5,266 research outputs found
Similarities and differences of functional connectivity in drug-naïve, first-episode adolescent and young adult with major depressive disorder and schizophrenia
Major depressive disorder (MDD) and schizophrenia (SZ) are considered two distinct psychiatric disorders. Yet, they have considerable overlap in symptomatology and clinical features, particularly in the initial phases of illness. The amygdala and prefrontal cortex (PFC) appear to have critical roles in these disorders; however, abnormalities appear to manifest differently. In our study forty-nine drug-naïve, first-episode MDD, 45 drug-naïve, first-episode SZ, and 50 healthy control (HC) participants from 13 to 30 years old underwent resting-state functional magnetic resonance imaging. Functional connectivity (FC) between the amygdala and PFC was compared among the three groups. Significant differences in FC were observed between the amygdala and ventral PFC (VPFC), dorsolateral PFC (DLPFC), and dorsal anterior cingulated cortex (dACC) among the three groups. Further analyses demonstrated that MDD showed decreased amygdala-VPFC FC and SZ had reductions in amygdala-dACC FC. Both the diagnostic groups had significantly decreased amygdala-DLPFC FC. These indicate abnormalities in amygdala-PFC FC and further support the importance of the interaction between the amygdala and PFC in adolescents and young adults with these disorders. Additionally, the alterations in amygdala-PFC FC may underlie the initial similarities observed between MDD and SZ and suggest potential markers of differentiation between the disorders at first onset
Nucleon-nucleon interaction in the - coupled channel for a pion mass of 469 MeV
In this work, we apply the relativistic chiral nuclear force to describe the
state-of-the-art lattice simulations of the nucleon-nucleon scattering
amplitude. In particular, we focus on the - coupled channel for a
pion mass of 469 MeV. We show that at leading order the relativistic chiral
nuclear force can only describe and up to
MeV, while at the next-to-leading order it can do
much better up to MeV. However, at the
next-to-next-to-leading order, the description deteriorates, which can be
attributed to the fact that the pion-mass dependence of the pion-nucleon
couplings may not be negligible. Furthermore, all the studies
consistently yield negative , contrary to the lattice QCD results
which are positive but consistent with zero. The present study is relevant to a
better understanding of the lattice QCD nucleon-nucleon force and more general
baryon-baryon interactions.Comment: Accepted for publication in PL
An integrated geophysical approach for investigating hydro-geological characteristics of a debris landslide in the Wenchuan Earthquake area
Debris landslides are one of the most widely distributed types of landslides in the Wenchuan earthquake area. The hydro-geological structure characteristics are the fundamental basis for stability evaluation, performing protection and administration of a landslide. The rock and soil mass of a debris landslide was highly non-uniform and preferential seepage paths were normally developed in it. Therefore, in situ identification of the underground water seepage system became particularly important. Recently, investigations on the seepage paths of underground water in debris landslides were restricted to indoor model testing and site observation, which were far from meeting the actual demand for landslide prevention and mitigation. To locate the seepage paths, we conducted survey work on a debris landslide seated in the Xishan Village, Li County, Sichuan Province, China, by combing four different geophysical methods. They were multichannel analysis of surface wave (MASW), electrical resistivity tomography (ERT), ground penetrating radar (GPR) and microtremor survey method (MSM). The geophysical interpretation was verified with field engineering surveys and monitoring data. The results suggested that a dendritic pipe-network seepage system usually developed in debris landslides. Varisized infiltration pipes showed the characteristics of inhomogeneity and concentration of the seepage. This work highlighted that geophysical parameters (shear wave velocity Vs, dielectric constant ε and resistivity value ρ) could provide reliable qualitative and quantitative information about the colluvial layer, bedrock interface, potential sliding surface and underground water seepage system of a landslide. The optimum combination of geophysical methods was suitable to survey the hydro-geological characteristics of debris landslides in the Wenchuan earthquake area
Droplet impact on a heated porous plate above the Leidenfrost temperature: A lattice Boltzmann study
Recently a droplet was observed to form a pancake shape and bounce as it impacted nanotube or micropost surfaces above the Leidenfrost temperature. This led to a significant reduction in droplet contact time. However, this unique bouncing phenomenon is still not fully understood, such as the influence of the plate configuration and the relationship between the droplet rebound time and evaporation mass loss. In this study, we carry out a numerical study of the droplet impact dynamics on a heated porous plate above the Leidenfrost temperature, using a multiphase thermal lattice Boltzmann model. Our model is constructed within the unified lattice Boltzmann method (ULBM) framework and is firstly validated based on theoretical and experimental results. Then, a comprehensive parametric study is performed to investigate the effects of the impact Weber number, the plate temperature and the plate configurations on the droplet bouncing dynamics. Results show that higher plate temperature, larger Weber number, and smaller pore intervals can accelerate the droplet rebound and promote the droplet pancake bouncing. We demonstrate that the occurrence of the pancake bouncing is attributed to the additional lift force provided by the vapour pressure due to the evaporation of liquid inside the pores. Moreover, the droplet maximum spreading time and maximum spreading factor can be described by a power law function of the impact Weber number. The droplet evaporation mass loss increases linearly with the impingement Weber number and the plate opening fractions
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