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In this paper, we propose a window function design to synthesize beampattern for uniform/sparse rectangular planar array (RPA) with strict constraints on array gain loss to ensure the performance of target detection/tracking, parameter estimation, etc. The array structure under consideration in this work is generated by the Kronecker product of two uniform/sparse linear arrays, thus referred to as RPA-K. In addition to the common symmetric beampatterns, the proposed method is able to synthesize asymmetric beampatterns to enhance interference/clutter suppression in practical scenarios, such as airborne phased array radar (APAR). Rather than designing the beamforming weight vector for each steering direction separately, this work aims to design a window function for multiple steering directions, as a result significantly reducing the computational cost. To design such a window, an iterative alternating optimization algorithm (IAOA) with dynamic allocation of gain loss is proposed to handle the resultant non-convex problem, and its convergence is studied. Compared with directly designing one window function, the proposed method greatly reduces computational complexity by decomposing the window function into two parts. Finally, numerical simulations verify the effectiveness of the proposed window function comparing with the classical adjustable window functions (CAWFs).

To explore the influence of spatially varying ground motion on the dynamic behavior of a train passing through a three-tower cable-stayed bridge, a 3D train–track–bridge coupled model is established for accurately simulating the train–bridge interaction under earthquake excitation, which is made up of a vehicle model built by multi-body dynamics, a track–bridge finite element model, and a 3D rolling wheel–rail contact model. A conditional simulation method, which takes into consideration the wave passage effect, incoherence effect, and site-response effect, is adopted to simulate the spatially varying ground motion under different soil conditions. The multi-time-step method previously proposed by the authors is also adopted to improve computational efficiency. The dynamic responses of the train running on a three-tower cable-stayed bridge are calculated with differing earthquake excitations and train speeds. The results indicate that (1) the earthquake excitation significantly increases the responses of the train–bridge system, but at a design speed, all the running safety indices meet the code requirements; (2) the incoherence and site-response effects should also be considered in the seismic analysis for long-span bridges though there is no fixed pattern for determining their influences; (3) different train speeds that vary the vibration characteristics of the train–bridge system affect the vibration frequencies of the car body and bridge.

Grape white rot, a devastating disease of grapevines caused by Coniella diplodiella(Speg.) Sacc., leads to significant yield losses in grape. Breeding grape cultivars resistant to white rot is essential to reduce the regular use of chemical treatments. In recent years, Chinese grape species have gained more attention for grape breeding due to their high tolerance to various biotic and abiotic factors along with changing climatic conditions. In this study, we employed whole-genome resequencing (WGR) to genotype the parents of ‘Manicure Finger’ (Vitis vinifera, female) and ‘0940’ (Vitis davidii, male), along with 101 F1mapping population individuals, thereby constructing a linkage genetic map. The linkage map contained 9337 single-nucleotide polymorphism (SNP) markers with an average marker distance of 0.3 cM. After 3 years of phenotypic evaluation of the progeny for white rot resistance, we confirmed one stable quantitative trait locus (QTL) for white rot resistance on chromosome 3, explaining up to 17.9% of the phenotypic variation. For this locus, we used RNA-seq to detect candidate gene expression and identified PR1as a candidate gene involved in white rot resistance. Finally, we demonstrated that recombinant PR1 protein could inhibit the growth of C. diplodiellaand that overexpression of PR1in susceptible V. viniferaincreased grape resistance to the pathogen.

Abstract: There are various proposals for the selection of the so-called “objective” or “default” priors in Bayesian analysis. The paper introduces a new criterion, the moment matching criterion, which requires the matching of the posterior mean with the maximum likelihood estimator up to a high order of approximation. A complete characterization of such priors in the one or multi-parameter case is provided. In the process, many new priors are derived. One interesting finding is that even in the absence of nuisance parameters, it is possible to find priors difierent from Jefireys’ prior for a real valued parameter based on our criterion.

Poly(ethylene terephthalate) (PET) fiber has a low moisture regain, which allows it to easily gather static charges, and many investigations have been carried out on this problem. In this study, a series of poly(ethylene terephthalate-co-isophthalate) (PEIT)–poly(ethylene glycol) (PEG) block copolymers were prepared by the incorporation of isophthalic acid (IPA) during esterification and PEG during condensation. PEG afforded PET with an increased moisture affinity, which in turn, promoted the leakage of static charges. However, PET also then became easier to crystallize, even at room temperature, which led to decreased antistatic properties and increased manufacturing inconveniences. IPA was, therefore, used to reduce the crystallinity of the copolymers and, at the same time, make their crystal structure looser for increased water absorption. Moreover, PET fibers with incorporated IPA and PEG showed good dyeability. In this article, the structural characterization of the copolymers and antistatic and mechanical properties of the resulting fibers are discussed. At 4 wt % IPA, the fiber containing 1 mol % PEG with a molecular weight of 1000 considerably improved antistatic properties and other properties. In addition, the use of PEIT–PEG as an antistatic agent blended with PET or modified PET fibers also benefitted the antistatic properties. Moreover, PEIT–PEG could be used with another antistatic agent to produce fibers with a low volume resistance. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 1696–1701, 2003

Background: Mast cells (MCs) have been found to play a critical role during development of inflammatory bowel disease (IBD) that characterized by dysregulation of inflammation and impaired intestinal barrier function. However, the function of MCs in IBD remains to be fully elucidated. Results: In our study, we used exosomes isolated from human mast cells-1 (HMCs-1) to culture with NCM460, HT-29 or CaCO2 of intestinal epithelial cells (IECs) to investigate the communication between MCs and IECs. We found that MCs-derived exosomes significantly increased intestinal epithelial permeability and destroyed intestinal barrier function, which is attributed to exosome-mediated functional miRNAs were transferred from HMCs-1 into IECs, leading to inhibit tight junction-related proteins expression, including tight junction proteins 1 (TJP1, ZO-1), Occludin (OCLN), Claudin 8 (CLDN8). Microarray and bioinformatic analysis have further revealed that a panel of miRNAs target different tight junction-related proteins. Interestingly, miR-223 is enriched in mast cell-derived exosome, which inhibit CLDN8 expression in IECs, while treatment with miR-223 inhibitor in HT-29 cells significantly reversed the inhibitory effect of HMCs-1-derived exosomes on CLDN 8 expression. Most importantly, enrichment of MCs accumulation in intestinal mucosa of patients with IBD compared with those healthy control. Conclusions: These results indicated that enrichment of exosomal miR-223 from HMCs-1 inhibited CLDN8 expression, leading to destroy intestinal barrier function. These finding provided a novel insight of MCs as a new target for therapeutic treatment of IBD.

Background: The aim of the study is to investigate the effects of miR-34a targeted at PAI-1 on urinary microalbumin and renal function in hypertensive mice. Methods: Twenty specific-pathogen-free (SPF) BPN/3J mice were selected in normal group, and 120 SPF BPH/2J mice were evenly divided into model group, negative control group, miR-34a mimic group, miR-34a inhibitor group, Si-PAI-1 group, and miR-34a inhibitor + Si-PAI-1 group. qRT-PCR was used to detect the expression of miR-34a and PAI-1 mRNA. The protein expressions of PAI-1, angiotensin-converting enzyme (ACE) and ACE2 were detected by Western blot. Serum levels of AngII and Ang1-7 were detected by ELISA. Results: miR-34a negatively regulated the expression of PAI-1. Compared with the normal group, mice in the other groups had significantly lower body weight, increased systolic blood pressure and 24-h urinary microalbumin content, decreased miR-34a expression, superoxide dismutase (SOD) and nitric oxide (NO) content, and ACE2 protein expression, and increased PAI-1 expression, serum creatinine (Scr), blood urea nitrogen (BUN) malondialdehyde (MDA), AngII and Ang1-7 levels, and ACE protein expression (all P< 0.05). Compared with the model group, mice in the miR-34a mimic group and Si-PAI-1 group had no significant changes in body weight (all P> 0.05), while they had significantly lower systolic blood pressure and 24-h urinary microalbumin content, increased SOD and NO levels and ACE2 protein expression, and decreased PAI-1 expression, Scr, BUN, MDA, AngII and Ang1-7 levels, and ACE protein expression (all P< 0.05). Compared with the miR-34a inhibitor group, symptoms in miR-34a inhibitor + Si-PAI-1 group were significantly improved (all P< 0.05). Conclusions: miR-34a can inhibit the expression of PAI-1, thereby reducing urinary microalbumin content in hypertensive mice and protecting their renal function.

A design method for the thermoelectric cooling system is improved in this work based on a graphical approach. It is used to select an appropriate thermoelectric cooler (TEC) and determine the value of optimum input current. Theoretical analysis has been conducted to investigate the cooling performance of the system using the design method. Numerical simulation and experimental tests for the entire cooling system validate the calculation result, which indicates the high reliability of the theoretical design method. The temperature dependence of the heat sink resistance and the contact resistance are the major reasons for the small discrepancy. Research is then conducted based on the design method to investigate how a thermoelectric cooling system under natural convection performs, where the optimization of heat sinks at hot side of TEC is done by using the generalized correlations in the previous studies. Comparison is made between the thermoelectric cooling system and the bare-heat-sink system under natural convection. Results show that the thermal resistance of the heat sink attached to TEC is critical to the cooling performance of the whole system. Besides, TEC under natural convection can perform better than the passive cooling if the heat load is not very high (qc″≤20,000 W/m2). The design process and results can provide a useful guidance for other thermal engineers.

Cloud recognition is the base of weather forecast and the recognition of cloud types is challenging because the texture of the clouds is extremely variable under different atmospheric conditions. In this paper, we propose a novel method for ground-based cloud classification. Firstly, the interest operator feature (IO) and the sorted spectral histogram (SSH) feature are generated from Gabor-filtered images and then they are selected by using the principal component analysis (PCA), which can reduce the feature's dimension. Secondly the new training set is selected using the supervised clustering technology. Finally we send the two features to the multi-class SVM classifier, and a voting algorithm is used to determine the category of each cloud. In practice, we find no single feature is best suited for recognizing all these classes. The result shows that this method has higher classfication accuracy and lower space complexity than the other methods.