The impact of nurse leadership education on clinical practice: An integrative review.

AIM: The aim of this paper is to critically evaluate the literature investigating the impact of nurse leadership education on clinical practice. BACKGROUND: Effective leadership is vital for high-quality patient care. Leadership education is designed to support nurses to develop the appropriate skills and behaviors to become clinical leaders. However, to date, the impact of such education on subsequent clinical practice is unclear. EVALUATION: An integrative review was conducted. Ten papers were included related to the experiences of nurses undertaking leadership education. KEY ISSUE: Analysis of the included papers indicated that leadership education contributed to improving clinical practice in two ways. These two key themes were; impact on the individual and impact on others. CONCLUSION: While there is a plethora of literature reviewing nurse leadership and clinical practice, there is a gap in understanding how nurse leadership education can contribute to changed practice. IMPLICATIONS FOR NURSING MANAGEMENT: Nurse managers can use this information to guide future leadership education programs to ensure that they promote positive work environments and high-quality care that improves clinical outcomes.

Nanoscale Surface Charge Visualization of Human Hair.

The surface charge and topography of human hair are visualized synchronously at the nanoscale using scanning ion conductance microscopy (SICM), a scanning nanopipette probe technique that uses local ion conductance currents to image the physicochemical properties of interfaces. By combining SICM data with finite element method (FEM) simulations that solve for ion transport at the nanopipette under bias, one is able to quantitatively correlate colocated surface charge and topography. The hair samples studied herein, from a 25-year-old Caucasian male with light hair (as an exemplar), reveal that untreated hair, in areas ca. 1 cm from the root, has a fairly uniform negative charge density of ca. -15 mC/cm-2 (in pH 6.8 aqueous solution), with some higher magnitude negative values localized near the boundaries between hair cuticles. Common chemical treatments result in varying degrees of charge heterogeneity. A bleach treatment produces some highly negatively charged localized regions (-80 to -100 mC/cm-2 at pH 6.8), due to hair damage, while a chemical conditioner treatment causes an overall increase in the homogeneity of the surface charge, together with a shift in the surface charge to positive values. Bleached surfaces are temporarily repaired to some extent through the use of a conditioner, as judged by the surface charge values. Finally, SICM is able to detect differences in the surface charge density of hair at different distances from the root (equivalent to hair age). Presently, the assessment of hair surface charge mainly relies on zeta-potential measurements which lack spatial resolution, among other drawbacks. In contrast, SICM enables quantitative surface charge mapping that should be beneficial in deepening understanding of the physicochemical properties of hair and lead to the rational development of new treatments and the assessment of their efficacy at the nanoscale. Given the widespread interest in the surface charge properties of interfaces, this work further demonstrates that SICM should generally become an important characterization tool for surface analytical chemists.

Scanning Ion Conductance Microscopy: Quantitative Nanopipette Delivery-Substrate Electrode Collection Measurements and Mapping.

Scanning ion conductance microscopy (SICM) is becoming a powerful multifunctional tool for probing and analyzing surfaces and interfaces. This work outlines methodology for the quantitative controlled delivery of ionic redox-active molecules from a nanopipette to a substrate electrode, with a high degree of spatial and temporal precision. Through control of the SICM bias applied between a quasi-reference counter electrode (QRCE) in the SICM nanopipette probe and a similar electrode in bulk solution, it is shown that ionic redox species can be held inside the nanopipette, and then pulse-delivered to a defined region of a substrate positioned beneath the nanopipette. A self-referencing hopping mode imaging protocol is implemented, where reagent is released in bulk solution (reference measurement) and near the substrate surface at each pixel in an image, with the tip and substrate currents measured throughout. Analysis of the tip and substrate current data provides an improved understanding of mass transport and nanoscale delivery in SICM and a new means of synchronously mapping electrode reactivity, surface topography, and charge. Experiments on Ru(NH3)63+ reduction to Ru(NH3)62+ and dopamine oxidation in aqueous solution at a carbon fiber ultramicroelectrode (UME), used as the substrate, illustrate these aspects. Finite element method (FEM) modeling provides quantitative understanding of molecular delivery in SICM. The approach outlined constitutes a new methodology for electrode mapping and provides improved insights on the use of SICM for controlled delivery to interfaces generally.

Differential-Concentration Scanning Ion Conductance Microscopy.

Scanning ion conductance microscopy (SICM) is a nanopipette-based scanning probe microscopy technique that utilizes the ionic current flowing between an electrode inserted inside a nanopipette probe containing electrolyte solution and a second electrode placed in a bulk electrolyte bath, to provide information on a substrate of interest. For most applications to date, the composition and concentration of the electrolyte inside and outside the nanopipette is identical, but it is shown herein that it can be very beneficial to lift this restriction. In particular, an ionic concentration gradient at the end of the nanopipette, generates an ionic current with a greatly reduced electric field strength, with particular benefits for live cell imaging. This differential concentration mode of SICM (ΔC-SICM) also enhances surface charge measurements and provides a new way to carry out reaction mapping measurements at surfaces using the tip for simultaneous delivery and sensing of the reaction rate. Comprehensive finite element method (FEM) modeling has been undertaken to enhance understanding of SICM as an electrochemical cell and to enable the interpretation and optimization of experiments. It is shown that electroosmotic flow (EOF) has much more influence on the nanopipette response in the ΔC-SICM configuration compared to standard SICM modes. The general model presented advances previous treatments, and it provides a framework for quantitative SICM studies.

Simultaneous Topography and Reaction Flux Mapping at and around Electrocatalytic Nanoparticles.

The characterization of electrocatalytic reactions at individual nanoparticles (NPs) is presently of considerable interest but very challenging. Herein, we demonstrate how simple-to-fabricate nanopipette probes with diameters of approximately 30 nm can be deployed in a scanning ion conductance microscopy (SICM) platform to simultaneously visualize electrochemical reactivity and topography with high spatial resolution at electrochemical interfaces. By employing a self-referencing hopping mode protocol, whereby the probe is brought from bulk solution to the near-surface at each pixel, and with potential-time control applied at the substrate, current measurements at the nanopipette can be made with high precision and resolution (30 nm resolution, 2600 pixels µm-2, <0.3 s pixel-1) to reveal a wealth of information on the substrate physicochemical properties. This methodology has been applied to image the electrocatalytic oxidation of borohydride at ensembles of AuNPs on a carbon fiber support in alkaline media, whereby the depletion of hydroxide ions and release of water during the reaction results in a detectable change in the ionic composition around the NPs. Through the use of finite element method simulations, these observations are validated and analyzed to reveal important information on heterogeneities in ion flux between the top of a NP and the gap at the NP-support contact, diffusional overlap and competition for reactant between neighboring NPs, and differences in NP activity. These studies highlight key issues that influence the behavior of NP assemblies at the single NP level and provide a platform for the use of SICM as an important tool for electrocatalysis studies.

Multifunctional scanning ion conductance microscopy.

Scanning ion conductance microscopy (SICM) is a nanopipette-based technique that has traditionally been used to image topography or to deliver species to an interface, particularly in a biological setting. This article highlights the recent blossoming of SICM into a technique with a much greater diversity of applications and capability that can be used either standalone, with advanced control (potential-time) functions, or in tandem with other methods. SICM can be used to elucidate functional information about interfaces, such as surface charge density or electrochemical activity (ion fluxes). Using a multi-barrel probe format, SICM-related techniques can be employed to deposit nanoscale three-dimensional structures and further functionality is realized when SICM is combined with scanning electrochemical microscopy (SECM), with simultaneous measurements from a single probe opening up considerable prospects for multifunctional imaging. SICM studies are greatly enhanced by finite-element method modelling for quantitative treatment of issues such as resolution, surface charge and (tip) geometry effects. SICM is particularly applicable to the study of living systems, notably single cells, although applications extend to materials characterization and to new methods of printing and nanofabrication. A more thorough understanding of the electrochemical principles and properties of SICM provides a foundation for significant applications of SICM in electrochemistry and interfacial science.

Quantitative Visualization of Molecular Delivery and Uptake at Living Cells with Self-Referencing Scanning Ion Conductance Microscopy-Scanning Electrochemical Microscopy.

A multifunctional dual-channel scanning probe nanopipet that enables simultaneous scanning ion conductance microscopy (SICM) and scanning electrochemical microscopy (SECM) measurements is demonstrated to have powerful new capabilities for spatially mapping the uptake of molecules of interest at living cells. One barrel of the probe is filled with electrolyte and the molecules of interest and is open to the bulk solution for both topographical feedback and local delivery to a target interface, while a solid carbon electrode in the other barrel measures the local concentration and flux of the delivered molecules. This setup allows differentiation in molecular uptake rate across several regions of single cells with individual measurements at nanoscale resolution. Further, operating in a "hopping mode", where the probe is translated toward the interface (cell) at each point allows self-referencing to be employed, in which the carbon electrode response is calibrated at each and every pixel in bulk for comparison to the measurement near the surface. This is particularly important for measurements in living systems where an electrode response may change over time. Finite element method (FEM) modeling places the technique on a quantitative footing to allow the response of the carbon electrode and local delivery rates to be quantified. The technique is extremely versatile, with the local delivery of molecules highly tunable via control of the SICM bias to promote or restrict migration from the pipet orifice. It is expected to have a myriad of applications from drug delivery to screening catalysts.

Fast Nanoscale Surface Charge Mapping with Pulsed-Potential Scanning Ion Conductance Microscopy.

A vast range of interfacial systems exhibit charge heterogeneities on the nanoscale. These differences in local surface charge density are challenging to visualize, but recent work has shown the scanning ion conductance microscope (SICM) to be a very promising tool to spatially resolve and map surface charge and topography via a hopping potential sweep technique with a single nanopipette probe, with harmonic modulation of a bias applied between quasi-reference counter electrodes in the nanopipette and bulk solution, coupled with lock-in detection. Although powerful, this is a relatively slow process, with limitations on resolution and the size of the images that can be collected. Herein, we demonstrate a new scanning routine for mapping surface charge and topography with SICM, which increases the data acquisition rate by an order of magnitude and with the potential for further gains. Furthermore, the method is simplified, eliminating the need for bias modulation lock-in detection, by utilizing a potential-pulse, chronoamperometric approach, with self-referencing calibration of the response at each pixel in the image. We demonstrate the application of this new method to both a model substrate and living PC-12 cells under physiological (high ionic strength) conditions, where charge mapping is most challenging (small Debye length). This work contributes significantly to the emergence of SICM as a multifunctional technique for simultaneously probing interfacial structure and function with nanometer resolution.

Write-Read 3D Patterning with a Dual-Channel Nanopipette.

Nanopipettes are becoming extremely versatile and powerful tools in nanoscience for a wide variety of applications from imaging to nanoscale sensing. Herein, the capabilities of nanopipettes to build complex free-standing three-dimensional (3D) nanostructures are demonstrated using a simple double-barrel nanopipette device. Electrochemical control of ionic fluxes enables highly localized delivery of precursor species from one channel and simultaneous (dynamic and responsive) ion conductance probe-to-substrate distance feedback with the other for reliable high-quality patterning. Nanopipettes with 30-50 nm tip opening dimensions of each channel allowed confinement of ionic fluxes for the fabrication of high aspect ratio copper pillar, zigzag, and Γ-like structures, as well as permitted the subsequent topographical mapping of the patterned features with the same nanopipette probe as used for nanostructure engineering. This approach offers versatility and robustness for high-resolution 3D "printing" (writing) and read-out at the nanoscale.

Frontiers in Nanoscale Electrochemical Imaging: Faster, Multifunctional, and Ultrasensitive.

A wide range of interfacial physicochemical processes, from electrochemistry to the functioning of living cells, involve spatially localized chemical fluxes that are associated with specific features of the interface. Scanning electrochemical probe microscopes (SEPMs) represent a powerful means of visualizing interfacial fluxes, and this Feature Article highlights recent developments that have radically advanced the speed, spatial resolution, functionality, and sensitivity of SEPMs. A major trend has been a coming together of SEPMs that developed independently and the use of established SEPMs in completely new ways, greatly expanding their scope and impact. The focus is on nanopipette-based SEPMs, including scanning ion conductance microscopy (SICM), scanning electrochemical cell microscopy (SECCM), and hybrid techniques thereof, particularly with scanning electrochemical microscopy (SECM). Nanopipette-based probes are made easily, quickly, and cheaply with tunable characteristics. They are reproducible and can be fully characterized. Their response can be modeled in considerable detail so that quantitative maps of chemical fluxes and other properties (e.g., local charge) can be obtained and analyzed. This article provides an overview of the use of these probes for high-speed imaging, to create movies of electrochemical processes in action, to carry out multifunctional mapping such as simultaneous topography-charge and topography-activity, and to create nanoscale electrochemical cells for the detection, trapping, and analysis of single entities, particularly individual molecules and nanoparticles (NPs). These studies provide a platform for the further application and diversification of SEPMs across a wide range of interfacial science.

Surface Charge Visualization at Viable Living Cells.

Scanning ion conductance microscopy (SICM) is demonstrated to be a powerful technique for quantitative nanoscale surface charge mapping of living cells. Utilizing a bias modulated (BM) scheme, in which the potential between a quasi-reference counter electrode (QRCE) in an electrolyte-filled nanopipette and a QRCE in bulk solution is modulated, it is shown that both the cell topography and the surface charge present at cellular interfaces can be measured simultaneously at high spatial resolution with dynamic potential measurements. Surface charge is elucidated by probing the properties of the diffuse double layer (DDL) at the cellular interface, and the technique is sensitive at both low-ionic strength and under typical physiological (high-ionic strength) conditions. The combination of experiments that incorporate pixel-level self-referencing (calibration) with a robust theoretical model allows for the analysis of local surface charge variations across cellular interfaces, as demonstrated on two important living systems. First, charge mapping at Zea mays root hairs shows that there is a high negative surface charge at the tip of the cell. Second, it is shown that there are distinct surface charge distributions across the surface of human adipocyte cells, whose role is the storage and regulation of lipids in mammalian systems. These are new features, not previously recognized, and their implications for the functioning of these cells are highlighted.

AuD-degree holders in tenure-track positions: survey of program chairpersons and AuD-degree holders.

BACKGROUND: The doctor of audiology (AuD) degree is now the entry-level degree for the profession of audiology. Typically, AuD programs train professionals for clinical careers, while those offering PhDs educate students for university teaching and research positions. Some in the communication sciences and disorders have predicted that there could be a shortage of PhDs in academic institutions over the next decade as senior faculty members with PhDs retire, AuD programs expand, and likely fewer students complete PhD degrees or elect to pursue careers in academia. If a PhD shortage becomes a reality, then one solution might be to include AuDs as candidates for vacant academic tenure-track positions. PURPOSE: To survey AuD-degree holders' (AuDs') and program chairpersons' (chairs') views about AuDs in academic tenure-track positions. RESEARCH DESIGN: National Internet survey Data Collection and Analysis: Two questionnaires were designed for this study. One was e-mailed to 1575 "AuDs in general" (randomly sampled from the American Academy of Audiology Membership Directory) and 132 "AuDs in academia." The other was e-mailed to 64 chairs from programs offering the AuD. The two surveys included similar questions so that comparisons could be made across groups. Potential respondents were e-mailed an informational letter inviting them to participate by completing a survey on SurveyMonkey within a 2 wk period in March and April 2010. This process resulted in three data sets: (1) AuDs in general, (2) AuDs in academia, and (3) program chairs. RESULTS: Return rates were 25, 26, and 45% for the three sampling methods for recruiting AuDs in general, AuDs in academia, and program chairs, respectively. Of the respondents, few AuDs held academic tenure-track positions or had achieved rank and tenure success in them. Those AuDs in academia usually had to meet the same or similarly rigorous criteria (with heavier emphasis on teaching than on research) for advancement as did PhD faculty. Overall, AuDs tended to believe that AuDs could be appointed to and succeed at tenure-track positions; chairs reported that such appointments were not permitted in most programs, did not personally believe that AuDs should hold these positions, and felt that AuDs would have more difficulty than PhDs in achieving success in them. Obstacles to AuDs' success in tenure-track positions reported by all three groups included lack of research skills and mentors, biases from faculty within and outside of audiology departments, and poorer pay than could be earned in the private sector. CONCLUSIONS: Considerable variability existed in the types of and titles for faculty positions held by AuDs in academia. Few AuDs were employed in tenure-track positions. Contrary to many of the chairs' responses, most AuDs felt they would be successful in such positions. Many of the AuDs suggested that universities with AuD programs should add more research and mentorship opportunities and tenure tracks for clinicians. Most respondents believed there is a need for both AuDs and PhDs in academic programs. These findings should be of interest to AuDs, chairs, and other stakeholders in academia, and the survey responses identified some areas warranting future investigation.

Being global in public health practice and research: complementary competencies are needed.

Different sets of competencies in public health, global health and research have recently emerged, including the Core Competencies for Public Health in Canada (CCPHC). Within this context, we believe it is important to articulate competencies for globalhealth practitioners-educators and researchers that are in addition to those outlined in the CCPHC. In global health, we require knowledge and skills regarding: north-south power dynamics, linkages between local and global health problems, and the roles of international organizations. We must be able to work responsibly in low-resource settings, foster self-determination in a world rife with power differentials, and engage in dialogue with stakeholders globally. Skills in cross-cultural communication and the ability to critically self-reflect on one's own social location within the global context are essential. Those in global health must be committed to improving health equity through global systems changes and be willing to be mentored and to mentor others across borders. We call for dialogue on these competencies and for development of ways to assess both their demonstration in academic settings and their performance in global health practice and research.