We calculate the effective potentials of the ΞcD ( * ) , Ξ cD ( * ) and Ξ * cD ( * ) systems with the chiral effective field theory up to the next-to-leading order. We simultaneously consider the short-, intermediate-and long-range interactions. With the newly observed Pc spectra as inputs, we construct the quark-level contact Lagrangians to relate the low energy constants to those of ΣcD ( * ) with the help of quark model. Our calculation indicates there are seven bound states in the I = 0 strange hidden charm [Ξ cD ( * ) ]J (J = 1 2 , 3 2 ) and [Ξ * cD ( * ) ]J (J = 1 2 , 3 2 , 5 2 ) systems. Our analyses also disfavor the ΛcD ( * ) bound states. However, we obtain three new hadronic molecules in the isoscalar [ΞcD ( * ) ]J (J = 1 2 , 3 2 ) systems. The masses of [ΞcD] 1/2 , [ΞcD * ] 1/2 and [ΞcD * ] 3/2 are predicted to be 4319.4 +2.8 −3.0 MeV, 4456.9 +3.2 −3.3 MeV and 4463.0 +2.8 −3.0 MeV, respectively. We also notice the oneeta-exchange influence is rather feeble. Binding solutions in the I = 1 channels are nonexistent. We hope the future analyses at LHCb can seek for these new Pcss in the JψΛ final states, especially near the thresholds of ΞcD ( * ) .

The newly observed P c (4312), P c (4440) and P c (4457) at the LHCb experiment are very close to the Σ cD and Σ cD * thresholds. In this work, we perform a systematic study and give a complete picture on the interactions between the Σ ( * ) c andD ( * ) systems in the framework of heavy hadron chiral perturbation theory, where the short-range contact interaction, long-range one-pion-exchange contribution, and intermediate-range two-pion-exchange loop diagrams are all considered. We first investigate the three P c states without and with considering the Λ c contribution in the loop diagrams. It is difficult to simultaneously reproduce the three P c s unless the Λ c is included. The coupling between the Σ ( * ) cD ( * ) and Λ cD ( * ) channels is crucial for the formation of these P c s. Our calculation supports the P c (4312), P c (4440) and P c (4457) to be the S-wave hidden-charm [Σ cD ] I=1/2 J=1/2 , [Σ cD * ] I=1/2 J=1/2 and [Σ cD * ] I=1/2 J=3/2 molecular pentaquarks, respectively. Our calculation disfavors the spin assignment J P = 1 2 − for P c (4457) and J P = 3 2 − for P c (4440), because the excessively enhanced spin-spin interaction is unreasonable in the present case. We obtain the complete mass spectra of the [Σ ( * ) cD ( * ) ] J systems with the fixed low energy constants. Our result indicates the existence of the [Σ *cD * ] J (J = 1 2 , 3 2 , 5 2 ) hadronic molecules. The previously reported P c (4380) might be a deeper bound one. Additionally, we also study the hidden-bottom Σ ( * ) b B ( * ) systems, and predict seven bound molecular states, which could serve as a guidance for future experiments. Furthermore, we also examine the heavy quark symmetry breaking effect in the hidden-charm and hidden-bottom systems by taking into account the mass splittings in the propagators of the intermediate states. As expected, the heavy quark symmetry in the bottom cases is better than that in the charmed sectors. We notice that the heavy quark symmetry in the Σ cD and Σ * cD systems is much worse for some fortuitous reasons. The heavy quark symmetry breaking effect is nonnegligible in predicting the effective potentials between the charmed hadrons.

The pseudoscalar tensor states, π 2 , η 2 , and K 2 , are systematically studied through the Okubo-Zweig-Iizukaallowed two-body strong decays, including both the observed states reported by the Particle Data Group and the predicted states. Phenomenological analysis combined with the experimental data not only can test the assignments to these discussed states, but it can also predict more abundant information on their partial decay widths, which is helpful in the experimental study of these observed and predicted pseudotensor states.

The DD * potentials are studied within the framework of heavy meson chiral effective field theory. We have obtained the effective potentials of the DD * system up to O(ǫ 2 ) at one loop level. In addition to the one-pion exchange contribution, the contact and two-pion exchange interactions are also investigated in detail. Furthermore, we have searched for the possible molecular states by solving Schrödinger equation with the potentials. We notice that the contact and two-pion exchange potentials are non-negligible numerically and important for the existence of a bound state. In our results, no bound state is founded in the I = 0 channel within a wide range of cutoff parameter, while there exists a bound state in the I = 1 channel as cutoff is near m ρ in our approach.

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CONTEXT Considerable research has examined reciprocal relationships between parenting, peers and adolescent problem behavior; however, such studies have largely considered the influence of peers and parents separately. It is important to examine simultaneously the relationships between parental monitoring, peer risk involvement and adolescent sexual risk behavior, and whether increases in peer risk involvement and changes in parental monitoring longitudinally predict adolescent sexual risk behavior. METHODS Four waves of sexual behavior data were collected between 2008/2009 and 2011 from high school students aged 13–17 in the Bahamas. Structural equation and latent growth curve modeling were used to examine reciprocal relationships between parental monitoring, perceived peer risk involvement and adolescent sexual risk behavior. RESULTS For both male and female youth, greater perceived peer risk involvement predicted higher sexual risk behavior index scores, and greater parental monitoring predicted lower scores. Reciprocal relationships were found between parental monitoring and sexual risk behavior for males and between perceived peer risk involvement and sexual risk behavior for females. For males, greater sexual risk behavior predicted lower parental monitoring; for females, greater sexual risk behavior predicted higher perceived peer risk involvement. According to latent growth curve models, a higher initial level of parental monitoring predicted decreases in sexual risk behavior, whereas both a higher initial level and a higher growth rate of peer risk involvement predicted increases in sexual risk behavior. CONCLUSION Results highlight the important influence of peer risk involvement on youths’ sexual behavior and gender differences in reciprocal relationships between parental monitoring, peer influence and adolescent sexual risk behavior.

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