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Framing coworking spaces marketing strategies via social media indices

100%

Vagianos D. , Koutsoupias N.

nr 2

1-14

In this paper an investigation of social media marketing techniques of Coworking spaces’ type of business is performed, using datasets acquired using social media monitoring tools. Mediatoolkit has been used to scrap data deriving from the activity of the WeWork Instagram and Twitter accounts which were collected on a 24/7 basis from varying locations and in multiple languages in a fifteen-day time window. Indices related to sentiment, reach, influence, number of followers, retweets, likes, comments, and view scores formed the datasets that were examined by applying multiple correspondence analysis as well as the hierarchical clustering method. The aim of this paper was to explore the inherent properties of the multiple indices describing the general realm of social media marketing tools, and more specifically aspires to provide digital marketers with an alternative perspective of social media marketing strategies related to the emerging coworking spaces type of business. The authors identified three classes/segments of posts, whereas post polarity tends to relate to geographic location, regardless of the social media channel used for posting.

The PROMETHEE II method in multi-criteria evaluation of cryptocurrency exchanges

100%

Kadziolka K.

nr 2

A Comparison of Antioxidant, Antibacterial, and Anticancer Activity of the Selected Thyme Species by Means of Hierarchical Clustering and Principal Component Analysis

75%

Orłowska M. , Pytlakowska K. , Mrozek-Wilczkiewicz A. , Musioł R. , Waksmundzka-Hajnos M. , Sajewicz M. , Kowalska T.

2016

tom Vol. 28, no. 2

207--221

In this study, six numerical data sets are presented valid for eighteen thyme (Thymus L.) species and characterizing three biological properties of these herbs, i.e., antioxidant, antibacterial, and anticancer activity. Four data sets characterize antioxidant properties, one data set characterizes antibacterial property, and one data set characterizes anticancer activity. Antioxidant properties were measured with two free radical standards (DPPH and ABTS), two free radical scavenger standards (trolox and gallic acid), and three analytical techniques (EPR spectroscopy, ultraviolet–visible [UV–vis] spectrophotometry, and the dot blot test with bioautographic detection). Antibacterial activity was tested upon the Gram-positive Bacillus subtilis (ATCC 6633) strain, and anticancer activity was evaluated upon the human colon adenocarcinoma cells (HCT116). It was found out that the thyme extracts characterize with all three biological activities (yet with anticancer activity not very strongly pronounced) and that in quantitative terms, each activity strongly depends on the thyme species considered. An ultimate goal of this study was to investigate if any quantitatively confirmed correlation exists among these three biological activities, which might point out to a common mechanism of their action. To this effect, six sets of numerical data underwent hierarchical clustering and Principal Component Analysis. Based on the results obtained, no quantitative correlation was established among antioxidant, antibacterial, and anticancer activity of the thyme species, which seems indicative of different molecular mechanisms of these three actions.

Redox state of plastoquionone pool regulates expression of Arabidopsis thaliana genes in response to elevated irradiance

75%

Adamiec M. , Drath M. , Jackowski G.

tom 55

nr 1

DNA microarray technology was applied to gain insight into the role of the redox state of PQ pool as a retrograde factor mediating differential expression of Arabidopsis nuclear genes during the acclimation to changing irradiance. DNA microarray chips containing probes corresponding to 24000 Arabidopsis nuclear genes were screened with cRNA samples prepared from leaves of plants exposed for 5 h to low irradiance (control) vs. medium, high and excessive irradiances (MI, HI and EI, respectively). Six hundred and sixty three genes were differentially expressed as a result of an exposure to at least one elevated irradiance. Among 663 differentially expressed genes a total of 50 were reverted by DCMU - 24 ones modulated at medium irradiance, 32 ones modulated at high irradiance and a single one modulated at excessive irradiance. We postulate that their expression is regulated by redox state of plastoquinone (PQ) pool. Thus the PQ-mediated redox regulation of expression of Arabidopsis nuclear genes is probably limited to the irradiance window representing non-stressing conditions. We found that the promoter regions of the PQ-regulated genes contained conserved elements, suggesting transcriptional control by a shared set of trans-acting factors which participate in signal transduction from the redox state of the PQ pool.