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This paper proposes a Scale-consistent Attention Part Network (SCAPNet) to address that issue, which seamlessly integrates three novel modules: grid gate attention unit (gGAU), scale-consistent attention part selection (SCAPS), and part relation modeling (PRM). The gGAU module represents the grid region at a certain fine-scale with middle layer CNN features and produces hard attention maps with the lightweight Gumbel-Max based gate. The SCAPS module utilizes attention to guide part selection across multi-scales and keep the selection scale-consistent. The PRM module utilizes the self-attention mechanism to build the relationship among parts based on their appearance and relative geo-positions. SCAPNet can be learned in an end-to-end way and demonstrates state-of-the-art accuracy on several publicly available fine-grained recognition datasets (CUB-200-2011, FGVC-Aircraft, Veg200, and Fru92).

Catalytic combustion gas sensors have been widely used for the leakage detection of combustible gases. However, the catalytic sensor with low preparation cost and high repeatability in a mass production have great importance. In this view, a new structure of high-performance catalytic sensor was proposed. Catalytic-type gas sensors based on screen-printing Platinum (Pt) heating electrode onto a porous alumina substrate was fabricated. This design enables porous alumina ceramics to act as the support of catalyst and substrate of heating electrode, simultaneously. The screen-printing technique obviously enhance the uniformity of the sensor devices in batch. To demonstrate the feasibility of this design, a prototype hydrogen sensor was prepared with a relatively high sensitivity around 30 mV/Vol% at 245°C and excellent a long-term stability. Additionally, the sensing performances of hydrogen devices were also verified by finite element method (FEM) modeling. The simulation results suggested that the response time and response value were related to the thickness of substrate and the operating temperature of sensors. The facile and large-scale fabrication method of the sensor device in this work is expected to have potential utility for detection in industry and for personalized applications.

The long reaction time and uncontrollable reaction process of the swelling agent in the process of rock breaking by static crushing agent lead to unsatisfactory efficiency and effect of rock breaking. This paper uses physical experiments to compare and analyze the changes in temperature and pressure of the hydration reaction under different microwave conditions; utilizes microscopic analysis of the hydration reaction products under each condition, combined with numerical calculations to elucidate the mechanism of the effect of microwave field on the hydration reaction of the expansion agent; and proposes a microwave field-controlled static crushing agent rock-breaking method. The study reached the following main conclusions: (1) microwave heating is better than conventional heating in terms of heating rate, peak temperature, and peak pressure; (2) using static crushing agent rock breaking is preferable to use a low-power microwave field to control the reaction process, and to ensure that the initial temperature is not higher than the local water boiling point; (3) microwave heating to promote the reaction mechanism lies in its deep heating of the system, faster heating rate, and higher energy utilization, and is more conducive to hydration expansion reaction; (4) selective heating of microwaves can enhance the hydration reaction of calcium oxide and inhibit the production of hydrated tricalcium silicate, making the reaction more complete, while microwave heating will also improve the microstructure of hydration products.

Recommendations promoted worldwide have suggested a period of protection lasting more than 20 years against hepatitis B (HB) following primary immunization. Starting in 1987, universal HB vaccinations were carried out in Long An County, Guangxi Province, one of the earliest counties in which plasma-derived HB vaccine was delivered to newborns across China. Data collection targeted toward understanding the long term (26–33 years since primary immunization) immune effects of the plasma-derived HB vaccine was conducted in 2015; a second data collection was carried out in 2019 to assess seroconversion in the same cohort. This study qualitatively compared positive vs negative results and quantitatively assessed HB biomarkers – HB surface antigen (HBsAg), antibody to HBsAg (anti-HBs), HB e-antigen (HBeAg), antibody to HBeAg (anti-HBe), and antibody to HB core antigen (anti-HBc) – in serum 26–33 years after the full initial course of HB vaccination, then analyzed anti-HBs seroconversion using the two-phase sampling method in the same cohort and calculated the anti-HBs seroconversion rate from 2015 to 2019. The protective sero-conversion rate (anti-HBs ≥10mIU/mL) was 37.6% (192/511); the HBsAg-positive rate was 5.3% (27/511); the anti-HBs mean geometric titer (GMT) was 11.1 mIU/mL. Among the 143 participants involved in both 2015 and 2019 data collections, the seroconversion rate was 3.5% (5/143); two individuals had protective anti-HBs levels in 2015. These findings indicate that anti-HBs status can be seroconverted to a protective concentration level 4 years earlier in a high HBV epidemic region. The role of genomic mutations and the disappearance of immune memory and seroconversion should be investigated.

Various geotechnical experiments have used gypsum-cemented analog geotechnical materials. However, this material needs a long curing time, and the target strength is not easy to control. Therefore, this research adopted microwave heating as the curing method for this kind of material. Objectively, the authors investigated the variations in the material strength versus heating power and heating time. On this basis, we clarified the influence mechanism of microwaves on the strength of analog materials by analyzing material temperature, moisture content, and microstructure, which eventually led to an experimental control method for rapid strengthening of microwave field-controlled gypsum-cemented analog materials. Consequently, we drew the following conclusions. The stable strength of the material under high-power microwave curing was much lower than that under natural curing, while the material strength under low-power microwave curing was the closest to the material under natural curing.

An electronic nose based on metal oxide semiconductor (MOS) sensors has been used to identify liquors with excessive methanol. The technique for a square wave temperature modulated MOS sensor was applied to generate the response patterns and a back-propagation neural network was used for pattern recognition. The parameters of temperature modulation were optimized according to the difference in response features of target gases (methanol and ethanol). Liquors with excessive methanol were qualitatively and quantitatively identified by the neural network. The results showed that our electronic nose system could well identify the liquors with excessive methanol with more than 92% accuracy. This electronic nose based on temperature modulation is a promising portable adjunct to other available techniques for quality assurance of liquors and other alcoholic beverages.

Few-shot action recognition aims to recognize novel action classes (query) using just a few samples (support). The majority of current approaches follow the metric learning paradigm, which learns to compare the similarity between videos. Recently, it has been observed that directly measuring this similarity is not ideal since different action instances may show distinctive temporal distribution, resulting in severe misalignment issues across query and support videos. In this paper, we arrest this problem from two distinct aspects -- action duration misalignment and action evolution misalignment. We address them sequentially through a Two-stage Action Alignment Network (TA2N). The first stage locates the action by learning a temporal affine transform, which warps each video feature to its action duration while dismissing the action-irrelevant feature (e.g. background). Next, the second stage coordinates query feature to match the spatial-temporal action evolution of support by performing temporally rearrange and spatially offset prediction. Extensive experiments on benchmark datasets show the potential of the proposed method in achieving state-of-the-art performance for few-shot action recognition.The code of this project can be found at https://github.com/R00Kie-Liu/TA2N, Published in AAAI 2022

In compressed sensing (CS), the absolute value of the inner product of signal and atom (or dictionary) is used to select atom (or dictionary); the atoms (or dictionaries) with larger absolute values of inner product are selected to decompose and reconstruct signals. This characteristic usually makes it impossible to distinguish the edges of objects (or targets) in some complex cases, especially when the density of objects is very high. For example: let signal x1 = [···00110110···]T, x2 = [⋯001110100⋯]T; ψ1, ψ2, ψ3 and ψ4 denote several sparse basis matrices (i.e., sparse dictionaries); ψ1i = [⋯00000100⋯]T, ψ2j = [⋯00110000⋯]T, ψ3k = [⋯00111000⋯]T, and ψ4l = [⋯00111110⋯]T are the sparse bases (i.e., atoms) from these sparse basis matrices (i.e., dictionaries), respectively. For signal x1, ψ4l (or ψ4) is selected instead of ψ2j (or ψ2); likewise, for x2, ψ4l (or ψ4) will be selected instead of ψ3j(or ψ3) and ψ1i (or ψ1). This causes the edge of the object to be unrecognizable. Another example is in lp regularization, it is not necessarily the optimal case: the smaller the value of ||Ψd-1 x||0, the better the sparse basis matrix (i.e., dictionary), or the larger the weighing parameter. At present, the inner product is used to process almost all signals in CS. Choosing the dictionary that matches the signal best rather than the dictionary with the maximum inner product value can reconstruct the signal more accurately. In order to overcome the above shortcoming, we propose a fully automatic radar image processing algorithm of CS based on arbitrary block statistical histogram and dynamic dictionary. We use arbitrary block statistical histogram to calculate the non-zero block numbers of different sizes, which can better choose the appropriate sparse base (or dictionary) for the signal. Furthermore, the better measurement vector y can be obtained, and the signal can be reconstructed more accurately than the state-of-the-art methods at the receiving end. To realize the proposed method, we construct objective functions and flow charts for noiseless and noisy signals, respectively. In our method, for noiseless signal, discarding the sub-images that do not contain objects can reduce running time; for noisy signal, according to the theory of wavelet, choosing the appropriate wavelet (i.e., wavelet basis) can usually suppress noise. Our proposed algorithm can overcome the above shortcoming of CS in using the absolute value of the inner product, reduce running time, suppress-noise, and improve the signal-to-noise ratio (SNR). The simulation results show that our method is superior to the state-of-the-art methods.

AUX1 and PIN2 auxin transporter are required for the asymmetric distribution of auxin for root gravitropic response. However, the relationship between AUX1 and PIN2 in root gravitropism is unclear. Here, we report that aux1-T mutant show stronger defects in root gravitropism than pin2-T, and aux1-T pin2-T double mutants display similar agravitropic phenotype to aux1-T. The gravity-induced asymmetric distribution of auxin responses could not be established in pin2-T, aux1-T and aux1-T pin2-T mutants; whereas aux1-T pin2-T double mutants showed similar auxin responses to aux1-T mutant. These findings support AUX1 plays a role in root gravitropism upstream of PIN2.

Microwave heating of water-bearing coal can promote pore water evaporation. The pores are broken under the action of steam pressure, increasing the permeability of the coal. This study is aimed at investigating the mechanism of permeability improvement of water-bearing coal rock by microwave steam explosion. First, a microwave oven was used to irradiate and heat five groups of coal rock with different water contents; the NMR test was then conducted on the heated sample. Second, the internal vapor pressure and temperature changes during the heating process were obtained through the T-connector for samples with different water contents. Finally, a numerical experiment was used to explore the deformation characteristics of pores under three filling conditions. The experimental results showed that the total porosity increased significantly when the water content of coal increased from 0% to 8%, while the permeability increased by nearly 4.78 times. The extreme value of gas pressure inside the sample showed an increasing trend. The gas pressure and temperature were in line with the equation of state for an ideal gas during the rising phase. Numerical experiments showed that the pore boundary shrunk inward under vacuum conditions, and compressive stress appeared at the tip. The saturated humid air and liquid water conditions expanded the pore boundaries outward and caused tensile stress at the tip, with the latter being nearly 2.3 times larger than the former, making it more conducive to the development of pores. The findings of this study can be used as a reference value for the expansion of coalbed methane extraction technology.

Background：Traditional Chinese medicines (TCMs) had been proven to stimulate digestion, promote growth, boost immune response, and reduce inflammatory potential in aquaculture, but its action mechanism was still lack of holistic interpretation. Results: The UPLC-Triple-TOF-MS/MS based platform was developed to investigate the serum metabolic profile associated with the growth performance and immunity in Pelodiscus sinensis fed with the diet added with TCMs feeding additive. The final weight and specific growth rate of TG2 groups was significantly the highest (p ˂ 0.05), and the feed conversion ratio of TG2 groups was significantly the lowest (p ˂ 0.05) compared to the CG group. In the metabolomics assay, a total of 795 (VIP > 1) out of 3089 variable ions were significantly different between the TG2 group and CG group. 43 potential biomarkers between TG2 and CG groups were finally screened out on the basis of VIP > 1 and p < 0.05. Based on the analysis of MetPA, eleven potential biomarkers and six involved metabolic pathways were significantly regulated with treatment of TCMs. Phenylalanine, tyrosine and tryptophan biosynthesis and Arginine and proline metabolism were the two most heavily affected pathways (Impact >0.2), while Tyrosine metabolism, Cysteine and methionine metabolism and Arginine biosynthesis were relatively lightly affected pathways. Conclusions：The dietary supplementation nineteen TCMs as feed additives could influence the growth performance of the healthy juvenile P. sinensis, and the optimal dose of TCMs for juvenile turtles was 2% TCMs. The UPLC-Triple-TOF-MS based metabonomics may be a useful tool for elucidating the efficacy and mechanism of complex TCM prescriptions.

Rhamnogalacturonan-II (RG-II) is structurally the most complex glycan in higher plants, containing 13 different sugars and 21 distinct glycosidic linkages. Two monomeric RG-II molecules can form an RG-II-borate diester dimer through the two apiosyl (Api) residues of side chain A to regulate cross-linking of pectin in the cell wall. But the relationship of Api biosynthesis and RG-II dimer is still unclear. In this study we investigated the two homologous UDP-D-apiose/UDP-D-xylose synthases (AXSs) in Arabidopsis thaliana that synthesize UDP-D-apiose (UDP-Api). Both AXSs are ubiquitously expressed, while AXS2 has higher overall expression than AXS1 in the tissues analyzed. The homozygous axs double mutant is lethal, while heterozygous axs1/+ axs2 and axs1 axs2/+ mutants display intermediate phenotypes. The axs1/+ axs2 mutant plants are unable to set seed and die. By contrast, the axs1 axs2/+ mutant plants exhibit loss of shoot and root apical dominance. UDP-Api content in axs1 axs2/+ mutants is decreased by 83%. The cell wall of axs1 axs2/+ mutant plants is thicker and contains less RG-II-borate complex than wild-type Col-0 plants. Taken together, these results provide direct evidence of the importance of AXSs for UDP-Api and RG-II-borate complex formation in plant growth and development.

In order to improve the portability of the automated test of the trunking communication system, this paper proposed a universal automated test solution for the trunking communication system. It’s based on the general architecture design of the trunking communication system, providing a replaceable communication protocol codec module. With the DSL-defined test script language describing the test cases, and efficient scheduling schemes for the test task, the automated functional test and performance test of the trunking communication system are realized. Theoretical analysis and experimental results show that the minimum load test task scheduling scheme based on user operation load prediction has lower response time and lower load balancing effect compared with the traditional static task scheduling scheme.

In order to meet the requirements of lightweight structure design of exoskeleton robot, this paper proposes a T700 carbon fiber exoskeleton leg component based on composite material. By analyzing the function and characteristic of the leg component, a new kind of leg component combined with titanium alloy and T700 carbon fiber was designed. The fatigue performance of the new leg component was tested. The results show that no fatigue failure occurs when the leg component are repeatedly loaded 50 times in the direction of 90° and 45° and the loading force is 2000N. The failure tensile test shows that when the loading load reaches 1700N, fracture failure occurs and the connection interface is destroyed.

In this paper, an adaptive track fusion algorithm is proposed based on the fusion algorithm combining the optimal weighting and recursive least squares method. Simulation results show that the method can effectively improve the accuracy of target detection in longitude, latitude, speed and heading. The ship tracks are more accurate after multi-source information fusion.

Genes essential for gametophyte development and fertilization have been identified and studied in detail; however, genes that fine-tune these processes are largely unknown. Here, we characterized an unknown Arabidopsis gene, GTP-BINDING PROTEIN RELATED1 (GPR1). GPR1 is specifically expressed in ovule, pollen, and pollen tube. Enhanced green fluorescent protein-tagged GPR1 localizes to both nucleus and cytoplasm, and it also presents in punctate and ring-like structures. gpr1 mutants exhibit no defect in gametogenesis and seed setting, except that their pollen grains are pale in color. Scanning electron microscopy analyses revealed a normal patterned but thinner exine on gpr1 pollen surface. This may explain why gpr1 pollen grains are pale. We next examined whether GPR1 mutation affects post gametogenesis processes including pollen germination, pollen tube growth, and ovule senescence. We found that gpr1 pollen grains germinated earlier, and their pollen tubes elongated faster. Emasculation assay revealed that unfertilized gpr1 pistil expressed the senescence marker PBFN1:GUS (GUS: a reporter gene that encodes β-glucuronidase) one-day earlier than the wild type pistil. Consistently, ovules and pollen grains of gpr1 mutants showed lower viability than those of the wild type at 4 to 5 days post anthesis. Together, these data suggest that GPR1 functions as a negative regulator of pollen germination, pollen tube growth, and gametophyte senescence to fine-tune the fertilization process.

Under the guidance of the theory of mantle-branch structure-associated metallogenesis and on the basis of the geological characteristics, analysis of the ore-forming and ore-controlling structures, the geochemical characteristics of metallogenesis, the source of ore-forming materials, changes in the physical and chemical conditions of metallogenesis, changes in the vertical width of ore veins, and changes in gold grade of the Shihu gold deposit, the mechanism of its metallogenesis was discussed and the rules of vertical variation of ore veins were summarized in this study. It is pointed out that the orebodies under exploitation at present time should be in the middle and upper portions of gold veins in the Shihu gold mining district. Particularly on the basis of the characteristics of mantle-branch structure-associated metallogenesis, it is indicated that metallogenesis is controlled mainly by such ore-forming conditions as temperature and pressure. Deep-seated ore-forming fluids are characterized mainly by injection and precipitation. So the vein bodies in the adjacent metallogenic structures are of obvious comparability, and there would be great prospects for ore search both at depth and in the periphery of the Shihu gold deposit. Therefore, ore prospecting should be strengthened both at depth and in the peripheries.

The effects of MO (M Ba, Mg, Ca) on the crystallization of B2O3–Al2O3–SiO2 glass-ceramics were investigated by means of differential scanning calorimetry (DSC), X-ray diffraction (XRD), scanning electron microscopy (SEM) and dilatometer. MO can effectively facilitate the formation of B2O3–Al2O3–SiO2 glass which is influenced by the ratio of B2O3/SiO2, and the crystallization capacity of the glass turns to weaker with the decreasing of B2O3/SiO2 ratio. The main crystal phase is Al4B2O9 when the glass is heat-treated at 800 °C, and Al4B2O9 phase could transfer into Al18B4O33 with the heat-treated temperature increasing to 1100 °C. The calculation of crystallization activation energy (E) shows that crystallinity follows the order of CaO

Adsorption of poly(ethylene oxide) (PEO) with different molecular weights ( Mws ) in aqueous suspension on the surface of silica nanoparticles and the stability of suspension dispersion were studied. Adsorption isotherms demonstrate that the plateau-adsorbed amount of polymer is related to Mw . Results of infrared analysis indicate that PEO is adsorbed on silica through a hydrogen bonding between –SiOH and ether oxygen of PEO molecule. The change in | ζ | of silica suspensions after adsorption varies distinctly with different Mw , and the main factors responsible for the changes and the stability mechanisms of suspension were discussed. Using the appropriate Mw PEO, a highly stabilized dispersion can be achieved at a certain concentration.