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The explosion intensity and the low explosion limit of the coal dust explosion are affected by the calorific value and the heat transfer rate of the coal dust, which are closely related to the coal quality index. This paper studies experimentally the low explosive limit of the coal dust with different coal quality indexes. Based on the principal component analysis, the main factors affecting the low explosive limit are obtained by extracting the principal components from the coal quality indexes. Through comparative analysis, a regression model is proposed to predict the low explosive limit for practical applications.

Significance As a genetic malignancy, retinoblastoma (Rb) is caused by RB1 mutations; however, its developmental origin and drug agents for human Rb remain largely unexplored. Here we describe an innovative Rb organoid model derived from human embryonic stem cells with a biallelic mutagenesis of the RB1 gene. We identify tumorigenic growth in the Rb organoids, as well as properties consistent with human primary Rb. We confirm that the Rb cell of origin stemmed from ARR3+ maturing cone precursor cells and SYK inhibitors displaying a significant therapeutic response. Our elegant in-dish Rb organoid model can be used to efficiently and effectively dissect the origin of Rb and mechanisms of Rb tumorigenesis, as well as screen novel therapies., Retinoblastoma (Rb) is the most prevalent intraocular malignancy in children, with a worldwide survival rate

The results of studies on the corrosion protectiveness and thermal conductivity of reduced graphene oxide-BaSO

The growth behavior of stress corrosion cracking (SCC) of Alloy 600 with different cold-work levels was investigated in simulated boiling water reactors water environments. In addition, a correlation of cold-work levels, grain boundary characteristic, and the SCC growth behavior of Alloy 600 were studied. The results show that grains with high residual strain caused by cold work provide transgranular crack growth paths. The SCC growth rates of the specimens also increase with an increase in the degree of cold work and decrease remarkably after switching to the hydrogen water chemistry environment. Grain boundary character proves to be a factor more important than the localized strain concentration at the grain boundary in terms of its role in the intergranular crack growth rate of the Alloy 600 with a cold-work degree from 20% to 30%.

Circular RNAs (circRNAs) represent a class of noncoding RNAs with a wide expression pattern, and they constitute an important layer of the genome regulatory network. To date, the expression pattern and regulatory potency of circRNAs in the retina, a key part of the central nervous system, are not yet well understood. In this study, RNAs from five stages (E18.5, P1, P7, P14, and P30) of mouse retinal development were sequenced. A total of 9,029 circRNAs were identified. Most circRNAs were expressed in different stages with a specific signature, and their expression patterns were different from those of their host linear transcripts. Some circRNAs could act as sponges for several retinal microRNAs (miRNAs). Furthermore, circTulp4 could function as a competitive endogenous RNA (ceRNA) to regulate target genes. Remarkably, silencing circTulp4 in vivo led to mice having a thin outer nuclear layer (ONL) and defective retinal function. In addition, we found that circRNAs were dysregulated at a much earlier time point than that of disease onset in a retinal degeneration model (rd8 mice). In summary, we provide the first circRNA expression atlas during retinal development and highlight a key biological role for circRNAs in retinal development and degeneration.

The present study focuses on the corrosion behavior of 304L stainless steel in crevice corrosion environments. The specimen with a salt deposit of 0.1 g/m2 was assembled with a crevice former made of Poly-tetra fluoroethylene (PTFE) to make a test device. The assembled test devices were kept at the ambient temperature of 45 °C in combination with a relative humidity of 45%, 55%, and 70%. After testing for 5000 h, the corroded area of the specimen exposed to 70% humidity was three times larger than that subjected to 45% humidity. For the specimen sustaining a tensile force, the crack growth rate was approximately 1.4 mm/year at the stress level of 300 MPa in a crevice corrosion environment with 0.1 g/m2 of sea salt deposited on the surface. The small portion of intergranular cracking occurred at the surface due to the existed strain on the surface. As cracks propagate in a grain, the grain undergoes a greater localized deformation, and some secondary cracks would develop inside the grain; transgranular cracking was vigorous due to the path corrosion that nucleated at the slip steps.

Porcine circovirus associated diseases (PCVADs) are among the most important diseases affecting the worldwide swine industry. Vaccination against porcine circovirus type 2 (PCV2) infection has been utilized for disease control and effectively reduces clinical signs of PCVADs. To evaluate the efficacy of the PCV2 vaccine in field farms, we conducted a trial using conventional pigs immunized with the subunit PCV2 vaccine followed by PCV2 challenge. Immunized pigs demonstrated lower serum viral loads, less viral antigen staining in lymph nodes, and higher average daily weight gain, confirming the protective efficacy of the vaccine. However, low levels of PCV2 infection were still detected in vaccinated pigs after challenge, suggesting that the PCV2 vaccine was unable to eradicate the virus, which could lead to asymptomatic PCV2 subclinical infection (PCV2-SI) in pig farms. Additionally, PCV2 infection is a risk factor for impaired pig immune response development during the weaning to growth stages, which is a crucial period to receive vaccines against classical swine fever (CSF). Therefore, the impact of PCV2-SI or PCV2-systemic disease (PCV2-SD) on live attenuated CSF vaccine was investigated. After PCV2 challenge, there was no difference in levels of classical swine fever virus (CSFV) neutralizing antibodies (NA) between pigs with PCV2-SD and PCV2-SI, suggesting that the efficacy of CSF vaccine was compromised. Moreover, results of long-term monitoring of CSFV NA titers in PCV2-SI pigs with minimized interference by maternally-derived antibodies suggested that serum PCV2 viral loads greater than 102 copies/mL may compromise the efficacy of CSF vaccine. Overall, a conventional pig model was established to demonstrate the impaired efficacy of the subunit PCV2 vaccine and its impact on the CSF vaccine in vaccination-challenge trials. Additionally, the impaired efficacy of the PCV2 vaccine resulted in increased PCV2-SI, eventually leading to compromised the live attenuated CSF vaccine induced NA response in field farm applications.

In relation with the potential applications of CO2 foam technology on Enhanced Oil Recovery and CO2 geological storage, the foam assisted CO2 displacement process in a surfactant solution and oil pre-saturated porous medium is experimentally investigated with special attention on the dynamic foam propagation behavior in the entrance region of porous media. Computational Tomography (CT) imaging is employed to visualize the transient CO2 foam sweep process and the dual-energy CT measurement is performed to obtain the dynamic three phase saturation distributions along the sample core. Studying parameters include the comparison with N2 foam, system backpressure and the porous medium permeability. It is found foam could push most of the liquid phase in the latter part of the porous media but leaves the forepart of the sample less flooded, showing a clear entrance effect of foam flooding process. Compared to CO2 foam, N2 foam displacement process shows higher liquid phase saturation in the entrance section and presents less oil recovery rate. Elevating system backpressure to 1.0 MPa leads to less pressure drop for CO2 foam flooding process without compromising the oil phase sweep efficiency. The CO2 foam flooding process in lower permeable medium shows higher pressure drop and higher oil recovery rate. The mechanisms for the inlet behavior of the foam displacement processes have been scrutinized based on good qualitative and quantitative agreement of the experimental and numerical results with the stochastic bubble population balance model.

Numerical investigations were carried out with special attentions on the inlet and outlet behaviors of foam flow process in a homogeneous porous media with confined entrance and exit boundaries. The Stochastic Bubble Population (SBP) balance model, which usually involves two parameters of the bubble generation rate Kg and the maximum bubble density n∞ for bubble number prediction, was employed to study the dynamic foam generation and development process in porous media. With introduction the Kfp parameter to take into account the foam phase relative permeability reduction effect, the control equations of the two-phase flow process in a two-dimensional computational domain were solved with the IMPES algorithm and the inlet and outlet behavior of the foam displacement process were scrutinized based on detailed analysis of the bubble density, water phase pressure and water phase saturation distributions in porous medium. Numerical results showed a clear entrance effect of higher water saturation, lower pressure gradient and developing bubble density in the inlet region of the porous media in the transient foam displacement process, whereas the confined exit results in elevating water saturation and decreasing pressure gradient towards the outlet of the core. Parametric studies on Kg, n∞, Kfp and inlet & outlet sizes D indicate higher bubble generation rate could remarkably suppress the entrance region in the foam seepage process, while the higher maximum bubble number did not lead to obvious change of the foam flow behavior in the inlet and outlet region, although it could produce higher absolute values of bubble density and pressure drop along the core. With lower Kfp values, the strong foam flooding behavior could be properly predicted with much higher pressure drop and lower water saturation. Two dimensional numerical results at various inlet and outlet sizes clearly show the confined geometry effect on foam flow characteristics with smaller sizes corresponding to longer inlet and outlet regions. Computational domain and numerical results were validated through comparisons with corresponding experimental setup and CT measurement results. It is observed that, the numerical simulation could reproduce not only qualitatively but also quantitatively the experimentally obtained water saturation distribution and pressure drop result. It is concluded that the mechanistic stochastic bubble population model could be reasonably employed on prediction of the inlet and outlet behavior in the transient foam flow process in the homogeneous porous media.

Adenosine diphosphate (ADP)-ribosylation factor-like 2 (ARL2) protein participates in a broad range of cellular processes and acts as a mediator for mutant ARL2BP in cilium-associated retinitis pigmentosa and for mutant HRG4 in mitochondria-related photoreceptor degeneration. However, mutant ARL2 has not been linked to any human disease so far. Here, we identified a de novo variant in ARL2 (c.44G > T, p.R15L) in a Chinese pedigree with MRCS (microcornea, rod-cone dystrophy, cataract, and posterior staphyloma) syndrome through whole-exome sequencing and co-segregation analysis. Co-immunoprecipitation assay and immunoblotting confirmed that the mutant ARL2 protein showed a 62% lower binding affinity for HRG4 while a merely 18% lower binding affinity for ARL2BP. Immunofluorescence images of ARL2 and HRG4 co-localizing with cytochrome c in HeLa cells described their relationship with mitochondria. Further analyses of the mitochondrial respiratory chain and adenosine triphosphate production showed significant abnormalities under an ARL2-mutant condition. Finally, we generated transgenic mice to test the pathogenicity of this variant and observed retinal degeneration complicated with microcornea and cataract that were similar to those in our patients. In conclusion, we uncover ARL2 as a novel candidate gene for MRCS syndrome and suggest a mitochondria-related mechanism of the first ARL2 variant through site-directed mutagenesis studies.

Circular RNAs (circRNAs) belong to an endogenous class of RNA molecules with both ends covalently linked in a circle. Although their expression pattern in the mammalian brain has been well studied, the characteristics and functions of circRNAs in retinas remain unknown. To reveal the whole expression profiles of circRNAs in the neural retina, we investigated retinal RNAs of human, monkey, mouse, pig, zebrafish and tree shrew and detected thousands of circRNAs showing conservation and variation in the retinas across different vertebrate species. We further investigated one of the abundant circRNAs, circPDE4B, identified in human retina. Silencing of circPDE4B significantly inhibited the proliferation of human A549 cells. Functional assays demonstrated that circPDE4B could sponge miR-181C, thereby altering the cell phenotype. We have explored the retinal circRNA repertoires across human and different vertebrates, which provide new insights into the important role of circRNAs in the vertebrate retinas, as well as in related human diseases.

A coupled Computational Fluid Dynamics-Discrete Element Method (CFD-DEM) approach is used to investigate the hydrodynamic and mechanical behavior of multi-particle, which settle and horizontally transport between two parallel plates. The particle-fluid interaction is two-way coupled, while inter-particle and particles-walls interactions are calculated based on the soft-sphere model. The Joint Roughness Coefficient (JRC) is used to represent the roughness of planar walls, and its effect on particle transport is quantitatively studied. When particles transport between two parallel smooth plates, the planar walls exert extra hydrodynamic retardation, which causes particle transport velocity to decrease with the decrease in the aperture between two plates. In contrast, when particles transport between two parallel rough plates, due to frequent interaction between particles, the mechanical interaction-induced retardation starts to work and further decreases particle transport velocity. Particle longitudinal migration is frequent because of inter-particle interaction, which hinders its transverse transport and even causes particle agglomeration in a duct during horizontal transport. In addition, the mechanical retardation is significantly dependent of particle transport regimes, and its effect gradually increases and changes to be dominant at high particle Reynold number regime.

Effective ionic/electronic percolation, especially in a thick electrode, has a decisive influence on the electrochemical properties of rechargeable batteries, such as material usefulness, electrode reversibility and cell lifespan. Using low cost and highly safe rechargeable aqueous zinc ion batteries (RAZBs) as a model, in this paper a dense electrode architecture is presented which is constructed using silver vanadium oxide@water-pillared vanadium oxide core–shell (Ag0.333V2O5@V2O5·nH2O) coaxial nanocables that maintain optimal ion/electron percolation without admixing the additional inert component. This electrochemically robust architecture is composed of a highly electronic conductive phase of silver vanadate and a highly ionic conductive phase of the water-pillared V2O5·nH2O structure, which synergistically forms a coaxial nanocable structure benefiting ion/electron contact and penetration in a thick electrode. As expected, the Ag0.333V2O5@V2O5·nH2O coaxial nanocables deliver a high reversible capacity (312.1 mA h g−1 at 0.5 A g−1), excellent rate capability (196.7 mA h g−1 at 3.0 A g−1) and stable cycling performance (261.7 mA h g−1 at 0.5 A g−1 after 100 cycles). The investigation of the electrochemical reaction kinetics reveals a combinatorial fast pseudocapacitive reaction and a diffusion controlled intercalation reaction. The lower percolation threshold of both ions and electrons should be responsible for the better electrode kinetics and the improved zinc ion storage capacity of the Ag0.333V2O5@V2O5·nH2O coaxial nanocables compared to that of pristine Ag0.333V2O5 electrodes. It is anticipated that the as-proposed strategy of constructing effective ionic/electronic percolating thick electrodes to boost the reaction kinetics can be applied to other active materials for constructing practical multivalent batteries.

The results of studies on the corrosion protectiveness and thermal conductivity of reduced graphene oxide–BaSO4 epoxy composites are reported here. A commercial epoxy resin and reduced graphene oxide (rGO) were blended with a hardening reagent and then mixed with prepared BaSO4–epoxy resin (B–epoxy). The reduced graphene oxide–BaSO4–epoxy composite (rGO–B–epoxy) paste was used to coat the surfaces of Al 7205 alloy and the corrosion and thermal properties were investigated. A corrosion test in a 3.5 wt% synthetic sea water solution showed that the composite coating containing BaSO4 had the best corrosion resistance. Moreover, the rGO–B–epoxy composite showed better protection against corrosion than the epoxy alone. The rGO–B–epoxy composite with 5 wt% BaSO4 had an in-plane coefficient of thermal conductivity of approximately 165.0 W/m K, and the in-plane thermal diffusivity was 71.38 mm2/s. In standard thermal conductivity tests, all three samples had values below 40 W/m K. The rGO–B–epoxy composites showed good surface corrosion protection and in-plane thermal conductivity.

Light Detection and Ranging (LiDAR) is a high-price system for wide-usage automotive driving requirements. The design, implementation, and validation of a performance-complexity efficient LiDAR system are introduced in this paper. A Time-to-Digit (TDC) chip with a low-cost Data-Processing (DP) chip is utilized in this system. The proposed chips have been well validated and can be utilized as processing cores for a generic LiDAR system. The measurement accuracy is a comparison with a high-price commercial product of Time-Correlated Single-Photon-Counting (TCSPC). The values show the proposed system accuracy is respectable for the comparison by many distances from 4.8m to 44.6m, the maximum difference is 0.3%.

Aiming at the problem of virtual link priority mapping, the paper proposes a novel candidate path ranking algorithm. The proposed algorithm converts the problem of candidate path ranking into a machine learning binary classification problem. More specifically, the proposed algorithm evaluates the probability that the virtual link is successfully mapped onto the candidate path. All candidate paths are sorted according to probability, and the path with the highest probability of success is selected. The simulation shows that compared with virtual link priority mapping algorithm based on the shortest path, the new algorithm has better blocking rate performance.

Abundant retinal microRNA-183 cluster (miR-183C) has been reported to be a key player in photoreceptor development and functionality in mice. However, whether there is a protagonist in this cluster remains unclear. Here, we used a mutant mouse model to study the role of miR-96, a member of miR-183C, in photoreceptor development and functionality.The mature miR-96 sequence was removed using the CRISPR/Cas9 genome-editing system. Electroretinogram (ERG) and optical coherence tomography (OCT) investigated the changes in structure and function in mouse retinas. Immunostaining determined the localization and morphology of the retinal cells. RNA sequencing was conducted to observe retinal transcription alterations.The miR-96 mutant mice exhibited cone developmental delay, as occurs in miR-183/96 double knockout mice. Immunostaining of cone-specific marker genes revealed cone nucleus mislocalization and exiguous Opn1mw/Opn1sw in the mutant (MT) mouse outer segments at postnatal day 10. Interestingly, this phenomenon could be relieved in the adult stages. Transcriptome analysis revealed activation of microtubule-, actin filament-, and cilia-related pathways, further supporting the findings. Based on ERG and OCT results at different ages, the MT mice displayed developmental delay not only in cones but also in rods. In addition, a group of miR-96 potential direct and indirect target genes was summarized for interpretation and further studies of miR-96-related retinal developmental defects.Depletion of miR-96 delayed but did not arrest photoreceptor development in mice. This miRNA is indispensable for mouse photoreceptor maturation, especially for cones.

This study simulated the after-burned zirconium cladding oxidation in air at temperatures between 500 and 800 °C. The weight changes of Zircaloy-4 cladding with hydrogen contents of 100–1000 ppm continuously measured through thermogravimetric analysis (TGA) during oxidation tests at different temperatures in an air atmosphere. The TGA results indicate a transition of oxidation kinetics from a parabolic rate law to a linear rate law for as-received and hydrided Zircaloy-4 cladding. The hydrogen concentration of Zircaloy-4 had a marked effect on its pre-transition oxidation in air between 500 and 800 °C. For all samples, the linear oxidation (post transition stage) at 650 °C, which is the critical oxidation temperature, displays a similar trend. In addition, scanning electron microscopy and transmission electron micros-copy examinations indicated the presence of a few and numerous discontinuous micro-cracks in the oxide layer in the pre-transition and post-transition stages, respectively.

In this study, citrate synthase gene(CIT2), and malate synthase gene(MLS1) were successfully knocked out in β-amyrin-producing yeast cells by using CRISPR/CAS9. The promoter of phosphoglucose isomerase gene(PGI1) was replaced by that of cytochrome c oxidase subunit Ⅶa(Cox9)to weaken its expression, aiming to channel more carbon flux into the NADPH-producing pathway. The fermentation results showed that CIT2 deletion had no effect on the β-amyrin production. Compared with the control strain, the production of β-amyrin was increased by 1.85 times after deleting MLS1, reaching into 3.3 mg·L~(-1). By replacing the promoter of PGI1, the β-amyrin yield was 3.75 times higher than that of the control strain, reaching up to 6.7 mg·L~(-1). This study successfully knocked out the CITT2 and MLS1 genes and weakened the PGI1 gene by using CRISPR/CAS9, which directly influenced the production of β-amyrin and provided some reference for the the metabolic engineering of triterpernoid producing strain.

Rheological properties of supercritical CO 2 (ScCO 2 ) foam fluids are essential to understand foam displacement mechanisms in the research & development of efficient CO 2 -EOR and CO 2 geological storage technologies. In this paper, a systematic laboratory study concerning non-Newtonian ScCO 2 foam flow characteristics in a straight tube was carried out under different gas-liquid ratios. Through modifying experimental pressure and temperature conditions, comparative studies on liquid phase CO 2 and gaseous CO 2 foam rheology were also carried out. The experimental results show obvious shear-thickening behavior for the scCO 2 foam (45 °C and 8.0 MPa) with flow behavior index increasing from 1.03 to 1.76 with increasing foam quality. And the apparent viscosity of scCO 2 foam could reach up to 140 times of the single-phase water. The liquid phase CO 2 foam (25 °C and 8.0 MPa) also exhibits clearly the shear-thickening characteristics with flow behavior index ranging from 1.56 to 1.88. The gaseous CO 2 foam, on the other hand, behaves in a shear-thinning or pseudo-plastic manner with flow behavior index of 0.70 2 and liquid CO 2 bulk foam, which mainly contributes to the shear thickening behavior for ScCO 2 and liquid CO 2 foam fluid.

The hot cracking behavior of Ni-based Alloy 52M weld overlay with respective SS 307Si and SS 308L buffer layers was investigated. The dilution level of SS 307Si buffer layer is a little higher than that of SS 308L. However, the hot crack length of overlay with SS 307Si buffer layer is shorter and the SS 307Si layer has higher mechanical properties than that of SS 308L layer. As observed by SEM and EBSD, ferrites precipitated in SS 307Si buffer layer are in vermicular skeletons dotted with lathy precipitates, which have a little higher local stain than that of SS 308L weld. However, Alloy 52M weld around SS 307Si fusion boundary has a lower degree of local distortion. The results generalize that the SS 307Si buffer layer is marginally better for reducing hot cracking susceptibility, owing to its lower local stain and slightly higher mechanical strength.

The etiology of the highly myopic condition has been unclear for decades. We investigated the genetic contributions to early-onset high myopia (EOHM), which is defined as having a refraction of less than or equal to −6 diopters before the age of 6, when children are less likely to be exposed to high educational pressures. Trios (two nonmyopic parents and one child) were examined to uncover pathogenic mutations using whole-exome sequencing. We identified parent-transmitted biallelic mutations or de novo mutations in as-yet-unknown or reported genes in 16 probands. Interestingly, an increased rate of de novo mutations was identified in the EOHM patients. Among the newly identified candidate genes, a BSG mutation was identified in one EOHM proband. Expanded screening of 1,040 patients found an additional four mutations in the same gene. Then, we generated Bsg mutant mice to further elucidate the functional impact of this gene and observed typical myopic phenotypes, including an elongated axial length. Using a trio-based exonic screening study in EOHM, we deciphered a prominent role for de novo mutations in EOHM patients without myopic parents. The discovery of a disease gene, BSG, provides insights into myopic development and its etiology, which expands our current understanding of high myopia and might be useful for future treatment and prevention.

Human visual acuity is anatomically determined by the retinal fovea. The ontogenetic development of the fovea can be seriously hindered by oculocutaneous albinism (OCA), which is characterized by a disorder of melanin synthesis. Although people of all ethnic backgrounds can be affected, no efficient treatments for OCA have been developed thus far, due partly to the lack of effective animal models. Rhesus macaques are genetically homologous to humans and, most importantly, exhibit structures of the macula and fovea that are similar to those of humans; thus, rhesus macaques present special advantages in the modeling and study of human macular and foveal diseases. In this study, we identified rhesus macaque models with clinical characteristics consistent with those of OCA patients according to observations of ocular behavior, fundus examination, and optical coherence tomography. Genomic sequencing revealed a biallelic p.L312I mutation in TYR and a homozygous p.S788L mutation in OCA2, both of which were further confirmed to affect melanin biosynthesis via in vitro assays. These rhesus macaque models of OCA will be useful animal resources for studying foveal development and for preclinical trials of new therapies for OCA.

Information technology development leads to the data explosion in many industries. In the era of big data, telecom operator stores huge amount of data, namely telecom big data. Telecom operator can employ data mining and analysis to seek the valuable information from telecom big data. In this paper, we design a novel big data assisted analysis architecture for telecom operator. The proposed architecture collects operation support system data and business support system data of telecom operator. Based on these data, the architecture draws the portrait of each user. Then, the user trajectory is analyzed. Furthermore, the proposed architecture takes the service behavior analysis. Finally, we apply the proposed big data assisted analysis architecture to the local telecom operator.

In the past thirty years, China experiences fast development in terms of economic and technology. This leads to the frequent exchange and communication among different cities. Specifically, meetings, sports, and industry exchanges at various levels are becoming more frequent and popular. Above events have significant impact on the city, hence, government/organizer should quantitatively evaluate the impact of events. Based on the various data of telecom operators, this paper proposes an insight scheme for large-scale events of the city. The proposed scheme can analyze the changes of the users scale and the business volume. In addition, this scheme also analyzes the aggregation areas of users before and after events and other characteristics. Especially, for the characteristics of external users from other cities, the proposed scheme can provide the data analysis results, in this way to support both the organizer and the government of the host city. Finally, the organizer and the government can provide good services.

Pollution prevention and control is one of the three key issues in China recently. Telecom operators have the data of millions of users, including identity attributes, mobile trajectories, and service behavior characteristics etc. On the premise of guaranteeing user data security, pollution prevention and control work can be extended from the source control, transmission characteristics and other aspects to the impact on the population. Thus, it can realize the comprehensive assessment of pollution prevention and control. This paper focuses on the field of air pollution prevention and control. We propose a refined pollution prevention and control method based on telecom operator data. This method can predict the users' distribution. Furthermore, it can analyze and predict the impacted users of air pollution, and finally to assist the Chinese "Blue Sky Plan".

The operation condition of wireless system directly impacts both the system performance and the quality of experience (QoE). On the basis of telecom operator data, this paper designs a comprehensive operation and revenue analysis (CORA) algorithm for LTE/5G wireless system. The objective of the proposed CORA algorithm is to analyze and evaluate both the operation state and the revenue of base station (BS) in the wireless system. The designed CORA algorithm is applied in the realistic 4G wireless system. The CORA algorithm can assist telecom operator to effectively analyze and evaluate the BS comprehensive state of operation and revenue.

The next-generation (5G) wireless networks have been evolving into very complex systems due to the diversified service requirements, heterogeneity in applications, devices, and networks. The network operators need to make the best use of the available resources, for example, power, spectrum, infrastructures, as well as data. Large amounts of data, generated from the network and the subscribers, would dramatically help make the system smart and efficient by advanced exploiting. Besides, the synergy of the 5G and the big data would create new services, which promotes a faster digital transformation of the vertical industries. In this paper, we first present the evolution of the big data in the uprising 5G era. Then, an overview of the interplay between the 5G and the big data is provided. Following gives the discussion on challenges and trends of the development of 5G and big data. To further illustrate the benefits, data-driven services are studied.

With the development of information technology, we are living in a society of data explosion. In precise marketing field, how to classify the population and identify the target users has attracted much concern. Based on telecom big data, this paper has proposed a precise user classification scheme using decision tree. According to the classification result, potential users can be identified and focused on, which can dramatically improve the marketing efficiency and effectiveness with limited marketing expense.

An interesting phenomenon, I D /I G intensity ratios between D mode and G mode increase around micro-wells, is observed in defective graphene sensors. A modified phenomenological model depicting the relation between I D /I G and the built-in stress is developed to reveal the physical mechanism of the above phenomenon. It is demonstrated that the initial defects in graphene gas sensors arising from fabrication processes can further propagate under the built-in tension resulting in increasing the defect density. The underlying mechanism is that the built-in stress provides the energy for the defect propagation of stretched graphene. The work could be helpful for applications of defective graphene-based devices.

In this study, the synthetic pathway of β-amyrin was constructed in the pre-constructed Saccharomyces cerevisiae chassis strain Y0 by introducing β-amyrin synthase from Glycyrrhiza uralensis, resulting strain Y1-C20-6, which successfully produced β-amyrin up to 5.97 mg·L~(-1). Then, the mevalonate pyrophosphate decarboxylase gene(ERG19), mevalonate kinase gene(ERG12), 3-hydroxy-3-methylglutaryl-CoA synthase gene(ERG13), phosphomevalonate kinase gene(ERG8) and IPP isomerase gene(IDI1)were overexpressed to promoted the metabolic fluxto the direction of β-amyrin synthesis for further improving β-amyrin production, resulting the strain Y2-C2-4 which produced β-amyrin of 10.3 mg·L~(-1)under the shake flask fermentation condition. This is 100% higher than that of strain Y1-C20-6, illustrating the positive effect of the metabolic engineering strategy applied in this study. The titer of β-amyrin was further improved up to 157.4 mg·L~(-1) in the fed-batch fermentation, which was almost 26 fold of that produced by strain Y1-C20-6. This study not only laid the foundation for the biosynthesis of β-amyrin but also provided a favorable chassis strain for elucidation of cytochrome oxidases and glycosyltransferases of β-amyrin-based triterpenoids.

Purpose MicroRNA-182 (miR-182) is abundantly expressed in mammalian retinas; however, the association between miR-182 and retinal function remains unclear. In this study, we explored whether miR-182 contributes to functional decline in retinas using a miR-182 depleted mouse. Methods Electroretinogram (ERG) amplitudes at different ages were measured in miR-182 knockout (KO) mice. The thickness and lamination of retinas were assessed using a color fundus camera and high-resolution optical coherence tomography. Expression levels of key photoreceptor-specific genes and the miR-183/96/182 cluster (miR-183C) were quantified using quantitative real-time PCR. RNA sequencing and light-induced damage were carried out to observe the changes in the retinal transcriptome and sensitivity to light damage in the miR-182 KO mice. Results The ERG recording reveals that the ERG response amplitude decreased both at early and later ages when compared with control littermates. The expression of some key photoreceptor-specific genes was down-regulated with deletion of miR-182 in retina. RNA sequencing indicated that some biological processes of visual system were affected, and the numbers of potential target genes of miR-182 were presented in the mouse retina using bioinformatics analysis. The miR-182 KO mice were characterized by progressively losing the outer segment after being treated with light-damage exposure. The thickness and lamination of retina as well as compensatory expression of miR-183C showed no apparent changes in retina of miR-182 KO mice under normal laboratory lighting condition. Conclusions Our findings provided new insights into the relationship between the miR-182 and retinal development and revealed that miR-182 may play a critical role in maintaining retinal function.

Retinoblastoma (Rb) is the most prevalent intraocular malignant tumour in children with survival rate less than 30% globally. Its developmental origin and drug agents remain largely unexplored. Here, we developed the first organoid Rb model derived from human embryonic stem cells (hESCs) with a biallelic knockout (RB1-/-) or mutagenesis (RB1Mut/Mut). These organoid retinoblastomas exhibit extremely consistent properties of Rb tumourigenesis, transcriptome, and genome-wide methylation. We found Rb originated from ARR3+ maturing cone precursors during development and a new unfolded protein response cell type. A key PI3K-Akt pathway was aberrantly regulated, and its activator SYK was significantly upregulated. Furthermore, the SYK inhibitors induced a more significant therapeutic response from early-stage organoid Rb. In conclusion, we established a novel organoid Rb model derived from human ESCs in a dish and discovered its cell-of-origin and potential drug agents, thus shedding light on the development and therapeutics of other human cancers.

In this study, Zn/15Al, Al and Inconel 625 coatings were applied on low carbon steel substrates by twin wire arc spray process as a corrosion and wear protection barrier against the marine atmosphere. The wear behavior of the coating layer was characterized by a pin-on-disk apparatus at a combination condition of three normal loads and two sliding speeds. The wear tests were conducted in a 3.5 wt.% NaCl solution to evaluate the wear resistance of the coatings in a corrosive environment. The results suggested that the Inconel 625 coating had a better wear resistance in a 3.5 wt.% NaCl solution as compared to the ZnAl and Al specimens. Zn/15Al coatings revealed less wear resistant in a corrosive environment due to the rupture of the oxide film on the coating surface during wear. For the sacrificial protection coatings of Zn/15Al and Al, the characteristics of surface oxide film play a vital role in the wear resistance of the coating materials.

Eight closely biogenetically-related aromadendrane-type sesquiterpenoids, six of them new, scedogiines A–F (1–3, 6–8), together with a new polyketide scedogiine G (9) were discovered from the culture broth of the marine-derived fungus Scedosporium dehoogii F41-4 by NMR-guided isolation. Their structures were determined from extensive NMR and HR-ESI-MS data. The absolute configurations of the new sesquiterpenoids were elucidated by ECD calculation. Plausible biogenetic pathways of the aromadendrane analogues were postulated.