Cappsaguirre8888

The aim of this paper is to investigate the feasibility and limitations of activity-concentration estimation for223Ra using SPECT. Phantom measurements are performed using spheres (volumes 5.5 mL to 26.4 mL, concentrations 1.6 kBq mL-1to 4.5 kBq mL-1). Furthermore, SPECT projections are simulated using the SIMIND Monte Carlo program for two geometries, one similar to the physical phantom and the other being an anthropomorphic phantom with added lesions (volumes 34 mL to 100 mL, concentrations 0.5 kBq mL-1to 4 kBq mL-1). Medium-energy and high-energy collimators, 60 projections with 55 s per projection and a 20 % energy window at 82 keV are employed. For the Monte Carlo simulated images, Poisson-distributed noise is added in ten noise realizations. Reconstruction is performed (OS-EM, 40 iterations, 6 subsets) employing compensation for attenuation, scatter, and collimator-detector response. The estimated concentrations in the anthropomorphic phantom are also corrected using recovery coefficients. Errors for the largest sphere in the physical phantom range from -25 % to -34 % for the medium-energy collimator and larger deviations for smaller spheres. Corresponding results for the high-energy collimator are -15 % to -31 %. The corresponding Monte Carlo simulations show standard deviations of a few percentage points. For the anthropomorphic phantom, before application of recovery coefficients the bias ranges from -16 % to -46 % (medium-energy collimator) and -10 % to -28 % (high-energy collimator), with standard deviations of 2 % to 14 % and 1 % to 16 %. After the application of recovery coefficients, the biases range from -3 % to -35 % (medium energy collimator) and from 0 % to -18 %. The errors decrease with increasing concentrations. Activity-concentration estimation of223Ra with SPECT is feasible, but problems with repeatability need to be further studied. Creative Commons Attribution license.The physical range uncertainty limits the exploitation of the full potential of charged particle therapy. In this work we face this issue aiming to measure the absolute Bragg peak position in the target. We investigate p,4He,12C and16O beams accelerated at the Heidelberg Ion-Beam Therapy Center. The residual range of the primary12C ions is measured using the prompt gamma spectroscopy method, which was demonstrated for proton beams accelerated by cyclotrons and is developed here for the first time for heavier ions accelerated by a synchrotron. We develop a detector system that includes (i) a spectroscopic unit based on cerium(III) bromide and bismuth germanium oxide scintillating crystals, (ii) a beam trigger based on an array of scintillating fibers and (iii) a data acquisition system based on a FlashADC. We test the system in two different scenarios. In the first series of experiments we detect and identify 19 independent spectral lines over a wide gamma energy spectrum in presence of the four ion species for different targets, including also a water target with a titanium insert. In the second series of experiments we introduce a collimator aiming to relate the spectral information to the range of the primary particles. We perform extensive measurements for a12C beam and demonstrate submillimetric precision for the measurement of its Bragg peak position in the experimental setup. The features of the energy and time spectra for gamma radiation induced by p,4He and16O are investigated upstream and downstream the Bragg peak position. We conclude the analysis extrapolating the required future developments, which would be needed to achieve range verification with a 2 mm accuracy during a single fraction delivery of D = 2 Gy physical dose. © 2020 Institute of Physics and Engineering in Medicine.Despite intracellular molecular dynamics being fundamental to understand pathological, biomechanical or biochemical events, several processes are still not clear because of the difficulty of monitoring and measuring these phenomena. To engineer an effective fluorescent tool useful to improve protein intracellular tracking studies, we fused a supernegative green fluorescent protein, (-30)GFP, to a myogenic transcription factor, MyoD. The (-30)GFP-MyoD was able to pass the plasma membrane when complexed with cationic lipids. Fluorescence confocal microscopy showed the protein delivery in just 3 hours with high levels of protein transduction efficiency. Confocal acquisitions also confirmed the maintenance of the MyoD nuclear localization. To examine how the supernegative GFP influenced MyoD activity, we did gene expression analyses, which showed an inhibitory effect of (-30)GFP on transcription factor function. This negative effect was possibly due to a charge-driven interference mechanism, as suggested by further investigations by molecular dynamics simulations. Summarizing these results, despite the functional limitations related to the charge structural characteristics that specifically affected MyoD function, we found (-30)GFP is a suitable fluorescent label for improving protein intracellular tracking studies, such as nucleocytoplasmic transport in mechanotransduction.Understanding the processes underlying sensorimotor coupling with the environment is crucial for sensorimotor rehabilitation and sensory substitution. In doing so, devices which provide novel sensory feedback consequent to body movement may be optimized in order to enhance motor performance for particular tasks. The aim of the study reported here was to investigate audio-motor coupling when the auditory experience is linked to movements of the head or the hands. The participants had to localize and reach a virtual source with the dominant hand in response to sounds. An electromagnetic system recorded the position and orientation of the participants' head and hands. This system was connected to a 3D audio system that provided binaural auditory feedback on the position of the virtual listener located on the participants' body. The listener's position was computed either from the hands or from the head. For the hand condition, the virtual listener was placed on the dominant hand (the one used to reach the target) in Experiment 1 and on the non-dominant hand, which was constrained in order to have similar amplitude and degrees of freedom as that of the head, in Experiment 2. The results revealed that, in the two experiments, the participants were able to localize a source within the 3D auditory environment. Performance varied as a function of the effector's degrees of freedom and the spatial coincidence between sensor and effector. The results also allowed characterizing the kinematics of the hand and head and how they change with audio-motor coupling condition and practice.Instead of understanding symptoms in a way where a latent cause exists and symptoms serve as its indicators, the network approach enables an innovative comprehension on psychological disorders that focuses on causal interactions. There is need to update the knowledge in this direction in Chinese context. This study strives to apply network approach to deepening the understanding of complicated grief (CG) among older adults in rural China. A sample of older participants (N = 352) who experienced spousal bereavement living in Zhejiang Province of China were administrated with face-to-face interviews. Networks analysis was conducted to realize the object of this study. The 19-item ICG network revealed that symptoms were both positively and negatively connected within the network. The most three central symptoms were "feeling longing for the person who died" and "memories of the dead", and feeling lonely". Edge-weights accuracy and centrality stability were tested in order to remind carefulness when interpreting the results. This study demonstrates the utility of a network approach in deepening the understanding of the structure of CG symptoms among Chinese older people. Strengths and limitations, as well as implications for informing the assessment and treatment of this disorder, were discussed. BACKGROUND Non-motor symptoms (NMS) are common in Parkinson's disease (PD), but their relationships to nigrostriatal degeneration remain largely unexplored. METHODS We evaluated 18 NMS scores covering 5 major domains in relation to concurrent and future dopamine transporter (DAT) imaging in 344 PD patients from the Parkinson's Progression and Markers Initiative (PPMI). We standardized NMS assessments into z-scores for side-by-side comparisons. Patients underwent sequential DaTSCAN imaging at enrollment and at months 12, 24, and 48. Specific binding ratios (SBR) were calculated using the occipital lobe reference region. We evaluated the association of striatal DAT binding at the four time points with each baseline NMS using mixed-effects regression models. RESULTS Multiple baseline NMS were significantly associated with DAT binding at baseline and at follow-up scans. WAY-316606 molecular weight REM sleep behavior disorder (RBD) symptoms showed the strongest association - mean striatal SBR declined with increasing RBD symptom z-score (average of time-point-specific slopes per unit change in z-score βAVG = -0.083, SE = 0.017; p  less then  0.0001). In addition, striatal DAT binding was linearly associated with increasing baseline z-scores positively for the memory (βAVG=0.055, SE = 0.022; p = 0.01) and visuospatial (βAVG=0.044, SE = 0.020; p = 0.03) cognitive domains, and negatively for total anxiety (βAVG= -0.059, SE = 0.018; p = 0.001). Striatal DAT binding showed curvilinear associations with odor identification, verbal discrimination recognition, and autonomic dysfunction z-scores (p = 0.001, p = 0.0009, and p = 0.0002, respectively). Other NMS were not associated with DAT binding. CONCLUSIONS Multiple NMS, RBD symptoms in particular, are associated with nigrostriatal dopaminergic changes in early PD. Small-angle X-ray scattering (SAXS) method is widely used in investigating protein structures in solution, but high-quality 3D model reconstructions are challenging. We present a new algorithm based on a deep learning method for model reconstruction from SAXS data. An auto-encoder for protein 3D models was trained to compress 3D shape information into vectors of a 200-dimensional latent space, and the vectors are optimized using genetic algorithms to build 3D models that are consistent with the scattering data. The program has been tested with experimental SAXS data, demonstrating the capacity and robustness of accurate model reconstruction. Furthermore, the model size information can be optimized using this algorithm, enhancing the automation in model reconstruction directly from SAXS data. The program was implemented using Python with the TensorFlow framework, with source code and webserver available from http//liulab.csrc.ac.cn/decodeSAXS. Mammalian brain development critically depends on proper thyroid hormone signaling, via the TRα1 nuclear receptor. The downstream mechanisms by which TRα1 impacts brain development are currently unknown. In order to investigate these mechanisms, we used mouse genetics to induce the expression of a dominant-negative mutation of TRα1 specifically in GABAergic neurons, the main inhibitory neurons in the brain. This triggered post-natal epileptic seizures and a profound impairment of GABAergic neuron maturation in several brain regions. Analysis of the transcriptome and TRα1 cistrome in the striatum allowed us to identify a small set of genes, the transcription of which is upregulated by TRα1 in GABAergic neurons and which probably plays an important role during post-natal maturation of the brain. Thus, our results point to GABAergic neurons as direct targets of thyroid hormone during brain development and suggest that many defects seen in hypothyroid brains may be secondary to GABAergic neuron malfunction.