Magnetic resonance imaging analysis of moving fronts in floating dosage forms

An application of magnetic resonance imaging in the field of pharmaceutical technology is presented in this paper. The analysis of diffusion and swelling fronts was carried out for four floating dosage forms using magnetic resonance imaging. The influence of polymer viscosity, its concentration, and type of applied dissolution media on the area of moving fronts was investigated

Angular distributions in Monte Carlo event generation of weak single-pion production

One of the substantial sources of systematic errors in neutrino oscillation experiments that utilize neutrinos from accelerator sources stems from a lack of precision in modeling single-pion production (SPP). Oscillation analyses rely on Monte Carlo event generators (MC), providing theoretical predictions of neutrino interactions on nuclear targets. Pions produced in these processes provide a significant fraction of oscillation signal and background on both elementary scattering and detector simulation levels. Thus, it is of critical importance to develop techniques that will allow us to accommodate state-of-the-art theoretical models describing SPP into MCs. In this work, we investigate various algorithms to implement single-pion production models in Monte Carlo event generators. Based on comparison studies, we propose a novel implementation strategy that combines satisfactory efficiency with high precision in reproducing details of theoretical models predictions, including pion angular distributions. The proposed implementation is model-independent, thereby providing a framework that can include any model for SPP. We have tested the new algorithm with the Ghent Low Energy Model for single-pion production implemented in the NuWro Monte Carlo event generator.Comment: 13 pages, 8 figure

Implementation of the CRPA model in the GENIE event generator and analysis of nuclear effects in low-energy transfer neutrino-nucleus interactions

We present the implementation and validation of the Hartree-Fock continuum random phase approximation (HF-CRPA) model in the GENIE neutrino-nucleus interaction event generator and a comparison of the subsequent predictions to experimental measurements of lepton kinematics from interactions with no mesons in the final state. These predictions are also compared to those of other models available in GENIE. It is shown that, with respect to these models, HF-CRPA predicts a significantly different evolution of the cross section when moving between different interaction targets, when considering incoming anti-neutrinos compared to neutrinos and when changing neutrino energies. These differences are most apparent for interactions with low energy and momentum transfer. It is also clear that the impact of nucleon correlations within the HF-CRPA framework is very different than in GENIE's standard implementation of RPA corrections. Since many neutrino oscillation experiments rely on their input model to extrapolate between targets, flavours, and neutrino energies, the newly implemented HF-CRPA model provides a useful means to verify that such differences between models are appropriately covered in oscillation analysis systematic error budgets.Comment: 13 pages, 12 figures. Significant update from previous versio

Deletion of LBR N-terminal domains recapitulates Pelger-Huet anomaly phenotypes in mouse without disrupting X chromosome inactivation

Mutations in the gene encoding Lamin B receptor (LBR), a nuclear-membrane protein with sterol reductase activity, have been linked to rare human disorders. Phenotypes range from a benign blood disorder, such as Pelger-Huet anomaly (PHA), affecting the morphology and chromatin organization of white blood cells, to embryonic lethality as for Greenberg dysplasia (GRBGD). Existing PHA mouse models do not fully recapitulate the human phenotypes, hindering efforts to understand the molecular etiology of this disorder. Here we show, using CRISPR/Cas-9 gene editing technology, that a 236bp N-terminal deletion in the mouse Lbr gene, generating a protein missing the N-terminal domains of LBR, presents a superior model of human PHA. Further, we address recent reports of a link between Lbr and defects in X chromosome inactivation (XCI) and show that our mouse mutant displays minor X chromosome inactivation defects that do not lead to any overt phenotypes in vivo. We suggest that our N-terminal deletion model provides a valuable pre-clinical tool to the research community and will aid in further understanding the etiology of PHA and the diverse functions of LBR

Towards a more complete description of nucleon distortion in lepton-induced single-pion production at low-Q2Q^2

Theoretical predictions for lepton-induced single-pion production (SPP) on $^{12}$C are revisited in order to assess the effect of different treatments of the current operator. On one hand we have the asymptotic approximation, which consists in replacing the particle four-vectors that enter in the operator by their asymptotic values, i.e., their values out of the nucleus. On the other hand we have the full calculation, which is a more accurate approach to the problem. We also compare with results in which the final nucleon is described by a relativistic plane wave, to rate the effect of the nucleon distortion. The study is performed for several lepton kinematics, reproducing inclusive and semi-inclusive cross sections belonging to the low-$Q^2$ region (between 0.05 and 1 GeV$^2$), which is of special interest in charged-current (CC) neutrino-nucleus 1$\pi$ production. Inclusive electron results are compared with experimental data. We find non-trivial corrections comparable in size with the effect of the nucleon distortion, namely, corrections up to 6\%, either increasing or diminishing the asymptotic prediction, and a shift of the distributions towards higher energy transfer. For the semi-inclusive cross sections, we observe the correction to be prominent mainly at low values of the outgoing nucleon kinetic energy. Finally, for CC neutrino-induced 1$\pi^+$ production, we find a reduction at low-$Q^2$ with respect to both the plane-wave approach and the asymptotic case

Effect of Surface Treatments on the Nanomechanical Properties of Human Hair.

The structural properties of hair are largely determined by the state of the surface. Advanced imaging modes of atomic force microscopy, where the surface mechanics can be correlated with surface topography, have been used to spatially map variations in hair surfaces following chemical and mechanical treatments. Through analysis of multilayered data obtained in this way, we show that the processes of bleaching and combing of hair not only alter the surface roughness, but also alter the mechanical stiffness, adhesion properties, and surface potential of hair, in terms of the mean values and their distributions. These treatments are shown to have a significant effect on the nanoscale surface properties, consistent with what has previously been observed at the macroscopic fiber-level scale.Unileve

A single-cell method to map higher-order 3D genome organization in thousands of individual cells reveals structural heterogeneity in mouse ES cells

In eukaryotes, the nucleus is organized into a three dimensional structure consisting of both local interactions such as those between enhancers and promoters, and long-range higher-order structures such as nuclear bodies. This organization is central to many aspects of nuclear function, including DNA replication, transcription, and cell cycle progression. Nuclear structure intrinsically occurs within single cells; however, measuring such a broad spectrum of 3D DNA interactions on a genome-wide scale and at the single cell level has been a great challenge. To address this, we developed single-cell split-pool recognition of interactions by tag extension (scSPRITE), a new method that enables measurements of genome-wide maps of 3D DNA structure in thousands of individual nuclei. scSPRITE maximizes the number of DNA contacts detected per cell enabling high-resolution genome structure maps within each cells and is easy-to-use and cost-effective. scSPRITE accurately detects chromosome territories, active and inactive compartments, topologically associating domains (TADs), and higher-order structures within single cells. In addition, scSPRITE measures cell-to-cell heterogeneity in genome structure at different levels of resolution and shows that TADs are dynamic units of genome organization that can vary between different cells within a population. scSPRITE will improve our understanding of nuclear architecture and its relationship to nuclear function within an individual nucleus from complex cell types and tissues containing a diverse population of cells

What about a beta-beam facility for low energy neutrinos?

A novel method to produce neutrino beams has recently been proposed : the beta-beams. This method consists in using the beta-decay of boosted radioactive nuclei to obtain an intense, collimated and pure neutrino beam. Here we propose to exploit the beta-beam concept to produce neutrino beams of low energy. We discuss the applications of such a facility as well as its importance for different domains of physics. We focus, in particular, on neutrino-nucleus interaction studies of interest for various open issues in astrophysics, nuclear and particle physics. We suggest possible sites for a low energy beta-beam facility.Comment: 4 pages, 1 figur