Cellular mechanisms underlying carry-over effects after magnetic stimulation.

Magnetic fields are widely used for neuromodulation in clinical settings. The intended effect of magnetic stimulation is that neural activity resumes its pre-stimulation state right after stimulation. Many theoretical and experimental works have focused on the cellular and molecular basis of the acute neural response to magnetic field. However, effects of magnetic stimulation can still last after the termination of the magnetic stimulation (named "carry-over effects"), which could generate profound effects to the outcome of the stimulation. However, the cellular and molecular mechanisms of carry-over effects are largely unknown, which renders the neural modulation practice using magnetic stimulation unpredictable. Here, we investigated carry-over effects at the cellular level, using the combination of micro-magnetic stimulation (µMS), electrophysiology, and computation modeling. We found that high frequency magnetic stimulation could lead to immediate neural inhibition in ganglion neurons from Aplysia californica, as well as persistent, carry-over inhibition after withdrawing the magnetic stimulus. Carry-over effects were found in the neurons that fired action potentials under a variety of conditions. The carry-over effects were also observed in the neurons when the magnetic field was applied across the ganglion sheath. The state of the neuron, specifically synaptic input and membrane potential fluctuation, plays a significant role in generating the carry-over effects after magnetic stimulation. To elucidate the cellular mechanisms of such carry-over effects under magnetic stimulation, we simulated a single neuron under magnetic stimulation with multi-compartment modeling. The model successfully replicated the carry-over effects in the neuron, and revealed that the carry-over effect was due to the dysfunction of the ion channel dynamics that were responsible for the initiation and sustaining of membrane excitability. A virtual voltage-clamp experiment revealed a compromised Na conductance and enhanced K conductance post magnetic stimulation, rendering the neurons incapable of generating action potentials and, therefore, leading to the carry over effects. Finally, both simulation and experimental results demonstrated that the carry-over effects could be controlled by disturbing the membrane potential during the post-stimulus inhibition period. Delineating the cellular and ion channel mechanisms underlying carry-over effects could provide insights to the clinical outcomes in brain stimulation using TMS and other modalities. This research incentivizes the development of novel neural engineering or pharmacological approaches to better control the carry-over effects for optimized clinical outcomes.

Improving focality and consistency in micromagnetic stimulation.

The novel micromagnetic stimulation (µMS) technology aims to provide high resolution on neuronal targets. However, consistency of neural activation could be compromised by a lack of surgical accuracy, biological variation, and human errors in operation. We have recently modeled the activation of an unmyelinated axon by a circular micro-coil. Although the coil could activate the axon, its performance sometimes lacked focality and consistency. The site of axonal activation could shift by several experimental factors, including the reversal of the coil current, displacement of the coil, and changes in the intensity of the stimulation. Current clinical practice with transcranial magnetic stimulation (TMS) has suggested that figure-eight coils could provide better performance in magnetic stimulation than circular coils. Here, we estimate the performance of µMS by a figure-eight micro-coil, by exploring the impact of the same experimental factors on its focality and consistency in axonal activation. We derived the analytical expression of the electric field and activating function generated by the figure-eight micro-coil, and estimated the location of axonal activation. Using NEURON modeling of an unmyelinated axon, we found two different types (A and B) of axon activation by the figure-eight micro-coil, mediated by coil currents of reversed direction. Type A activation is triggered by membrane hyperpolarization followed by depolarization; Type B activation is triggered by direct membrane depolarization. Consequently, the two types of stimulation are governed by distinct ion channel mechanisms. In comparison to the circular micro-coil, the figure-eight micro-coil requires significantly less current for axonal activation. Under figure-eight micro-coil stimulation, the site of axonal activation does not change with the reversal of the coil current, displacement of the coil, or changes in the intensity of the stimulation. Ultimately, the figure-eight micro-coil provides a more efficient and consistent site of activation than the circular micro-coil in µMS.

Systematic Review of Burnout in US Nurses.

Nurses experience high levels of burnout, and this has become a major factor in recruitment and retention of nurses. Several factors have been associated with burnout, but it is not clear which factors are the most significant predictors. Understanding the most prevalent factors that are associated with burnout will allow for the development and implementation of interventions to ameliorate and/or reduce burnout in the nursing workforce.

The Influence of Leadership Style and Nurse Empowerment on Burnout.

The levels of burnout nurses experience continue to increase with resultant negative impacts on the nursing work environment, patient outcomes, and the retention of qualified nurses. Nurse leaders are essential in developing and fostering positive work environments that retain an empowered and motivated workforce. Research indicates that positive and relational leadership styles can improve nurses' job satisfaction, organizational commitment, and retention while concurrently reducing emotional exhaustion and burnout.

Heart failure self-management and normalizing symptoms: an exploration of decision making in the community.

OBJECTIVE: To explore the decision making processes undertaken by community-dwelling individuals with heart failure as they experience symptom changes. BACKGROUND: Heart failure patients are responsible for daily self-management that includes responding to symptom fluctuations between exacerbations. Despite education, some patients fail to seek timely medical intervention when symptoms change. METHODS: Semi-structured interviews were conducted with homecare patients after receiving self-management education. Grounded theory methods and qualitative software were used to collect and analyze the data. RESULTS: Five themes were identified: perceiving symptoms, alleviating actions and control, normalizing symptoms, absence of help seeking behaviors, and decreased functional capacity. Normalizing symptoms included actions taken by participants to mitigate symptom fluctuations. Daily fluctuations were assimilated into normal life resulting in desensitization of symptom recognition and decreased functional capacity. CONCLUSIONS: Findings support the need to educate on early symptom recognition, the benefits of safe physical activity, and building a system to support self-management patient-physician collaboration.

Common Gastrointestinal Complications Associated with Human Immunodeficiency Virus/AIDS: An Overview.

Highly active antiretroviral therapy (HAART) has transformed human immunodeficiency virus (HIV)/AIDS into a manageable chronic illness. People living with HIV/AIDS (PLWHA) can experience multiple physical symptoms or problems related to HIV infection and treatment. A common problem for PLWHA continues to be diarrhea and nausea and vomiting (NV). Diarrhea and NV can negatively impact the quality of life and adherence to medication therapy among PLWHA and are common reasons to change or discontinue HAART regimens. Because diarrhea and NV can have substantial negative health outcomes for PLWHA, it is important to understand the causes of these conditions.

Protein secondary structure prediction from circular dichroism spectra using a self-organizing map with concentration correction.

Collecting circular dichroism (CD) spectra for protein solutions is a simple experiment, yet reliable extraction of secondary structure content is dependent on knowledge of the concentration of the protein--which is not always available with accuracy. We previously developed a self-organizing map (SOM), called Secondary Structure Neural Network (SSNN), to cluster a database of CD spectra and use that map to assign the secondary structure content of new proteins from CD spectra. The performance of SSNN is at least as good as other available protein CD structure-fitting algorithms. In this work we apply SSNN to a collection of spectra of experimental samples where there was suspicion that the nominal protein concentration was incorrect. We show that by plotting the normalized root mean square deviation of the SSNN predicted spectrum from the experimental one versus a concentration scaling-factor it is possible to improve the estimate of the protein concentration while providing an estimate of the secondary structure. For our implementation (51 data points 240-190 nm in nm increments) good fits and structure estimates were obtained if the NRMSD (normalized root mean square displacement, RMSE/data range) is <0.03; reasonable for NRMSD <0.05; and variable above this. We also augmented the reference database with 100% helical spectra and truly random coil spectra.

Elucidating protein secondary structure with circular dichroism and a neural network.

Circular dichroism spectroscopy is a quick method for determining the average secondary structures of proteins, probing their interactions with their environment, and aiding drug discovery. This article describes the development of a self-organising map structure-fitting methodology named secondary structure neural network (SSNN) to aid this process and reduce the level of expertise required. SSNN uses a database of spectra from proteins with known X-ray structures; prediction of structures for new proteins is then possible. It has been designed as 3 units: SSNN1 takes spectra for known proteins, clusters them into a map, and SSNN2 creates a matching structure map. SSNN3 places unknown spectra on the map and gives them structure vectors. SSNN3 output illustrates the process and results obtained. We detail the strengths and weaknesses of SSNN and compare it with widely accepted structure fitting programs. Current input format is Δε per amino acid residue from 240 to 190 nm in 1 nm steps for the known and unknown proteins and a vector summarizing the secondary structure elements of the known proteins. The format is readily modified to include input data with, for example, extended wavelength ranges or different assignment of secondary structures. SSNN can be used either pretrained with a reference set from the CDPro web site (direct application of SSNN3, with the provided output from SSNN1 and SSNN2) or all three modules can be used as required. SSNN3 is available trained (with the reference set of the 48-spectra set used in this work complemented by five additional spectra) at http://www2.warwick.ac.uk/fac/sci/chemistry/research/arodger/arodgergroup/research_intro/instrumentation/ssnn/.

Regionally increasing baccalaureate-prepared nurses: development of the RIBN model.

The nursing shortage remains an acute problem at the national level and significantly endangers the provision of safe and effective health care. One of the most significant problems fueling the nursing shortage in the United States is the lack of faculty to educate the number of qualified individuals applying to nursing programs. A major factor driving the shortage of faculty emanates from the current trend in basic nursing education that is increasing the proportion of nurses with an associate degree in nursing (ADN) as their terminal professional education. Community colleges, that offer the associate degree, play a crucial role in providing access to nursing education. However, they now account for more than 2/3 of all new nursing graduates in the United States. With over 2/3 of our new nurses completing only associate degree programs, the faculty pipeline continues to decrease. This also means fewer bachelor of science in nursing (BSN) and higher-degree-prepared nurses available for advanced clinical practice, management roles, and public health services. It is therefore critical to identify and implement new pathways to increase the number of ADN graduates who complete baccalaureate education and, thereby, increase the percentage of BSN-prepared nurses. This article describes the development and implementation of a model in North Carolina to regionally increase the number of baccalaureate-prepared nurses through the development of partnerships between community colleges and universities.

Regionally increasing baccalaureate-prepared nurses in North Carolina: the RIBN Project.

A more highly educated nursing workforce is needed to address the increasingly complex health care needs of our citizens and to expand the pool for future faculty and advanced practice nurses. North Carolina must create new partnerships between community colleges and universities to support seamless progression toward a baccalaureate degree. The RIBN model provides one option to meet this goal.

Women's initial experience of abnormal papanicolaou smear.

To discover the early subjective experience of women affected by abnormal Papanicolaou smear, a qualitative study was undertaken with 8 North Carolina women, 4 to 12 months postnotification of their first abnormal result. Data were analyzed via grounded theory methodology to identify a core theory that could guide interventions to improve follow-up for cancer prevention. This theoretical process is described as a labyrinth journey-an imperative healing process undertaken by all participants, who undertook the following tasks: evaluating peril, seeking refuge, obtaining information, and reframing their self-image. Women who also learned they were infected with the human papillomavirus faced a prolonged sense of threat to their sense of sexual well-being. Their additional tasks related to reevaluating their sexual self-image, and they continued to work on these reframing tasks throughout their 1st year's journey. Progress through the labyrinth depended upon emotional or spiritual support, nonjudgmental acceptance and access to accurate information.

While unison is at it, why not outlaw the tories as well?

I read with interest your piece about Unison's campaign to outlaw nurse's rights to belong to the BNP (news April 29) I suggest they go one step further and implement a ban on Conservative party members.

Promoting collaboration in nursing education: the development of a regional simulation laboratory.

This article describes a collaboratively developed plan for a regional patient simulation laboratory for nursing education. The Western North Carolina Regional Simulation Laboratory will be located at the Enka Campus of the Asheville-Buncombe Technical Community College at the Department of Nursing of Western Carolina University (Candler, NC). A proactive collaborative consortium has been established to help meet the demand for nursing education in the 13 most rural mountain counties of western North Carolina. Through a 2-year process with regional networking, the nursing administration of Western Carolina University, Mission Hospitals, Asheville-Buncombe Technical Community College, and affiliated community colleges, consortium hospitals, and emergency care services developed a vision and a proposal for an innovative program for the nursing education of the future. The consortium proposed the establishment of a 3-year integrated educational program utilizing state-of-the-art simulation manikin technology. Financial resources were obtained from a charitable grant from The Duke Endowment (Charlotte, NC). Sustainability of funding will be ensured through university, hospital, and community college collaboration.

Bearing witness to suffering in AIDS: the testing of a substantive theory.

AIDS volunteerism, as a response by those affected by loss associated with HIV/AIDS, has been described as an act of bearing witness. The theory "bearing witness to suffering in HIV/AIDS," proposes that AIDS volunteerism assists individuals affected by loss to increase their levels of hope, self-esteem, social support, and develop a sense of purpose in life (PIL). The purpose of this descriptive research was to determine if AIDS volunteerism, hope, self-esteem, and social support were predictive of PIL among individuals affected by loss from HIV/AIDS. Path analysis was used to analyze data. Hope, social support, and self-esteem were found to have significant positive effects on PIL and accounted for 66% of the total variance. The results from this study will be used to further develop the theory of bearing witness; this theory may be useful to develop and test interventions to relieve the suffering experienced by individuals affected by HIV/AIDS.