Stripe-like nanoscale structural phase separation in superconducting BaPb(1-x)Bi(x)O3.

The phase diagram of BaPb(1-x)Bi(x)O3 exhibits a superconducting dome in the proximity of a charge density wave phase. For the superconducting compositions, the material coexists as two structural polymorphs. Here we show, via high-resolution transmission electron microscopy, that the structural dimorphism is accommodated in the form of partially disordered nanoscale stripes. Identification of the morphology of the nanoscale structural phase separation enables determination of the associated length scales, which we compare with the Ginzburg-Landau coherence length. We find that the maximum Tc occurs when the superconducting coherence length matches the width of the partially disordered stripes, implying a connection between the structural phase separation and the shape of the superconducting dome.

Detection and cloaking of molecular objects in coherent nanostructures using inelastic electron tunneling spectroscopy.

We address quantum invisibility in the context of electronics in nanoscale quantum structures. We make use of the freedom of design that quantum corrals provide and show that quantum mechanical objects can be hidden inside the corral, with respect to inelastic electron scattering spectroscopy in combination with scanning tunneling microscopy, and we propose a design strategy. A simple illustration of the invisibility is given in terms of an elliptic quantum corral containing a molecule, with a local vibrational mode, at one of the foci. Our work has implications to quantum information technology and presents new tools for nonlocal quantum detection and distinguishing between different molecules.

Information transport and computation in nanometre-scale structures.

We discuss two examples of novel information-transport and processing mechanisms in nanometre-scale structures. The local modulation and detection of a quantum state can be used for information transport at the nanometre length-scale, an effect we call a 'quantum mirage'. We demonstrate that, unlike conventional electronic information transport using wires, the quantum mirage can be used to pass multiple channels of information through the same volume of a solid. We discuss a new class of nanometre-scale structures called 'molecule cascades', and show how they may be used to implement a general-purpose binary-logic computer in which all of the circuitry is at the nanometre length-scale.

Issues in adolescent health: a challenge for nursing.

The young people of today are the greatest investment we as adults have in our future. The care and nurturing we afford the adolescent is just as important as that which we afford to children or the elderly. Although most adolescents have a preoccupation with their bodies, they do not always engage in activities that will protect and develop them. Adolescents are often exposed to peer pressure, the effects of which may impact negatively on their behaviour and their health. Many adolescent health and behavioural issues evolve from developmental changes and can manifest in a confrontational attitude toward society, parents and others. They are hormonally 'fully charged', and their adolescent sexuality can have enormous effects on their future physical, psychosocial, moral and sexual development. Nurses have a pivotal role to play in ensuring children and adolescents learn the facts relating to the consequences of engaging in unhealthy behaviour and lifestyle. Nurses must also encourage parents to model and reinforce good health practices, such as serving balanced and nutritious meals at regular times and planning positive family activities. In this paper we review some of the salient issues in adolescent health today.

Scattering theory of Kondo mirages and observation of single Kondo atom phase shift.

We explain the origin of the Kondo mirage seen in recent quantum corral scanning tunneling microscope experiments with a scattering theory of electrons on the surfaces of metals. Our theory, combined with experimental data, provides a direct observation of a single Kondo atom phase shift. The Kondo mirage observed at the empty focus of an elliptical quantum corral is shown to arise from multiple electron bounces off the corral wall adatoms. We demonstrate our theory with direct quantitive comparison to experimental data.

High-level production and purification of biologically active proteins from bacterial and mammalian cells using the tandem pGFLEX expression system.

Because of the complexities involved in the regulation of gene expression in Escherichia coli and mammalian cells, it is considered general practice to use different vectors for heterologous expression of recombinant proteins in these host systems. However, we have developed and report a shuttle vector system, pGFLEX, that provides high-level expression of recombinant glutathione S-transferase (GST) fusion proteins in E. coli and mammalian cells. pGFLEX contains the cytomegaloma virus (CMV) immediate-early promoter in tandem with the E. coli lacZpo system. The sequences involved in gene expression have been appropriately modified to enable high-level production of fusion proteins in either cell type. The pGFLEX expression system allows production of target proteins fused to either the N or C terminus of the GST pi protein and provides rapid purification of target proteins as either GST fusions or native proteins after cleavage with thrombin. The utility of this vector in identifying and purifying a component of a multi-protein complex is demonstrated with cyclin A. The pGFLEX expression system provides a singular and widely applicable tool for laboratory or industrial production of biologically active recombinant proteins in E. coli and mammalian cells.

Mapping of the loci involved in the catabolic oxidation of L-hydroxyproline in Pseudomonas aeruginosa PAO.

Genes specifying the oxidative utilization of hydroxyproline (Hyp) in P. aeruginosa PAO were located on the chromosome, around 19th minute by conjugation experiments. A map order of his-68-his-07-Hyp was assigned. Confirmation of this gene order was also demonstrated by transductional mapping studies. All the genes determining the enzymes of Hyp dissimiliatory pathway were closely linked.