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Stimulated by the proton size puzzle and the proposal of μp scattering at the Paul Scherrer Institute (PSI), we study the two-photon exchange corrections to the massive-lepton-proton scattering. The leptonic helicity broken caused by lepton mass introduces new form factors. We estimate the two-photon exchange corrections to these form factors as well as to the unpolarized differential cross sections. [ABSTRACT FROM AUTHOR]

The discrepancy between the PQCD calculation and the CLEO data for χ→ γ V ( V= ρ, ω, φ) stimulates our interest in exploring other mechanisms of χ decay. In this work, we apply an important non-perturbative QCD effect, i.e., the hadronic loop mechanism, to study χ→ γ V radiative decay. Our numerical result shows that the theoretical results including the hadronic loop contribution and the PQCD calculation of χ→ γ V are consistent with the corresponding CLEO data of χ→ γ V. We expect further experimental measurement of χ→ γ V, which will be helpful to test the hadronic loop effect on χ decay. [ABSTRACT FROM AUTHOR]

Abstract: We estimate the two-photon exchange corrections to both proton and neutron electromagnetic physical observables in a relativistic light cone quark model. At a fixed the corrections are found to be small in magnitudes, but strongly dependent on scattering angle. Our results are comparable to those obtained from simple hadronic model in the medium momentum transfer region. [Copyright &y& Elsevier]

In this paper, we calculate the masses and mixing angles of L=1 negative parity N* resonances in an extended GBE (Goldstone-boson-exchange model) with harmonic-oscillator wave functions. By using those mixing angles, we get their photo-production amplitudes, and compare them with experimental data and the results of OPE (one-pion-exchange model), OPsE (only pseudoscalar meson exchange model), and OGE (one-gluon-exchange model). We find that the extended GBE gives right internal wave functions. It is essential to extend GBE to include not only pseudoscalar meson exchanges but also vector meson exchanges. [Copyright &y& Elsevier]

Based on the duality that both the inelastic and resonance physics languages work for the explanation of nucleon polarized structure functions at moderate Q2, the higher twist effect on nucleon g1 is predicted. [ABSTRACT FROM AUTHOR]

In this paper, the spin-dependent structure functions of nucleon g1, and photoabsorption cross sections σ1/2, σ3/2 and σT in the resonance region are estimated based on the constituent quark model and the properties of the five phenomenological Breit-Wigner resonances P33(1232), S11(1535), D13(1520), P11(1440), and F15(1680). Our results are compared to the recent E143 data of the polarized structure functions g1( W2, Q2) at points Q2=0.5 GeV2 and Q2=1.2 GeV2 and the data of the total inclusive photoabsorption cross sections. [ABSTRACT FROM AUTHOR]

Inspired by recent measurement of possible fully charmed tetraquarks in LHCb Collaboration, we investigate the mass spectra of fully heavy tetraquarks Q Q Q ¯ Q ¯ in an extended relativized quark model. Our estimations indicate that the broad structure around 6.4 GeV should contain one or more ground states for c c c ¯ c ¯ tetraquarks, while the narrow structure near 6.9 GeV can be categorized as the first radial excitation of c c c ¯ c ¯ system. Moreover, with the wave functions of the tetraquarks and mesons, the strong decays of tetraquarks into heavy quarkonium pair are qualitatively discussed, which can be further checked by the LHCb and CMS Collaborations. [ABSTRACT FROM AUTHOR]

Introduction: Atrial natriuretic peptide (ANP) regulates water-salt balance and blood pressure by promoting renal sodium and water excretion., Objective: Our study was to investigate plasma N-terminal pro-atrial natriuretic peptide (NT-proANP) and corin in hypertensive disorders of pregnancy (HDP) patients. Furthermore, the relationship between corin/NT-proANP and neonatal adverse prognosis were evaluated., Methods: Seventy-seven HDP patients and forty-eight normotensive women as control group were recruited. Clinical characteristic and plasma were collected. Plasma NT-proANP and corin were determined by ELISA. Gestational age, neonatal weight and APGAR scores were recorded. Statistical analysis was conducted., Results: NT-proANP and corin were significantly increased in HDP group compared with that of control (P < 0.05). NT-proANP and corin were significantly elevated in HDP patients who suffered from premature delivery (P < 0.05). Both NT-proANP and corin were negatively associated with delivery time, neonatal weight and APGAR scores in HDP group. Multiple regressions demonstrated that NT-proANP and corin were independent risk factor of delivery time, neonatal weight and APGAR scores., Conclusions: Plasma NT-proANP and corin were significantly increased in HDP. NT-proANP and corin were associated with neonatal adverse events in HDP patients. Thus, NT-proANP and corin may become new biomarkers for evaluating severity of pregnancy and neonatal adverse events in HDP patients., (Copyright © 2020 The Author(s). Published by Elsevier B.V. All rights reserved.)

To evaluate the long-term effects of biochar amendment on greenhouse gas emissions (GHGs), a field experiment was conducted to examine the effects of 3-year field-aged biochar (B 3 ) and fresh biochar (B 0 ) on global warming potential (GWP) and greenhouse gas intensity (GHGI) of methane (CH 4 ) and nitrous oxide (N 2 O) in a typical rice-wheat rotation system. Four treatments were established as control without nitrogen fertilizer (CK), urea without biochar (N), urea with fresh biochar amended in 2015 (NB 0 ), and urea with 3-year field-aged biochar amended in 2012 (NB 3 ). Results showed that both the NB 0 and NB 3 treatments obviously increased soil pH, soil organic carbon (SOC), total nitrogen (TN) and influenced the potential activity of functional microorganisms related to GHGs compared to the N treatment. Relative to the N treatment, the NB 3 treatment significantly improved crop yield by 14.1% while reduced the CH 4 and N 2 O emissions by 9.0% and 34.0%, respectively. In addition, the NB 0 treatment significantly improved crop yield by 9.3%, while reduced the N 2 O emission by 38.6% though increased the CH 4 emissions by 4.7% relative to the N treatment. Moreover, both the NB 0 and NB 3 treatments could significantly reduce both GWP and GHGI, with NB 3 being more effective in simultaneously mitigating the GHGs emissions and enhancing crop yield. Since field-aged biochar showed obvious effects on GHGs mitigation and carbon sequestration after 3 years, biochar incorporations had long-term effect on GHGs mitigation and crop production in the rice-wheat rotation system.