A NEW COMPENSATING METHOD FOR THE MU- TUAL COUPLING EFFECT IN ADAPTIVE ANTENNA ARRAYS COMPOSED OF WIRE ELEMENTS

Abstract-A new compensation method for the mutual coupling of adaptive antenna arrays composed of wire elements is introduced. For the antenna array composed of wire elements, the new compensation method can decouple the terminal voltages with high accuracy for both the 1-D incident signals and 2-D incident signals. The new compensation method is based on the mutual coupling grid and the transient mutual coupling coefficient proposed in this paper. By contrast with the CMIM and RMIM, the new compensation method can provide better compensation for the DOA estimations. Even for the ultra compact antenna array and the incident signals inclined with respect to the azimuth the new compensation method can work well. The numerical results verify the validity and the effectiveness of the new compensation method

Psychological resilience and cognitive reappraisal mediate the effects of coping style on the mental health of children

IntroductionThis study explored the effects of coping style and two potential intermediately factors (cognitive reappraisal and psychological resilience) on the mental health of middle school students during the normalization of epidemic prevention and control in China.MethodsAnswers on questionnaires designed to assess coping style, cognitive reappraisal, psychological resilience, and mental health among 743 middle school students (386 boys, 357 girls, 241 first graders, 235 second graders, and 267 third graders) were analyzed using structural equation modeling.ResultsThe results showed that coping style, cognitive reappraisal, and psychological resilience directly predicted mental health. The negative effect of a negative coping style on mental health was significantly stronger than the positive effect of a positive coping style. Coping style affected mental health through the independent mediating effects of cognitive reappraisal and psychological resilience and through their chain mediation.DiscussionThe use of positive coping styles by most students led to greater cognitive reappraisal, strengthened psychological resilience, and thus few mental health problems. These findings provide empirical evidence and may guide educators in the prevention and intervention of mental health problems among middle school students

Compact Multiband Slot Antenna for WLAN/WiMAX Operations

A novel compact triple-band slot antenna is proposed for WLAN/WiMAX applications. With the use of three L-shaped slots and an open-ended slot on the ground plane, three resonant modes centered at 2.4/3.5/5.8 GHz are excited. These modes cover the standards of 3.5 GHz WiMAX and 2.4/5.8 GHz WLAN, three useful frequency bands for present wireless communication systems. The proposed antenna fed by L-shaped microstrip line has a small overall dimension of 16×30 mm2. The numerical and experimental results show that acceptable radiation characteristic is obtained over the operating bands

MICA: a multi-omics method to predict gene regulatory networks in early human embryos

Recent advances in single-cell omics have transformed characterisation of cell types in challenging-to-study biological contexts. In contexts with limited single-cell samples, such as the early human embryo inference of transcription factor-gene regulatory network (GRN) interactions is especially difficult. Here, we assessed application of different linear or non-linear GRN predictions to single-cell simulated and human embryo transcriptome datasets. We also compared how expression normalisation impacts on GRN predictions, finding that transcripts per million reads outperformed alternative methods. GRN inferences were more reproducible using a non-linear method based on mutual information (MI) applied to single-cell transcriptome datasets refined with chromatin accessibility (CA) (called MICA), compared with alternative network prediction methods tested. MICA captures complex non-monotonic dependencies and feedback loops. Using MICA, we generated the first GRN inferences in early human development. MICA predicted co-localisation of the AP-1 transcription factor subunit proto-oncogene JUND and the TFAP2C transcription factor AP-2γ in early human embryos. Overall, our comparative analysis of GRN prediction methods defines a pipeline that can be applied to single-cell multi-omics datasets in especially challenging contexts to infer interactions between transcription factor expression and target gene regulation

Whole-genome sequencing of <em>Oryza brachyantha</em> reveals mechanisms underlying <em>Oryza</em> genome evolution

The wild species of the genus Oryza contain a largely untapped reservoir of agronomically important genes for rice improvement. Here we report the 261-Mb de novo assembled genome sequence of Oryza brachyantha. Low activity of long-terminal repeat retrotransposons and massive internal deletions of ancient long-terminal repeat elements lead to the compact genome of Oryza brachyantha. We model 32,038 protein-coding genes in the Oryza brachyantha genome, of which only 70% are located in collinear positions in comparison with the rice genome. Analysing breakpoints of non-collinear genes suggests that double-strand break repair through non-homologous end joining has an important role in gene movement and erosion of collinearity in the Oryza genomes. Transition of euchromatin to heterochromatin in the rice genome is accompanied by segmental and tandem duplications, further expanded by transposable element insertions. The high-quality reference genome sequence of Oryza brachyantha provides an important resource for functional and evolutionary studies in the genus Oryza

Accurate DOA Estimations Using Microstrip Adaptive Arrays in the Presence of Mutual Coupling Effect

A new mutual coupling calibration method is proposed for adaptive antenna arrays and is employed in the DOA estimations to calibrate the received signals. The new method is developed via the transformation between the embedded element patterns and the isolated element patterns. The new method is characterized by the wide adaptability of element structures such as dipole arrays and microstrip arrays. Additionally, the new method is suitable not only for the linear polarization but also for the circular polarization. It is shown that accurate calibration of the mutual coupling can be obtained for the incident signals in the 3 dB beam width and the wider angle range, and, consequently, accurate [1D] and [2D] DOA estimations can be obtained. Effectiveness of the new calibration method is verified by a linearly polarized microstrip ULA, a circularly polarized microstrip ULA, and a circularly polarized microstrip UCA

Effect of β-crystals on the mechanical and electrical properties of β-nucleated isotactic polypropylene

Polypropylene has great potential as a thermoplastic insulation material for high voltage direct current (HVDC) cable. However, its mechanical properties restrict its application, particularly at low temperature. In this paper, isotactic polypropylene (iPP) with the β-nucleating agent WBG was prepared by the melt blending method. The crystallinity, β-crystal proportion and crystalline morphology were analyzed by wide-angle X-ray diffraction, differential scanning calorimetry, scanning electron microscopy and polarized optical microscopy. The results showed that the crystallinity and β-crystal proportion increased as the WBG concentration increased. Three types of β-crystal morphology, namely β-spherulite, flower-like agglomerate and β-quasi-spherulite, were sequentially obtained with increasing WBG concentration. The mechanical properties, space charge distribution, thermally stimulated discharge current and DC electrical breakdown strength were investigated. Compared with pure iPP, the Izod impact strength and DC breakdown strength of iPP/0.1%WBG were improved by 238 and 16%, respectively, and the fracture energy and brittleness temperature of iPP/0.3%WBG were improved by 420 and 80%, respectively. In addition, the space charge accumulation was suppressed in the range of 0.1-0.5 wt% WBG. Chain coupling between the β-crystals and the amorphous phase, particularly in the flower-like agglomerates, was considered to play an important role in improving the mechanical and electrical performance.</p