Background Debate continues among nurses about the advantages and disadvantages of family presence during resuscitation. Knowledge development about such family presence is constrained by the lack of reliable and valid instruments to measure key variables. Objectives To test 2 instruments used to measure nurses’ perceptions of family presence during resuscitation, to explore demographic variables and perceptions of nurses’ self-confidence and the risks and benefits related to such family presence in a broad sample of nurses from multiple hospital units, and to examine differences in perceptions of nurses who have and who have not invited family presence. Methods Nurses (n = 375) completed the Family Presence Risk-Benefit Scale and the Family Presence Self-confidence Scale. Results Nurses’ perceptions of benefits, risks, and self-confidence were significantly and strongly interrelated. Nurses who invited family presence during resuscitation were significantly more self-confident in managing it and perceived more benefits and fewer risks (P < .001). Perceptions of more benefits and fewer risks were related to membership in professional organizations, professional certification, and working in an emergency department (P < .001). Data supported initial reliability and construct validity for the 2 scales. Conclusions Nurses’ perceptions of the risks and benefits of family presence during resuscitation vary widely and are associated with how often the nurses invite family presence. After further testing, the 2 new scales may be suitable for measuring interventional outcomes, serve as self-assessment tools, and add to conceptual knowledge about family presence.

A novel interplay between d-wave superconducting order parameter symmetry and the underlying Cu 3d orbital based electronic structure of copper oxides leads to a striking anisotropy in the superfluid response of these systems. In clean tetragonal materials the c axis penetration depth increases as T 5 at low temperature, in contrast to linear T behavior in the ab plane. Disorder is a relevant perturbation which causes all components of the superfluid response to depend quadratically on temperature at low temperature. However, the crossover temperature scale from the intrinsic d-wave behavior to the disorder dominated behavior for the in-plane response may be different from that for the out-plane response.[S0031-9007 (96)01768-1] PACS numbers: 74.25.Nf, 74.20.MnA variety of experimental data on copper oxide superconductors are compatible with a pairing state of d x 2 2y 2 symmetry in CuO 2 planes. The existence of energy gap nodes in this state has profound consequences for the low temperature electromagnetic response. The in-plane penetration depth increases linearly with T at low T in contrast to the activated behavior of conventional superconductors. The linear-T result holds in the regime where the response is governed by coherently propagating fermion quasiparticle excitations, i.e., at temperatures G ø T ø T c where G is the superconducting quasiparticle scattering rate. Linear-T behavior in the ab plane has now been established in both chain and nonchain copper oxides [1][2][3][4]. The c-axis penetration depth l c ͑T ͒ in La 22x Sr x CuO 4 [5], YBa 2 Cu 3 O 72d [1], Bi 2 Sr 2 CaCu 2 O 81x [2,6], and HgBa 2 Ca 2 Cu 3 O 81x [4] has now been measured. However, as it is very difficult to determine accurately the low T dependence of l c due to the high anisotropy of high-T c oxides, the published data of l c still lack consistency except all have shown that the T dependence of l c is much weaker than that observed in the ab plane. In La 22x Sr x CuO 4 , l c ͑T͒ drops exponentially with T at low temperature; while in other compounds, l c ͑T͒ approaches its zero temperature value in a power law. Straightforward extension of the d-wave model to 3D leads to line gap nodes on a warped cylindrical Fermi surface. This gives a linear-T c-axis response in apparent contradiction to experiment [7].In this paper we propose that weak T dependence of the c-axis superfluid density r c s is a general feature of nonchain cuprates with crystal tetragonal symmetry, whose origin lies in the simple but unusual electronic structure of these materials. Our analysis is based on the assumption that coherent Bloch bands along the c axis are present at low temperatures; i.e., k z is a good quantum number. As discussed below, an essential feature of the electronic structure is that the c-axis hopping integral t Ќ ͑k k ͒ is a function of the in-plane momentum k k and is vanishingly small when k k lies along the zone diagonals of the 2D Brillouin zone [8,9]. The nodal lines of the d x 2 2y 2 -wave gap D͑k k ͒ D͑cos k x 2 cos k y ͒ and the ze...

A numerical approach to disordered 2D superconductors described by BCS mean field theory is outlined. The energy gap and the superfluid density at zero temperature and the quasiparticle density of states are studied.The method involves approximate self-consistent solutions of the Bogolubovde Gennes equations on finite square lattices. Where comparison is possible, the results of standard analytic approaches to this problem are reproduced.Detailed modeling of impurity effects is practical using this approach. The range of the impurity potential is shown to be of quantitative importance in the case of strong potential scatterers. We discuss the implications for experiments, such as the rapid suppression of superconductivity by Zn doping in Copper-Oxide superconductors.

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