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Abstract The Indo-Pacific king mackerel, scientifically known as Scomberomorus guttatus, is a valued marine species that holds significant commercial importance in the Indo-Pacific region. However, the lack of genomic resources has hindered a comprehensive understanding of this species. In this study, we constructed a genome of Indo-Pacific king mackerel at the chromosome level using a combination of PacBio HiFi reads and a chromosome contact map (Hi-C). The resulting genome had high contig and scaffold N50 values of 8.84 Mb and 32.9 Mb, respectively. In the genome assembly, which is 797.66 Mb in size and consists of 24 chromosomes, we also identified 35.89% repetitive elements and predicted 25,886 protein-coding genes. Our study not only benefits to reveal the possible mechanism of adaptive evolution in this fish, but also offers insight for the future sustainable management of these valuable biological resources.

Abstract Pharmacologically-induced persistent hippocampal γ oscillation in area CA3 requires activation of α-Amino-3-hydroxy-5-methyl-4-isoxazolepropionate receptors (AMPARs). However, we demonstrated that exogenous AMPA dose-dependently inhibited carbachol (CCH)-induced γ oscillation in the CA3 area of rat hippocampal slices, but the underlying mechanism is not clear. Application of AMPARs antagonist NBQX (1 μM) did not affect γ oscillation power (γ power), nor AMPA-mediated γ power reduction. At 3 μM, NBQX had no effect on γ power but largely blocked AMPA-mediated γ power reduction. Ca2+-permeable AMPA receptor (CP-AMPAR) antagonist IEM1460 or CaMKK inhibitor STO-609 but not CaMKIIα inhibitor KN93 enhanced γ power, indicating that activation of CP-AMPAR or CaMKK negatively modulated CCH-induced γ oscillation. Either CP-AMPAR antagonist or CaMKK inhibitor alone did not affected AMPA-mediated γ power reduction, but co-administration of IEM1460 and NBQX (1 μM) largely prevented AMPA-mediated downregulation of γ suggesting that CP-AMPARs and CI-AMPARs are involved in AMPA downregulation of γ oscillation. The recurrent excitation recorded at CA3 stratum pyramidale was significantly reduced by AMPA application. Our results indicate that AMPA downregulation of γ oscillation may be related to the reduced recurrent excitation within CA3 local neuronal network due to rapid CI-AMPAR and CP-AMPAR activation.

Summary: Warm ambient conditions induce thermomorphogenesis and affect plant growth and development. However, the chromatin regulatory mechanisms involved in thermomorphogenesis remain largely obscure. In this study, we show that the histone methylation readers MORF-related gene 1 and 2 (MRG1/2) are required to promote hypocotyl elongation in response to warm ambient conditions. A transcriptome sequencing analysis indicates that MRG1/2 and phytochrome interacting factor 4 (PIF4) coactivate a number of thermoresponsive genes, including YUCCA8, which encodes a rate-limiting enzyme in the auxin biosynthesis pathway. Additionally, MRG2 physically interacts with PIF4 to bind to thermoresponsive genes and enhances the H4K5 acetylation of the chromatin of target genes in a PIF4-dependent manner. Furthermore, MRG2 competes with phyB for binding to PIF4 and stabilizes PIF4 in planta. Our study indicates that MRG1/2 activate thermoresponsive genes by inducing histone acetylation and stabilizing PIF4 in Arabidopsis.

The commercialization of GaN-based Schottky barrier diodes in middle- and high- voltage applications still faces many challenges, in which the lack of an effective selective area p-type doping method is one of the main obstacles. This paper proposes novel vertical GaN-based Schottky diodes with trench MIS structure and an embedded p-GaN protection layer (junction-trench MIS barrier Schottky diodes, J-TMBS). The trench structure and lateral p-n junctions can be achieved by selectively etching the very thin p-GaN and then regrowing n-GaN. Therefore, the fabrication technology avoids the selective area p-type doping process, and the dry etching damage and poor sidewall regrowth interface issue, which are serious in GaN Merged pn/Schottky (MPS) diodes, can also be alleviated for the proposed J-TMBS. Compared with the optimized GaN trench MIS barrier Schottky (TMBS) diodes, the surge current capability and dielectric reliability of the proposed J-TMBS are significantly improved (the electric field of the dielectric layer and maximum lattice temperature under the surge test can be reduced by 448% and 202%, respectively). In addition, the specific on-resistance (Ron,sp) and breakdown voltage remain basically unchanged compared with TMBS. Compared with the optimized GaN MPS diodes, the proposed structure improves the specific on-resistance by 17.2% benefiting from the reduced area of the JFET region without degrading the reverse I–V characteristics and surge current capability. The proposed J-TMBS exhibits potential in practical high voltage (>600 V) application of GaN Schottky power diodes.

The gut microbiome is a unique marker for cetaceans’ health status, and the microbiome composition of their skin wounds can indicate a potential infection from their habitat. Our study provides the first comparative analysis of the microbial communities from gut regions and skin wounds of an individual Indo-Pacific finless porpoise (Neophocaena phocaenoides). Microbial richness increased from the foregut to the hindgut with variation in the composition of microbes. Fusobacteria (67.51% ± 5.10%), Firmicutes (22.00% ± 2.60%), and Proteobacteria (10.47% ± 5.49%) were the dominant phyla in the gastrointestinal tract, while Proteobacteria (76.11% ± 0.54%), Firmicutes (22.00% ± 2.60%), and Bacteroidetes (10.13% ± 0.49%) were the dominant phyla in the skin wounds. The genera Photobacterium, Actinobacillus, Vibrio, Erysipelothrix, Tenacibaculum, and Psychrobacter, considered potential pathogens for mammals, were identified in the gut and skin wounds of the stranded Indo-Pacific finless porpoise. A comparison of the gut microbiome in the Indo-Pacific finless porpoise and other cetaceans revealed a possible species-specific gut microbiome in the Indo-Pacific finless porpoise. There was a significant difference between the skin wound microbiomes in terrestrial and marine mammals, probably due to habitat-specific differences. Our results show potential species specificity in the microbiome structure and a potential threat posed by environmental pathogens to cetaceans.

Due to the non-spherical perturbation of the Moon, the lifetime of ultra low-altitude Lunar spacecraft may be quite short. In this paper, we analyze the lifetime of about 50 km-altitude Lunar spacecraft with different initial orbit. The lifetime in low inclination orbits is much shorter than the ones in the near polar orbits. To extend the lifetime and keep the spacecraft in an appropriate range, an orbit maintenance strategy based on low-thrust propulsion system is proposed. The influence of the orbit initial conditions (e.g., semi-major axis, inclination, right ascension of the ascending node) on lifetime extension are discussed and the effect of the low-thrust magnitude in orbit maintenance is analyzed. According to the numerical simulation results, the lifetime of about 50 km-altitude 100 kg Lunar spacecraft with 10 kg fuel and 20 mN thruster can be extended from 7.958 days to over a 109.1725 days, which demonstrates the effectiveness of the strategy. Furthermore, a global perspective for ultra low-altitude Lunar spacecraft lifetime extension problem is provided in this paper, which can be applied to Moon mission designs extensively.

We propose two approaches based on feedforward control and model-predictive control, respectively, to solve the station-keeping problem of an electric-propulsion geostationary Earth orbit (GEO) satellite, whose thrusters are mounted on two robotic arms on its anti-nadir face. This novel configuration enables a wider range of thrust direction, making it possible to regard the thrust direction as control variables. To solve this control problem, we present the quick feedforward controller (QFFC) and the fuel-optimal model predictive controller (FOMPC). The QFFC is developed based on the analysis of GEO dynamics and the thruster configuration. The FOMPC applies an optimization algorithm to solve the nonlinear model predictive control (NLMPC) problem with the initial value given by the QFFC. Numerical simulations suggest that both controllers could achieve stable station-keeping over multiple objective elements with fewer thrusters and fewer maneuvers. The QFFC has higher control accuracy and lower computational requirements than the FOMPC, whereas the FOMPC could significantly save fuel consumption. The robustness assessment and other discussions of the controllers are also presented.

This paper investigates the price and service rate decisions in a customer-intensive service in an M/M/1 queue system under the influence of social interactions, where a higher value of the service is perceived if more customers purchase the service. The customer-intensive nature of the service requires a low service speed to maintain its quality, which may increase the congestion of the system. Two cases where customers are either homogeneous or heterogeneous in terms of the customer intensity are considered. It is found that social interactions can always benefit the service provider as more expected revenue can be achieved, and potential profits would be lost if the influence of social interactions is ignored. For the case with heterogeneous customers, the optimal price and service rate decisions are solved with or without considering social interaction effect. The study finds the proportions of high and low sensitive customers and the social interaction intensity are critical to the operational decisions and the market coverage strategies. These results offer a better understanding on the interplay between the quality-speed conundrum and the influence of social interactions in customers’ purchase behaviour in managing customer-intensive services.

Background/purpose: Inducing human-periodontal-ligament-stem-cell (hPDLSC) differentiation by DNA transfection is a promising way for periodontal tissue engineering. However, there are only a few studies that focus on the introduction of foreign DNA into hPDLSCs by nonviral methods that are relatively safe. Hence, the major purposes of this study were to compare the transfection efficiency and toxicity of nonviral-gene-transfer methods on hPDLSCs, and to search for the best approach and optimal protocol for transferring genes into hPDLSCs using nonviral vectors. Materials and methods: The hPDLSCs were transfected by (1) Lipofectamine 2000, (2) polyethylenimine, (3) GBfectene-Elite transfection reagent, (4) X-tremeGENE HP DNA Transfection Reagent, and (5) Magnet-Assisted Transfection (MATra), compared to (6) lentiviral vectors harboring a green-fluorescent-protein gene. The transfection efficiency was measured by a fluorescence microscope and flow cytometry. Meanwhile, the cell morphology and growth status were observed to estimate the cytotoxicity. Results: Among these methods, the transfection efficiency of the former four methods was not very satisfactory (< 6%) compared to that of lentiviral vectors (positive control, 95%). However, MATra was the most effective nonviral method (11%). Moreover, the cellular toxicity was lower than that of the former four methods. Conclusion: The transfection efficiency of hPDLSCs with MATra was higher than the other nonviral transfection reagents in this study, but it was far less than the viral vectors. Saving from the interaction between the positive and negative charges, and increasing the opportunity of contact between the plasmid and the cytomembrane might be the key to enhancing the transfection efficiency for hPDLSCs in application of periodontal tissue engineering.

Background/purpose: Periodontitis is related to diabetes mellitus. However, whether periodontal therapy can affect glycemic control remains unclear. This study aims to evaluate the effects of scaling and root planing (SRP) as well as enhanced root planing (ERP) on the glycemic control and periodontal condition of patients with type 2 diabetes mellitus (T2DM) and chronic periodontitis. Materials and methods: Patients with T2DM and chronic periodontitis were randomly assigned to treatment (n = 49) and control (n = 22) groups. The treatment group was treated with SRP, whereas the control group remained untreated. After 3 months, the patients in the treatment group were randomly divided into sub-ERP (n = 25) and subprophylaxis (n = 24) groups, which were treated with ERP and prophylaxis, respectively. Results: Hemoglobin A1c and fast plasma glucose levels in the treatment group decreased after SRP treatment. The changes in the hemoglobin A1c level in this group was significantly greater than that in the control group (P

This paper investigates the design optimization of an electrostatically actuated microcantilever resonator that operates in air. The nonlinear effects of electrostatic actuation and air damping make the structural dynamics modeling more complex. There is a need for an efficient way to simulate the system behavior so that the design can be more readily optimized. This paper describes an efficient analytical approach for determining the optimum design for a microcantilever resonant mass sensor. One simple case is described. The sensor design is a square plate that is coated with a functional polymer and attached to the substrate with folded leg springs. The plate has a square hole in the middle to reduce the effect of squeeze film damping. With the analytical approach, the optimum hole size for maximum sensitivity is found.

Introduction: Whole-genome duplication (WGD) is one of the most sudden and dramatic events rarely reported in invertebrates, but its occurrence can lead to physiological, morphological, and behavioral diversification. WGD has also never been reported in barnacles, which is one of the most unique groups of crustaceans with extremely speciallized morphology (calcareous shells) and habits (intertidal sessile lifestyle). Objectives: To investigate whether WGD has occurred in barnacles and examine its potential role in driving the adaptive evolution and diversification of barnacles. Methods: Based on a newly sequenced and assembled chromosome-level barnacle genome, a novel WGD event has been identified in barnacles through a comprehensive analysis of interchromosomal synteny, the Hox gene cluster, and synonymous substitution distribution. Results: We provide ample evidences for WGD in the barnacle genomes. Comparative genomic analysis indicates that this WGD event predates the divergence of Thoracicalcarea, occurring more than 247 million years ago. The retained ohnologs from the WGD are primarily enriched in various pathways related to environmental information processing, shedding light on the adaptive evolution and diversification of intertidal sessile lifestyle. In addition, transcriptomic analyses show that most of these ohnologs were differentially expressed following the ebb of tide. And the cytochrome P450 ohnologs with differential expression patterns are subject to subfunctionalization and/or neofunctionalization for intertidal adaptation. Besides WGD, parallel evolution underlying intertidal adaptation has also occurred in barnacles. Conclusion: This study revealed an ancient WGD event in the barnacle genomes, which is potentially associated with the origin and diversification of thoracican barnacles, and may have contributed to the adaptive evolution of their intertidal sessile lifestyle.