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The Ophiuchus stream is a short arc-like stellar feature of uncertain origin located $\sim 5$ kpc North of the Galactic centre. New proper motions from the second $Gaia$ data release reconcile the direction of motion of stream members with the stream arc, resolving a puzzling mismatch reported in earlier work. We use N-body simulations to show that the stream is likely only on its second pericentric passage, and thus was formed recently. The simulations suggest that the entire disrupted progenitor is visible in the observed stream today, and that little further tidal debris lies beyond the ends of the stream. The luminosity, length, width, and velocity dispersion of the stream suggest a globular cluster (GC) progenitor substantially fainter and of lower surface brightness than estimated in previous work, and unlike any other known globulars in the Galaxy. This result suggests the existence of clusters that would extend the known GC population to fainter and more weakly bound systems than hitherto known. How such a weakly-bound cluster of old stars survived until it was disrupted so recently, however, remains a mystery. Integrating backwards in time, we find that the orbits of Sagittarius and Ophiuchus passed within $\sim 5$ kpc of each other about $\sim 100$ Myrs ago, an interaction that might help resolve this puzzle. Comment: 11 pages, 7 figures, submitted to MNRAS

Magnetic actuation is a droplet manipulation mechanism in digital microfluidics (DMF), where droplets can be actuated over a (super)hydrophobic surface with a magnetic force. Superparamagnetic particles or ferromagnetic liquids are added to the droplets to provide a “handle” by which the magnet can exert a force on the droplet. In this study, we present a novel method of magnetic manipulation, where droplets instead contain paramagnetic salts with molar magnetic susceptibilities (χm) approximately ≈10 000× < that for superparamagnetic particles. Droplet actuation is facilitated by low surface friction on fluorous silica nanoparticle-based superhydrophobic coatings, where <2 μN is required for reproducible droplet actuation. Different paramagnetic salts with χm from ≈4500 to 72 000 (× 10–6 cm3 mol–1) were used to make aqueous solutions of different concentration and tested for droplet actuation and sliding angle using permanent magnets (1.8–2.1 kG). Paramagnetic salts are compared in terms of solubility, m...

The evidence relating feeding and mating to hormonal control of egg production in Rhodnius prolixus is reviewed from two perspectives. It identifies crucial areas in which information is lacking, and it attempts to relate the findings, most of which have been obtained on laboratory colonies isolated for many years, to the sylvan life of the insect as an opportunistic micropredator.

Experimental and/or epidemiological studies suggest that prenatal exposure to bisphenol A (BPA) may delay fetal lung development and maturation and increase the susceptibility to childhood respiratory disease. However, the underlying mechanisms remain to be elucidated. In our previous study with cultured human fetal lung fibroblasts (HFLF), we demonstrated that 24-h exposure to 1 and 100 µM BPA increased GPR30 protein in the nuclear fraction. Exposure to 100 μM BPA had no effects on cell viability, but increased cytoplasmic expression of ERβ and release of GDF-15, as well as decreased release of IL-6, ET-1, and IP-10 through suppression of NFκB phosphorylation. By performing global gene expression and pathway analysis in this study, we identified molecular pathways, gene networks, and key molecules that were affected by 100, but not 0.01 and 1 µM BPA in HFLF. Using multiple genomic and proteomic tools, we confirmed these changes at both gene and protein levels. Our data suggest that 100 μM BPA increased CYP1B1 and HSD17B14 gene and protein expression and release of endogenous estradiol, which was associated with increased ROS production and DNA double-strand breaks, upregulation of genes and/or proteins in steroid synthesis and metabolism, and activation of Nrf2-regulated stress response pathways. In addition, BPA activated ATM-p53 signaling pathway, resulting in increased cell cycle arrest at G1 phase, senescence and autophagy, and decreased cell proliferation in HFLF. The results suggest that prenatal exposure to BPA at certain concentrations may affect fetal lung development and maturation, and thereby affecting susceptibility to childhood respiratory diseases.

Abstract Herbicide use on boreal transmission line rights-of-way has been relatively limited compared to more temperate regions and therefore challenges exist in estimating and communicating the associated risks. Herbicides directly enter the ecosystem through deposition on vegetation and soils and can be a vector of contamination to browsing herbivores. Triclopyr drift and foliage concentrations were quantified following basal bark (Garlon RTU) and low-volume foliar (Garlon XRT) field treatments to aspen (Populus tremuloides) saplings and willow (Salix bebbiana) shrubs, respectively. Greater drift concentrations localized at the stem base were observed following basal bark treatments. Conversely, concentrations in foliage following the low-volume foliar treatment (DT50 = 5.7 days and DT90 = 34.6 days) were much higher than following basal bark treatment, which also required two days to translocate into the leaves. However, dissipation was rapid from both application methods and triclopyr in foliage was less than 20 μg g−1 a year following application. A risk assessment revealed an acceptable level of risk for acute toxicity to wildlife browsing on contaminated leaves from the residues detected in this study; however, an unacceptable level of risk for chronic toxicity to long-term browsing moose. Site-specific data regarding browsing behaviour on herbicide treated rights-of-ways and species-specific reference values are needed to improve confidence in the tier-two risk assessment. Basal bark application is ideal when stem density is lower and toxic effects for herbivores is of concern and low-volume foliar applications are best suited in areas with higher stem density when off-target herbicide deposition is less acceptable.

© 2015 IEEE. We analyze postings in the Turn to Islam forum using techniques based on singular value decomposition (SVD) and the deep learning technique of stacked denoising autoencoders (SDAE). Models based on frequent words and jihadist language intensity are used, and the results compared. Our main conclusion is that SDAE approaches, while clearly discovering structure in document-word matrices, do not yet provide a natural interpretation strategy, limiting their practical usefulness. In contrast, SVD approaches provide interpretable models, primarily because of the coupling between document and word variation patterns.

AbstractMany beneficial proprieties have been associated with polyphenols from green tea, such as chemopreventive, anticarcinogenic, antiatherogenic and antioxidant actions. In this study, we investigated the effects of green tea polyphenols (GTPs) and their principal catechins on the function of P-glycoprotein (P-gp), which is involved in the multidrug resistance phenotype of cancer cells. GTPs (30 μg/ml) inhibit the photolabeling of P-gp by 75% and increase the accumulation of rhodamine-123 (R-123) 3-fold in the multidrug-resistant cell line CHRC5, indicating that GTPs interact with P-gp and inhibit its transport activity. Moreover, the modulation of P-gp transport by GTPs was a reversible process. Among the catechins present in GTPs, EGCG, ECG and CG are responsible for inhibiting P-gp. In addition, EGCG potentiates the cytotoxicity of vinblastine (VBL) in CHRC5 cells. The inhibitory effect of EGCG on P-gp was also observed in human Caco-2 cells, which form an intestinal epithelial-like monolayer. Our results indicate that, in addition to their anti-cancer properties, GTPs and more particularly EGCG inhibit the binding and efflux of drugs by P-gp. Thus, GTPs or EGCG might be potential agents for modulating the bioavailability of P-gp substrates at the intestine and the multidrug resistance phenotype associated with expression of this transporter in cancer cells.

AbstractCancer stem cells (CSCs), a rare subpopulation responsible for tumorigenesis and therapeutic resistance, are difficult to characterize and isolate. Conventional method of growing CSCs takes up to 2–8 weeks inhibiting the rate of research. Therefore, rapid reprogramming (RR) of tumor cells into CSCs is crucial to accelerate the stem cell oncology research. The current RR techniques cannot be utilized for CSC RR due to many limitations posed due to isolation requirements resulting in loss of vital data. Hence, a technique that can induce CSC RR without the need for isolation procedures is needed. Here, fabrication of a 3D‐silica nanostructured extracellular matrix for RR and in situ monitoring is reported. The RR is tested using three preclinical cancer models. The 3D matrix and a zeta potential study confirm an intense material‐cellular interaction resulting in the enhanced expressions of surface and epigenetic biomarkers. Cancer cells require only 3‐day period to form CSC spheroids with 3D‐silica extracellular matrix. Real‐time single‐cell monitoring of the methylene blue‐induced photodynamic demonstrates the dual functionality. To the authors’ knowledge, this is the first study to demonstrate a CSC epigenetic reprogramming using nanostructures. These findings may pave the path for accelerating the stem cell research in oncology.