485 research outputs found

    Causal SAR ATR with Limited Data via Dual Invariance

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    Synthetic aperture radar automatic target recognition (SAR ATR) with limited data has recently been a hot research topic to enhance weak generalization. Despite many excellent methods being proposed, a fundamental theory is lacked to explain what problem the limited SAR data causes, leading to weak generalization of ATR. In this paper, we establish a causal ATR model demonstrating that noise NN that could be blocked with ample SAR data, becomes a confounder with limited data for recognition. As a result, it has a detrimental causal effect damaging the efficacy of feature XX extracted from SAR images, leading to weak generalization of SAR ATR with limited data. The effect of NN on feature can be estimated and eliminated by using backdoor adjustment to pursue the direct causality between XX and the predicted class YY. However, it is difficult for SAR images to precisely estimate and eliminated the effect of NN on XX. The limited SAR data scarcely powers the majority of existing optimization losses based on empirical risk minimization (ERM), thus making it difficult to effectively eliminate NN's effect. To tackle with difficult estimation and elimination of NN's effect, we propose a dual invariance comprising the inner-class invariant proxy and the noise-invariance loss. Motivated by tackling change with invariance, the inner-class invariant proxy facilitates precise estimation of NN's effect on XX by obtaining accurate invariant features for each class with the limited data. The noise-invariance loss transitions the ERM's data quantity necessity into a need for noise environment annotations, effectively eliminating NN's effect on XX by cleverly applying the previous NN's estimation as the noise environment annotations. Experiments on three benchmark datasets indicate that the proposed method achieves superior performance

    Coupling effects of Fe(II) and CaCO3 application on cadmium uptake and accumulation in rice (Oryza sativa L.)

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    Excessive cadmium (Cd) in rice, caused by Cd pollution of farmlands, poses a serious threat to human health. In this study, a pot experiment was conducted to investigate the effects of two doses of CaCO3 (Ca1: 2 g kg-1, Ca2: 10g kg-1), two types of Fe(II) (EDTA-Fe(II) and FeSO4; 0.14 g Fe kg-1), and their combined application on the uptake and accumulation of Cd in rice plants grown in Cd-contaminated acidic soil. The results revealed that FeSO4 significantly increased rice grain biomass, whereas the other treatments had no significant effects. Further, the addition of EDTA-Fe(II) or FeSO4 significantly enhanced iron plaque formation on the root surface and increased the Fe content in the rice plants and porewater. Compared to the control, CaCO3 addition weakened the formation of iron plaque and reduced the Fe concentration in the porewater and root tissue, stems and leaves, whereas the Fe concentration in brown rice and the husks remained unaffected. Combined application of CaCO3 and Fe(II) significantly promoted the formation of iron plaque and increased the Fe concentration in brown rice. However, the Cd concentration in the iron plaque was reduced by CaCO3 addition but increased by Fe(II) treatment. Notably, all treatments reduced the Cd concentration in all rice plant tissues. The application of Ca1, Ca2, EDTA-Fe(II), FeSO4, Ca1+EDTA-Fe(II), Ca1+FeSO4, Ca2+EDTA-Fe(II) and Ca2+FeSO4 significantly reduced the Cd concentration in brown rice by 69%, 63%, 51%, 60%, 46%, 39%, 38%, and 29%, respectively. These results indicate that the application of CaCO3, EDTA-Fe(II)/FeSO4, or their combination can effectively reduce Cd accumulation and translocation in rice plants

    Chitooligosaccharide enhanced the efficacy of Bacillus amyloliquefaciens CAS02 for the control of tobacco black shank

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    IntroductionTobacco black shank is a devastating soil-borne disease caused by the oomycete Phytophthora nicotianae, severely hamper tobacco production worldwide. However, the synergistic effect of biocontrol bacteria and marine polysaccharides/oligosaccharides on tobacco black shank control was few documented.MethodsIn this study, Bacillus amyloliquefaciens CAS02 (CAS02) and chitooligosaccharide (COS) were screened firstly, and their synergistic antagonistic effect against P. nicotianae and the underlying mechanism were investigated in vitro and in vivo.ResultsIn vitro experiments showed that, compared with the application of CAS02 or COS alone, co-application of CAS02 and COS significantly increased the inhibition rate against P. nicotianae by 11.67% and 63.31%, respectively. Furthermore, co-application of CAS02 and COS disrupted the structure of mycelia to a greater extent. The co-application of CAS02 and COS showed synergistic effect, with the relative control effect maintained above 60% during the 60-day pot experiment, significantly higher than that of application CAS02 or COS alone. The combined application of CAS02 and COS reduced the relative abundance of P. nicotianae in the rhizosphere soil and increased the relative abundance of bacterial taxa potentially involved in disease suppression, such as Nocardioides, Devosia and Bradyrhizobium. Meanwhile, CAS02 and COS synergistically activated salicylic acid (SA), ethylene (ET), and hypersensitive response (HR) defense signaling pathways in tobacco plants.DiscussionOur findings demonstrate that co-application of CAS02 and COS remarkably improve the relative control effect against tobacco black shank through multiple pathways and provide a promising strategy for the efficient green control of tobacco black shank

    Genetic Variation At 8Q24, Family History Of Cancer, And Upper Gastrointestinal Cancers In A Chinese Population

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    Genetic variation at 8q24 is associated with prostate, bladder, breast, colorectal, thyroid, lung, ovarian, UADT, liver and stomach cancers. However, a role for variation at 8q24 in familial clustering of upper gastrointestinal cancers has not been studied. In order to explore potential inherited susceptibility, we analyzed epidemiologic data from a population-based case-control study of upper gastrointestinal cancers from Taixing, China. The study population includes 204 liver, 206 stomach, and 218 esophageal cancer cases and 415 controls. Associations between 8q24 rs1447295, rs16901979, rs6983267 and these cancers were stratified by family history of cancer. Odds ratios and 95% confidence intervals were adjusted for potential confounders: age, sex, education, tobacco smoking, alcohol consumption, and BMI at interview. We also adjusted for hepatitis B and aflatoxin (liver cancer) and Helicobacter pylori (stomach cancer). In a dominant model, among those with a family history of cancer, rs1447295 was positively associated with liver cancer (ORadj 2.80; 95% CI 1.15–6.80). Heterogeneity was observed (Pheterogeneity=0.029) with rs6983267 and liver cancer, with positive association in the dominant model among those with a family history of cancer and positive association in the recessive model among those without a family history of cancer. When considered in a genetic risk score model, each additional 8q24 risk genotype increased the odds of liver cancer by two-fold among those with a family history of cancer (ORadj 2.00; 95% CI 1.15–3.47). These findings suggest that inherited susceptibility to liver cancer may exist in the Taixing population and that variation at 8q24 might be a genetic component of that inherited susceptibility

    Search for the decay J/ψ→γ+invisibleJ/\psi\to\gamma + \rm {invisible}

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    We search for J/ψJ/\psi radiative decays into a weakly interacting neutral particle, namely an invisible particle, using the J/ψJ/\psi produced through the process ψ(3686)→π+π−J/ψ\psi(3686)\to\pi^+\pi^-J/\psi in a data sample of (448.1±2.9)×106(448.1\pm2.9)\times 10^6 ψ(3686)\psi(3686) decays collected by the BESIII detector at BEPCII. No significant signal is observed. Using a modified frequentist method, upper limits on the branching fractions are set under different assumptions of invisible particle masses up to 1.2  GeV/c2\mathrm{\ Ge\kern -0.1em V}/c^2. The upper limit corresponding to an invisible particle with zero mass is 7.0×10−7\times 10^{-7} at the 90\% confidence level

    Search for the reaction e+e−→χcJπ+π− and a charmoniumlike structure decaying to χcJπ± between 4.18 and 4.60 GeV

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    We search for the process e+e-→χcJπ+π- (J=0, 1, 2) and for a charged charmoniumlike state in the χcJπ± subsystem. The search uses datasets collected with the BESIII detector at the BEPCII storage ring at center-of-mass energies between 4.18 GeV and 4.60 GeV. No significant χcJπ+π- signals are observed at any center-of-mass energy, and thus upper limits are provided which also serve as limits for a possible charmoniumlike structure in the invariant χcJπ± mass

    Observation of a structure in e+e−→ϕη′e^+e^- \to \phi \eta^{\prime} at s\sqrt{s} from 2.05 to 3.08 GeV

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    The process e+e−→ϕη′e^{+}e^{-} \to \phi \eta^{\prime} has been studied for the first time in detail using data sample collected with the BESIII detector at the BEPCII collider at center of mass energies from 2.05 to 3.08 GeV. A resonance with quantum numbers JPC=1−−J^{PC}=1^{--} is observed with mass MM = (2177.5 ±\pm 4.8 (stat) ±\pm 19.5 (syst)) MeV/c2{ \it{c}^{\mathrm{2}}} and width Γ\Gamma = (149.0 ±\pm 15.6 (stat) ±\pm 8.9 (syst)) MeV with a statistical significance larger than 10σ\sigma. The observed structure could be identified with the ϕ(2170)\phi(2170), then the ratio of partial width between the ϕη′\phi \eta^{\prime} by BESIII and ϕη\phi \eta by BABAR is (BϕηRΓeeR)/(Bϕη′RΓeeR)\mathcal{B}^{R}_{\phi \eta}\Gamma^{R}_{ee})/{(\mathcal{B}^{R}_{\phi \eta^{\prime}}\Gamma^{R}_{ee})} = 0.23 ±\pm 0.10 (stat) ±\pm 0.18 (syst), which is smaller than the prediction of the ssˉgs\bar{s}g hybrid models by several orders of magnitude
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