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New Quinolones : In Vitro Effects as a Potential Source of Clinical Toxicity

4-Quinolones affect mammalian cellular functions in vitro in several ways. High concentrations inhibit DNA replication, but individual genes are perhaps sensitive to lower concentrations of drug. Inhibition of cell proliferation differs widely among 4-quinolones. Ciprofloxacin and norfloxacin are the most antiproliferative, inhibiting cell growth by -30% at 20 mg/L. Genotoxicity tests with 4-quino

Landcover change detection using PSO-evaluated quantum CA approach on multi-temporal remote-sensing watershed images

Computer science plays a major role in image segmentation and image processing applications. Despite the computational cost, PSO evaluated QCA approaches perform comparable to or better than their crisp counterparts. This novel approach, proposed in this chapter, has been found to enhance the functionality of the CA rule base and thus enhance the established potentiality of the fuzzy-based segment

Peer engagement for teaching and learning: competence, autonomy and social solidarity in academic microcultures

University teachers’ engagement in teaching is a crucial aspect for the quality of student learning. In this article, we explore where such engagement comes from. We use a sociocultural perspective to investigate how teachers’ colleagues and leaders, in what we call academic microcultures, influence such engagement. A microculture can be a working group such as a teaching team, an educational progUniversity teachers’ engagement in teaching is a crucial aspect for the quality of student learning. In this article, we explore where such engagement comes from. We use a sociocultural perspective to investigate how teachers’ colleagues and leaders, in what we call academic microcultures, influence such engagement. A microculture can be a working group such as a teaching team, an educational prog

Geophysical surveys for improving the hydrogeological conceptual models in the semi-arid region of Valle Alto (Bolivia)

Geophysical methods provide important information for mapping the subsurface. In semiarid areas, a detailed knowledge of the aquifers geometry can assist to a better management of groundwater. In the Valle Alto (Bolivia), which is a semiarid region, there is gap in the knowledge about the aquifer system geometry and hydrogeological processes. Local reports indicated problems in some wells such as

Controlled Surface Silanization for Actin-Myosin Based Nanodevices and Biocompatibility of New Polymer Resists

Molecular motor-based nanodevices require organized cytoskeletal filament guiding along motility-promoting tracks, confined by motility-inhibiting walls. One way to enhance motility quality on the tracks, particularly in terms of filament velocity but also the fraction of motile filaments, is to optimize the surface hydrophobicity. We have investigated the potential to achieve this for the actin-m

Shortcuts for the circle

Let C be the unit circle in R2. We can view C as a plane graph whose vertices are all the points on C, and the distance between any two points on C is the length of the smaller arc between them. We consider a graph augmentation problem on C, where we want to place k⩾1 shortcuts on C such that the diameter of the resulting graph is minimized. We analyze for each k with 1⩽k⩽7 what the optimal set of

To what extent does the zintl-klemm formalism work? The Eu(Zn 1 - X Ge X ) 2 series

The series of ternary polar intermetalllcs Eu(Zn 1-x Ge x ) 2 0≤x≤ 1) has been investigated and characterized by powder and single-crystal X-ray diffraction as well as physical property measurements. For 0.50(2) 0.75, respectively, orthorhombic KHg 2 -type and trigonal EuGe 2 -type phases occur as a second phase in mixtures with an AIB 2 -type phase. Diffraction of the x= 0.75(2) sample sh

Incommensurate stistaite - Order made to order

The structure of stistaite -SbSn, was investigated by single crystal X-ray diffraction and EDX to yield a simple relation between the modulated structure and the composition. Stistaite is found to be ineommensurately ordered over the entire stability region.

Structural study of the disordered RECd6 quasicrystal approximants (RE = Tb, Ho, Er, Tm and Lu)

The crystal structures of approximants RECd6 (RE = Tb, Ho, Er, Tm and Lu) have been refined from single crystal X-ray diffraction data. This work is a continuation of a previous study of MCdg approximants [1] in which the different types of disorder of the central Cd4 tetrahedra located in the dodecahedral cavities were examined. The structures of the title compounds are all similar to GdCd6 and d

The structure of onoratoite, Sb8 O11 X2 (X = Cl, Br) revisited

The crystal structure of Sb8O11Cl2 (onoratoite) is redetermined in the triclinic space group P-1. The crystal structure was previously described by a partially disordered model in the monoclinic space group C 2 / m containing some partially occupied oxygen atoms. The new structural model features exclusively atomic positions that are fully occupied. The crystal structure was solved from single cry

Highly hydrated cations : Deficiency, mobility, and coordination of water in crystalline nonahydrated scandium(III), yttrium(III), and lanthanoid(III) trifluoromethanesulfonates

Trivalent lanthanide-like metal ions coordinate nine water oxygen atoms, which form a tricapped trigonal prism in a large number of crystalline hydrates. Water deficiency, randomly distributed over the capping positions, was found for the smallest metal ions in the isomorphous nonahydrated trifluoromethanesulfonates, [M-(H2O)n](CF 3SO3)3, in which M = ScIII, Lu III, YbIII, TmIII or ErIII. The hydr

Phase stability in the systems AeAl2-xMgx (Ae = Ca, Sr, Ba) : Electron concentration and size controlled variations on the laves phase structural theme

The systems AeAl2-xMgx (Ae = Ca, Sr, Ba) display electron concentration induced Laves phase structural changes. However, the complete sequence MgCu2 → MgNi2 → MgZn 2 with increasing x (decreasing electron count) is only observed for Ae = Ca. Compounds SrAl2-xMgx (0 < x ≤ 2) and BaAl2-xMgx (x = 0.85 and 2.0) were synthesized and structurally characterized by X-ray diffraction experiments. For the S

The incommensurably modulated structure of ζ-Zn3-xSb 2

The incommensurately modulated structure of ζ-Zn3-xSb 2 was solved and refined versus X-ray single crystal diffraction data using a 3+1 dimensional superspace formalism. The compound crystallizes in the orthorhombic system in the 3+1 dimensional superspace group Pnna(α0)0s0 with the cell parameters a=7.283(3)Å, b=15.398(5)Å, c=25.06(1)Å, q=(α,0,0), α≈0.385. The structure features columns of interg