Endoscopic video manifolds for targeted optical biopsy

Gastro-intestinal (GI) endoscopy is a widely used clinical procedure for screening and surveillance of digestive tract diseases ranging from Barrett's Oesophagus to oesophageal cancer. Current surveillance protocol consists of periodic endoscopic examinations performed in 3-4 month intervals including expert's visual assessment and biopsies taken from suspicious tissue regions. Recent development of a new imaging technology, called probe-based confocal laser endomicroscopy (pCLE), enabled the acquisition of in vivo optical biopsies without removing any tissue sample. Besides its several advantages, i.e., noninvasiveness, real-time and in vivo feedback, optical biopsies involve a new challenge for the endoscopic expert. Due to their noninvasive nature, optical biopsies do not leave any scar on the tissue and therefore recognition of the previous optical biopsy sites in surveillance endoscopy becomes very challenging. In this work, we introduce a clustering and classification framework to facilitate retargeting previous optical biopsy sites in surveillance upper GI-endoscopies. A new representation of endoscopic videos based on manifold learning, "endoscopic video manifolds" (EVMs), is proposed. The low dimensional EVM representation is adapted to facilitate two different clustering tasks; i.e., clustering of informative frames and patient specific endoscopic segments, only by changing the similarity measure. Each step of the proposed framework is validated on three in vivo patient datasets containing 1834, 3445, and 1546 frames, corresponding to endoscopic videos of 73.36, 137.80, and 61.84 s, respectively. Improvements achieved by the introduced EVM representation are demonstrated by quantitative analysis in comparison to the original image representation and principal component analysis. Final experiments evaluating the complete framework demonstrate the feasibility of the proposed method as a promising step for assisting the endoscopic expert in retargeting the optical biopsy sites.     

Evaluation of antioxidant and antimicrobial potential of strawberry tree (<Emphasis Type="Italic">Arbutus Unedo</Emphasis> L.) leaf

In present study, antioxidant and antimicrobial activities of strawberry tree (Arbutus unedo L.) leaves were investigated. Antioxidant activity was determined by methods of DPPH scavenging, β-carotene bleaching, reducing power, metal chelating, superoxide anion scavenging, and hydrogen peroxide scavenging activity. Total phenolic content were determined to be 197.16±1.43 mg GAE/g extract in aqueous extract. The EC₅₀ value of methanolic extracts was found to be 0.423 mg/mL. The extracts of leaves showed nearly 1/4 metal chelating capacity of standard EDTA, high reducing power, superoxide anion scavenging, and hydrogen peroxide scavenging activities. While the strawberry tree leaves exhibited antibacterial activity against Staphylococcus aureus, there was no inhibitory effect against Escherichia coli and Salmonella enteritidis. The strawberry tree leaves exhibited antifungal effect against 2 aflatoxigenic molds namely Aspergillus parasiticus NRRL 2999 and NRRL 465. These results suggest that the strawberry tree leaves may be used as an antioxidant source for pharmaceutical application, nutraceutical and functional food industries.     

Antioxidant Potential of Different Dill (Anethum Graveolens L.) Leaf Extracts

Dill (Anethum graveolens L.) have been extensively used in salads, soups, and pickles for its aromatic odor and flavor. Recently, interest in plant-derived food additives has grown. In this study, the possible antioxidant properties of water, ethanol, and acetone extracts of dill leaves were investigated. In order to evaluate antioxidant activities of all extracts, different antioxidant tests were used, such as total antioxidant activity by ferric thiocyanate method, reducing power, DPPH (1,1-diphenyl-2-picryl-hydrazyl) free radical scavenging, hydrogen peroxide scavenging, and ferrous ions chelating activities. The content of phenolic compounds was also determined to be the gallic acid equivalent. Among the three extracts, the water extract of dill leaf showed the most potent antioxidative capacity in each assay, showing 79.66% (at 1 mg/mL) in the DPPH^? radical scavenging activity, 63% (at 800 μg/mL) in the metal chelating effect, 60% (at 400 μg/mL) in the H₂O₂ scavenging activity, and 0.61 absorbance (at 1 mg/mL) in the reducing power.     

Sealing ability and adaptation of root‐end filling materials in cavities prepared with different techniques

The aim of this study was to evaluate the sealing ability and marginal adaptation of calcium silicate‐based cements (CSCs) in root‐end cavities prepared by ultrasonic and laser tips. A total of 72 extracted human maxillary incisor teeth were randomly divided as 60 teeth in experimental groups and 6 teeth each for positive and negative control groups. Specimens in experimental groups were obturated, their root‐end resections were performed and randomly divided into six groups (n = 10) as follows: G1: Ultrasonic retrotip + MTA, G2: Ultrasonic retrotip + Calcium Enriched Mixture (CEM), G3: Ultrasonic retrotip + Biodentine, G4: Er:YAG laser tip + MTA, G5: Er:YAG laser tip + CEM, G6: Er:YAG laser tip + Biodentine. The sealing ability was measured by fluid transport method. Six specimens from each experimental group were randomly selected to analyze marginal adaptation and prepared for scanning electron microscopy (SEM) analysis. Micrographs were scored and also analyzed using Image J software. Data were analyzed with; two‐way ANOVA, Bonferroni, Kruskall–Wallis, Mann–Whitney‐U, Siegel & Castellan, and Spearman correlation coefficient tests. No significant difference was found between materials regarding the sealing ability and marginal adaptation (p > 0.05). Significantly greater fluid movement and poor marginal adaptation were seen for materials placed in cavities prepared by laser tips (p < 0.05). Positive correlation was found between the results of scoring and Image J analysis of SEM images (r = 0.596, p < 0.001). Fluid transport method and SEM analysis gave similar results suggesting the use of ultrasonic‐retrotips for preparing root‐end cavities which are going to be filled with one of these CSCs.     

Production of graphene layer by liquid-phase exfoliation with low sonication power and sonication time from synthesized expanded graphite

Multi-layer graphene was produced through synthesized expanded graphite (EG) liquid exfoliation using organic solvent. Hexagonal graphite (HG) was used as a starting material. HG was mixed with an acidic mixture, dried, rand subjected to thermal treatment. After this process, EG was obtained. This obtained EG was sonicated for 1 h via an ultrasonic homogenizer by blending an organic solvent. Samples were subjected to SEM, TEM, FTIR, and UV-Vis/NIR spectroscopy investigations. After the investigations, it was shown that nano-size graphene sheets were obtained.     

ART HISTORY AND ARCHITECTURAL SYMBOLISM: A Hermeneutical Critique

I propose that the symbolic in general, and especially the symbolic in art, rests upon an intricate interplay of showing and concealing.¹

In Truth and Method Gadamer views the study of history from a hermeneutical perspective, presenting a new way of dealing with and understanding historical texts. He sees the wholeness of a historical tradition as an illusion, He argues that the split between the self-conscious historical object and the observer cannot be clear cut. Accordingly, both the historicity of understanding and the prejudices of the observer play important roles in the interpretation process. With reference to Gadamer's revision of the ‘reality of history’ and the ‘reality of historical understanding,’ this paper aims to examine the art historical discourse on Islamic architecture by concentrating on a specific article. Oleg Grabar's “Symbols and Signs in Islamic Architecture.”     

Degradation Kinetics of Bioactive Compounds and Change in the Antioxidant Activity of Wild Strawberry (Fragaria vesca) Pulp During Heating

This study determined the effect of heat treatment on bioactive compounds (total monomeric anthocyanins and total phenolics) and the visual colour of wild strawberry (Fragaria vesca) pulp within the temperature range 60–90 °C. The change in the antioxidant activities of the samples was also evaluated. Total monomeric anthocyanins and total phenolics degraded with increasing temperature and time. First-order kinetic models were determined for those reactions. The activation energies for the degradation of total monomeric anthocyanins and total phenolics were 21.6 and 18.95 kJ mol^?1, respectively. The change in visual colour of wild strawberry pulp was also determined using CIE L*a*b* colour parameters. The change in colour parameters also followed first-order reaction kinetics. Activation energies for the variation of colour parameters were within the range 11.92–63.23 kJ mol^?1. The antioxidant activities of heated wild strawberry pulp increased with increasing temperature and time.     

RAKE Receiver for Channels with a Sparse Impulse Response

We derive the optimal receiver for RAKE diversity combining on channels with a sparse impulse response. The receiver is based on the Bayesian philosophy and thus it requires the knowledge of certain a priori parameters. However, we also derive an empirical Bayesian version of our receiver, which does not require any a priori knowledge, nor the choice of any user parameters. We show that both versions of our detector can outperform a classical training-based maximum-ratio-combining detector.     

Linear Regression With a Sparse Parameter Vector

We consider linear regression under a model where the parameter vector is known to be sparse. Using a Bayesian framework, we derive the minimum mean-square error (MMSE) estimate of the parameter vector and a computationally efficient approximation of it. We also derive an empirical-Bayesian version of the estimator, which does not need any a priori information, nor does it need the selection of any user parameters. As a byproduct, we obtain a powerful model ("basis") selection tool for sparse models. The performance and robustness of our new estimators are illustrated via numerical examples