4,992 research outputs found

    Arch double phase conjugation in photorefractive BaTiO3 crystal

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    Phase-Tunable Calcium Phosphate Biomaterials Synthesis and Application in Protein Delivery

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    Calcium phosphates (CaP) are important biomaterials used in tissue engineering and drug delivery, due to their biocompatibility, low toxicity, and osteoconductivity. However, controlling the phase of CaP, especially tricalcium phosphate (TCP), is very challenging under mild conditions, particularly when using one preparation protocol for all CaP phases. It is also crucial to produce these biomaterials economically and reproducibly. Herein, three of the most commonly employed CaP, including beta-tricalcium phosphate (β-TCP), dicalcium phosphate anhydrous (DCPA), and hydroxyapatite (HA) were, for the first time, successfully synthesized by altering the reaction solvent, using calcium acetate monohydrate as a precursor and a rapid microwave-assisted synthetic method. A variety of CaP particle morphologies were obtained, including elliptical and plate-shaped with different porosities. Compared with conventional heating, CaP biomaterials synthesized using microwave heating showed greater reproducibility, higher yields, and shorter reaction time. By varying the reaction solvents, morphologies and phases of CaP were controlled, leading to an enhanced protein bovine serum albumin (BSA) loading, with a higher BSA absorption observed according to the trend DCPA> β-TCP > HA. Furthermore, the phase, specific surface area, and pore size were shown to play decisive roles in protein desorption with a higher release amount observed according to the trend DCPA > β-TCP > HA. Finally, it is found that larger pores are also beneficial to BSA adsorption

    A Unique Relationship Determining Strength of Silty/Clayey Soils - Portland Cement Mixes

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    This technical note advances the understanding of the key parameters controlling unconfined compressive strength (qu) of artificially cemented silty/clayey soils by considering distinct moisture contents, distinct specimen porosities (η), different Portland cement contents and any curing time periods. The qu values of the specimens moulded for each curing period were normalized (i.e. divided) by the qu attained by a specimen with a specific porosity/cement ratio. A unique relationship was found, establishing the relationship between strength for artificially cemented silty/clayey soils considering all porosities, Portland cement amounts, moisture contents and curing periods studied. From a practical viewpoint, this means that, at limit, carrying out only one unconfined compression test with a silty/clayey soil specimen, moulded with a specific Portland cement amount, a specific porosity and moisture content and cured for a given time period, allows the determination of a general relationship equation that controls the strength for an entire range of porosities and cement contents, reducing considerably the amount of moulded specimens and reducing projects development cost and time

    Specific subsystems of the inferior parietal lobule are associated with hand dysfunction following stroke: A cross-sectional resting-state fMRI study

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    Aim The inferior parietal lobule (IPL) plays important roles in reaching and grasping during hand movements, but how reorganizations of IPL subsystems underlie the paretic hand remains unclear. We aimed to explore whether specific IPL subsystems were disrupted and associated with hand performance after chronic stroke. Methods In this cross-sectional study, we recruited 65 patients who had chronic subcortical strokes and 40 healthy controls from China. Each participant underwent the Fugl-Meyer Assessment of Hand and Wrist and resting-state fMRI at baseline. We mainly explored the group differences in resting-state effective connectivity (EC) patterns for six IPL subregions in each hemisphere, and we correlated these EC patterns with paretic hand performance across the whole stroke group and stroke subgroups. Moreover, we used receiver operating characteristic curve analysis to distinguish the stroke subgroups with partially (PPH) and completely (CPH) paretic hands. Results Stroke patients exhibited abnormal EC patterns with ipsilesional PFt and bilateral PGa, and five sensorimotor-parietal/two parietal–temporal subsystems were positively or negatively correlated with hand performance. Compared with CPH patients, PPH patients exhibited abnormal EC patterns with the contralesional PFop. The PPH patients had one motor-parietal subsystem, while the CPH patients had one sensorimotor-parietal and three parietal-occipital subsystems that were associated with hand performance. Notably, the EC strength from the contralesional PFop to the ipsilesional superior frontal gyrus could distinguish patients with PPH from patients with CPH. Conclusions The IPL subsystems manifest specific functional reorganization and are associated with hand dysfunction following chronic stroke.Natural Science Foundation of Zhejiang Province, Grant/Award Number: LGF19H270001; Shanghai Sailing Program, Grant/Award Number: 20YF144510

    Evaluating rapid evolutionary radiation in Goniothalamus (Annonaceae)

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    Oral Presentation - Session 1: Taxonoly & Biosystematic-1Main Theme: Contributions of Flora Malesiana to the Welfare of People in AsiaBoth intrinsic and environmental factors may result in changes in diversification rate in a lineage. Significant shifts in evolutionary tempo, including rapid evolutionary radiation, are of particular interest as they are key to understanding how factors such as the timing of diversifications, species attributes, environmental conditions and the size and complexity of geographical regions have shaped current patterns of biodiversity. The Annonaceae is a species-rich fami...postprin

    Learning Optimal Deep Projection of 18^{18}F-FDG PET Imaging for Early Differential Diagnosis of Parkinsonian Syndromes

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    Several diseases of parkinsonian syndromes present similar symptoms at early stage and no objective widely used diagnostic methods have been approved until now. Positron emission tomography (PET) with 18^{18}F-FDG was shown to be able to assess early neuronal dysfunction of synucleinopathies and tauopathies. Tensor factorization (TF) based approaches have been applied to identify characteristic metabolic patterns for differential diagnosis. However, these conventional dimension-reduction strategies assume linear or multi-linear relationships inside data, and are therefore insufficient to distinguish nonlinear metabolic differences between various parkinsonian syndromes. In this paper, we propose a Deep Projection Neural Network (DPNN) to identify characteristic metabolic pattern for early differential diagnosis of parkinsonian syndromes. We draw our inspiration from the existing TF methods. The network consists of a (i) compression part: which uses a deep network to learn optimal 2D projections of 3D scans, and a (ii) classification part: which maps the 2D projections to labels. The compression part can be pre-trained using surplus unlabelled datasets. Also, as the classification part operates on these 2D projections, it can be trained end-to-end effectively with limited labelled data, in contrast to 3D approaches. We show that DPNN is more effective in comparison to existing state-of-the-art and plausible baselines.Comment: 8 pages, 3 figures, conference, MICCAI DLMIA, 201
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