Search Results (5)

The pile-fermentation conditions and raw materials used play a vital role in determining the stability and quality of dark tea. In this study, sensory quality evaluation, metabolomics, and microbiomics techniques were used to investigate the effect of pile-fermentation duration on the taste quality of single-cultivar large-leaf dark tea (SLDT) and its underlying metabolite and microbial mechanisms. The study revealed that a 60-day duration resulted in a better SLDT sensory quality, with astringency and bitterness significantly reduced and sweetness increased. Catechins and theaflavins with ester structures, L-epicatechin, methyl gallate, protocatechuic acid, gallic acid, salicin, chlorogenic acid, and neochlorogenic acid were key taste metabolites contributing to the reduction of astringency and bitterness. Salicylic acid and D-sorbitol helped form the sweetness. Correlation analysis found out Aspergillus, Thermomyces, Bacillus, Staphylococcus, and Micrococcaceae were core functional microorganisms linked to these metabolites, helping to foster the higher quality of SLDT. Microorganisms shaped the taste quality of SLDT through metabolic processes and enzyme secretion during pile-fermentation. This study provided insights into the metabolite basis and microbiological mechanisms of SLDT taste formation and offered guidance for optimizing production processes to improve the stability and quality of dark tea. Full article

Tuberculosis is a potential fatal disease with high morbidity and mortality rates. Tuberculosis death rates are rising, posing a serious health threat in several poor countries around the world. To address this issue, we proposed a novel method for detecting tuberculosis in chest X-ray (CXR) images that uses a three-phased approach to distinguish tuberculosis such as segmentation, feature extraction, and classification. In a CXR, we utilized the Weiner filter to distinguish and reduce the impulse noise. The features were extracted from CXR images and trained using a decision tree classifier known as the stacked loopy decision tree (SLDT) classifier. For the classification process, the ROI-based morphological approach was applied in the mentioned three-phased approach, and the feature extraction was accomplished through chromatic and Prewitt-edge highlights. Full article

Dysregulation of gap junction intercellular communication (GJIC) is recognized as one of the key hallmarks for identifying non-genotoxic carcinogens (NGTxC). Currently, there is a demand for in vitro assays addressing the gap junction hallmark, which would have the potential to eventually become an integral part of an integrated approach to the testing and assessment (IATA) of NGTxC. The scrape loading-dye transfer (SL-DT) technique is a simple assay for the functional evaluation of GJIC in various in vitro cultured mammalian cells and represents an interesting candidate assay. Out of the various techniques for evaluating GJIC, the SL-DT assay has been used frequently to assess the effects of various chemicals on GJIC in toxicological and tumor promotion research. In this review, we systematically searched the existing literature to gather papers assessing GJIC using the SL-DT assay in a rat liver epithelial cell line, WB-F344, after treating with chemicals, especially environmental and food toxicants, drugs, reproductive-, cardio- and neuro-toxicants and chemical tumor promoters. We discuss findings derived from the SL-DT assay with the known knowledge about the tumor-promoting activity and carcinogenicity of the assessed chemicals to evaluate the predictive capacity of the SL-DT assay in terms of its sensitivity, specificity and accuracy for identifying carcinogens. These data represent important information with respect to the applicability of the SL-DT assay for the testing of NGTxC within the IATA framework. Full article

In the present decade, research regarding solar thermal air heaters (SAHs) has noticed a continuous progression in thermo-hydraulic performance augmentation approaches. There now exists a wide variety of thermo-hydraulic performance augmentation approaches and researchers have designated various structures. Nevertheless, there seems to be no generalization to any of the approaches employed. The present numerical investigation reports on the thermo-hydraulic characteristics and thermal performance for flow through a varied length (full, medium, half, and short length) dimple solar air heater (SAH) tube. The study highlights recent developments on enhanced tubes to augment heat transfer in SAH. The influence of different length ratio, dimple height ratio (H), and pitch ratio (s) on thermo-hydraulic characteristics have been investigated in the Reynolds number (Re) range from 5000 to 25,000. Air is used as the working fluid. The commercial software ANSYS Fluent is used for simulation. The shear stress transport (SST) model is used as the turbulence model. Thermal energy transport coefficient is increased in the full-length dimple tube (FLDT), compared to the medium-length dimple tube (MLDT), half-length dimple tube (HLDT) and short-length dimple tube (SLDT). Similarly, the pitch ratio (s) has more influence on Nusselt number (Nu) compared to the dimple height ratio (H). The friction factor decreases with an increase in pitch ratio. Nu increases and f decreases with increasing Re for all combinations of H and s. Low s and higher H yields high enhancement of HT and PD. Integration of artificial roughness on the tube increases the values of Nu and f by 5.12 times and 77.23 times for H = 0.07, s = 1.0 at Re value of 5000 and 25,000, respectively, in regard to the plain tube. For all the tested cases, the thermo-hydraulic performances (η) are greater than unity. Full article

Growing evidence suggests dietary antioxidants reduce the risk of several cancers. Grape seeds extracts (GSE) are a rich source of polyphenols known to have antioxidant, chemopreventive and anticancer properties. Herein, we investigated the in vitro effects and putative action mechanisms of a grape seed extract (GSE) on human breast cancer cells (MCF-7). The effects of GSE were evaluated on cell proliferation, apoptosis and gap-junction-mediated cell-cell communications (GJIC), as basal mechanism involved in the promotion stage of carcinogenesis. GSE (0.05–100 μg/mL) caused a significant dose- and time-dependent inhibition of MCF-7 viability and induced apoptotic cell death, as detected by Annexin-V/Propidium Iodide. Concurrently, GSE induced transient but significant enhancement of GJIC in non-communicating MCF-7 cells, as demonstrated by the scrape-loading/dye-transfer (SL/DT) assay and an early and dose-dependent re-localization of the connexin-43 (Cx43) proteins on plasma membranes, as assayed by immunocytochemistry. Finally, real-time-PCR has evidenced a significant increase in cx43 mRNA expression. The results support the hypothesis that the proliferation inhibition and pro-apoptotic effect of GSE against this breast cancer cell model are mediated by the GJIC improvement via re-localization of Cx43 proteins and up-regulation of cx43 gene, and provide further insight into the action mechanisms underlying the health-promoting action of dietary components. Full article