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In this paper we present a generalized Deep Learning-based approach for solving ill-posed large-scale inverse problems occuring in medical image reconstruction. Recently, Deep Learning methods using iterative neural networks and cascaded neural networks have been reported to achieve state-of-the-art results with respect to various quantitative quality measures as PSNR, NRMSE and SSIM across different imaging modalities. However, the fact that these approaches employ the forward and adjoint operators repeatedly in the network architecture requires the network to process the whole images or volumes at once, which for some applications is computationally infeasible. In this work, we follow a different reconstruction strategy by decoupling the regularization of the solution from ensuring consistency with the measured data. The regularization is given in the form of an image prior obtained by the output of a previously trained neural network which is used in a Tikhonov regularization framework. By doing so, more complex and sophisticated network architectures can be used for the removal of the artefacts or noise than it is usually the case in iterative networks. Due to the large scale of the considered problems and the resulting computational complexity of the employed networks, the priors are obtained by processing the images or volumes as patches or slices. We evaluated the method for the cases of 3D cone-beam low dose CT and undersampled 2D radial cine MRI and compared it to a total variation-minimization-based reconstruction algorithm as well as to a method with regularization based on learned overcomplete dictionaries. The proposed method outperformed all the reported methods with respect to all chosen quantitative measures and further accelerates the regularization step in the reconstruction by several orders of magnitude.We synthesized the alkaline-earth metal-doped FeSe compounds (NH3) y AE x FeSe (AE Ca, Sr and Ba), using the liquid NH3 technique, to determine their superconducting properties and crystal structures. Multiple superconducting phases were obtained in each sample of (NH3) y Ca x FeSe and (NH3) y Ba x FeSe, which showed two superconducting transition temperatures (T c's) as high as 37-39 K and 47-48 K at ambient pressure, hereinafter referred to as the 'low-T c phase' and 'high-T c phase', respectively. The high-T c phases in (NH3) y Ca x FeSe and (NH3) y Ba x FeSe were metastable, and rapidly converted to their low-T c phases. However, T c values of 38.4 K and 35.6 K were recorded for (NH3) y Sr x FeSe, which displayed different behavior than (NH3) y Ca x FeSe and (NH3) y Ba x FeSe. The Le Bail fitting of x-ray diffraction (XRD) patterns provided lattice constants of c = 16.899(1) Å and c = 16.8630(8) Å for the low-T c phases of (NH3) y Ca x FeSe and (NH3) y Ba x FeSe, respectively. The lattice constants of their high-T c phases could not be determined due to the disappearance of the high T c phase within a few days. The XRD pattern for (NH3) y Sr x FeSe indicated the coexistence of two phases with c = 16.899(3) Å and c = 15.895(4) Å. The former value of c in (NH3) y Sr x FeSe is almost the same as those of the low-T c phases in (NH3) y Ca x FeSe and (NH3) y Ba x FeSe. Therefore, the phase with c = 16.899(3) Å in (NH3) y Sr x FeSe must correspond to the superconducting phase with the T c of 38.4 K, while the superconducting phase with T c = 35.6 K is assigned to the crystal phase with c = 15.895(4) Å. For (NH3) y Sr x FeSe, a high-T c phase with T c = 47-48 K has not yet been obtained, but a new phase showing the T c value of 35.6 K was clearly obtained. This is the first systematic study of the preparation, crystal structure, and superconductivity of alkaline-earth metal-doped FeSe, (NH3) y AE x FeSe.Objective Developing a new neuromodulation method for epilepsy treatment requires a large amount of time and resources to find effective stimulation parameters and often fails due to inter-subject variability in stimulation effect. As an alternative, we present a novel data-driven surrogate approach which can optimize the neuromodulation efficiently by investigating the stimulation effect on surrogate neural states. Approach Medial septum (MS) optogenetic stimulation was applied for modulating electrophysiological activities of the hippocampus in a rat temporal lobe epilepsy model. For the new approach, we implemented machine learning techniques to describe the pathological neural states and to optimize the stimulation parameters. Specifically, first, we found neural state surrogates to estimate a seizure susceptibility based on hippocampal local field potentials. Second, we modulated the neural state surrogates in a desired way with the subject-specific optimal stimulation parameters found by in vivo Bayesiaand further improve therapeutic effectiveness. This approach also can be used for improving neuromodulation treatment of other neurological or psychiatric diseases.Acute kidney injury (AKI) is a common renal dysfunction. Renal ischemia-reperfusion (I/R) injury contributes to AKI progression. The microRNA miR-195-5p can act as a crucial tumor inhibitor in various cancers. However, the potential biological effects of miR-195-5p on AKI are not well-understood. We found that miR-195-5p levels were decreased in the serum samples of patients with AKI. Next, we determined miR-195-5p expression in the renal tissues of the rats and found that it was downregulated. Renal function was evaluated and confirmed using blood urea nitrogen and serum Cr levels. In parallel, the hypoxia-induced NRK-52E cell model was employed, and miR-195-5p was found to be markedly reduced under hypoxic conditions. Furthermore, miR-195-5p was modulated in NRK-52E cells. miR-195-5p induced NRK-52E cell proliferation and protected NRK-52E cells against hypoxia-triggered apoptosis. In an I/R mouse model, miR-195-5p alleviated renal injury triggered by I/R. In addition, oxidative stress and inflammatory factor concentrations were assessed using ELISA. The results showed that miR-195-5p mimicked attenuated oxidative stress induced by I/R injury and downregulated the protein expression of inflammatory factors. Moreover, we identified that vascular endothelial growth factor A (VEGFA) was a target gene of miR-195-5p, which could negatively regulate VEGFA expression in vitro. Inhibitors of miR-195-5p subsequently contributed to renal injury, which was reversed by VEGFA loss. find more In conclusion, miR-195-5p may repress AKI by targeting VEGFA.Background TP53 plays critical roles in sensitivity to chemotherapy, and aging. Collagen is very important in aging. The molecular structure and biochemical properties of collagen changes during aging. The discoidin domain receptor (DDR1) is regulated in part by collagen. Elucidating the links between TP53 and DDR1 in chemosensitivity and aging could improve therapies against cancer and aging. Results Restoration of WT-TP53 activity resulted in increased sensitivity to chemotherapeutic drugs and elevated expression of key components of the Raf/MEK/ERK, PI3K/Akt and DDR1 pathways. DDR1 could modulate the levels of Raf/MEK/ERK and PI3K/Akt pathways as well as sensitize the cells to chemotherapeutic drugs. In contrast, suppression of WT TP53 with a dominant negative (DN) TP53 gene, suppressed DDR1 protein levels and increased their chemoresistance. Conclusion Restoration of WT TP53 activity or increased expression of the anti-aging DDR1 collagen receptor can result in enhanced sensitivity to chemotherapeutic drugs. Our innovative studies indicate the important links between WT TP53 and DDR1 which can modulate Raf/MEK/ERK and PI3K/Akt signaling as well as chemosensitivity and aging. Methods We investigated the roles of wild type (WT) and mutant TP53 on drug sensitivity of prostate cancer cells and the induction of Raf/MEK/ERK, PI3K/Akt and DDR1 expression and chemosensitivity.Background Regular physical activity and doing well in school are important for growing adolescents. In this study, the associations between physical activity and perceived school performance (PSP) are examined together. Methods Young adolescents from 42 countries (n = 193,949) in Europe and Canada were examined for associations between self-reported moderate to vigorous physical activity (MVPA) and PSP. Multinominal analyses were conducted with 0 to 2 days of MVPA and below average PSP as reference categories. Adjusted odds ratios and 95% confidence intervals were reported for pooled data and individual countries after controlling for family affluence scale. Results Girls had better PSP than boys, yet more boys participated in daily MVPA than girls. The associations between PSP and MVPA were inverted U shaped. The strongest association for very good PSP was among young adolescents who reported 5 to 6 days MVPA (odds ratios = 2.3; 95% confidence interval, 2.1-2.4) after controlling for family affluence scale. Conclusions Young adolescents with average or better PSP took part in at least 3 days of MVPA in a week, suggesting that participating in some MVPA was positively associated with PSP. More days of MVPA in a week, especially for young adolescents with below average PSP, would be beneficial for health and school performance.Slip outcomes are categorized as either a backward loss of balance (LOB) or a no loss of balance (no-LOB) in which an individual does not take a backward step to regain their stability. LOB includes falls and nonfalls, while no-LOB includes skate overs and walkovers. Researchers are uncertain about which factors determine slip outcomes and at which critical instants they do so. The purpose of the study was to investigate factors affecting slip outcomes in proactive and early reactive phases by analyzing 136 slip trials from 68 participants (age 72.2 [5.3] y, female 22). Segment angles and average joint moments in the sagittal plane of the slipping limb were compared for different slip outcomes. The results showed that knee flexor, hip extensor, and plantar flexor moments were significantly larger for no-LOB than for LOB in the midproactive phase, leading to smaller shank-ground and foot-ground angles at the slip onset, based on forward dynamics. In the early reactive phase, the hip extensor and plantar flexor moments were larger for no-LOB than for LOB, and all segment angles were smaller for no-LOB. Our findings indicate that the shank angle and knee moment were the major determinants of slip outcomes in both proactive and reactive phases.Background With the pervasiveness of social media, online health communities (OHC) are an important tool for facilitating information sharing and support among people with chronic health conditions. Importantly, OHCs offer insight into conversations about the lived experiences of people with particular health conditions. What is less known is what aspects of OHCs are important to maintain safe and productive conversations that support health. Objective This research aims to assess the provision of social support and the role of active moderation in OHCs developed in accordance with and managed by an adaptive engagement model. This study aims to identify key elements of the model that are central to the development, maintenance, and adaptation of OHCs for people with chronic health conditions. Methods This research uses Combined Content Analysis, a mixed-methods approach, to analyze sampled Facebook post comments from 6 OHCs to understand how key aspects of the adaptive engagement model facilitate different types of social support.

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