Isotope effect on the transition temperature TcT_c in Fe-based superconductors: the current status

The results of the Fe isotope effect (Fe-IE) on the transition temperature $T_c$ obtained up to date in various Fe-based high temperature superconductors are summarized and reanalyzed by following the approach developed in [Phys. Rev. B 82, 212505 (2010)]. It is demonstrated that the very controversial results for Fe-IE on $T_c$ are caused by small structural changes occurring simultaneously with the Fe isotope exchange. The Fe-IE exponent on $T_c$ [$\alpha_{\rm Fe}=-(\Delta T_c/T_c)/(\Delta M/M)$, $M$ is the isotope mass] needs to be decomposed into two components with the one related to the structural changes ($\alpha_{\rm Fe}^{\rm str}$) and the genuine (intrinsic) one ($\alpha_{\rm Fe}^{\rm int}$). The validity of such decomposition is further confirmed by the fact that $\alpha_{\rm Fe}^{\rm int}$ coincides with the Fe-IE exponent on the characteristic phonon frequencies $\alpha_{\rm Fe}^{\rm ph}$ as is reported in recent EXAFS and Raman experiments.Comment: 7 pages, 4 figures. The paper is partially based on the results published in [New J. Phys. 12, 073024 (2010) = arXiv:1002.2510] and [Phys. Rev. B 82, 212505 (2010) = arXiv:1008.4540

Chronic kidney disease after liver, cardiac, lung, heart–lung, and hematopoietic stem cell transplant

Patient survival after cardiac, liver, and hematopoietic stem cell transplant (HSCT) is improving; however, this survival is limited by substantial pretransplant and treatment-related toxicities. A major cause of morbidity and mortality after transplant is chronic kidney disease (CKD). Although the majority of CKD after transplant is attributed to the use of calcineurin inhibitors, various other conditions such as thrombotic microangiopathy, nephrotic syndrome, and focal segmental glomerulosclerosis have been described. Though the immunosuppression used for each of the transplant types, cardiac, liver and HSCT is similar, the risk factors for developing CKD and the CKD severity described in patients after transplant vary. As the indications for transplant and the long-term survival improves for these children, so will the burden of CKD. Nephrologists should be involved early in the pretransplant workup of these patients. Transplant physicians and nephrologists will need to work together to identify those patients at risk of developing CKD early to prevent its development and progression to end-stage renal disease

A Fermi Liquid Electronic Structure and the Nature of the Carriers in High-Tc Cuprates: A Photoemission Study

We have performed angle-integrated and angle-resolved photoemission measurements at 20 K on well-characterized single crystals of high Tc cuprates (both 1:2:3-type and 2:2:1:2-type) cleaved in situ, and find a relatively large, resolution limited Fermi edge which shows large amplitude variations with photon energy, indicative of band structure final state effects. The lineshape of the spectra of the 1:2:3 materials as a function of photon energy are well reproduced by band structure predictions, indicating a correct mix of 2p and 3d orbitals in the calculations, while the energy positions of the peaks agree with calculated bands to within approx;;0.5 eV. This may yet prove to reflect the effects of Coulomb correlation. We nevertheless conclude that a Fermi liquid approach to conductivity is appropriate. Angle-resolved data, while still incomplete, suggest agreement with the Fermi surface predicted by the LDA calculations. A BCS-like energy gap is observed in the 2:2:1:2 materials, whose magnitude is twice the weak coupling BCS value (i.e., 2Δ approx;; 7kTc). © 1990 IOP Publishing Ltd

The effectiveness of video interaction guidance in parents of premature infants: A multicenter randomised controlled trial

<p>Abstract</p> <p>Background</p> <p>Studies have consistently found a high incidence of neonatal medical problems, premature births and low birth weights in abused and neglected children. One of the explanations proposed for the relation between neonatal problems and adverse parenting is a possible delay or disturbance in the bonding process between the parent and infant. This hypothesis suggests that due to neonatal problems, the development of an affectionate bond between the parent and the infant is impeded. The disruption of an optimal parent-infant bond -on its turn- may predispose to distorted parent-infant interactions and thus facilitate abusive or neglectful behaviours. Video Interaction Guidance (VIG) is expected to promote the bond between parents and newborns and is expected to diminish non-optimal parenting behaviour.</p> <p>Methods/design</p> <p>This study is a multi-center randomised controlled trial to evaluate the effectiveness of Video Interaction Guidance in parents of premature infants. In this study 210 newborn infants with their parents will be included: n = 70 healthy term infants (>37 weeks GA), n = 70 moderate term infants (32–37 weeks GA) which are recruited from maternity wards of 6 general hospitals and n = 70 extremely preterm infants or very low birth weight infants (<32 weeks GA) recruited by the NICU of 2 specialized hospitals. The participating families will be divided into 3 groups: a reference group (<it>i.e.</it> full term infants and their parents, receiving care as usual), a control group (<it>i.e.</it> premature infants and their parents, receiving care as usual) and an intervention group (<it>i.e.</it> premature infants and their parents, receiving VIG). The data will be collected during the first six months after birth using observations of parent-infant interactions, questionnaires and semi-structured interviews. Primary outcomes are the quality of parental bonding and parent-infant interactive behaviour. Parental secondary outcomes are (posttraumatic) stress symptoms, depression, anxiety and feelings of anger and hostility. Infant secondary outcomes are behavioral aspects such as crying, eating, and sleeping.</p> <p>Discussion</p> <p>This is the first prospective study to empirically evaluate the effect of VIG in parents of premature infants. Family recruitment is expected to be completed in January 2012. First results should be available by 2012.</p> <p>Trail registration number</p> <p>NTR3423</p