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Supporting seamless global coverage, satellite Internet is an important expansion and extension of terrestrial communication systems, plays a key role in the space–air–ground integrated network, and acts as an important information infrastructure for building China's strength in cyberspace. Developing satellite Internet is of great strategic significance, and corresponding research on its resource management and scheduling is urgently needed. This study illustrates the fundamental concepts and international development frontiers of satellite Internet as well as the basic elements and research progress of satellite Internet resource management and scheduling, identifies the challenges imposed by the new environment and new modes of satellite Internet, and proposes the development strategies. Moreover, it designs a technical route for satellite Internet resource management, including the primary stages of satellite – ground network interconnection, integration of heterogeneous resources, intelligent on-demand service, and native intelligence. In addition, this study proposes the model and architecture of satellite Internet resource management and scheduling, and constructs a key technical system involving high spatio-temporal dynamic resource characterization, multi-dimensional resource time-continuum deterministic analysis, multi-dimensional time-varying capacity pool indexing, and intelligent decision planning. To realize the intelligent and efficient management and scheduling of satellite Internet resources, we should focus on the network characteristics such as resource heterogeneity, dynamic change of network structure, and differentiated service requirements, implement satellite Internet resource management and scheduling according to the optimized technical route, achieve breakthroughs regarding corresponding key technologies, and integrate artificial intelligence technologies into the resource management and scheduling.

In addition to greater precipitation on extreme days of precipitation, preceding and succeeding precipitation (PSP) is often an objective component of flooding in the mid–lower reaches of the Yangtze River Basin (MLRYRB). In this study, focused on the temporal distribution pattern of precipitation, the concept of an extreme precipitation event (EPE), defined as a consecutive precipitation event having at least one daily precipitation extreme, is proposed to consider PSP in an extreme event. We analyzed the spatiotemporal variation of four types of EPEs based on daily data obtained from 130 monitoring stations covering 1960–2019. Extreme precipitation increased significantly over the last 60 years (p < 0.01). The frequency and precipitation amount of single-day EPEs accounted for only 13% and 21%, respectively, while multi-day continuous EPE types that are associated with PSP accounted for 87% and 79%, respectively, confirming the connotations of EPEs. The front and late EPEs under the 100-year return level reached 250 mm and 230 mm, respectively. Furthermore, climate warming could lead to significant increases in the frequency of single-day and late EPEs, particularly in the southern region. The EPE concept may be helpful in exploring disaster-causing processes under extreme weather, and it provides a theoretical basis for deriving the precipitation hazard chain, which is more applicable to basins with long precipitation durations. [ABSTRACT FROM AUTHOR]

Microbiologically influenced corrosion (MIC) is the process of material degradation in the presence of microorganisms and their biofilms. This is an environmentally assisted type of corrosion, which is highly complex and challenging to fully understand. Different metallic materials, such as steel alloys, magnesium alloys, aluminium alloys, and titanium alloys, have been reported to have adverse effects of MIC on their applications. Though many researchers have reported bacteria as the primary culprit of microbial corrosion, several other microorganisms, including fungi, algae, archaea, and lichen, have been found to cause MIC on metal and non-metal surfaces. However, less attention is given to the MIC caused by fungi, algae, archaea, and lichens. In this review paper, the effects of different microorganisms, including bacteria, fungi, algae, archaea, and lichens, on the corrosion properties of engineering materials have been discussed in detail. This review aims to summarize all of the corrosive microorganisms that directly or indirectly cause the degradation of structural materials. Accusing bacteria of every MIC case without a proper investigation of the corrosion site and an in-depth study of the biofilm and secreted metabolites can create problems in understanding the real cause of the materials' failure. To identify the real corrosion agent in any environment, it is highly important to study all kinds of microorganisms that exist in that specific environment. [ABSTRACT FROM AUTHOR]

Background: Drug discovery processes, such as new drug development, drug synergy, and drug repurposing, consume significant yearly resources. Computer-aided drug discovery can effectively improve the efficiency of drug discovery. Traditional computer methods such as virtual screening and molecular docking have achieved many gratifying results in drug development. However, with the rapid growth of computer science, data structures have changed considerably; with more extensive and dimensional data and more significant amounts of data, traditional computer methods can no longer be applied well. Deep learning methods are based on deep neural network structures that can handle high-dimensional data very well, so they are used in current drug development. Results: This review summarized the applications of deep learning methods in drug discovery, such as drug target discovery, drug de novo design, drug recommendation, drug synergy, and drug response prediction. While applying deep learning methods to drug discovery suffers from a lack of data, transfer learning is an excellent solution to this problem. Furthermore, deep learning methods can extract deeper features and have higher predictive power than other machine learning methods. Deep learning methods have great potential in drug discovery and are expected to facilitate drug discovery development. [ABSTRACT FROM AUTHOR]

Secretion and efflux of oxalic acid from roots is an important aluminum detoxification mechanism for various plants; however, how this process is completed remains unclear. In this study, the candidate oxalate transporter gene AtOT, encoding 287 amino acids, was cloned and identified from Arabidopsis thaliana. AtOT was upregulated in response to aluminum stress at the transcriptional level, which was closely related to aluminum treatment concentration and time. The root growth of Arabidopsis was inhibited after knocking out AtOT, and this effect was amplified by aluminum stress. Yeast cells expressing AtOT enhanced oxalic acid resistance and aluminum tolerance, which was closely correlated with the secretion of oxalic acid by membrane vesicle transport. Collectively, these results underline an external exclusion mechanism of oxalate involving AtOT to enhance oxalic acid resistance and aluminum tolerance. [ABSTRACT FROM AUTHOR]

Aluminum (Al) toxicity severely restricts crop growth and productivity in acidic soils. The rubber tree is one of the most economically important crops in tropical regions, which is tolerant to high concentrations of Al in sand or hydroponic culture conditions compared with other plants that have been reported. However, the mechanisms of Al tolerance in rubber trees remain unknown. In this study, we conducted a transcriptome and metabolome analysis for rubber tree sapling roots treated with 200 mM Al for 0 (CK), 2 or 5 days, respectively. Compared with the CK, a total of 9534 differentially expressed genes (DEGs) and 3821 differentially expressed metabolites (DEMs) were identified in 2 d of Al treatment. There were 10,373 DEGs and 4636 DEMs after 5 d of Al treatment, and 1626 DEGs and 1674 DEMs between 2 and 5 d of Al treatment. The DEGs mainly concentrated in transporters, transcription factors (TFs), cell wall biosynthesis and antioxidant systems, and the DEMs were mainly focused on lipids and lipid-like molecules, organic acids and derivatives, organic oxygen compounds, phenylpropanoids and polyketides. The combined transcriptome and metabolome analysis indicated DEGs and DEMs involved in ABC transporters, glutathione metabolism, flavonoid biosynthesis and phenylalanine metabolic pathways were identified to be closely associated with the Al tolerance of rubber trees. Our study elucidated the mechanism of rubber trees' tolerance to Al at the transcriptional and metabolic levels, which provides a theoretical basis for the study of Al tolerance both for rubber trees and other woody plants. [ABSTRACT FROM AUTHOR]

Secretion of oxalic acid from roots is an important aluminum detoxification mechanism for many plants such as Hevea brasiliensis (rubber tree). However, the underlying molecular mechanism and oxalate transporter genes in plants have not yet been reported. In this study, the oxalate transporter candidate genes HbOT1 and HbOT2 from the rubber tree were cloned and preliminarily identified. It was found that HbOT1 had a full length of 1163 bp with CDS size of 792 bp, encoding 263 amino acids, and HbOT2 had a full length of 1647 bp with a CDS region length of 840 bp, encoding 279 amino acid residues. HbOT1 and HbOT2 were both stable hydrophobic proteins with transmembrane structure and SNARE_assoc domains, possibly belonging to the SNARE_assoc subfamily proteins of the SNARE superfamily. qRT-PCR assays revealed that HbOT1 and HbOT2 were constitutively expressed in different tissues, with HbOT1 highly expressed in roots, stems, barks, and latex, while HbOT2 was highly expressed in latex. In addition, the expressions of HbOT1 and HbOT2 were up-regulated in response to aluminum stress, and they were inducible by metals, such as copper and manganese. Heterologous expression of HbOT1 and HbOT2 in the yeast mutant AD12345678 enhanced the tolerance to oxalic acid and high concentration aluminum stress, which was closely correlated with the secretion of oxalic acid. This study is the first report on oxalate transporter genes in plants, which provides a theoretical reference for the study on the molecular mechanism of oxalic acid secretion to relieve aluminum toxicity and on aluminum-tolerance genetic engineering breeding. [ABSTRACT FROM AUTHOR]

Medicinal and food homology materials are a group of drugs in herbal medicine that have nutritional value and can be used as functional food, with great potential for development and application. Flavonoids are one of the major groups of components in pharmaceutical and food materials that have been found to possess a variety of biological activities and pharmacological effects. More and more analytical techniques are being used in the study of flavonoid components of medicinal and food homology materials. Compared to traditional analytical methods, spectroscopic analysis has the advantages of being rapid, economical and free of chemical waste. It is therefore widely used for the identification and analysis of herbal components. This paper reviews the application of spectroscopic techniques in the study of flavonoid components in medicinal and food homology materials, including structure determination, content determination, quality identification, interaction studies, and the corresponding chemometrics. This review may provide some reference and assistance for future studies on the flavonoid composition of other medicinal and food homology materials. [ABSTRACT FROM AUTHOR]

The kiwifruit is cultivated globally due to its diversity of phytochemicals, especially phenolic compounds, which have antioxidant, anti-inflammatory and anti-cancer medical effects. However, only the pulp of the kiwifruit is consumed, while the peels and cores—which are also rich in phytochemicals—are usually wasted. Meanwhile, detailed information on the comparison among the three parts is still limited. In this study, the antioxidant potentials in the core, pulp, and peel of the three most commercialized kiwifruit cultivars (Australian-grown Hayward kiwifruit, New Zealand-grown Zesy002 kiwifruit, and New Zealand-grown organic Hayward kiwifruit) were selected. Their antioxidant capacities were tested, and their phenolic profiles were identified and characterized by liquid chromatography-electrospray ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF-MS/MS). The antioxidant results showed that the peel of New Zealand-grown organic Hayward kiwifruit contained the highest total phenolic content (9.65 mg gallic acid equivalent (GAE) mg/g) and total antioxidant capacity (4.43 mg ascorbic acid equivalent (AAE) mg/g), respectively. In addition, the antioxidant capacity of the peel is generally higher than that of the pulp and cores in all species, especially ABTS (2,2-Azino-bis-3ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging ability), ranging from 13.25 mg AAE/g to 18.31 mg AAE/g. The LC-ESI-QTOF-MS/MS tentatively identified the phenolic compounds present in the three kiwifruit species, including 118 unique compounds in kiwifruit peel, 12 unique compounds in the kiwifruit cores, and three unique compounds in kiwifruit pulp. The comprehensive characterization of the phenolics in the kiwifruits' parts indicates the importance of their waste part as a promising source of phenolics with antioxidant properties. Therefore, this study can guide the industry with meaningful information on kiwifruit waste, and can provide it with the utilization of food and pharmacological aspects. [ABSTRACT FROM AUTHOR]

In this study, the bending behavior of novel magnesium alloy facesheet and 3D-printed polylactic acid (PLA) lattice core sandwich panels with enhanced interface adhesion has been investigated by joint experiment and simulation method. A reliable numerical model for predicting three-point bending behavior of hybrid sandwich panels was developed and an explicit finite element analysis using ABAQUS/Explicit with a self-written VUMAT user subroutine was conducted. Meanwhile, hybrid sandwich panels were evaluated experimentally by three-point bending tests in order to validate the results obtained in the FEA. The comparison results have shown that the FEA predictions are consistent with the experimental tests. The bending resistance of the hybrid PLA core/Mg alloy composite sandwich panel is better than that of the integrated PLA sandwich panel. Among the four lattice geometries studied, namely body-centered cubic (BCC), BCC with gradient distribution of struts (BCCG), BCC with vertical struts connecting all nodes (BCCV), and face and body centered cubic unit cell with vertical struts (F2BCCZ), the sandwich structure with BCCV lattice cores has the better bending bearing capacity. The core configuration and core density have a coupling effect on the bending properties and failure modes of the hybrid sandwich panels. [ABSTRACT FROM AUTHOR]

Dimethylamine (DMA) and diethylamine (DEA) as precursors for the formation of potentially N-nitrosamines are widespread in the environment, and the removal of these disinfection byproduct precursors from water is of great significance to control the quality of drinking water. In this study, a three-dimensional hierarchical NiLa-layered double hydroxide/biochar nanocomposite (NiLa-LDH/BC) was prepared to remove them from a synthetic solution and real surface water. NiLa-LDH nanoplatelets endowed the biochar with an improved porous structure, high functional groups, and more active metal sites. NiLa-LDH/BC exhibited a high DMA and DEA adsorption capacity of 46.45 and 40.10 mg g–1, which is 6.31 and 7.85 times higher than that of BC, respectively. A fixed-bed column experiment revealed that NiLa-LDH/BC could last for ∼1860 to 2400 bed volumes (BVs) before a breakthrough occurred (approximately 9 times higher than that of BC). In addition, the leaching test and regeneration and toxicity test of Daphnia magna demonstrate the high stability (over 88% adsorption capacity after seven adsorption–desorption cycles), extremely low metal leaching (<0.01 mg g–1), and low toxicity (24h-EC50 and 48h-EC50 of the NiLa-LDH/BC leachates were 13.07 and 6.33%, respectively). According to material characterization, the main removal mechanism of DMA and DEA by NiLa-LDH/BC was electrostatic attraction, hydrogen bonding, and complexation. Density functional theory calculations were also applied to evaluate the DMA and DEA adsorption performance of materials. Overall, this study indicated that three-dimensional hierarchical NiLa-LDH/BC can be promising in highly efficient removal of N-nitrosamine precursors from real surface water. [ABSTRACT FROM AUTHOR]

P proteins encoded by SEOs (sieve element occlusion) have been shown to be associated with the blockage of sieve tubes after injury in many plants, but the presence of SEO genes and their association with rubber tree laticifer plugging and latex yield remain unclear. Through a systematic identification and analysis, seven SEO genes were identified from the rubber tree genome. The physicochemical properties of their proteins, gene structures, conserved domains, and locations on chromosomes were analyzed. According to their phylogenetic distance, HbSEOs were divided into two clusters. The transcript levels of HbSEO genes varied with tissues, in which HbSEO3 and HbSEO4 were most highly expressed in leaf, bark, and latex. HbSEOs could be induced by ethephon, methyl jasmonate, mechanical injury, and tapping; furthermore, they were highly expressed in trees with short flow duration, suggesting their possible association with rubber tree laticifer plugging and latex yield. To our knowledge, this is the first report of HbSEOs in rubber trees. It provides us with a better understanding of the mechanism of laticifer plugging. [ABSTRACT FROM AUTHOR]

Purpose: Long-leg-radiography (LLR) is commonly used for the measurement of lower limb alignment. However, limb rotations during radiography may interfere with the alignment measurement. This study examines the effect of limb rotation on the accuracy of measurements based on the mechanical and anatomical axes of the femur and tibia, with variations in knee flexion and coronal deformity.Methods: Forty-five lower limbs of 30 patients were scanned with CT. Virtual LLRs simulating five rotational positions (neutral, ± 10[Formula: see text], and ± 20[Formula: see text] internal rotation) were generated from the CT images. Changes in the hip-knee-ankle angle (HKA) and the femorotibial angle (FTA) were measured on each image with respect to neutral values. These changes were related to knee flexion and coronal deformity under both weight- and non-weight-bearing conditions.Results: The measurement errors of the HKA and FTA derived from limb rotation were up to 4.84 ± 0.66[Formula: see text] and 7.35 ± 0.88[Formula: see text], respectively, and were correlated with knee flexion (p < 0.001) and severe coronal deformity (p < 0.001). Compared with the non-weight-bearing position, the coronal deformity measured in the weight-bearing condition was 2.62[Formula: see text] greater, the correlation coefficients between the coronal deformity and the deviation ranges of HKA and FTA were also greater.Conclusions: Flexion and severe coronal deformity have a significant influence on the measurement error of lower limb alignment. Errors can be amplified in the weight-bearing condition compared with the non-weight-bearing condition. When using HKA and FTA to represent the mechanical axis and the anatomical axis on LLR, limb rotation impacts the anatomic axis more than the mechanical axis in patients with severe deformities. Considering LLR as the gold standard image modality, attention should be paid to the measurement of knee alignment. Especially for the possible errors derived from weight-bearing long-leg radiographs of patients with severe knee deformities. [ABSTRACT FROM AUTHOR]

Finding a small object (e.g., earbuds, keys or a wallet) in an indoor environment (e.g., in a house or an office) can be frustrating. In this paper, we propose an innovative system, called HyperEar, to localize such an object using only a single smartphone, based on enhanced time-difference-of-arrival (TDoA) measurements over acoustic signals issued from the object. One major challenge is the hardware limitations of a Commercial-Off-The-Shelf (COTS) phone with a short separation between the two microphones and the low sampling rate of such microphones. HyperEar enhances the accuracy of TDoA measurements by virtually increasing distances between microphones through sliding the phone in the air. HyperEar requires no communication for synchronization between the phone and the object and is a low-cost and easy-to-use system. We evaluate the performance of HyperEar via extensive experiments in various indoor conditions and the results demonstrate that, for an object of 7 m away, HyperEar can achieve a mean localization accuracy of about 15 cm when the object in normal indoor environments. [ABSTRACT FROM AUTHOR]

The inhalation administration method which has been applied to treat respiratory diseases has the characteristics of painlessness high efficiency and non-invasiveness, and the drug can also be targeted at the organ level first to reduce the loss of drug during circulation. Therefore, delivering medicine by inhalation administration has brought a new turnaround for lung cancer treatment. Herein from the perspective of combining traditional drug delivery design strategies with new drug delivery methods how to improve lung targeting efficiency and treatment efficacy is discussed. We also discuss the comparative advantages of inhaled drug delivery and traditional administration in the treatment of lung cancer such as intravenous injection. And the researches are divided into different forms of inhalation administration studied in the treatment of lung cancer in recent years, such as single-component loaded and multi-component loaded systems and their advantages. Finally, the obstacles of the application of carrier materials for inhalation administration and the prospects for improvement of lung cancer treatment methods are presented. [ABSTRACT FROM AUTHOR]

Aims 3′ untranslated region (3′ UTR) of mRNA is more conserved than other non-coding sequences in vertebrate genomes, and its sequence space has substantially expanded during the evolution of higher organisms, which substantiates their significance in biological regulation. However, the independent role of 3′ UTR in cardiovascular disease was largely unknown. Methods and results Using bioinformatics, RNA fluorescent in situ hybridization and quantitative real-time polymerase chain reaction, we found that 3′ UTR and coding sequence regions of Ckip-1 mRNA exhibited diverse expression and localization in cardiomyocytes. We generated cardiac-specific Ckip-1 3′ UTR overexpression mice under wild type and casein kinase 2 interacting protein-1 (CKIP-1) knockout background. Cardiac remodelling was assessed by histological, echocardiography, and molecular analyses at 4 weeks after transverse aortic constriction (TAC) surgery. The results showed that cardiac Ckip-1 3′ UTR significantly inhibited TAC-induced cardiac hypertrophy independent of CKIP-1 protein. To determine the mechanism of Ckip-1 3′ UTR in cardiac hypertrophy, we performed transcriptome and metabolomics analyses, RNA immunoprecipitation, biotin-based RNA pull-down, and reporter gene assays. We found that Ckip-1 3′ UTR promoted fatty acid metabolism through AMPK–PPARα–CPT1b axis, leading to its protection against pathological cardiac hypertrophy. Moreover, Ckip-1 3′ UTR RNA therapy using adeno-associated virus obviously alleviates cardiac hypertrophy and improves heart function. Conclusions These findings disclose that Ckip-1 3′ UTR inhibits cardiac hypertrophy independently of its cognate protein. Ckip-1 3′ UTR is an effective RNA-based therapy tool for treating cardiac hypertrophy and heart failure. [ABSTRACT FROM AUTHOR]