed. In addition to the capability of meeting the traditional antenna design requirements,the microstrip antenna shall have the external quality factor that is equal to the external quality factor of the last resonator of the band-pass filter,thus enabling it to still function as a filter after being used as a substitute of the last resonator of the filter;in the filter design,the coupled line acts as an admittance converter to realize the energy coupling between the filter resonator and the microstrip antenna.[Results] The simulation results show that as the impedance bandwidth is 2.37-2.53 GHz,the gain variation within the impedance bandwidth is gentle,the maximum in-band gain deviation is about 0.5 dB,the maximum gain is 7.5 dB,and the gain at 100 MHz outside the passband is rapidly reduced to -10 dBi, the microstrip antenna has good out-of-band rejection characteristic.[Conclusions] The microstrip antenna with filtering characteristic designed in the paper reduces the overall size of filter and antenna and the transmission loss between the filter and the antenna,and can be used in modern communication systems.