Generation of genetically uniform non-human primates may help to establish animal models for primate biology and biomedical research. In this study, we have successfully cloned cynomolgus monkeys ...(Macaca fascicularis) by somatic cell nuclear transfer (SCNT). We found that injection of H3K9me3 demethylase Kdm4d mRNA and treatment with histone deacetylase inhibitor trichostatin A at one-cell stage following SCNT greatly improved blastocyst development and pregnancy rate of transplanted SCNT embryos in surrogate monkeys. For SCNT using fetal monkey fibroblasts, 6 pregnancies were confirmed in 21 surrogates and yielded 2 healthy babies. For SCNT using adult monkey cumulus cells, 22 pregnancies were confirmed in 42 surrogates and yielded 2 babies that were short-lived. In both cases, genetic analyses confirmed that the nuclear DNA and mitochondria DNA of the monkey offspring originated from the nucleus donor cell and the oocyte donor monkey, respectively. Thus, cloning macaque monkeys by SCNT is feasible using fetal fibroblasts.
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•Somatic cell nuclear transfer (SCNT) using fetal fibroblasts yielded two live monkeys•Epigenetic modulators promoted development and pregnancy rate of SCNT embryos•SCNT using adult cumulus cells yielded live births of monkeys that were short-lived•Genetic analysis confirmed the clonal origin of the SCNT monkey offspring
Generation of cloned cynomolgus monkeys by somatic cell nuclear transfer using fetal monkey fibroblasts.
Two-dimensional materials (2DMs) such as graphene and black phosphorus (BP) have aroused considerable attentions in the past few years. Engineering and enhancing their light-matter interaction is ...possible due to their support for localized surface plasmon resonances in the infrared regime. In this paper, we have proposed an infrared broadband absorber consisting of multilayer graphene-BP nanoparticles sandwiched between dielectric layers. Benefiting from the properties of graphene and BP, the absorber exhibits both perfect broadband responses and strong anisotropy beyond individual graphene and BP layers. The absorber is tunable with the variation of geometric parameters as well as the doping levels of graphene and BP. The physical insight is revealed by electric field distributions. Furthermore, the angular robustness for incident wave is investigated. The proposed anisotropic omnidirectional broadband absorber may have promising potential applications in various biosensing, communication and imaging systems.
The key to leak detection and location in water supply pipelines is signal denoising and feature extraction. First, in this paper, an improved spline-local mean decomposition (ISLMD) is proposed to ...eliminate noise interference. Based on the ISLMD decomposition of a signal, the cross-correlation function between the reference signal and the product functions component can be obtained. And then the PF component containing the leak information can be extracted reasonably. Compared with improved local mean decomposition, the ISLMD has higher accuracy in leak location. Second, an image recognition method using a convolutional neural network for leak detection is proposed, which can better address the problem that the features of different leak apertures or locations are highly similar to each other. The images from the conversion of the reconstructed signals are used as the input of the AlexNet model, which is capable of adaptive extraction of leak signal features. The trained AlexNet model can effectively detect different leak apertures. Finally, the signal time-delay between the upstream and downstream pressure transmitters caused by the leak and propagation of negative pressure wave is determined according to generalized cross-correlation analysis, and thereby, the leak location is obtained. The experimental results show that the proposed method is effective for leak detection and location.
With the rapid development of China’s national economy, the effects of traditional public security management methods have been greatly weakened, and various new types of criminal activities have ...continued to occur. Social development has gradually separated from the previous model, and new social contradictions have become prominent. These social contradictions not only impact the lifestyle of ordinary individuals, but also affect the development of society. The data contains the laws of social development and crime governance. How criminal governance adapts to the big data wave has become the key to carrying out the number management in the three-dimensional security prevention and control. The data culture has promoted the transformation of the social governance model and has also led to the transformation of the social science research paradigm. At present, most of the research on big data is only from the perspective of informatics, and there is not much discussion about big data from the legal system level. With the advent of the era of big data, a series of problems have come along. In addition to strengthening the security of the big data operation process at the technical level, it is necessary to strengthen research from a technical level. In this paper, we propose a smart crime prevention and control big data analysis system based on machine Internet of Things and industrial object system. The experimental results show that the proposed method has higher data collection rate and crime prevention and control efficiency.
Modulating spatial near-infrared light for ultra-compact electro-optic devices is a critical issue in optical communication and imaging applications. To date, spatial near-infrared modulators based ...on graphene have been reported, but they showed limited modulation effects due to the relatively weak light-graphene interaction. In combination with graphene and metallic nanoslits, we design a kind of ultrathin near-infrared perfect absorber with enhanced spatial modulation effects and independence on a wide range of incident angles. The modulated spectral shift of central wavelength is up to 258.2 nm in the near-infrared range, which is more promising in applications than state-of-the-art devices. The modulation enhancement is attributed to the plasmonic nanoslit mode, in which the optical electric field is highly concentrated in the deep subwavelength scale and the light-graphene interaction is significantly strengthened. The physical insight is deeply revealed by a combination of equivalent circuit and electromagnetic field analysis. The design principles are not only crucial for spatial near-infrared modulators, but also provide a key guide for developing active near-infrared patch nanoantennas based on graphene.
Medical information system is a comprehensive system which integrates the application of medicine, information, management, computer and other disciplines. It has been widely used in the social ...medical security system. But with the rapid development of Internet plus medical technology, the risk of malicious invasion has increased dramatically, which gradually exposes the problem of inadequate medical information security. Therefore, effective detection of medical information system network intrusion and timely prevention of network threats have become the focus of attention and research in this field. Intrusion detection is a common detection method in network security, it plays a very important role in network security. Traditional intrusion detection is mostly based on rule matching, statistics and other methods. With the advent of the era of big data, traditional intrusion detection can not play a good performance, especially in the face of massive, complex and unbalanced intrusion data. The privacy data access monitoring system based on virtual computing environment can monitor the access of privacy data in two levels, namely, tracking the flow of privacy data within the host and tracking the propagation of privacy data between hosts. In the host, we can customize the taint propagation rules to achieve fine-grained capture of privacy data violations in the virtual computing environment. Hence, this paper studies the medical data intrusion detection technology based on virtual data pipeline from the assurance perspectives. The model is designed and implemented with the discussions of the performance. The experimental results have proven that the proposed model is efficient.
Recent success in the derivation of haploid embryonic stem cells （haESCs） from mouse via parthenogenesis and androgenesis has enabled genetic screening in mammalian cells and generation of ...gene-modified animals. However, whether haESCs can be derived from primates remains unknown. Here, we report the derivation of haESCs from parthenogenetic blastocysts of Macaca fascicularis monkeys. These cells, termed as PG-haESCs, are pluripotent and can differentiate to cells of three embryonic germ layers in vitro or in vivo. Interestingly, the haploidy of one monkey PG-haESC line （MPH1） is more stable compared with that of the other one （MPH2）, as shown by the existence of haploid cells for more than 140 days without fluorescence-activated cell sorting （FACS） enrichment of haploid cells. Importantly, transgenic monkey PG-haESC lines can be generated by lentivirus- and piggyBac transposon-mediated gene transfer. Moreover, genetic screening is feasible in monkey PG-haESCs. Our results demonstrate that PG- haESCs can be generated from monkeys, providing an ideal tool for genetic analyses in primates.
Here, a thermally switching absorber based on a one-dimensional photonic crystal containing a phase change material is proposed, which operates in the terahertz range. Vanadium dioxide (VO
2
) is ...utilized as the phase-change material in the structure, which shows semiconductor-to-metal transition with varying temperatures. The frequency of switching is regulated in such a way that according to the VO
2
thickness, the absorption band displays switching properties from low to high frequencies and vice versa, and also from narrow to broadband absorption at the same frequency when the temperature increases from 300 to 350 K. The absorptivity in both bands is obtained at over 90%. Field distribution profile and the impedance matching technique elucidate the physical mechanism of absorption peaks. At 300 K, maximum absorption is realized by localizing the intensity at the defect layer, and at 350 K, the Tamm state excitation makes it possible to achieve perfect absorption. Also, relative impedance matching of the structure at the peak frequencies with vacuum impedance explains high absorption. Finally, the effects of incidence angle and polarization of light that influence the absorption peaks are analyzed. According to the results, the proposed absorber, despite showing switching features between two bands, also can be adjusted by incident angle for both TE and TM polarizations. This work may have potential applications in designing terahertz switches, filters, and sensors.
Traditional identification tags in the radio or optical domain are unsatisfactory in terms of size and security. In this paper, we theoretically demonstrate an ultracompact and chipless ...identification tag in the terahertz band using multi-resonant metasurfaces based on graphene. Benefiting from the exceptional electrical and optical properties of graphene, the proposed tags encoding different bit sequences have a uniform geometric shape and size, which is significant for large-scale fabrication processes. Also, their operating frequency could be independently tuned by altering the doping level of each graphene loop without changing their geometric parameters. Tag principles are revealed by absorption spectra and the physical mechanism is investigated with electric field distributions. In addition, we further evaluate the multilayer graphene-based terahertz identification tag for multi-bit coding application, which breaks the spatial constraints in a single layer. Therefore, the proposed terahertz identification tags based on graphene may have remarkable potential values in future chipless identification applications.
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