Efecto sobre la oxidación de triglicéridos purificados del aceite de girasol, del extracto de acetona del fruto de Maclura pomifera, de la pomiferina y de la osajina

omiferin and osajin have been isolated from the acetonic extract of M. pomifera fruits. Effects of total acetonic extract, pomiferin and osajin on the autooxidation of purified sunflower triacylglycerol were studied. Pomiferin showed a high antioxidant activity whereas total acetonic extract showed moderate and osajin revealed a low activity.Se han aislado la pomiferina y la osajina del extracto de hexano del fruto de M. pomifera. Se han estudiado los efectos sobre la oxidación de triglicéridos purificados del aceite de girasol, del extracto de acetona, de la pomiferina y de la osajina. La pomiferina mostró una actividad antioxidante elevada en cambio, el extracto de acetona mostró una actividad moderada y la osajina baja

An Exploratory Analysis of Twitter Keyword-Hashtag Networks and Knowledge Discovery Applications

The emergence of social media has impacted the way people think, communicate, behave, learn, and conduct research. In recent years, a large number of studies have analyzed and modeled this social phenomena. Driven by commercial and social interests, social media has become an attractive subject for researchers. Accordingly, new models, algorithms, and applications to address specific domains and solve distinct problems have erupted. In this thesis, we propose a novel network model and a path mining algorithm called HashnetMiner to discover implicit knowledge that is not easily exposed using other network models. Our experiments using HashnetMiner have demonstrated anecdotal evidence of drug-drug interactions when applied to a drug reaction context. The proposed research comprises three parts built upon the common theme of utilizing hashtags in tweets. 1 Digital Recruitment on Twitter. We build an expert system shell for two different studies: (1) a nicotine patch study where the system reads streams of tweets in real time and decides whether to recruit the senders to participate in the study, and (2) an environmental health study where the system identifies individuals who can participate in a survey using Twitter. 2 Does Social Media Big Data Make the World Smaller? This work provides an exploratory analysis of large-scale keyword-hashtag networks (K-H) generated from Twitter. We use two different measures, (1) the number of vertices that connect any two keywords, and (2) the eccentricity of keyword vertices, a well-known centrality and shortest path measure. Our analysis shows that K-H networks conform to the phenomenon of the shrinking world and expose hidden paths among concepts. 3 We pose the following biomedical web science question: Can patterns identified in Twitter hashtags provide clinicians with a powerful tool to extrapolate a new medical therapies and/or drugs? We present a systematic network mining method HashnetMiner, that operates on networks of medical concepts and hashtags. To the best of our knowledge, this is the first effort to present Biomedical Web Science models and algorithms that address such a question by means of data mining and knowledge discovery using hashtag-based networks

Kinematic analysis of blocks in tunnel on the basis of discontinuities.

This paper demonstrates the advantages of using stereographic projections in kinematic analysis of rock blocks in excavation surface. The stereographic method is completed by planes and poles as points and lines on the horizontal surface and the block kinematic behavioral analysis is investigated in a rock free face subsequently. A block is considered to be an instable one when the intersection lines fall into the critical zone, this area is defined through the relationship between the friction angle of the stone mass and the slope of the free face respectively. It is possible to determine the movement of the blocks on the basis of the discontinuity position before any collapse or sliding happens

The Use of Talc Powder in Bleaching Cotton Fibers

It is known that the use of sodium silicate (Na2 Si2 O3) in bleaching has some disadvantages such as its high cost, harsh handle of the bleached fabric, and the reduction of the tensile strength of the fabric.Talc Powder is used in the bleaching of woven cotton fabrics as a stabilizer for hydrogen peroxide (H2O2) instead of using sodium silicate. Many experiments were carried out using talc powder at variable condi-tions such as temperature and pH. The same experiments were carried out using sodium silicate stabilizer. Several experiments were carried out on fabrics without a stabilizer.The bleached samples were tested for whiteness, absorbence, and tensile strength. The untreated samples were tested for comparison. The results of the tested samples were recorded and analysed using statistical methods.The study proved that very good whiteness and higher absorbence were obtained when using talc powder, besides that the loss in tensile strength is relatively low. Also it was observed that the softness and handle of fabrics were improved

Video Genre Classification Using Weighted Kernel Logistic Regression

Due to the widening semantic gap of videos, computational tools to classify these videos into different genre are highly needed to narrow it. Classifying videos accurately demands good representation of video data and an efficient and effective model to carry out the classification task. Kernel Logistic Regression (KLR), kernel version of logistic regression (LR), proves its efficiency as a classifier, which can naturally provide probabilities and extend to multiclass classification problems. In this paper, Weighted Kernel Logistic Regression (WKLR) algorithm is implemented for video genre classification to obtain significant accuracy, and it shows accurate and faster good results

Flavonoids as potential anti-MRSA agents through modulation of PBP2a:a computational and experimental study

Recently, the interest in plant-derived antimicrobial agents has increased. However, there are no sufficient studies dealing with their modes of action. Herein, we investigate an in-house library of common plant-based phenolic compounds for their potential antibacterial effects against the methicillin-resistant Staphylococcus aureus (MRSA), a widespread life-threatening superbug. Flavonoids, which are considered major constituents in the plant kingdom, were found to be a promising class of compounds against MRSA, particularly the non-glycosylated ones. On the other hand, the glycosylated derivatives, along with the flavonolignan silibinin A, were able to restore the inhibitory activity of ampicillin against MRSA. To explore the mode of action of this class, they were subjected to an extensive inverse virtual screening (IVS), which suggested penicillin-binding protein 2a (PBP2a) as a possible target that mediates both the antibacterial and the antibiotic-synergistic effects of this class of compounds. Further molecular docking and molecular dynamic simulation experiments were conducted to support the primary IVS and the in vitro results and to study their binding modes with PBP2a. Our findings shed a light on plant-derived natural products, notably flavonoids, as a promising and readily available source for future adjuvant antimicrobial therapy against resistant strains

Photometric and Spectroscopic Analysis of the SX Phe Star BL Cam

In the present paper, we report the photometric and spectroscopic observations obtained by the 1.88 m telescope at the Kottamia astronomical observatory of the pulsating star BL Cam. Fourier analysis of the light curves reveals that the fundamental mode has two harmonics. The O-C method is used to establish the period changes. So far, the analysis has been very successful in mapping the pulsation amplitude of the star across the instability strip. By using the formalism of Eddington and Plakidis (1929), we found significant results and strong indications of the evolutionary period change. A total of 55 new maximum light timings are reported. New values of (1/P) dP/dt are estimated using the O-C diagram based on all newly obtained times of maximum light combined with those taken from the literature, assuming the periods are decreasing and changing smoothly. To compute the effective temperature and surface gravity of the star, we performed model atmosphere analysis on its spectra. The physical parameters of the star are calculated and compared with the evolutionary models