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Background This study aimed to investigate the clinical application value of chromosome karyotype analysis and union chromosome microarray analysis (CMA) in the prenatal diagnosis of pregnant women with advanced maternal age. Method A total of 228 pregnant women who received invasive prenatal diagnosis due to advanced age in the Medical Genetics Department of Pingxiang Maternal and Child Health Hospital, Jiangxi Province, China from January 2021 to June 2022 were retrospectively analyzed. Results of chromosome karyotype analysis and CMA were compared. Results (1) Chromosome karyotype analysis was performed in 228 elderly pregnant women, among which 213 were normal. Abnormal karyotype was found in 15 cases. (2) Among 228 elderly pregnant women, 211 had normal CMA results and 17 had abnormal CMA results. A total of 32 abnormal cases were detected by chromosome karyotype analysis combined with CMA. (3) A total of 15 cases had abnormal karyotype, only 6 cases had abnormal CMA results, and the coincidence rate of abnormal detection rate of the two methods was 40%.(4) Chromosome inversion, translocation, chimera, and polymorphism were not abnormal in CMA. Conclusion The above two methods had advantages and disadvantages. Karyotype analysis and microarray analysis technology can effectively improve the detection rate of abnormalities in the prenatal diagnosis of older pregnant women. This finding suggested that clinicians should comprehensively analyze various influencing factors, conduct reasonable genetic counseling, and combine the two methods of analysis to improve the detection rate of fetal abnormalities and prevent birth defects in newborns.

Obtaining genetic variation information from indica rice hybrid parents and identification of loci associated with heterosis are important for hybrid rice breeding. Here, we resequence 1,143 indica accessions mostly selected from the parents of superior hybrid rice cultivars of China, identify genetic variations, and perform kinship analysis. We find different hybrid rice crossing patterns between 3- and 2-line superior hybrid lines. By calculating frequencies of parental variation differences (FPVDs), a more direct approach for studying rice heterosis, we identify loci that are linked to heterosis, which include 98 in superior 3-line hybrids and 36 in superior 2-line hybrids. As a proof of concept, we find two accessions harboring a deletion in OsNramp5, a previously reported gene functioning in cadmium absorption, which can be used to mitigate rice grain cadmium levels through hybrid breeding. Resource of indica rice genetic variation reported in this study will be valuable to geneticists and breeders., Hybrid rice cultivars are widely planted around the world. Here, the authors resequence 1,143 indica accessions, focusing on the parents of superior hybrid rice lines in China, and reveal genetic loci that are associated with heterosis via measuring frequency of parental variation difference (FPVD).

To demonstrate the qualifications of the thruster lifetime, performance and reliability design, an 8000-h ground test of a Hall-effect thruster was conducted. Except for the ignition stage, the thruster operated at the nominal condition with a gas flow rate of 53.7 sccm and a discharge current of 4.2 A. In this paper, the research focuses on the evolutions of the thruster performance parameters and plume plasma properties during the long-duration (about 8240 h) test. An optical imaging system was developed to observe the erosion configuration of the insulator rings. The far-field diagnostic instruments consisted of a Langmuir probe, a Faraday probe and a Retarding Potential Analyzer. These probes were configured to measure the local plasma potential, plasma density, ion current density and ion energy. The results show that the thrust value first increases and then decreases during the first 2000 h. At the stage ranging from 2000 to 8240 h, the thrust value shows a slowly rising trend on the whole and stabilizes at the end. The thruster plume exhibits the phenomena of beam expansion and beam contraction at the early-to-mid lifetime stage and the mid-to-late lifetime stage, respectively. During these two periods, the relevant variations of the plume plasma parameters are related to the erosion configuration of the insulator ceramic walls. It also suggests that the evolutions of the thruster performance are largely determined by the properties of the plume plasma, especially the behaviours of the beam ions.

In this letter, it is proposed the hyperspectral image classification method based on the convolutional neural network, which is trained jointly by the reconstruction and discriminative loss functions. In the network, small convolutional kernels are cascaded with the pooling operator to perform feature abstraction, and a decoding channel composed of the deconvolutional and unpooling operators is established. The unsupervised reconstruction, performed by the decoding channel, not only introduces priors to the network training but also is made use to enhance the discriminability of the abstracted features by the control gate. By the experiments, it is shown that the proposed method performs better than the state-of-the-art neural network-based classification methods.

The current situation, hot spot and trend of coronavirus research in public health of China are discussed, which provides reference for the future research and direction of coronavirus. Based on statistical analysis methods such as bibliometric and knowledge mapping, the visual software CiteSpace was used to analyze the knowledge mapping constructed by keywords, clustering, authors and research institutions. Domestic scholars have analyzed and discussed virus tracing, transmission mechanism, virus detection, disease diagnosis and treatment, drug research and development, epidemic situation assessment and other aspects of coronavirus. It has become a trend to use new technologies to improve research and development programs. In addition, traditional Chinese medicine will play an increasingly important role in the future research of coronavirus in public health.

Ligation-mediated PCR (LM-PCR) is a classical method for isolating flanking sequences; however, it has a common limitation of reduced success rate owing to the circularization or multimerization of target restriction fragments including the known sequence. To address this limitation, we developed a novel LM-PCR method, termed Cyclic Digestion and Ligation-Mediated PCR (CDL-PCR). The novelty of this approach involves the design of new adapters that cannot be digested after being ligated with the restriction fragment, and cyclic digestion and ligation may be manipulated to block the circularization or multimerization of the target restriction fragments. Moreover, to improve the generality and flexibility of CDL-PCR, an adapter precursor sequence was designed, which could be digested to prepare 12 different adapters at low cost. Using this method, the flanking sequences of T-DNA insertions were obtained from transgenic rice and Arabidopsis thaliana. The experimental results demonstrated that CDL-PCR is an efficient and flexible method for identifying the flanking sequences in transgenic rice and Arabidopsis thaliana.

It is important and necessary to obtain high-frequency information and texture details in the image reconstruction applications, such as image super-resolution. Hence, it is proposed the multi-scale fusion network (MCFN) in this paper. In the network, three pathways are designed for different receptive fields and scales, which are expected to obtain more texture details. Meanwhile, the local and global residual learning strategies are employed to prevent overfitting and to improve reconstruction quality. Compared with the classic convolutional neural network-based algorithms, the proposed method achieves better numerical and visual effects.

In order to address the impact of large-angle posture changes on face recognition performance, we propose a contour symmetric constraint-generative adversarial network (CSC-GAN) for the multi-pose face recognition. The method employs the convolutional network as the generator for face pose recovery, which introduces the global information of the constrained pose recovery of positive face contour histogram. Meanwhile, the original positive face is used as the discriminator, and the symmetric loss function is added to optimize the learning ability of the network. The positive face with gesture recovery is obtained by striking the balance between training of the generator and discriminator. Then we employed the nearest neighbor classifier to identify. The experimental results show that CSC-GAN obtained good posture reconstruction texture information on the multi-pose face reconstruction. Compared with the traditional deep learning method and 3D method, it also achieves higher recognition rate.

Suggestions on Chinese literature cataloging of Mainland, Taiwan, Hong Kong and Macao are put forward, with a view to achieving world-wide sharing of Chinese bibliographic metadata. Cataloging rules and MARC format of Chinese literatures are compared in four places of China. The respective characteristics and the present situation are analyzed. According to the analysis results, CNMRAC, CMARC and MARC21 have their own advantages and disadvantages. A unified resource description framework is needed for the processing of Chinese literature cataloging. BIBFRAME is a more suitable unified resource description framework which needs further research and efforts to adapt to Chinese literatures in digital library.

Sulfotransferases (SOTs; EC 2.8.2.-), which are widespread from prokaryotes to eukaryotes, constitute a multi-protein family that plays crucial roles in plant growth, development and stress adaptation. However, this family has not been systemically investigated in Brassica rapa. Here, a genome-wide systemic analysis of SOT genes in B. rapa subsp. pekinensis, a globally cultivated vegetable, were conducted. We identified 56 SOT genes from the whole B. rapa genome using Arabidopsis SOT sequences as queries and classified them into nine groups, rather than the eight groups of previous research. 56 B. rapa SOT genes (BraSOTs) were distributed on all 10 chromosomes except for chromosome 5. Of these, 27 BraSOTs were distributed in seven clusters on five chromosomes (ChrA01, ChrA02, Chr03, ChrA07, and Chr09). Among the BraSOT proteins, 48 had only one SOT_1 domain and 6 had two, while 2 had one SOT_3 domain. Additionally, 47 BraSOT proteins contained only known SOT domains. The remaining nine proteins, five in group-VIII and two in group-IX, contained additional transmembrane domains. Specific motif regions I and IV for 3'-phosphoadenosine 5'-phosphosulfate binding were found in 41 BraSOT proteins. Introns were present in only 18 BraSOT genes, and all seven BraSOT genes in groups VIII and IX had more than three introns. To identify crucial SOTs mediating the response to abiotic stress in B. rapa, expression changes in 56 BraSOT genes were determined by quantitative RT-PCR after drought, salinity, and ABA treatments, and some BraSOT genes were associated with NaCl, drought and ABA stress, e.g. Bra017370, Bra009300, Bra027880.

To improve the accuracy in low resolution face recognition, a method based on super-resolution joint feature mapping is proposed. Firstly, a two-branch convolutional neural network is designed to extract features of high and low resolution face images. A super-resolution enhanced network cascading feature extraction network is used for feature mapping of low resolution face images. In this way, the high frequency information of low resolution image can be reconstructed, and features are extracted. Secondly, a fusion loss method is utilized, in which the loss of cosine and the image reconstruction are weighted and fusioned to increase the cosine similarity between image features of different resolutions. Finally, the experimental results based on FERET dataset validate that the test accuracy of two-branch framework is up to 98.2%, 99.1%, 99.5% with resolutions of 20× 20, 24× 24, and 36× 36 obtained by smooth downsampling. The proposed model outperforms up-to-date low resolution face recognition methods.

The standard binary enzymatic assembly, which operates by inserting one DNA fragment into a plasmid, has a higher assembly success rate than the polynary enzymatic assembly, which inserts two or more fragments into the plasmid. However, it often leaves a nucleotide scar at the junction site. When a large DNA molecule is assembled stepwise into a backbone plasmid in a random piecewise manner, the scars will damage the structure of the original DNA sequence in the final assembled plasmids. Here, we propose an in vitro Seamless Stack Enzymatic Assembly (SSEA) method, a novel binary enzymatic assembly method involving a seamless strategy of splicing restriction sites via a stepwise process of multiple enzymatic reactions that does not leave nucleotide scars at the junction sites. We have demonstrated the success and versatility of this method through the assembly of 1) a 4.98 kb DNA molecule in the 5′ → 3′ direction using BamHI to generate the sticky end of the assembly entrance, 2) a 7.09 kb DNA molecule in the 3′ → 5′ direction using SmaI to generate the blunt end of the assembly entrance, and 3) an 11.88 kb DNA molecule by changing the assembly entrance.

Panicle traits are among the most important agronomic characters which directly relate to yield in rice. Grain number (GN), panicle length (PL), primary branch number (PBN), and secondary branch number (SBN) are the major components of rice panicle structure, and are all controlled by quantitative trait loci (QTLs). In our research, four advanced backcross overlapping populations (BIL152, BIL196a, BIL196b, and BIL196b-156) carrying introgressed segments from chromosome 6 were derived from an indica/japonica cross that used the super-hybrid rice restorer line HR1128 and the international sequenced japonica cultivar 'Nipponbare' as the donor and recurrent parents, respectively. The four panicle traits, GN, PL, PBN, and SBN, were evaluated for QTL effects using the inclusive composite interval mapping (ICIM) method in populations over two years at two sites. Results showed that a total of twelve QTLs for GN, PL, PBN, and SBN were detected on chromosome 6. Based on marker loci physical positions, the QTLs were found to be tightly linked to three important chromosomal intervals described as RM7213 to RM19962, RM20000 to RM20210, and RM412 to RM20595. Three QTLs identified in this study, PL6-5, PBN6-1, and PBN6-2, were found to be novel compared with previous studies. A major QTL (PL6-5) for panicle length was detected in all four populations at two locations, and its position was narrowed down to a 1.3Mb region on chromosome 6. Near isogenic lines (NILs) carrying PL6-5 will be developed for fine mapping of the QTL, and our results will provide referable information for gene excavation of panicle components in rice.

This paper proposes an improved method for feature selection based on traditional mutual information by establishing domain feature words which utilize the differences in the representation of a word in different classes. By the method, we can reselect the feature set out of the established one based on the traditional mutual information. It not only reduces the dimension of the vector but also represents the text more effectively. At the same time, a text similarity calculation system is designed in this paper. Finally, the experimental results show that the improved feature extraction method is superior to the traditional mutual information and the system has a good performance.

There are various non-invasive methods in skin morphology for assessing skin aging. The use of digital photography will make it easier and more convenient. In this study, we explored some skin texture parameters for evaluating skin aging using digital image processing.Two hundred and twenty-eight subjects who lived in Sanya, China, were involved. Individual sun exposure history and other factors influencing skin aging were collected by a questionnaire. Meanwhile, we took photos of their dorsal hands. Skin images were graded according to the Beagley-Gibson system. These skin images were also processed using image analysis software. Five skin texture parameters, Angle Num., Angle Max., Angle Diff., Distance and Grids, were produced in reference to the Beagley-Gibson system.All texture parameters were significantly associated with the Beagley-Gibson score. Among the parameters, the distance between primary lines (Distance) and the value of angle formed by intersection textures (Angle Max., Angle Diff.) were positively associated with the Beagley-Gibson score. However, there was a negative correlation between the number of grids (Grids), the number of angle (Angle Num.) and the Beagley-Gibson score. These texture parameters were also correlated with factors influencing skin aging such as sun exposure, age, smoking, drinking and body mass index. In multivariate analysis, Grids and Distance were mainly affected by age. But Angle Max. and Angle Diff. were mainly affected by sun exposure.It seemed that the skin surface morphologic parameters presented in our study reflect skin aging changes to some extent and could be used to describe skin aging using digital image processing.

Resilient Packet Ring (RPR) is the metropolitan area network (MAN) architecture of based on optimization of packet service, its ring fabric is the part of register insert ring. Register insert ring has the characteristics of time-division multiplexing and space-division multiplexing, and the schedule of ring fabric is simple. It is suitable for fabric of switch. The article uses register insert ring for ring fabric, and models the structure of ring switching according to queuing theory and analyses its performance. The results show that the structure of register insertion ring is suitable for high- speed packet switching.

Automatic detection of an unusual event in video sequence has an interesting application in security surveillance. This paper proposed a method to detect a gathering event without tracking individuals by using background subtracted blobs as the event feature and dividing the video frame into blocks. The feature sequences are encoded with hidden markov model to detect the gathering event. The experimental results show the effectiveness of the proposed approach.

To resist various attacks, a Boolean function used in symmetric cipher systems should satisfy multiple cryptographic criteria. In this paper, a new generalized construction method for Boolean functions which satisfy multiple cryptographic criteria is provided. These multiple cryptographic criteria include balanced, high nonlinearity, high algebraic degree, propagation criterion of order l (PC(l)) and nonexistence of nonzero linear structures. The construction is based on the use of linear error-correcting code. Given a linear code and its dual code, we show that it is possible to obtain these cryptographic functions.

Dempster-Shafer (D-S) evidence theory is an effective method used for Distributed Decision Fusion (DDF). However, constructing a basic probability assignment function (BPAF) is a challenging task for practical fusion applications. This paper proposes a novel method for DDF of target identification. In the presented algorithm, Support Vector Machine (SVM) is utilized as the identifier, and the basic probability assignment function is constructed accordingly. The final fused results are obtained by applying the D-S evidence theory to the outputs of the identifiers. The experimental results show that the proposed method provides higher accuracy and reliability when it is compared with existing voting schemes.

Efficient image segmentation is the first step towards object- and content-based video applications. Tracking of segmented regions (blobs) is even more important and challenging due to abrupt object motion, nonrigid shape distortion, object and scene occlusions, and camera motion. This paper proposes a novel system for automatic and efficient color blob segmentation in image spatial domain and fast arbitrary-shape blob tracking in video sequences. Firstly, a dual-threshold connected component labeling (CCL) algorithm is proposed for efficient blob extraction in grey scale images. Then an unsupervised image segmentation method is designed using the CCL and meanshift principle. With the blob information obtained from the image segmentation procedure, each pixel within a color region is then assigned a region index number which is linked with two blob parameters: the size and the average color intensity. To track an arbitrary-shape blob through a video sequence, a novel algorithm based on region index map (RIM) is employed instead of using traditional motion tracking method to achieve efficient tracking. The experimental results show that the proposed system provides automatic and efficient spatial segmentation. Moreover, robust temporal tracking for fast-moving regions is demonstrated without computationally expensive motion estimation.

One of the key techniques of multi-camera tracking systems is cross-view object tracking. Feature Matching (FM) and Field of View (FOV) based methods are adopted in conventional solutions towards this problem. However, FM is not computationally efficient and the results heavily depend on the parameter settings of the cameras. Therefore, it is not effective in practical applications. In addition, approaches based on FOV suffer from the delay of the detection of newly appeared objects. The results are not reliable if only consistent labelling is utilized. In this paper, we propose a novel scheme for cross-view object tracking based on Projective Invariants (PI) and FM. The experimental results show that, our method improves the performance of normal PI-based tracking algorithms. Especially, it provides accurate tracking performance in the case of multiple objects appear closely in the same area.

The molecular beam epitaxy of self-assembled quantum dots (QDs) has reached a level such that the principal advantages of QD lasers can now be fully realized. We overview the most important recent results achieved to date including excellent device performance of 1.3 μm broad area and ridge waveguide lasers (J th 2 , I th =1.4 mA, differential efficiency above 70%, CW 300 mW single lateral mode operation), suppression of non-linearity of QD lasers, which results to improved beam quality, reduced wavelength chirp and sensitivity to optical feedback. Effect of suppression of side wall recombination in QD lasers is also described. These effects give a possibility to further improve and simplify processing and fabrication of laser modules targeting their cost reduction. Recent realization of 2 mW single mode CW operation of QD VCSEL with all-semiconductor DBR is also presented. Long-wavelength QD lasers are promising candidate for mode-locking lasers for optical computer application. Very recently 1.7-ps-wide pulses at repetition rate of 20 GHz were obtained on mode-locked QD lasers with clear indication of possible shortening of pulse width upon processing optimization. First step of unification of laser technology for telecom range with QD-lasers grown on GaAs has been done. Lasing at 1.5 μm is achieved with threshold current density of 0.8 kA/cm 2 and pulsed output power 7W.

Computer electrocardiography (EGG) is a fundamental diagnostic method for both contour and rhythm analysis. For patients with Hypertrophic Cardiomyopathy (HCM), there are more or less abnormal ECG findings. However, to diagnose HCM through ECG is a difficult task even for experienced cardiologist. Backpropagation has been used for ECG classification with the number of hidden units chosen heuristically. In this paper, the hidden unit number is selected by a new criteria obtained from the so-call Bayesian Ying-Yang learning theory and applied in ECG classification to diagnose HCM. Experiments have shown that the selected number is highly consistent with the minimal generalization error and the corresponding architecture show best classification performance.

We present temperature-dependent measurements of the dephasing time in the ground-state transition of strongly-confined InGaAs quantum dots, using a highly sensitive four-wave mixing technique. At low temperature we measure a dephasing time of several hundred picoseconds. Between 7 and 100 K the polarization decay has two distinct components resulting in a non-Lorentzian lineshape with a sharp zero-phonon line and a broad band from elastic exciton-acoustic phonon interactions. We also explore the dephasing time beyond the one exciton occupation, by electrically injecting carriers. Electrical injection into the barrier region results in a dominantly pure dephasing of the excitonic ground-state transition. Once the injected carriers have filled the electronic ground state, additional filling of the excited states creates multiexcitons that show a fast dephasing due to population relaxation.