Antioxidant and cytotoxic potential of selected plant species of the boraginaceae family

Antioxidant activity is one of the most important properties of plant extracts. Antioxidants from natural sources have been intensively studied in the last few decades. The antioxidant contents of medicinal plants may contribute to the protection of diseases. Bioactive components of plants have a potential role in chemoprevention and inhibition of different phases of the malignant transformation process. Therefore, plant extracts and essential oils are in the focus of research, and in recent decades have been tested on a large number of malignant cell lines. The aim of this study was to examine antioxidant and cytotoxic potential of selected plant species from the Boraginaceae family. Determination of antioxidant activity was performed by ammonium-thiocyanate method. Testing citotoxic activity was performed by MTT test on cancer cell lines: HEP 2c (human larynx carcinoma), RD (human cell line-rhabdomyosarcoma) and L2OB (mouse tumor fibroblast line). The best antioxidant activity showed ethanol, acetone and chloroform extracts of Anchusa officinalis, Echium vulgare and Echium italicum. The tested extracts showed an inhibitory effect on cancer cells, but chloroform and acetone extracts of all three plant had the most effective effect on L2OB cells. Isolation of individual active components from this plants and their testing for cancer cells would be of great importance for this field of research

Length and clinical effectiveness of pulmonary rehabilitation in outpatients with chronic airway obstruction

Study objective: To assess the clinical effectiveness of pulmonary rehabilitation (PR) after 10 or 20 consecutive sessions in outpatients with chronic airway obstruction (CAO). Design: Observational prospective cohort trial. Setting: Outpatient clinic of a rehabilitation center. Patients and interventions: Twenty-five outpatients (mean age, 65 +/- 9 years [+/- SD]; FEV1, 64 +/- 12% predicted) admitted to a comprehensive PR program, including exercise training. Measurements and results: The load reached on a cycloergometer (maximal achieved load [W-max]), the maximal and isoload dyspnea and leg fatigue on a Borg scale, 6-min walk distance (6MWD), and the health-related quality of life as assessed using the St. George's Respiratory Questionnaire (SGRQ) [total and components score] have been recorded as outcome measures at baseline, after 10 sessions (T10), and after 20 sessions (T20). The predefined criteria of the clinically significant improvement were as follows: + 15% W-max, + 54 m at 6MWD, - 1 point at isoload dyspnea and leg fatigue, and - 4% at SGRQ scores. There was a mean significant difference between changes at T20 and T10 for 6MWD (- 42.96 m; 95% confidence interval [0], - 57.79 to - 28.12 m; p = 0.001), total SGRQ (4.80; 95% CI, 2.29 to 7.31; p = 0.001), activity SGRQ (3.60; 95% CI, 0.48 to 6.71; p = 0.025), and symptoms SGRQ (5.96; 95% CI, 2.72 to 9.2; p = 0.001). The percentage of patients who improved was different at T20 as compared with T 10 for W-max (68% and 48%, respectively; p = 0.025), 6MWD (76% and 20%, p = 0.001), and total SGRQ (64% and 36%, p = 0.008). Conclusions: A 10-session course of PR provides only limited clinically significant changes of outcome measures when compared with a 20-session course in outpatients with CAO of mild-to-moderate severity

BlinkML: Efficient Maximum Likelihood Estimation with Probabilistic Guarantees

The rising volume of datasets has made training machine learning (ML) models a major computational cost in the enterprise. Given the iterative nature of model and parameter tuning, many analysts use a small sample of their entire data during their initial stage of analysis to make quick decisions (e.g., what features or hyperparameters to use) and use the entire dataset only in later stages (i.e., when they have converged to a specific model). This sampling, however, is performed in an ad-hoc fashion. Most practitioners cannot precisely capture the effect of sampling on the quality of their model, and eventually on their decision-making process during the tuning phase. Moreover, without systematic support for sampling operators, many optimizations and reuse opportunities are lost. In this paper, we introduce BlinkML, a system for fast, quality-guaranteed ML training. BlinkML allows users to make error-computation tradeoffs: instead of training a model on their full data (i.e., full model), BlinkML can quickly train an approximate model with quality guarantees using a sample. The quality guarantees ensure that, with high probability, the approximate model makes the same predictions as the full model. BlinkML currently supports any ML model that relies on maximum likelihood estimation (MLE), which includes Generalized Linear Models (e.g., linear regression, logistic regression, max entropy classifier, Poisson regression) as well as PPCA (Probabilistic Principal Component Analysis). Our experiments show that BlinkML can speed up the training of large-scale ML tasks by 6.26x-629x while guaranteeing the same predictions, with 95% probability, as the full model.Comment: 22 pages, SIGMOD 201

Giant magnetic enhancement in Fe/Pd films and its influence on the magnetic interlayer coupling

The magnetic properties of thin Pd fcc(001) films with embedded monolayers of Fe are investigated by means of first principles density functional theory. The induced spin polarization in Pd is calculated and analyzed in terms of quantum interference within the Fe/Pd/Fe bilayer system. An investigation of the magnetic enhancement effects on the spin polarization is carried out and its consequences for the magnetic interlayer coupling are discussed. In contrast to {\it e.g.} the Co/Cu fcc(001) system we find a large effect on the magnetic interlayer coupling due to magnetic enhancement in the spacer material. In the case of a single embedded Fe monolayer we find aninduced Pd magnetization decaying with distance $n$ from the magnetic layer as ~$n^{-\alpha}$ with $\alpha \approx 2.4$. For the bilayer system we find a giant magnetic enhancement (GME) that oscillates strongly due to interference effects. This results in a strongly modified magnetic interlayer coupling, both in phase and magnitude, which may not be described in the pure Ruderman-Kittel-Kasuya-Yoshida (RKKY) picture. No anti-ferromagnetic coupling was found and by comparison with magnetically constrained calculations we show that the overall ferromagnetic coupling can be understood from the strong polarization of the Pd spacer

Light localization in optically induced deterministic aperiodic Fibonacci lattices

As light localization becomes increasingly pronounced in photonic systems with less order, we investigate optically induced two-dimensional Fibonacci structures that are supposed to be among the most ordered realizations of deterministic aperiodic patterns. For the generation of corresponding refractive index structures, we implement a recently developed incremental induction method using nondiffracting Bessel beams as waveguide formation entities. Even though Fibonacci structures present slightly reduced order, we show that transverse light transport here is significantly hampered in comparison with discrete diffraction in a periodic lattice. Numerical simulations that support our experimental findings help to identify three cases of input waveguide configurations that significantly determine the initial propagation in a Fibonacci structure. These crucial starting conditions determine the character of light transport, yielding either localization or enhanced expansion. A diverse set of light transport scenarios is identified therein

3-D Ultrastructure of O. tauri: Electron Cryotomography of an Entire Eukaryotic Cell

The hallmark of eukaryotic cells is their segregation of key biological functions into discrete, membrane-bound organelles. Creating accurate models of their ultrastructural complexity has been difficult in part because of the limited resolution of light microscopy and the artifact-prone nature of conventional electron microscopy. Here we explored the potential of the emerging technology electron cryotomography to produce three-dimensional images of an entire eukaryotic cell in a near-native state. Ostreococcus tauri was chosen as the specimen because as a unicellular picoplankton with just one copy of each organelle, it is the smallest known eukaryote and was therefore likely to yield the highest resolution images. Whole cells were imaged at various stages of the cell cycle, yielding 3-D reconstructions of complete chloroplasts, mitochondria, endoplasmic reticula, Golgi bodies, peroxisomes, microtubules, and putative ribosome distributions in-situ. Surprisingly, the nucleus was seen to open long before mitosis, and while one microtubule (or two in some predivisional cells) was consistently present, no mitotic spindle was ever observed, prompting speculation that a single microtubule might be sufficient to segregate multiple chromosomes