830 research outputs found

    Measuring a New Stress Domain: Validation of the Couple-Level Minority Stress Scale

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    Existing social stress frameworks largely conceive of stress as emanating from individual experience. Recent theory and research concerning minority stress have focused on same-sex couples' experiences of both eventful and chronic stressors associated with being in a stigmatized relationship, including having ongoing or episodic fears of discrimination, and experiencing actual acts of discrimination. Such couple-level minority stressors represent a novel domain of social stress affecting minority populations that is only beginning to become a focus in empirical investigations testing minority stress theory. This article presents the results of psychometric analyses of dyadic data from 106 same-sex couples from across the U.S., introducing the Couple-Level Minority Stress (CLMS) scale featuring eight new couple-level minority stress factors: (1) Couple-Level Stigma; (2) Couple-Level Discrimination; (3) Seeking Safety as a Couple; (4) Perceived Unequal Relationship Recognition; (5) Couple-Level Visibility; (6) Managing Stereotypes about Same-Sex Couples; (7) Lack of Integration with Families of Origin; and (8) Lack of Social Support for Couples. The CLMS demonstrated a clear factor structure with satisfactory model-data fit and subscale reliabilities. The CLMS also exhibited validity as a correlate of one indicator of relationship quality (relationship satisfaction) and three indicators of mental health (nonspecific psychological distress, depressive symptomatology, and problematic drinking) when controlling for individual-level minority stressors and has great potential to extend and enrich minority stress research, particularly studies that deepen understandings of longstanding health inequities based on sexual orientation

    Hypervitaminosis A is prevalent in children with CKD and contributes to hypercalcemia.

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    Vitamin A accumulates in renal failure, but the prevalence of hypervitaminosis A in children with predialysis chronic kidney disease (CKD) is not known. Hypervitaminosis A has been associated with hypercalcemia. In this study we compared dietary vitamin A intake with serum retinoid levels and their associations with hypercalcemia

    Spectroscopy of free radicals and radical containing entrance-channel complexes in superfluid helium nano-droplets

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    The spectroscopy of free radicals and radical containing entrance-channel complexes embedded in superfluid helium nano-droplets is reviewed. The collection of dopants inside individual droplets in the beam represents a micro-canonical ensemble, and as such each droplet may be considered an isolated cryo-reactor. The unique properties of the droplets, namely their low temperature (0.4 K) and fast cooling rates (1016\sim10^{16} K s1^{-1}) provides novel opportunities for the formation and high-resolution studies of molecular complexes containing one or more free radicals. The production methods of radicals are discussed in light of their applicability for embedding the radicals in helium droplets. The spectroscopic studies performed to date on molecular radicals and on entrance / exit-channel complexes of radicals with stable molecules are detailed. The observed complexes provide new information on the potential energy surfaces of several fundamental chemical reactions and on the intermolecular interactions present in open-shell systems. Prospects of further experiments of radicals embedded in helium droplets are discussed, especially the possibilities to prepare and study high-energy structures and their controlled manipulation, as well as the possibility of fundamental physics experiments.Comment: 25 pages, 12 figures, 4 tables (RevTeX

    A bayesian meta-analysis of multiple treatment comparisons of systemic regimens for advanced pancreatic cancer

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    © 2014 Chan et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Background: For advanced pancreatic cancer, many regimens have been compared with gemcitabine (G) as the standard arm in randomized controlled trials. Few regimens have been directly compared with each other in randomized controlled trials and the relative efficacy and safety among them remains unclear

    Exploring hypotheses of the actions of TGF-beta 1 in epidermal wound healing using a 3D computational multiscale model of the human epidermis

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    In vivo and in vitro studies give a paradoxical picture of the actions of the key regulatory factor TGF-beta 1 in epidermal wound healing with it stimulating migration of keratinocytes but also inhibiting their proliferation. To try to reconcile these into an easily visualized 3D model of wound healing amenable for experimentation by cell biologists, a multiscale model of the formation of a 3D skin epithelium was established with TGF-beta 1 literature-derived rule sets and equations embedded within it. At the cellular level, an agent-based bottom-up model that focuses on individual interacting units ( keratinocytes) was used. This was based on literature-derived rules governing keratinocyte behavior and keratinocyte/ECM interactions. The selection of these rule sets is described in detail in this paper. The agent-based model was then linked with a subcellular model of TGF-beta 1 production and its action on keratinocytes simulated with a complex pathway simulator. This multiscale model can be run at a cellular level only or at a combined cellular/subcellular level. It was then initially challenged ( by wounding) to investigate the behavior of keratinocytes in wound healing at the cellular level. To investigate the possible actions of TGF-beta 1, several hypotheses were then explored by deliberately manipulating some of these rule sets at subcellular levels. This exercise readily eliminated some hypotheses and identified a sequence of spatial-temporal actions of TGF-beta 1 for normal successful wound healing in an easy-to-follow 3D model. We suggest this multiscale model offers a valuable, easy-to-visualize aid to our understanding of the actions of this key regulator in wound healing, and provides a model that can now be used to explore pathologies of wound healing

    Density functional theory studies of MTSL nitroxide side chain conformations attached to an activation loop

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    A quantum-mechanical (QM) method rooted on density functional theory (DFT) linked to the Stochastic Liouville equation (SLE) in the Fokker Planck (FP) form has been employed for the first time to sample the methane-thiosulfonate spin label (MTSL) conformational space attached to the Aurora-A kinase activation loop and to calculate the EPR spectrum. The features of the calculated energy surface allowed us to describe the system in a limited number of rotamers stabilized by interactions of the MTSL side chain and neighbouring residues. The relevant magnetic parameters and the electron paramagnetic resonance (EPR) spectrum were subsequently calculated from the trajectories of the spin probe in the protein environment. The comparison between theoretical and experimental continuous wave (CW) EPR spectra revealed some small differences in the EPR line shape which arises from the combinations of g- and A-values obtained from the conformations selected. The theoretical approach adopted in this work can be used to recognise the contribution of MTSL rotamers to the EPR spectrum in order to help extract structural/dynamics properties of protein from the experimental data

    The solid-state photo-CIDNP effect

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    The solid-state photo-CIDNP effect is the occurrence of a non-Boltzmann nuclear spin polarization in rigid samples upon illumination. For solid-state NMR, which can detect this enhanced nuclear polarization as a strong modification of signal intensity, the effect allows for new classes of experiments. Currently, the photo- and spin-chemical machinery of various RCs is studied by photo-CIDNP MAS NMR in detail. Until now, the effect has only been observed at high magnetic fields with 13C and 15N MAS NMR and in natural photosynthetic RC preparations in which blocking of the acceptor leads to cyclic electron transfer. In terms of irreversible thermodynamics, the high-order spin structure of the initial radical pair can be considered as a transient order phenomenon emerging under non-equilibrium conditions and as a first manifestation of order in the photosynthetic process. The solid-state photo-CIDNP effect appears to be an intrinsic property of natural RCs. The conditions of its occurrence seem to be conserved in evolution. The effect may be based on the same fundamental principles as the highly optimized electron transfer. Hence, the effect may allow for guiding artificial photosynthesis
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