Image mining approaches for the screening of age-related macular degeneration

Age-related Macular Degeneration (AMD) is the most common cause of irreversible vision loss in those aged over 50. In this chapter we investigating two techniques to support automated AMD screening. First of all we conceptualise AMD screening in terms of a binary classification problem (disease v. no-disease). We then propose and compare two very different techniques whereby the desired classification can be undertaken. The first is founded on a histogram based retinal image representation and the second on a graph based representation. In the histogram based approach each image is defined in terms of a histograms that in turn is presented as "time series curves". Given a training set (a collection of labelled positive and negative examples) we create a Case Base (CB) of labelled curves to which a Case Based Reasoning (CBR) mechanism is applied so as to classify "unseen" images according to whether they feature AMD or not. Curve comparison is conducted using a time series comparison technique. For the graph mining based approach a hierarchical decomposition technique is proposed, whereby pre-labelled retinal images contained in a training set, are successively decomposed into smaller and smaller segments until each segment describes a uniform set of features. The resulting decomposition is stored in a tree structure, one per image, to which a frequent sub-graph (sub-tree) mining technique is applied so as to identify the frequently occurring sub-trees that exist within the overall tree data set. The identified sub-trees then form the global attribute set from which a collection of feature vectors (one per image) is derived so as to describe the training set. A standard classifier generator is then applied to this feature vector representation to produce the desired classifier. The two approaches are compared and evaluated using two publicly available data sets, ARIA and STARE, respectively comprising 161 and 97 pre-labelled retinal images. The paper details both approaches and reports on their evaluation

Spin State Disproportionation in Insulating Ferromagnetic LaCoO3 Epitaxial Thin Films

The origin of insulating ferromagnetism in epitaxial LaCoO3 films under tensile strain remains elusive despite extensive research efforts have been devoted. Surprisingly, the spin state of its Co ions, the main parameter of its ferromagnetism, is still to be determined. Here, we have systematically investigated the spin state in epitaxial LaCoO3 thin films to clarify the mechanism of strain induced ferromagnetism using element-specific x-ray absorption spectroscopy and dichroism. Combining with the configuration interaction cluster calculations, we unambiguously demonstrate that Co3+ in LaCoO3 films under compressive strain (on LaAlO3 substrate) are practically a low spin state, whereas Co3+ in LaCoO3 films under tensile strain (on SrTiO3 substrate) have mixed high spin and low spin states with a ratio close to 1:3. From the identification of this spin state ratio, we infer that the dark strips observed by high-resolution scanning transmission electron microscopy indicate the position of Co3+ high spin state, i.e., an observation of a spin state disproportionation in tensile-strained LaCoO3 films. This consequently explains the nature of ferromagnetism in LaCoO3 films

Autotoxins in continuous tobacco cropping soils and their management

Tobacco belongs to the family Solanaceae, which easily forms continuous cropping obstacles. Continuous cropping exacerbates the accumulation of autotoxins in tobacco rhizospheric soil, affects the normal metabolism and growth of plants, changes soil microecology, and severely reduces the yield and quality of tobacco. In this study, the types and composition of tobacco autotoxins under continuous cropping systems are summarized, and a model is proposed, suggesting that autotoxins can cause toxicity to tobacco plants at the cell level, plant-growth level, and physiological process level, negatively affecting soil microbial life activities, population number, and community structure and disrupting soil microecology. A combined strategy for managing tobacco autotoxicity is proposed based on the breeding of superior varieties, and this approach can be combined with adjustments to cropping systems, the induction of plant immunity, and the optimization of cultivation and biological control measures. Additionally, future research directions are suggested and challenges associated with autotoxicity are provided. This study aims to serve as a reference and provide inspirations needed to develop green and sustainable strategies and alleviate the continuous cropping obstacles of tobacco. It also acts as a reference for resolving continuous cropping challenges in other crops

Development, optimization and <i>in vitro</i> evaluation of norcantharidin loadedself-nanoemulsifying drug delivery systems (NCTD-SNEDDS)

<p>This study focused on developing a self-nanoemulsifying drug delivery system (SNEDDS) containing bioactive surfactants under an efficient screening approach for overcoming problems associated with the delivery of norcantharidin (NCTD), a high dose chemotherapy agent having pH dependent solubility. Preliminary screening was implemented to select proper components combination. Besides the solubility of NCTD in the oil phase, emulsifying efficiency, droplet size and size distribution were also employed to select components of the SNEDDS. Moreover, the influence of surfactant and co-surfactant on the interfacial tension and droplets of nanoemulsions were investigated to further understand the mechanism of spontaneous emulsification. Co-surfactant addition promoted the emulsification via reducing the water/oil interfacial tension and viscosity. Ternary phase diagrams were constructed to investigate the phase behavior and designate the optimum systems. The alternative formulations were characterized for cloud point, dilution robustness, droplet size, polydispersity index (PDI) and transmission electron microscopy (TEM). <i>In vitro</i> dissolution study showed that the dissolution rate of optimized formulation (NCTD 10 mg/g, EO 50 wt.%, Cremophor EL 35 wt.%, ethylene glycol 15 wt.%) was slower than drug suspension under the same conditions, confirming that the developed SNEDDS formulation would exhibit sustained release potential.</p

Protectin D1 alleviates cardiac ischemia-reperfusion injury in rats by up-regulating GPR37/JNK/PPAR-γ signaling pathway in cardiac macrophages

Objective To investigate the mechanism by which protectin D1 (PD1) alleviates cardiac ischemia-reperfusion (IR) injury via GPR37/JNK/PPAR-γ signaling pathway. Methods Male adult SD rats (6-8 weeks old) were randomly divided into sham-operation group, IR group, IR+PD1 group, and IR+PD1+ cytochalasin B (CB) group. In the latter 3 groups, the rats were subjected to daily intraperitoneal injections of normal saline, PD1 (100 nmol/L), or PD1 and CB for consecutive 3 days before establishment of cardiac IR injury models. At 6, 24, and 48 h and at 2 weeks after the surgery, the hearts and blood samples were collected from each group, and the cardiac macrophages were isolated and cultured. The cardiac pathologies, changes in cardiac enzyme profile, cardiac fibrosis, serum inflammatory factors, phagocytic function of the cardiac macrophages, changes in the cell polarity, and the expressions of inflammatory factors and GPR37/JNK/ PPAR-γ signaling pathway in cultured cardiac macrophages were detected. Results In the rats with cardiac IR injury, PD1 treatment significantly alleviated the cardiac pathologies, lowered the expressions of the cardiac enzymes (P < 0.05), decreased the serum levels of IL-1β, TNF-α, and IL-6 while increased the serum levels of IL-10 and TGF-β (P < 0.05). In the cultured cardiac macrophages, PD1 treatment significantly enhanced their phagocytosis of the apoptotic cells (P < 0.05) and M2-type polarization (P < 0.05), decreased the expressions of IL-1β, TNF-α, IL-6, and increased the expressions of IL-10 and TGF-β (P < 0.05) and the expressions of GPR37, IRE1α, ATF6, PERK, p-JNK, and PPAR-γ (P < 0.05). Conclusion PD1 can alleviate cardiac IR injury in rats possibly by up-regulating the GPR37/JNK/PPAR-γ signaling pathway to enhance the phagocytic activity of the cardiac macrophages and the expressions of the anti-inflammatory factors

Study on Adsorption of Heavy Metals Cu and Zn by Microplastics Under Different Aged Factors

Microplastics are widely distributed in a variety of environments, absorbing heavy metals in the environment while aging due to various environmental factors. In this paper, the effects of different aging factors (pH, DOM, and H2O2) on the adsorption capacity of heavy metals Cu and Zn on polyethylene microplastics (PE-MPs) were investigated, and the changes in physical and chemical properties of PE microplastics were analyzed. The results demonstrate that H2O2 aging bears the greatest effect on the adsorption effect of PE microplastics, dissolved organic matter (DOM) aging has the least effect on the adsorption effect of PE microplastics, and the adsorption effect of microplastics aged with pH=9 is stronger than that aged with pH=4; the adsorption kinetics model of microplastics fitted to the pseudo-second-order kinetic model, and the thermodynamic model fitted to Langmuir model; aging mainly changed the surface structure of microplastics, increased the Zeta potential of microplastics, introduced more oxygen-containing functional groups, and finally affected the ability of microplastics to adsorb heavy metals. The research provides data reference for understanding the influence of different aging on the adsorption capacity of heavy metals in microplastics