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In heavy-ion collisions at intermediate energies, the production and propagation of Δ particles are crucial to understanding the nuclear equation of state and inferring the properties of nuclear matter at high densities. Based on the self-consistent relativistic Boltzmann-Uehling-Uhlenbeck (RBUU) transport theory, by introducing the isovector ρ meson exchange into the effective Lagrangian and adopting the density-dependent coupling constants, the detailed expressions for isospin-dependent in-medium N Δ → N Δ elastic cross sections σ N Δ ∗ have been calculated. The energy and density dependence of the isospin-related σ N Δ ∗ as well as the total contributions of σ , ω and ρ meson fields are analyzed. It is found that the total σ N Δ ∗ has a sensitive center-of-mass energy dependence at lower energies while exhibiting a slight increase as the center-of-mass energy increases. The isospin effect between different isospin-separated channels weakens as the energy and/or density increases. The isospin effect on the density- and energy-dependent in-medium N Δ elastic cross sections is dominantly caused by the delicate balance of the isovector ρ meson exchange. [ABSTRACT FROM AUTHOR]

The Heavy Ion Research Facility in Lanzhou-Cooling Storage Ring (HIRFL-CSR) external-target experiment (CEE) under construction is expected to provide novel opportunities for the studies of the thermodynamic properties of nuclear matter, in particular the nuclear matter equation of state (nEOS), with heavy ion collisions at a few hundreds MeV/u beam energies. Based on Geant 4 packages, the simulations of the detector responses to the collision events generated using transport model are conducted. The overall performance of CEE, including the geometric coverage, the momentum resolution of tracks and the particle identification ability has been investigated. Various observables proposed to probe the nEOS, such as the production of light clusters, 3 H / 3 He yield ratio, radial flow, π - / π + yield ratio and neutral kaon yields, have been reconstructed. The feasibility of studying nEOS beyond the saturation density via the aforementioned observables to be measured with CEE has been demonstrated by using the ultra relativistic quantum molecular dynamics (UrQMD) simulation data. [ABSTRACT FROM AUTHOR]

Background: Colorectal cancer (CRC) is prevalent worldwide and is often challenged by treatment failure and recurrence due to resistance to radiotherapy. Here, we aimed to identify the elusive underlying molecular mechanisms of radioresistance in CRC.Methods: Weighted gene co-expression network analysis was used to identify potential radiation-related genes. Colony formation and comet assays and multi-target single-hit survival and xenograft animal models were used to validate the results obtained from the bioinformatic analysis. Immunohistochemistry was performed to examine the clinical characteristics of ALDH1L2. Co-immunoprecipitation, immunofluorescence and flow cytometry were used to understand the molecular mechanisms underlying radioresistance.Results: Bioinformatic analysis, in vitro, and in vivo experiments revealed that ALDH1L2 is a radiation-related gene, and a decrease in its expression induces radioresistance in CRC cells by inhibiting ROS-mediated apoptosis. Patients with low ALDH1L2 expression exhibit resistance to radiotherapy. Mechanistically, ALDH1L2 interacts with thioredoxin (TXN) and regulates the downstream NF-κB signaling pathway. PX-12, the TXN inhibitor, overcomes radioresistance due to decreased ALDH1L2.Conclusions: Our results provide valuable insights into the potential role of ALDH1L2 in CRC radiotherapy. We propose that the simultaneous application of TXN inhibitors and radiotherapy would significantly ameliorate the clinical outcomes of patients with CRC having low ALDH1L2. [ABSTRACT FROM AUTHOR]

The surface of CdTe quantum dots (Q-dots) was modified with thioglycolic acid (TGA) and these Q-dots were then covalently conjugated to amino-functionalized silica-coated carbon dots (C-dot@SiO) via carbodiimide chemistry. The Q-dots form kind of 'satellites' on the surface of the C-dot@SiO nanoparticles. The nanoparticle conjugates display dual emission (with peaks at 441 nm and 605 nm) under UV excitation and were further characterized by transmission electron microscopy, UV-vis absorption and FTIR spectroscopy. The C-dot@SiO@Q-dots hybrid spheres are shown to represent a ratiometric fluorescent probe for Cu in that the emission of the Q-dots is quenched by Cu, while the emission of the C-dots (which are coated with SiO) is not quenched. The ratio of the fluorescence intensities at 441 and 655 nm is related to the concentration of Cu in the range from 0.1 to 1.0 μM, with a 0.096 μM lower detection limit. The ratiometric probe was successfully applied to the determination of Cu in (spiked) vegetable and fruit samples by the standard addition method, and recoveries ranged from 96.7 to 100.8 %. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]