207 research outputs found
Glass-capillary collimator for distance compensation and partial monochromatization at rotating-anode X-ray generators
Access to the beam ports of rotating-anode X-ray generators is often obstructed by direct-coupled or belt-driven target drives. The construction of an easily adjustable stable glass-capillary collimator is described, which renders possible the unrestricted use of beam ports of these generators. Transmitted intensity and monochromaticity of the primary beam are sufficient for precession photographs of proteins after additional 20 mu m Ni filtering as demonstrated by a precession photograph of hen egg lysozyme. The straight capillary collimator is now a routinely usable low-cost device for each X-ray laboratory
Mössbauer Studies of Nickel-Iron Hydrotalcites
Hydrotalcite-like Fe-Ni-hydroxides [Ni2/3IIFe1/3III(OH)2](CO3)1/6(H2O)y , [Ni3/4IIFe1/4III(OH)2]-(CO3)1/8(H2O)y and [Ni3/4II/IIIFe1/4III(OH)2](CO3)0.14(H20)y as well as the ternary oxide NaNi2/3Fe1/3O2 have been studied by 57Fe-Mössbauer spectroscopy. All samples contain Fe3+ in a high spin state. The quadrupole interaction is smaller if a magnetic splitting is present, which may indicate a non-parallel arrangement of the principal axis of the EFG and the hyperfine field. The temperature dependence of the spectra has been understood in terms of collective cluster excitations. In this model the magnetic energy of a single domain depends on the direction of the total magnetic moment and on magnetic interaction with the neighbourhood. The spectral lineshape could be fitted assumÂing uniaxial relaxation
Modus D5.1 Definition of use cases
Within the Modus project, one of the main goals is to analyse how the performance of the overall European transport system can be optimized by considering the entire door-to-door journey holistically and considering air transport within an integrated, multimodal approach. In this regard, it is essential to identify the main barriers in achieving European (air) mobility goals and how air transport can evolve by efficiently connecting information and services with other transport modes to achieve a seamless journey experience for passengers. For this particular purposes, a set of use cases is identified and defined within this deliverable D5.1
Modus D3.1 Modal choice analysis and expert assessment
Modus Deliverable 3.1 has the objective to identify and assess (future) drivers that influence passenger demand and supply of mobility, and how these affect passenger modal choice. A comprehensive literature review is provided and identifies a set of high-level and detailed drivers of supply and demand. This analysis is complemented by an expert survey, to gain initial high-level insights regarding the potential importance of various factors, and by a multimodality workshop, to identify additional factors and acquire a first insight into potential enablers and barriers of future mobility solutions. Combining all the identified drivers reveals that most drivers are of a social, economic or technological nature. A large number of social drivers are demand drivers concerned with the passenger aspects of mobility. On the other hand, a large number of economic drivers belong to the supply drivers concerned with various cost-related factors or with transport operations, the market structure and available infrastructure
Future multimodal mobility scenarios within Europe
The European transport system faces multiple pressing challenges, including the need for significant emissions reduction in the sector and the provision of a seamless, multimodal journey to travellers. In order to address these challenges, a thorough understanding and assessment of different development pathways are required. This paper elaborates on four different scenarios developed within the scope of the Modus project. Based on these as well as additional insights from experts of the air and rail sector, initial implications for emissions reduction potential, travel times, or technological options are discussed
Phenanthroindolizidine Alkaloids Isolated from <em>Tylophora ovata</em> as Potent Inhibitors of Inflammation, Spheroid Growth, and Invasion of Triple-Negative Breast Cancer
\ua9 2022 by the authors. Triple-negative breast cancer (TNBC), representing the most aggressive form of breast cancer with currently no targeted therapy available, is characterized by an inflammatory and hypoxic tumor microenvironment. To date, a broad spectrum of anti-tumor activities has been reported for phenanthroindolizidine alkaloids (PAs), however, their mode of action in TNBC remains elusive. Thus, we investigated six naturally occurring PAs extracted from the plant Tylophora ovata: O-methyltylophorinidine (1) and its five derivatives tylophorinidine (2), tylophoridicine E (3), 2-demethoxytylophorine (4), tylophoridicine D (5), and anhydrodehydrotylophorinidine (6). In comparison to natural (1) and for more-in depth studies, we also utilized a sample of synthetic O-methyltylophorinidine (1s). Our results indicate a remarkably effective blockade of nuclear factor kappa B (NFκB) within 2 h for compounds (1) and (1s) (IC50 = 17.1 \ub1 2.0 nM and 3.3 \ub1 0.2 nM) that is different from its effect on cell viability within 24 h (IC50 = 13.6 \ub1 0.4 nM and 4.2 \ub1 1 nM). Furthermore, NFκB inhibition data for the additional five analogues indicate a structure–activity relationship (SAR). Mechanistically, NFκB is significantly blocked through the stabilization of its inhibitor protein kappa B alpha (IκBα) under normoxic as well as hypoxic conditions. To better mimic the TNBC microenvironment in vitro, we established a 3D co-culture by combining the human TNBC cell line MDA-MB-231 with primary murine cancer-associated fibroblasts (CAF) and type I collagen. Compound (1) demonstrates superiority against the therapeutic gold standard paclitaxel by diminishing spheroid growth by 40% at 100 nM. The anti-proliferative effect of (1s) is distinct from paclitaxel in that it arrests the cell cycle at the G0/G1 state, thereby mediating a time-dependent delay in cell cycle progression. Furthermore, (1s) inhibited invasion of TNBC monoculture spheroids into a matrigel\uae-based environment at 10 nM. In conclusion, PAs serve as promising agents with presumably multiple target sites to combat inflammatory and hypoxia-driven cancer, such as TNBC, with a different mode of action than the currently applied chemotherapeutic drugs
In--out intermittency in PDE and ODE models
We find concrete evidence for a recently discovered form of intermittency,
referred to as in--out intermittency, in both PDE and ODE models of mean field
dynamos. This type of intermittency (introduced in Ashwin et al 1999) occurs in
systems with invariant submanifolds and, as opposed to on--off intermittency
which can also occur in skew product systems, it requires an absence of skew
product structure. By this we mean that the dynamics on the attractor
intermittent to the invariant manifold cannot be expressed simply as the
dynamics on the invariant subspace forcing the transverse dynamics; the
transverse dynamics will alter that tangential to the invariant subspace when
one is far enough away from the invariant manifold.
Since general systems with invariant submanifolds are not likely to have skew
product structure, this type of behaviour may be of physical relevance in a
variety of dynamical settings.
The models employed here to demonstrate in--out intermittency are
axisymmetric mean--field dynamo models which are often used to study the
observed large scale magnetic variability in the Sun and solar-type stars. The
occurrence of this type of intermittency in such models may be of interest in
understanding some aspects of such variabilities.Comment: To be published in Chaos, June 2001, also available at
http://www.eurico.web.co
MoSGrid – a molecular simulation grid as a new tool in computational chemistry, biology and material science
Crystallization-induced aggregation of block copolymer micelles: influence of crystallization kinetics on morphology
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