Using two-nucleon and three-nucleon interactions derived in the framework of chiral perturbation theory (ChPT) with and without the explicit Δ isobar contributions, we calculate the energy per ...particle of symmetric nuclear matter and pure neutron matter employing the microscopic Brueckner-Hartree-Fock approach. Specifically, we present nuclear matter calculations using the new fully local in coordinate-space two-nucleon interaction at the next-to-next-to-next-to-leading-order (N3LO) of ChPT with Δ isobar intermediate states (N3LOΔ) recently developed by Piarulli et al. 1 supplemented with a local N2LO three-nucleon interaction with explicit Δ isobar degrees of freedom. We show that for this combination of two- and three-nucleon interactions it is possible to obtain a good saturation point of symmetric nuclear matter. We also calculate the nuclear symmetry energy and compare our results with the available empirical constraints on this quantity.
We describe a method to study diffusion of rhodamine 6G dye in single silica nanochannels using arrays of silica nanochannels. Dynamics of the molecules inside single nanochannel is found from the ...change of the dye concentration in solution with time. A 10(8) decrease in the dye diffusion coefficient relative to water was observed. In comparison to single fluorescent molecule studies, the presented method does not require fluorescence of the diffusing molecules.
Growth of even simple crystals is a rather hard problem to describe because of the non-equilibrium nature of the process. Meso(nano)porous silica particles, which are self-assembled in a sol-gel ...template synthesis, demonstrate an example of shapes of high complexity, similar to those observed in the biological world. Despite such complexity, here we present the evidence that at least a part of the formation of these shapes is an equilibrium process. We demonstrate it for an example of mesoporous fibers, one of the abundant shapes. We present a quantitative proof that the fiber free energy is described by the Boltzmann distribution, which is predicted by the equilibrium thermodynamics. This finding may open up new ground for a quantitative description of the morphogenesis of complex self-assembled shapes, including biological hierarchy.
This is a collection of perspective pieces contributed by the participants of the Institute for Nuclear Theory’s Program on
Nuclear Physics for Precision Nuclear Physics
which was held virtually from ...April 19 to May 7, 2021. The collection represents the reflections of a vibrant and engaged community of researchers on the status of theoretical research in low-energy nuclear physics, the challenges ahead, and new ideas and strategies to make progress in nuclear structure and reaction physics, effective field theory, lattice QCD, quantum information, and quantum computing. The contributed pieces solely reflect the perspectives of the respective authors and do not represent the viewpoints of the Institute for Nuclear theory or the organizers of the program.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
To date, the methods for detection of cancer cells are mostly based on traditional techniques used in biology, such as visual identification of malignant changes, cell‐growth analysis, specific ...ligand–receptor labeling, or genetic tests. Despite being well developed, these methods are either insufficiently accurate or require a lengthy complicated analysis. A search for alternative methods for the detection of cancer cells may be a fruitful approach. Proposed here is a novel method for the detection of cancer cells in vitro, which is based on nonspecific adhesion of silica beads to cells. First, atomic force microscopy is used to study the adhesion of single silica beads to malignant and normal cells cultured from human cervix. It is found that adhesion depends on the time of contact, and can be statistically different for malignant and normal cells. Using these data, an optical method utilizing fluorescent silica beads is developed, which is based on detection of the difference in the number of adherent particles. The method is tested using primary cells cultured from cervical tissues of three healthy individuals and three patients with cervical cancer. The method shows sufficiently high sensitivity for cancer to make it interesting to perform further statistical tests.
The adhesion of silica beads to malignant and normal cells cultured from human cervix is studied by atomic force microscopy (AFM). A simple method for the detection of cancer cells in vitro is developed that uses fluorescent silica beads (see picture). The method is based on the use of nontraditional, just physical (nonspecific) adhesion.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Self-assembly of nanoporous silica shapes is of great interest for modern nanotechnology because of uniform pore size, simplicity, and low cost of production. However, there are two major problems ...that prevent broad use of the self-assembly process. First, the process brings too broad a variety of the assembled shapes. Secondly, the yield of the desired shapes is far from 100%. Here, we describe a process of acidic self-assembly of silica shapes that is free of both of these problems. The process described results in virtually a 100% of very uniform fibers. Each fiber has a hexagonal cross section of approximately 2 /spl mu/m and a length of approximately 5 /spl mu/m. The highly uniform pores with periodicity of 3.8 nm are unidirectional along the fiber. These new fibers can be used in chromatography, drug delivery, manufacturing nanowires, nanoreactors for "one-dimensional" chemistry, etc.
Using the hyperspherical adiabatic method with the realistic nuclear potentials Argonne V14, Argonne V18, and Argonne V18 with the Urbana IX three-body potential, we calculate the adiabatic ...potentials and the triton bound state energies. We find that a discrete variable representation with the slow variable discretization method along the hyperradial degree of freedom results in energies consistent with the literature. However, using a Laguerre basis results in missing energy, even when extrapolated to an infinite number of basis functions and channels. We do not include the isospin
T
= 3/2 contribution in our analysis.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
We investigate the properties of the excited state of $^4\mathrm{He}$,
$^4\mathrm{He}^*$, within the framework of Efimov physics and its connection to
the unitary point of the nuclear interaction. We ...explore two different
approaches to track the trajectory of $^4\mathrm{He}^*$ as it crosses the
$^3\mathrm{H}$+p threshold and potentially becomes a resonant state. The first
approach involves an analytical continuation of the energy with respect to the
Coulomb coupling, while the second approach introduces an artificial four-body
force that it is gradually released. By utilizing Pad\'e approximants and
extrapolation techniques, we estimate the energy and width of the resonance.
Our results suggest a central energy value of $E_R=0.060(3)$ MeV and a width of
$\Gamma/2=0.036(6)$ MeV using the Coulomb analysis, and $E_R=0.068(1)$ MeV and
$\Gamma/2=0.007(5)$ MeV with the four-body force analysis. Interestingly, these
results are consistent with calculations based on {\it ab-initio} nuclear
interactions but differ from the accepted values of the $0^+$ resonance energy
and width. This highlights the challenges in accurately determining the
properties of resonant states in light nuclei and calls for further
investigations and refinements in theoretical approaches.
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