A 43GHz VLBI mapping of SiO maser emission associated with Orion-KL IRC-2

A milliarcsecond resolution spot map of the SiO maser emission associated with IRC-2 in Orion-KL is presented. The two dominant groups of spectral features, near V(LRS) = -6 and 16 km/s, were observed in the 43 GHz, v = 1 to 0 transition of SiO, using a Mark III VLBI system. The 74 km baseline ran from Haystack Observatory in Westford, Massachusetts to Five College Radio Astronomy Observatory (FCRAO) in New Salem, Massachusetts. Five distinct maser features were observed: -8.5 to -6.5 km/s; -5 to -1.5 km/s; 12 to 13.5 km/s; 16.5 to 19 km/s; and 20 to 21 km/s (stellar velocity = 5 km/s). The relative positions were established, from an analysis of fringe phases, to an accuracy of about 5 milliarcseconds. All the features lay within an area of radius 0.08 arcseconds or 6x10(14) cm, at a distance of 500 pc. Previous interferometric studies were only able to measure the gross separation between the red and the blue shifted groups. Our measurement of the separation between these two gropus is consistent with those of the previous studies, indicating the persistence of these two centers of activity. The absolute positions of the masers with respect to IRC-2 are only known to an accuracy of about 1 arcsecond. It is assumed that IRC-2 is centered between the red shifted and the blue shifted maser features. The relative placement of these two groups of maser features agrees with observations of thermal emission from SO, which traces the outflow on a much larger scale. The SiO masers trace the neutral outflow from IRC-2 on the smallest scale yet observed

Characterisation of materials through x-ray mapping

Scanning electron microscopy (SEM) energy dispersive spectroscopy (EDS, wavelength dispersive spectroscopy (WDS) and the conbination of these techniques through x-ray mapping (XRM) have become excellent tool for characterising the distribution of elements and phases in materials. Quantitative x-ray mapping (QXRM) enables reliable quantitative results that cna be an order of magnitude better than traditional analysis and is also far superior to regions of interest x-ray maps(ROIM) where low levels of an element overlaps are present

A Hidden Broad-Line Region in the Weak Seyfert 2 Galaxy NGC 788

We have detected a broad H alpha emission line in the polarized flux spectrum of the Seyfert 2 galaxy NGC 788, indicating that it contains an obscured Seyfert 1 nucleus. While such features have been observed in ~15 other Seyfert 2s, this example is unusual because it has a higher fraction of galaxy starlight in its spectrum, a lower average measured polarization, and a significantly lower radio luminosity than other hidden Seyfert 1s discovered to date. This demonstrates that polarized broad-line regions can be detected in relatively weak classical Seyfert 2s, and illustrates why well-defined, reasonably complete spectropolarimetric surveys at H alpha are necessary in order to assess whether or not all Seyfert 2s are obscured Seyfert 1s.Comment: 10 pages using (AASTEX) aaspp4.sty and 4 postscript figures. Publications of the Astronomical Society of the Pacific, Research Notes, in pres

Estudios de acoplamiento molecular de nuevos análogos de quinolonas a la ADN girasa de Escherichia coli

Indexación: Scopus.Chemicals and CAS Registry Numbers: amino acid, 65072-01-7; ciprofloxacin, 85721-33-1; DNA topoisomerase (ATP hydrolysing); gatifloxacin, 112811-59-3, 180200-66-2; levofloxacin, 100986-85-4, 138199-71-0; lomefloxacin, 98079-51-7; moxifloxacin, 151096-09-2; nalidixic acid, 389-08-2; oxolinic acid, 14698-29-4; pipemidic acid, 51940-44-4; rufloxacin, 101363-10-4; sitafloxacin, 127254-12-0, 163253-35-8Context: Bacterial resistance to antibiotics is the inevitable consequence of the use of antimicrobial agents. Thus, quinolones are an important class of antibacterials; these agents generally consist of a 1-subtituted-1,4-dihydro-4-oxopyridine-3-carboxylic acid moiety combined with an aromatic or heteroaromatic ring fused at the 5- and 6-position. Aims: To determine the binding of quinolones to DNA gyrase of Escherichia coli. Methods: An analysis was performed using an in silico approach to determine, by docking calculations and energy descriptors, the conformer of 4‐oxo‐1,4‐dihydroquinoline skeleton that forms the most stable complex with DNA gyrase of E. coli. Results: The complex shows that the pose of the quinolones coincides with the amino acid residues Asp87, Thr88, Arg91 and Met92, which is expected to be critical in the binding of quinolones to DNA gyrase of E. coli. A series of quinolones were computationally designed, and the interactions between the quinolones and the amino acid residues of the DNA gyrase were calculated. Conclusions: Among the designed compounds, compounds 105 and 115 exhibit higher binding energy values and interact with amino acids Asp87, Thr88, Arg91 and Met92. © 2018 Journal of Pharmacy & Pharmacognosy Research.http://jppres.com/jppres/pdf/vol6/jppres18.368_6.5.386.pd

Monte Carlo modelling of Raman scattering in heterogeneous breast tissue

Breast cancer is the most common cancer for a woman to develop in her lifetime. By detecting breast cancer at an early stage, the symptoms can be easier to manage and the patient should have the best chance of survival. The current gold standard for breast cancer detection is a mammogram, followed by a biopsy and histopathology. This is effective but can also be expensive and invasive. A promising addition to the diagnostic pathway uses vibrational spectroscopy which utilises non-elastic interactions between light and tissue. Raman spectroscopy has been used widely in industry and research: it is a non-invasive and chemically specific technique. This spectroscopic technique has been proven to be applicable to the detection of microcalcifications in breast tissue to aid in diagnosing breast cancer and potentially reducing the number of biopsies required. This thesis involves the development of algorithms to model Raman scattering in biological tissues to aid in the improvement of breast cancer detection. The technique used is the numerical modelling method Monte Carlo Radiative Transport (MCRT) to effectively simulate the transport of light through turbid media. There is a need for a fast and flexible code capable of modelling a variety of Raman source materials, tissue types and shapes, input laser beams and detectors. This rapid simulation of light transport through breast tissue can provide more information and insight to complement the practical measurements and analysis of experimental work, which can be used to improve future experiments and probes. By implementing physically correct Raman scattering into a fast and powerful code, and utilising work from the field to estimate the optical properties of tissues, simulations to supplement experimental work and predict potential clinical results are performed and analysed