Joint Beamforming Design for RIS-Assisted Integrated Satellite-HAP-Terrestrial Networks Using Deep Reinforcement Learning.

In this paper, we consider reconfigurable intelligent surface (RIS)-assisted integrated satellite high-altitude platform terrestrial networks (IS-HAP-TNs) that can improve network performance by exploiting the HAP stability and RIS reflection. Specifically, the reflector RIS is installed on the side of HAP to reflect signals from the multiple ground user equipment (UE) to the satellite. To aim at maximizing the system sum rate, we jointly optimize the transmit beamforming matrix at the ground UEs and RIS phase shift matrix. Due to the limitation of the unit modulus of the RIS reflective elements constraint, the combinatorial optimization problem is difficult to tackle effectively by traditional solving methods. Based on this, this paper studies the deep reinforcement learning (DRL) algorithm to achieve online decision making for this joint optimization problem. In addition, it is verified through simulation experiments that the proposed DRL algorithm outperforms the standard scheme in terms of system performance, execution time, and computing speed, making real-time decision making truly feasible.

Covert Performance for Integrated Satellite Multiple Terrestrial Relay Networks with Partial Relay Selection.

Integrated satellite multiple terrestrial relay network (ISMTRN) is a new network architecture that combines satellite communication with terrestrial communication. It both utilizes the advantages of the two systems and overcomes their shortcomings. However, security issues inevitably arise in the ISMTRN resulting from the broad coverage of the satellite beams and the openness of wireless communication. One of the promising methods to achieve secure transmission is covert communication technology, which has been a hot discussion topic in recent years. In this paper, we investigate the performance of covert communication in the ISMTRN with partial relay selection. Particularly, when the satellite transmits its signal to the user, we consider the scenario that the selected relay opportunistically sends covert information to the destination. Furthermore, the closed-form error detection probability and average covert communication rate are derived. Finally, numerical simulation results are provided to reveal the impact of critical parameters on system covert performance.

Ergodic Capacity of NOMA-Based Multi-Antenna LMS Systems with Imperfect Limitations.

With the rapid development of land mobile satellite (LMS) systems, large scale sensors and devices are willing to request wireless services, which is a challenge to the quality of service requirement and spectrum resources utilization on onboard LMS systems. Under this situation, the non-orthogonal multiple access (NOMA) is regarded as a promising technology for improving spectrum efficiency of LMS systems. In this paper, we analyze the ergodic capacity (EC) of NOMA-based multi-antenna LMS systems in the presence of imperfect limitations, i.e., channel estimation errors, imperfect successive interference cancellation, and co-channel interference. By considering multiple antennas at the satellite and terrestrial sensor users, the closed-form expression for EC of the NOMA-based LMS systems with imperfect limitations is obtained. Monte Carlo simulations are provided to verify theoretical results and reveal the influence of key parameters on system performance.

Paeonol inhibits human lung cancer cell viability and metastasis in vitro via miR-126-5p/ZEB2 axis.

Paeonol exerted an effect in lung cancer, but the underlying mechanism remained vague. In this research, we assessed the effects of Paeonol and microRNA (miR)-126-5p on the viability, migration, invasion, and epithelial-mesenchymal transition (EMT) of lung cancer cells. Lung cancer cells and BEAS-2B cells were treated with Paeonol, and viability was detected by 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di- phenytetrazoliumromide (MTT) assay. The migration and invasion of lung cancer cells after treatment with Paeonol at 40 µg/mL or 80 µg/mL were detected by wound healing assay and Transwell assay, respectively. The effects of Paeonol on transforming growth factor-ß1 (TGF-ß1)-induced EMT and relative expressions of EMT-related proteins were determined using Western blot. The target gene of miR-126-5p and the binding sites between them were predicted by TargetScan, and confirmed using dual-luciferase reporter assay. Relative expressions of miR-126-5p, its target gene and EMT-related proteins were determined by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot. Rescue assay was performed to analyze the relation between Paeonol and miR-126-5p. Paeonol down-regulated cell viability and inhibited migration, invasion and TGF-ß1-induced EMT while up-regulating miR-126-5p expression in lung cancer cells as the dose increased. However, miR-126-5p inhibitor could reverse the effect of Paeonol. ZEB2 was the target gene of miR-126-5p, and silencing ZEB2 expression reversed the effects of miR-126-5p downregulation. Paeonol also regulated the expression of ZEB2 in lung cancer cells, and this regulation depends on the regulation of miR-126-5p. Paeonol inhibits human lung cancer cell viability and metastasis via the miR-126-5p/ZEB2 axis, and could be adopted as a potential agent for lung cancer treatment.

GAN-Based Differential Private Image Privacy Protection Framework for the Internet of Multimedia Things.

With the development of the Internet of Multimedia Things (IoMT), an increasing amount of image data is collected by various multimedia devices, such as smartphones, cameras, and drones. This massive number of images are widely used in each field of IoMT, which presents substantial challenges for privacy preservation. In this paper, we propose a new image privacy protection framework in an effort to protect the sensitive personal information contained in images collected by IoMT devices. We aim to use deep neural network techniques to identify the privacy-sensitive content in images, and then protect it with the synthetic content generated by generative adversarial networks (GANs) with differential privacy (DP). Our experiment results show that the proposed framework can effectively protect users' privacy while maintaining image utility.

Is the Lesser Khingan Suitable for the Amur Tiger Restoration? Perspectives with the Current State of the Habitat and Prey Base.

The Amur tiger (Panthera tigris) has a status of being endangered on the world's IUCN red list. The northwestern part of its range is situated in Russia and China, where tigers were exterminated by humans in the 1950-1970s. To restore tiger population within a historical range, an estimation of the habitat suitability is firstly needed. The Lesser Khingan mountains (Heilongjiang) was analyzed. Habitat types were mapped by satellite images analysis and field proven. The potential habitats of the main tiger's prey species (wild boar (Sus scrofa), roe deer (Capreolus pygargus), and red deer (Cervus elaphus xanthopygus) were also assessed. Maximum entropy and linear discriminant analysis methods were applied and compared for species distribution modeling (SDM). Species distribution maps were used to design an ecological network. The fragmentation of habitat patches was evaluated by spatial ecological metrics. The habitat patches with the best metrics were assigned as cores for the ecological network, which were connected by calculated corridors. The least cost distance method (based on distance to roads and settlements) was used. The recovery of the Amur tiger in habitats of China's Lesser Khingan is shown to be possible. Types of habitats were calculated as natural corridors for moving tigers. They are mainly located at the forests' edges and characterized with various canopy structures and high variability in the tree species composition. Three potential transboundary corridors are described: (a) foothills and low mountains of the northern Lesser Khingan; (b) connection between the southeast Lesser Khingan and the western part of the Wandashan mountain system; and (c) corridor within foothills and low mountains of the eastern part of Lesser Khingan. It is recommended to establish protected areas for the important tiger core habitats, and the main optimal ways for their migrations are described during the current investigation. Moreover, it is necessary to implement habitat recovery activities for key areas.

Characterization of the complete chloroplast genome of Xanthium sibiricum, one of the traditional Chinese medicines in China.

Xanthium sibiricum is a common and annual the Traditional Chinese Medicine for many years in China. In this study, we presented the complete chloroplast genome of X. sibiricum. The chloroplast genome size was 151,897 bp in length that contained a large single-copy region (LSC) of 83,847 bp, a small single-copy region (SSC) of 17,890 bp and two inverted repeat regions (IR) of 25,080 bp. The overall nucleotide composition of the chloroplast genome is: 31.2% of A, 31.3% T, 18.5% C and 19.0% G, with a total G + C content of the chloroplast genome 37.5% and A + T of 62.5%. The chloroplast genome of X. sibiricum contains 133 genes, which included 88 protein-coding genes (PCG), 37 transfer RNA (tRNAs), and 8 ribosome RNA (rRNAs). Phylogenetic neighbour-joining (NJ) analysis result shown that the position of X. sibiricum closely related to X. strumarium in evolutionary relationship.

Influential factors on cognitive performance in middle-aged cohort: Third National Health and Nutrition Examination Survey-based study.

Aging-associated cognitive decline is closely linked to illness, dementia, increased mortality, and is a major health and social issue. The purpose of this study was to determine modifiable factors associated with cognitive performance.We analyzed data from a random sample of participants of the Third National Health and Nutrition Examination Survey, which is a cross-sectional survey, of the US population, aged 20 to 59 years, who underwent computer-based neurocognitive testing. There were 5 outcome measures in 3 neurocognitive tests: the mean of simple reaction time test, the mean total latency of the symbol digit substitution test (SDST), the average number of errors of the SDST, the average trials to criterion of the serial digit learning test (SDLT), and the average total score of the SDLT.Socioeconomic status, including older age, black ethnicity, lower income ratio, and lower education level, were associated with poorer neurocognitive function in all analyzed tests. In addition, participants with poor health, nonsmokers, and nondrinkers performed worse in all administered tests compared with individuals with good health, smokers, and participants consuming alcoholic beverages. Dietary and biochemical characteristics of the blood were not consistently associated with neurocognitive performance.Our results indicate that socioeconomic factors, health-related and dietary habits, biochemical parameters of the blood, and job category were associated with neurocognitive performance in visual attention, learning, and concentration in a large, nationally representative sample of healthy, ethnically diverse 20 to 59-year-olds. Future studies are needed to understand the mechanisms of cognitive aging and the factors that contribute to its individual differences.

Phylogenetic relationship of Wolverine Gulo gulo in Mustelidae revealed by complete mitochondrial genome.

The Wolverine Gulo gulo is an endangered species in China. We first obtained blood sample, extracted the sample DNA and sequenced the whole mtDNA genome of wolverine in Northeast China. We built the phylogenetic tree of wolverine and 10 other most closely related Mustelidae species. The wolverine's complete mitogenome is 16 575 bp in length, includes 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes and one control region. The phylogenetic tree indicates that Wolverine is mostly close to the genus Martes.

Clinical observation on the treatment of atrial fibrillation with amiodarone combined with Shenmai Injection (参麦注射液).

OBJECTIVE: To observe the therapeutic efficacy and safety of amiodarone combined with Shenmai Injection (参麦注射液) on atrial fibrillation. METHODS: A total of 351 patients with atrial fibrillation caused by cardiovascular diseases and idiopathic atrial fibrillation were assigned to amiodarone group (control group, 128 cases) and amiodarone combined with Shenmai Injection group (treatment group, 223 cases). The patients in the control group received intravenous injection of 150 mg amiodarone in 10 min, followed by intravenous drip infusion at 1 mg /min and 6 h later at 0.5 mg /min until 48 h or cardioversion. The patients in the treatment group received the same treatment of amiodarone, while in addition, they received an injection of Shenmai Injection of 100 mL simultaneously. Blood pressure, ventricular rate, and cardioversion were observed. RESULTS: The total efficiency rate was 98% (control group) and 99% (treatment group) (P>0.05). The mean ventricular rate decreased 23% and 31% in the control group and the treatment group, respectively (P<0.05). The mean cardioversion time of the two groups was 570±211 min and 351±123 min, respectively (P<0.05). Only mild side effects were observed in both groups. CONCLUSION: Compared with amiodarone, amiodarone combined with Shenmai Injection takes effect more quickly with low side effects on the treatment of atrial fibrillation.