Hybrid dendritic computing with kernel-LICA applied to Alzheimer's disease detection in MRI

Dendritic computing has been proved to produce perfect approximation of any data distribution. This result guarantees perfect accuracy training. However, we have found great performance degradation when tested on conventional k-fold cross-validation schemes. In this paper we propose to use Lattice Independent Component Analysis (LICA) and the Kernel transformation of the data as an appropriate feature extraction that improves the generalization of dendritic computing classifiers. We obtain a big increase in classification performance applying with this schema over a database of features extracted from Magnetic Resonance Imaging (MRI) including Alzheimer's disease (AD) patients and control subjects.     

台缘斜坡带变形膏、盐岩下的礁体识别技术

阿姆河盆地中石油合作区块在中、晚侏罗世沉积时期在台缘斜坡带发育大量的生物礁与巨厚的膏、盐岩沉积,形成了该区重要的储盖组合类型。由于后期受西南吉萨尔山逆冲的影响,膏、盐岩地层发生了形变与塑性流动,影响了盐下礁体的识别。针对台缘斜坡带大量分布的点礁与上覆膏、盐岩变形关系,本文从地震正演模型入手,分析两者的地震响应特征;利用时差厚度方法进行生物礁的识别;探索出古地貌与相干振幅属性相结合的方法预测生物礁储层的分布;利用优选层序格架约束稀疏反演方法,有效地消除膏、盐岩变形对生物礁储层的影响。形成了一套基于膏、盐岩变形下的礁体识别方法,提高了礁体识别精度,发现一批可供钻探的生物礁。     

Towards the integration of dark- and photo-fermentative waste treatment. 3. Potato as substrate for sequential dark fermentation and light-driven H2 production

The goal of the study was to characterize H₂ production in an integrated process utilizing potato homogenate (PH) for dark, fermentative H₂ production followed by H₂ photoproduction using purple non-sulfur bacteria. Emphasis was placed on (a) examining potato fermentation effluent (FE) as substrate for H₂ photoproduction, (b) estimating the yield and efficiency of both processes, and (c) elucidating the physiological factors influencing the integrated system as a whole. In the dark stage maximal production of gas (11.5 L L⁻¹ of the culture) and VFA (350 mM) were observed with a PH concentration of 400 g L⁻¹ of medium, but higher yields (0.05 L g⁻¹ PH; 1.9 mmol g⁻¹ PH) were obtained at PH concentrations of 50–100 g L⁻¹. H₂ photoproduction by purple bacteria was inhibited at high FE content. Upon suitable dilution, adequate illumination, and supplementation with Fe/Mg/phosphate nutrients, H₂ photoproduction reached 40 L L⁻¹ of non-diluted FE, with a total H₂ yield of 5.6 mol mol⁻¹ glucose equivalent for the two-stage integrated process.     

Fertilisation and pesticides affect mandarin orange nutrient composition

The effects of the application of foliar fertilisation and pesticide on nutritional quality of mandarin orange juices were evaluated using ¹H NMR metabolomics. Significant differences between the use of fertiliser and pesticides during fruit formation were observed, and included changes in sugar, amino acid and organic acid composition. To determine whether the difference in sugar concentration was enough for the consumer to detect, a sensory experiment was performed in which two orange juice samples were prepared to resemble the sweet/sour taste balance of juice from mandarin oranges in which foliar fertilisation was either applied or not. In a test using non-trained individuals, 68% could correctly identify which juice had a sourer, or less sweet, taste. The implications of this study could impact citrus growers, and ultimately aid in development of fruit with superior sensory quality.     

Kaiso Regulates DNA Methylation Homeostasis

Gain and loss of DNA methylation in cells is a dynamic process that tends to achieve an equilibrium. Many factors are involved in maintaining the balance between DNA methylation and demethylation. Previously, it was shown that methyl-DNA protein Kaiso may attract NCoR, SMRT repressive complexes affecting histone modifications. On the other hand, the deficiency of Kaiso resulted in reduced methylation of ICR in H19/Igf2 locus and Oct4 promoter in mouse embryonic fibroblasts. However, nothing is known about how Kaiso influences DNA methylation at the genome level. Here we show that deficiency of Kaiso led to whole-genome hypermethylation, using Kaiso deficient human renal cancer cell line obtained via CRISPR/CAS9 genome editing. However, Kaiso serves to protect genic regions, enhancers, and regions with a low level of histone modifications from demethylation. We detected hypomethylation of binding sites for Oct4 and Nanog in Kaiso deficient cells. Kaiso immunoprecipitated with de novo DNA methyltransferases DNMT3a/3b, but not with maintenance methyltransferase DNMT1. Thus, Kaiso may attract methyltransferases to surrounding regions and modulate genome methylation in renal cancer cells apart from being methyl DNA binding protein.     

Reagentless biosensor based on glucose oxidase wired by the mediator freely diffusing in enzyme containing membrane

Wiring glucose oxidase in the membrane with an immobilized mediator is possible due to the diffusion ability of the latter, if the enzyme containing membrane is formed according to the proposed protocol, including exposing proteins to water-organic mixtures with the high content of organic solvent. In the course of the study, the new glucose oxidase mediator, unsubstituted phenothiazine, was discovered. The diffusion coefficient of the mediator in the resulting membrane is independent of the presence of enzyme. The cyclic voltammograms of the enzyme electrode after appearance of the only glucose in solution obtain a well-defined catalytic shape, which is normally observed for both the enzyme and the mediator in solution. Analytical performances of the resulting biosensor are comparable to the advanced second generation ones, which, however, require covalent linking of the mediator either to the membrane forming polymer or to the enzyme. Even without such covalent linking, the reported biosensor is characterized by an appropriate long-term operational stability allowing reagentless sensing.     

Caput Ligation Renders Immature Mouse Sperm Motile and Capable to Undergo cAMP-Dependent Phosphorylation

Mammalian sperm must undergo two post-testicular processes to become fertilization-competent: maturation in the male epididymis and capacitation in the female reproductive tract. While caput epididymal sperm are unable to move and have not yet acquired fertilization potential, sperm in the cauda epididymis have completed their maturation, can move actively, and have gained the ability to undergo capacitation in the female tract or in vitro. Due to the impossibility of mimicking sperm maturation in vitro, the molecular pathways underlying this process remain largely unknown. We aimed to investigate the use of caput epididymal ligation as a tool for the study of sperm maturation in mice. Our results indicate that after seven days of ligation, caput sperm gained motility and underwent molecular changes comparable with those observed for cauda mature sperm. Moreover, ligated caput sperm were able to activate pathways related to sperm capacitation. Despite these changes, ligated caput sperm were unable to fertilize in vitro. Our results suggest that transit through the epididymis is not required for the acquisition of motility and some capacitation-associated signaling but is essential for full epididymal maturation. Caput epididymal ligation is a useful tool for the study of the molecular pathways involved in the acquisition of sperm motility during maturation.     

Comprehensive Cytokine Profiling of Patients with COVID-19 Receiving Tocilizumab Therapy

Coronavirus disease 2019 (COVID-19) is characterized by immune activation in response to viral spread, in severe cases leading to the development of cytokine storm syndrome (CSS) and increased mortality. Despite its importance in prognosis, the pathophysiological mechanisms of CSS in COVID-19 remain to be defined. Towards this goal, we analyzed cytokine profiles and their interrelation in regard to anti-cytokine treatment with tocilizumab in 98 hospitalized patients with COVID-19. We performed a multiplex measurement of 41 circulating cytokines in the plasma of patients on admission and 3–5 days after, during the follow-up. Then we analyzed the patient groups separated in two ways: according to the clusterization of their blood cytokines and based on the administration of tocilizumab therapy. Patients with and without CSS formed distinct clusters according to their cytokine concentration changes. However, the tocilizumab therapy, administered based on the standard clinical and laboratory criteria, did not fully correspond to those clusters of CSS. Furthermore, among all cytokines, IL-6, IL-1RA, IL-10, and G-CSF demonstrated the most prominent differences between patients with and without clinical endpoints, while only IL-1RA was prognostically significant in both groups of patients with and without tocilizumab therapy, decreasing in the former and increasing in the latter during the follow-up period. Thus, CSS in COVID-19, characterized by a correlated release of multiple cytokines, does not fully correspond to the standard parameters of disease severity. Analysis of the cytokine signature, including the IL-1RA level in addition to standard clinical and laboratory parameters may be useful to define the onset of a cytokine storm in COVID-19 as well as the indications for anti-cytokine therapy.     

Active Learning with Bootstrapped Dendritic Classifier applied to medical image segmentation

We perform the segmentation of medical images following an Active Learning approach that allows quick interactive segmentation minimizing the requirements for intervention of the human operator. The basic classifier is the Bootstrapped Dendritic Classifier (BDC), which combine the output of an ensemble of weak Dendritic Classifiers by majority voting. Weak Dendritic Classifiers are trained on bootstrapped samples of the train data setting a limit on the number of dendrites. We validate the approach on the segmentation of the thrombus in 3D Computed Tomography Angiography (CTA) data of Abdominal Aortic Aneurysm (AAA) patients simulating the human oracle by the provided ground truth. The generalization results in terms of accuracy and true positive ratio of the classification of the entire volume by the classifier trained on one slice confirm that the approach is worth its consideration for clinical practice.