Combining Fully Convolutional and Recurrent Neural Networks for 3D Biomedical Image Segmentation

Abstract Segmentation of 3D images is a fundamental problem in biomedical image analysis. Deep learning (DL) approaches have achieved state-of-the-art segmentation performance. To exploit the 3D contexts using neural networks, known DL segmentation methods, including 3D convolution, 2D convolution on planes orthogonal to 2D image slices, and LSTM in multiple directions, all suffer incompatibility with the highly anisotropic dimensions in common 3D biomedical images. In this paper, we propose a new DL framework for 3D image segmentation, based on a combination of a fully convolutional network (FCN) and a recurrent neural network (RNN), which are responsible for exploiting the intra-slice and inter-slice contexts, respectively. To our best knowledge, this is the first DL framework for 3D image segmentation that explicitly leverages 3D image anisotropism. Evaluating using a dataset from the ISBI Neuronal Structure Segmentation Challenge and in-house image stacks for 3D fungus segmentation, our approach achieves promising results comparing to the known DL-based 3D segmentation approaches

Development of a Non-invasive Deep Brain Stimulator With Precise Positioning and Real-Time Monitoring of Bioimpedance

Methods by which to achieve non-invasive deep brain stimulation via temporally interfering with electric fields have been proposed, but the precision of the positioning of the stimulation and the reliability and stability of the outputs require improvement. In this study, a temporally interfering electrical stimulator was developed based on a neuromodulation technique using the interference modulation waveform produced by several high-frequency electrical stimuli to treat neurodegenerative diseases. The device and auxiliary software constitute a non-invasive neuromodulation system. The technical problems related to the multichannel high-precision output of the device were solved by an analog phase accumulator and a special driving circuit to reduce crosstalk. The function of measuring bioimpedance in real time was integrated into the stimulator to improve effectiveness. Finite element simulation and phantom measurements were performed to find the functional relations among the target coordinates, current ratio, and electrode position in the simplified model. Then, an appropriate approach was proposed to find electrode configurations for desired target locations in a detailed and realistic mouse model. A mouse validation experiment was carried out under the guidance of a simulation, and the reliability and positioning accuracy of temporally interfering electric stimulators were verified. Stimulator improvement and precision positioning solutions promise opportunities for further studies of temporally interfering electrical stimulation

Efficient removal of Cd(II) from aqueous solution by pinecone biochar: Sorption performance and governing mechanisms

Cadmium (Cd) is one of the most harmful and widespread environmental pollutants. Despite decades-long research efforts, the remediation of water contaminated by Cd has remained a significant challenge. A novel carbon material, pinecone biochar, was previously hypothesized to be a promising adsorbent for Cd, while so far, it has received little attention. This study evaluated the sorption capacity of pinecone biochar through isotherm experiments. Based on Langmuir model, the adsorption maximum for Cd(II) was up to 92.7 mg g−1. The mechanism of Cd(II) adsorption on pinecone biochar was also explored through both thermodynamic and kinetics adsorption experiments, as well as both solution and solid-phase microstructure characterization. The solid-solution partitioning behaviour of Cd(II) fitted best with the Tόth model while the adsorption process followed a pseudo-second-order rate, suggesting that the Cd(II) adsorption on the pinecone biochar was mainly a chemisorption process. Microstructure characteristics and mechanism analysis further suggested that coprecipitation and surface complexation were the main mechanisms of Cd adsorption by biochar. Coprecipitation occurred mainly through the forms of Cd(OH)2 and CdCO3. Our results demonstrated that pinecone biochar was an efficient adsorbent which holds a huge potential for Cd(II) removal from aqueous solution

Cathelicidin-BF, a Snake Cathelicidin-Derived Antimicrobial Peptide, Could Be an Excellent Therapeutic Agent for Acne Vulgaris

Cathelicidins are a family of antimicrobial peptides acting as multifunctional effector molecules in innate immunity. Cathelicidin-BF has been purified from the snake venoms of Bungarus fasciatus and it is the first identified cathelicidin antimicrobial peptide in reptiles. In this study, cathelicidin-BF was found exerting strong antibacterial activities against Propionibacterium acnes. Its minimal inhibitory concentration against two strains of P. acnes was 4.7 µg/ml. Cathelicidin-BF also effectively killed other microorganisms including Staphylococcus epidermidis, which was possible pathogen for acne vulgaris. Cathelicidin-BF significantly inhibited pro-inflammatory factors secretion in human monocytic cells and P. acnes-induced O2.− production of human HaCaT keratinocyte cells. Observed by scanning electron microscopy, the surfaces of the treated pathogens underwent obvious morphological changes compared with the untreated controls, suggesting that this antimicrobial peptide exerts its action by disrupting membranes of microorganisms. The efficacy of cathelicidin-BF gel topical administering was evaluated in experimental mice skin colonization model. In vivo anti-inflammatory effects of cathelicidin-BF were confirmed by relieving P. acnes-induced mice ear swelling and granulomatous inflammation. The anti-inflammatory effects combined with potent antimicrobial activities and O2.− production inhibition activities of cathelicidin-BF indicate its potential as a novel therapeutic option for acne vulgaris

Odorranalectin Is a Small Peptide Lectin with Potential for Drug Delivery and Targeting

BACKGROUND: Lectins are sugar-binding proteins that specifically recognize sugar complexes. Based on the specificity of protein-sugar interactions, different lectins could be used as carrier molecules to target drugs specifically to different cells which express different glycan arrays. In spite of lectin's interesting biological potential for drug targeting and delivery, a potential disadvantage of natural lectins may be large size molecules that results in immunogenicity and toxicity. Smaller peptides which can mimic the function of lectins are promising candidates for drug targeting. PRINCIPAL FINDINGS: Small peptide with lectin-like behavior was screened from amphibian skin secretions and its structure and function were studied by NMR, NMR-titration, SPR and mutant analysis. A lectin-like peptide named odorranalectin was identified from skin secretions of Odorrana grahami. It was composed of 17 aa with a sequence of YASPKCFRYPNGVLACT. L-fucose could specifically inhibit the haemagglutination induced by odorranalectin. (125)I-odorranalectin was stable in mice plasma. In experimental mouse models, odorranalectin was proved to mainly conjugate to liver, spleen and lung after i.v. administration. Odorranalectin showed extremely low toxicity and immunogenicity in mice. The small size and single disulfide bridge of odorranalectin make it easy to manipulate for developing as a drug targeting system. The cyclic peptide of odorranalectin disclosed by solution NMR study adopts a beta-turn conformation stabilized by one intramolecular disulfide bond between Cys6-Cys16 and three hydrogen bonds between Phe7-Ala15, Tyr9-Val13, Tyr9-Gly12. Residues K5, C6, F7, C16 and T17 consist of the binding site of L-fucose on odorranalectin determined by NMR titration and mutant analysis. The structure of odorranalectin in bound form is more stable than in free form. CONCLUSION: These findings identify the smallest lectin so far, and show the application potential of odorranalectin for drug delivery and targeting. It also disclosed a new strategy of amphibian anti-infection

Analysis of transient heat source and coupling temperature field during cold strip rolling

In the process of cold thin strip rolling, the effect of the roll gap heat source on the transient temperature of cold rolled strip is very significant, and especially for the lateral temperature difference fluctuation which easily leads to the additional shape deviation of the rolled strip. In this study, according to the new heat resource model, the coupled temperature field model with high precision can be established, and the influence of the heat resource on the transient temperature of the cold rolled strip can be obtained by comprehensively considering the emulsion heat transfer coefficient, the air cooling, and the heat conduction boundary conditions. Based on the above models and the actual working parameters, several cases were performed to show the detailed analyses of the transient temperature distributions under various rolling conditions. The results at different strip positions show that the lateral distributions of the roll gap heat source and the strip transient temperature at every stand or pass can be simulated well. This study can improve the calculation precision of the transient lateral temperature difference for the complex online shape deviations during cold thin strip rolling

Optimisation of additives on the performance of loess/fly ash-based ceramic membrane supports

Inorganic ceramic membranes have received a lot of attention due to their resistance to acid and alkali corrosion and ease of cleaning and utilisation, however, their high cost has limited their widespread use. To obtain lower-cost ceramic membranes with better performance, in this paper, single-channel tubular ceramic membrane supports were prepared using natural loess and solid waste fly ash as raw materials. This paper firstly investigated the effects of various additives (including carboxymethyl cellulose (CMC), graphite, calcium carbonate, copper oxide, magnesium oxide, and manganese dioxide,) on the pore size distribution, pure water flux, and flexural strength of the supports to select the appropriate additives; secondly, the response surface methodology was used to determine the amount of each parameter to be added. The results showed that CMC was more viscous and malleable compared to graphite and CaCO _3 , thus increasing the density and pure water flux of the supports. MnO _2 improved both the pure water flux and flexural strength of the supports compared to CuO and MgO. The best sample was obtained when the contents of CMC, MnO _2 , and kaolinite were 9.85 wt%, 10.62 wt%, and 4.8 wt%, respectively, the best sample obtained exhibited a pure water flux of 4985.52 L·m ^−2 ·h ^−1 ·MPa ^−1 and a flexural strength of 45.4 MPa. The support obtained meets the conditions for the application of porous ceramic carriers and provides a viable pathway for the wide application of low-cost ceramic membrane carriers