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The ancient Silk Road served as the main connection between East and West Eurasia for several centuries. At any rate, the genetic exchange between populations along the ancient Silk Road was likely to leave traces on the contemporary gene pool of local people in Northwest China, which was the passage of the Northern Silk Road. However, genetic sources from northwestern China are under-represented in the current population-scale genomic database. To characterize the genetic architecture and adaptative history of the Northern Silk Road ethnic populations, we performed whole-genome sequencing on 126 individuals from six ethnolinguistic groups (Tibeto-Burman (TB)-speaking Tibetan, Mongolic (MG)-speaking Dongxiang/Tu/eastern Yugur, and Turkic (TK)-speaking Salar/western Yugur) living in Gansu and Qinghai in the 10K Chinese people Genomic Diversity Project (10K_CPGDP). We observed ethnicity-related differentiated population structures among these geographically close Northwest Chinese populations, that is, Salar and Tu people showed a close affinity with southwestern TB groups, and other studied populations shared more alleles with MG and Tungusic groups. Overall, the patterns of genetic clustering were not consistent with linguistic classifications. We estimated that Dongxiang, Tibetan, and Yugur people inherited more than 10% West Eurasian ancestry, much higher than that of Salar and Tu people (PRIM2, PDE4DIP, NOTCH2, DDAH1, GALNT2, andMLIP) and developmental and neurogenetic diseases (e.g.,NBPFs 8/9/20/25P, etc.). Moreover, theEPAS1gene, a transcription factor regulating hypoxia response, showed relatively high PBS values in our studied groups. The sex-biased admixture history, in which the West Eurasian ancestry was introduced primarily by males, was identified in Dongxiang, Tibetan, and Yugur populations. We determined that the eastern-western admixture occurred ∼783–1131 years ago, coinciding with the intensive economic and cultural exchanges during the historic Trans-Eurasian cultural exchange era.

BackgroundThe underrepresentation of Hmong-Mien (HM) people in Asian genomic studies has hindered our comprehensive understanding of population history and human health. South China is an ethnolinguistically diverse region and indigenously settled by ethnolinguistically diverse HM, Austroasiatic (AA), Tai-Kadai (TK), Austronesian (AN), and Sino-Tibetan (ST) people, which is regarded as East Asia’s initial cradle of biodiversity. However, previous fragmented genetic studies have only presented a fraction of the landscape of genetic diversity in this region, especially the lack of haplotype-based genomic resources. The deep characterization of demographic history and natural-selection-relevant architecture in HM people was necessary.ResultsWe comprehensively reported the population-specific genomic resources and explored the fine-scale genetic structure and adaptative features inferred from the high-density SNP data in 440 individuals from 34 ethnolinguistic populations, including previously unreported She. We identified solid genetic differentiation between inland (Miao/Yao) and coastal (She) southern Chinese HM people, and the latter obtained more gene flow from northern East Asians. Multiple admixture models further confirmed that extensive gene flow from surrounding ST, TK, and AN people entangled in forming the gene pool of coastal southeastern East Asian HM people. Population genetic findings of isolated shared unique ancestral components based on the sharing alleles and haplotypes deconstructed that HM people from Yungui Plateau carried the breadth of genomic diversity and previously unknown genetic features. We identified a direct and recent genetic connection between Chinese and Southeast Asian HM people as they shared the most extended IBD fragments, supporting the long-distance migration hypothesis. Uniparental phylogenetic topology and Network relationship reconstruction found ancient uniparental lineages in southwestern HM people. Finally, the population-specific biological adaptation study identified the shared and differentiated natural-selection signatures among inland and coastal HM people associated with physical features and immune function. The allele frequency spectrum (AFS) of clinical cancer susceptibility alleles and pharmacogenomic genes showed significant differences between HM and northern Chinese people.ConclusionsOur extensive genetic evidence combined with the historic documents supported the view that ancient HM people originated in Yungui regions associated with ancient ‘Three-Miao tribes’ descended from the ancient Daxi-Qujialing-Shijiahe people. And then, some recently rapidly migrated to Southeast Asia, and some culturally dispersed eastward and mixed respectively with Southeast Asian indigenes, coastal Liangzhu-related ancient populations, and incoming southward Sino-Tibetan people. Generally, complex population migration, admixture, and adaptation history contributed to their specific patterns of non-coding or disease-related genetic variations.

Non-recombining regions of the Y-chromosome are inherited male-specifically and recorded the evolutionary traces of male human populations. Recent whole Y-chromosome sequencing studies have identified previously unrecognized population divergence, expansion and admixture processes, which promotes a better understanding and application of the observed patterns of Y-chromosome genetic diversity. Here, we developed one highest-resolution Y-SNP panel for forensic pedigree search and paternal biogeographical ancestry inference, which included 639 phylogenetically informative SNPs (Y-SNPs). We genotyped these loci in 1033 Chinese male individuals from 33 ethnolinguistically diverse populations and identified 257 terminal Y-chromosomal lineages with frequency ranging from 0.010 (singleton) to 0.0687. We identified six dominant common founding lineages associated with different ethnolinguistic backgrounds, which included O2a2b1a1a1a1a1a1a1-M6539, O2a1b1a1a1a1a1a1-F17, O2a2b1a1a1a1a1b1a1b-MF15397, O2a2b2a1b1-A16609, O1b1a1a1a1b2a1a1-F2517 and O2a2b1a1a1a1a1a1-F155. The AMOVA and nucleotide diversity estimates revealed considerable differences and high genetic diversity among ethnolinguistically different populations. We constructed one representative phylogenetic tree among 33 studied populations based on the haplogroup frequency spectrum and sequence variations. Clustering patterns in principal component analysis and multidimensional scaling results showed a genetic differentiation between Tai-Kadai-speaking Li, Mongolic-speaking Mongolian and other Sinitic-speaking Han Chinese populations. Phylogenetic topology inferred from the BEAST and Network relationships reconstructed from the popART further showed the founding lineages from culturally/linguistically diverse populations, such as C2a/C2b was dominant in Mongolian people and O1a/O1b was dominant in island Li people. We also identified many lineages shared by more than two ethnolinguistically different populations with a high proportion, suggesting their extensive admixture and migration history. Our findings indicated that our developed high-resolution Y-SNP panel included major dominant Y-lineages of Chinese populations from different ethnic groups and geographical regions, which can be used as the primary and powerful tool for forensic practice. We should emphasize the necessity and importance of whole-sequencing of more ethnolinguistically different populations, which can help identify more unrecognized population-specific variations for the final promotion of Y-chromosome-based forensic applications.

Designing a novel photocatalytic composite for the efficient degradation of organic dyes remains a serious challenge. Herein, the multi-layered Co

It is difficult to find the hidden danger or defect of substation equipment accurately and quickly when the substation equipment is inspected manually. In this paper, an electric inspection robot equipped with ultraviolet camera was studied. The dual-light image detection module of visible and ultraviolet camera was built on the robot's head. The effect of air pressure on the results of ultraviolet imaging was studied experimentally. The results show that with the increase of air pressure, the spot area decreases obviously, and the corona discharge weakens. Robot patrol inspection equipped with ultraviolet camera is helpful to realize non-contact live detection, which is of great significance to improve the intelligent detection level of substation.

Insulator is one of the most widely used components in the power grid. Identifing and locating insulator accurately and efficiently is the basis of intelligent evaluation of insulator defects based on UV imaging. The traditional insulator identification and location is mostly done by the back-end server, which has poor real-time performance. Based on this, this paper proposes an insulator intelligent recognition method based on machine vision and edge calculation, builds an edge calculation platform and loads the labeled insulator data set into SSD model for training. The accuracy of recognition is 91.46% and the model file is transplanted to the edge device. At the same time, the edge equipment is equipped with a visual sensor, which can identify the real-time video stream of the insulator. It has a good real-time performance and provides a new scheme for the fault detection of the external insulation equipment.

It is a great challenge to explore a feasible inner factor that dominates the ligament/pore size of nanoporous metals (NPMs). Herein, the controllable nanoporous copper (NPC) ribbons synthesized by free-dealloying as-spun Cu50-xZr50Mx (x = 0 and 2.5 at.%; M = Al, Nb, Ag) metallic glasses (MGs). From insightfully understanding the correlation of the ligament sizes of NPC, the surface diffusivity of Cu atoms as well as the corrosion potential of additional elements (Al, Nb, Ag), it is firstly unveiled that the corrosion potential of additional elements in the examined etching media could be an inner factor for influencing the pore/ligament size of NPMs. The new findings rooting in the inherent nature of additional elements makes the design of NPMs with useful pore size much more feasible than ever. For further application of NPC with tunable ligament size, the suitable pore structure of NPC is effective in improving the dispersion of MnO2 nanoflakes or nanoflowers to form 3D porous MnO2@NPC composite electrodes. Density functional theory (DFT) further proves that the interaction of NPC and MnO2 results in the modification of the electronic structure and subsequently the improvement of the electrochemical performance. The NPC-supported MnO2 electrode presents much enhanced specific capacitance and cycling stability as compared to the MnO2 nanoparticles. At last, three symmetric supercapacitor (SC) devices connected in series could power up a green LED bulb for more than 55 min.

A 5G mobile network has evolved from a cell centric radio access network to a user centric one. A user-centric no-cell (UCNC) framework has been proposed, which enables physical layer coordination over a large number of transmission and reception points for each mobile user to always experience cell-center-like communications. This paper presents some key technologies in the UCNC framework. The focus is on proof of concept of UL grant-free transmissions in the UCNC architecture. Massive connectivity supporting a huge number of devices is one of the three important scenarios in 5G networks. The challenges to support massive connectivity lie in the cost of signaling overhead and transmission latency. An uplink grant-free transmission based on sparse code multiple access (SCMA) design is proposed. The proposed scheme can provide different levels of overloading to efficiently meet the massive connectivity requirements. Grant-free transmission conducted in RRC connected state can reduce signaling overhead, while in energy conserved operation (ECO) state, it can significantly reduce the user plane transmission latency. Extensive laboratory testing has been conducted in a collaborative project of Huawei and Telefonica to verify the performance matrices. Taking LTE as a baseline for comparison purposes, it is shown that the signaling overhead by using uplink grant-free transmission can be reduced by around 80% and the user plane transmission latency in ECO state can be reduced by around 93%. Moreover, massive connectivity is efficiently supported with the SCMA scheme that yields around 230% gain over OFDMA in terms of supported active users. pub

A novel honeycomb reflectarray constructed from hexagonal-ring unit is proposed for the generation of convergent orbital angular momentum (OAM) waves. The proposed hexagonal-ring unit is with very succinct structure and a wide operating band, which binds further with the hexagonal lattice and obtain a full-polarization response of the incident wave.

This paper presents a substrate integrated circularly polarized horn antenna based on low temperature cofired ceramic (LTCC) technology. The integrated circularly polarized horn antenna is fed by aperture-coupled strip-line and is obtained with sequential rotation technology. The impedance bandwidth is from 33.426 GHz to 40.446 GHz, and the simulated gain is about 10.2 dB at 35 GHz. The simulated results show that this circularly polarized antenna has good axial ratio with the working bandwidth, and the size is smaller than the traditional horn antenna. The proposed circularly polarized horn antenna could be applied into the wireless communications or satellite systems.

Technological development provides industries and spheres with numerous benefits, particularly availability of new progressive methods that contribute to increase efficiency and enhance performance. Thus, machine learning methods may contribute to financial industry that is involved in processing of a large volume of data. Machine learning methods facilitate to process data faster and efficiently with the minimal intervention of humans. In addition, it helps topredict possible risks for financial business and minimize risks related to the fraudulent activity or financial losses. Furthermore, application of machine learning methods contributes to enhance the work with clients and targeted groups, as well as provide them with appropriate services. The major risks of machine learning methods applications within the financial sphere relate to unpredictability and cyber security issues.

The impedance characteristic of folded-waveguide (FW) slow-wave structure (SWS) is studied in this paper. The impedance parameters are determined by the high-frequency parameters, especially the digital electromagnetic field data from a high-frequency structure simulator. After the analysis of the gap impedance of different radii and different angles, the formula of interaction impedance is presented. Finally, the coupling impedance is studied and compared with the interaction impedance. The method can be applied to other complex SWSs that lack of effective analytical methods.

THz wave propagation properties in a magnetized thermal plasma is researched in this paper. In the plasma, the electron density as well as the collision frequency are supposed to be Gaussian function. The non-uniform plasma is treated as a number of subslabs in which the electron density remains constant. The temperature of plasma, as well as the magnetic field, is considered. Particularly, twice reflection in each subslab is introduced. The absorbed and transmitted power ratios are simulated.

A dual-polarized transmit-array lens (TAL) is presented for the generation of dual-mode convergent orbital angular momentum (OAM) beams in C-band. The proposed TAL consists of dual-polarized metamaterial unit cells, which are composed of four stacked patches coupled by cross aperture, to complete the phase correction for both polarizations and stimulate the dual-mode convergent OAM beams. The simulated results verify the effectiveness of the proposed design.

An electronically reconfigurable unit cell with 1-bit phase resolution (0°/180°) is presented for programable transmit-array lens (TAL) in C-band. The I-bit phase resolution is obtained by using two PIN diodes integrated in the transmitting layer of the unit cell. The simulated results verify that the proposed unit can achieve good 1-bit phase tuning, with minimum insertion loss of 0.2 dB and 2-dB transmission bandwidth of about 10%.

A novel hexagonal metamaterial unit cell is presented to construct the honeycomb transmit-array lens (TAL) generating the convergent orbital angular momentum (OAM) beams in C-band. Compared with the most common square-lattice arrays, the proposed honeycomb TAL can provide a wider operating band, a larger phase-shift range and stable frequency responses as the function of angle and polarization of the incident EM wave. The simulated results verify the effectiveness of the proposed design.

The multi-mode OAM beams generated by a circular phased antenna array are always in divergent directions, which restrict the practical application. To relieve this drawback, the Fabry-Perot (FP) cavity is employed to meliorate the beam orientation, and enhance the directivity of the OAM array. The Fabry-Perot cavity consists of a ground plane, an air cavity and a partially reflecting surface (PRS) composed of periodic complementary circular patches and apertures. The simulated results verify the effectiveness of the proposed design.

A user-centric no-cell (UCNC) framework has been proposed which enables different level coordination over a large number of TRPs. This paper presents some key technologies in UCNC framework with the focus on PoC of UL grant- free transmissions in UCNC architecture. Massive connectivity support is one of the three important scenarios in 5G networks. The challenges to support massive connectivity lie in the cost of signaling overhead and transmission latency. An uplink grant- free transmission based on SCMA (sparse code multiple access) design is proposed. The proposed scheme can provide different levels of overloading to efficiently meet the massive connectiv- ity requirements. Extensive lab tests have been conducted to verify the performance matrices. Taken LTE as a baseline for comparison purpose, it is shown that the signaling overhead by using uplink grant-free transmission can be reduced by around 80% and the user plane transmission latency in ECO state can be reduced by around 93%. Moreover, massive connectivity is efficiently supported with SCMA scheme that yields around 230% gain over OFDMA in terms of supported active users.

We present a preliminary design of a 0.13THz folded-waveguide (FW) traveling-wave-tube amplifier (TWTA). The beam-wave interaction is simulated using a 1-D large signal code, BWISFW-1D, which uses a three-port network representation of the unit cell of the slow wave structures. The simulated output power is in excess of 55W from 128-138GHz, and the maximum efficiency is 4%.

Recently, vortex beam carrying orbital angular momentum (OAM) for radio communications has attracted much attention for its potential of transmitting multiple signals simultaneously at the same frequency, which can be used to increase the channel capacity. However, most of the methods for getting multi-mode OAM radio beams are of complicated structure and very high cost. This paper provides an effective solution of generating dual circularly-polarized (CP) dual-mode OAM beams. The antenna consists of four dual-CP elements which are sequentially rotated 90 degrees in the clockwise direction. Different from all previous published research relating to OAM generation by phased arrays, the four elements are fed with the same phase for both left-hand circular polarization (LHCP) and right-hand circular polarization (RHCP). The dual-mode operation for OAM is achieved through the opposite phase differences generated for LHCP and RHCP, when the dual-CP elements are sequentially rotated in the clockwise direction. The measured results coincide well with the simulated ones, which verified the effectiveness of the proposed design.

Image denoising has been fanatically researched for a very long time in that it is a commonplace yet important subject. The task to testify the performance of different image de-noising methods always resorts to PSNR in the past, until the emergence of SSIM, a landmark image quality assessment (IQA) metric. Since then, a vast majority of IQA methods were introduced in terms of various kinds of models. But unfortunately, those IQA metrics are along with more or less deficiencies such as the requirement of original images, making them far less than the ideal approaches. To address this problem, in this paper we propose an effective and blind image quality assessment for noise (dubbed BIQAN) to approximate the human visual perception to noise. The BIQAN is realized with three important portions, namely the free energy based brain principle, image gradient extraction, and texture masking. We conduct and compare the proposed BIQAN and a large amount of existing IQA metrics on three largest and most popular image quality databases (LIVE, TID2013, CSIQ). Results of experiments prove that the BIQAN has acquired very encouraging performance, outperforming those competitors stated above.