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Aims. In this paper we report calculations for energy levels, radiative rates and excitation rates for transitions in Ni xi.
Methods. The grasp (General-purpose Relativistic Atomic Structure Package) and fac (Flexible Atomic Code) have been adopted
for calculating energy levels and radiative rates, and the Dirac Atomic R-matrix Code (darc) has been used to determine the excitation
rates.
Results. Oscillator strengths, radiative rates and line strengths are reported for all E1, E2, M1 and M2 transitions among the lowest
250 levels of Ni xi. Additionally, lifetimes are also reported for all levels. However, results for excitation rates are presented only for
transitions among the lowest 17 levels.

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OBJECTIVE: To determine the effects of maternal diabetes on fetal iron status using serum transferrin receptors (STfR) and their ratio to ferritin (TfR-F index) in cord blood. METHODS: Iron, ferritin, erythropoietin, STfR and haemoglobin concentration were measured and TfR-F index calculated in 97 maternal/cord blood pairs. Forty-nine women had type 1 diabetes (diagnosed before pregnancy) and these were compared with forty-eight non- diabetic controls. The women with type 1 diabetes were recruited consecutively from attendance at the joint antenatal endocrine clinic while the control group of women was recruited from consecutive attendance at the remaining antenatal clinics. RESULTS: The infants of the diabetic women had significantly lower levels of ferritin (47 vs 169 mug/l; p

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PURPOSE: There is now no doubt that bystander signalling from irradiated cells occurs and causes a variety of responses in cells not targeted by the ionizing track. However, the mechanisms underlying these processes are unknown and the relevance to radiotherapy and risk assessment remains controversial. Previous research by our laboratory has shown bystander effects in a human keratinocyte cell line, HPV-G cells, exposed to medium from gamma irradiated HPV-G cells. The aim of this work was to investigate if similar mechanisms to those identified in medium transfer experiments occurred in these HPV-G cells when they are in the vicinity of microbeam irradiated cells. Demonstration of a commonality of mechanisms would support the idea that the process is not artifactual. MATERIALS AND METHODS: HPV-G cells were plated as two separate populations on mylar dishes. One population was directly irradiated using a charged particle microbeam (1 - 10 protons). The other population was not irradiated. Bystander factor-induced apoptosis was investigated in both populations following treatment by monitoring the levels of reactive oxygen species and mitochondrial membrane potential using fluorescent probes. Expression of the anti-apoptotic protein, bcl-2, and cytochrome c were determined, as well as apoptosis levels. RESULTS: Microbeam irradiation induced increases in reactive oxygen species and decreases in mitochondrial membrane potential at 6 h post-exposure, increased expression of bcl-2 and cytochrome c release at 6.5 h and increased apoptosis at 24 h. CONCLUSION: This study shows that similar bystander signalling pathways leading to apoptosis are induced following microbeam irradiation and following medium transfer. This demonstrates that the mechanisms involved are common across different radiation qualities and conditions and indicates that they may be relevant in vivo.

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This paper reports the results of models of dark cloud chemistry incorporating a depth dependent density distribution with diffusive mixing and adsorption onto grains. The model is based on the approach taken by Xie et al. (1995), with the addition of grain accretion effects. Without diffusion, the central regions of the cloud freeze out in less than 10(7) years. Freeze-out time is dependent on density, so the diffuse outer region of the cloud remains abundant in gas for about an order of magnitude longer. We find that fairly small amounts of diffusive mixing can delay freeze-out at the centre of the model cloud for a time up to an order of magnitude greater than without diffusion, due to material diffusing inward from the edges of the cloud. The gas-phase lifetime of the cloud core can thus be increased by up to an order of magnitude or more by this process. We have run three different grain models with various diffusion coefficients to investigate the effects of changing the sticking parameters.

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Los primeros parágrafos de la sección “El derecho privado” (§§ 1-17) de la Doctrina del derecho de Kant incluyen el conjunto de los elementos sistemáticos que conciernen a la justificación de los derechos relativos a la propiedad. El propósito central de este trabajo es analizar la función sistemática del concepto de “posesión común originaria” en la doctrina kantiana de la propiedad, con especial interés en el sentido novedoso que adquiere ese concepto —que pertenecía a la tradición del derecho natural— en su reformulación como un “concepto práctico de la razón, que contiene a priori, el principio según el cual tan solo los hombres pueden hacer uso del lugar sobre la tierra siguiendo leyes jurídicas” (RL, 262).

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This paper reflects upon student teachers’ conceptions of inter-community relations and the preparation they receive to address issues of diversity and mutual understanding. The study in Northern Ireland is set against a backdrop of political, social and educational change, where a shared, peaceful future appears possible. Student teachers at a Catholic institution and a predominantly Protestant institution indicated a willingness to engage with issues concerning diversity and inter-community relations, despite having a limited knowledge of the concepts. However they also demonstrated clear views about the relevance and value of the preparation they received. The findings are evaluated using multicultural theory.

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The problem of diffraction of an optical wave by a 2D periodic metal aperture array with square, circular, and ring apertures is solved with allowance for the finite permittivity of a metal in the optical band. The correctness of the obtained results is verified through comparison with experimental data. It is shown that the transmission coefficient can be substantially greater than the corresponding value reached in the case of diffraction by a grating in a perfectly conducting screen.

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Studies of the female partners of politically motivated prisoners have generally studied women via a caring paradigm. Less well observed are those women who privately transgressed and challenged masculine-centred renditions or political imprisonment. This lacuna in the research dedicated to such women has been constructed around stereotypical depictions of them as a barely visible support network. We argue that the relatively indiscernible appearance of women who challenged such typecasting is attached to a persistent process of gender blindness within which women remain peripheral to wider narratives of collectivity and ideological presentation. We chart how some women actively involved themselves in creating their own identity as active agents, especially when the effects of conflict entered the private sphere.