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1.
Nat Commun ; 7: 11584, 2016 06 14.
Article in English | MEDLINE | ID: mdl-27296550

ABSTRACT

The core of a ferromagnetic vortex domain creates a strong, localized magnetic field, which can be manipulated on nanosecond timescales, providing a platform for addressing and controlling individual nitrogen-vacancy centre spins in diamond at room temperature, with nanometre-scale resolution. Here, we show that the ferromagnetic vortex can be driven into proximity with a nitrogen-vacancy defect using small applied magnetic fields, inducing significant nitrogen-vacancy spin splitting. We also find that the magnetic field gradient produced by the vortex is sufficient to address spins separated by nanometre-length scales. By applying a microwave-frequency magnetic field, we drive both the vortex and the nitrogen-vacancy spins, resulting in enhanced coherent rotation of the spin state. Finally, we demonstrate that by driving the vortex on fast timescales, sequential addressing and coherent manipulation of spins is possible on ∼100 ns timescales.

2.
J Phys Condens Matter ; 28(16): 165602, 2016 Apr 27.
Article in English | MEDLINE | ID: mdl-27001951

ABSTRACT

We studied the magneto-optical response of a canonical topological insulator Bi2Se3 with the goal of addressing a controversial issue of electron-phonon coupling. Magnetic-field induced modifications of reflectance are very pronounced in the infrared part of the spectrum, indicating strong electron-phonon coupling. This coupling causes an asymmetric line-shape of the 60 cm(-1) phonon mode, and is analyzed within the Fano formalism. The analysis reveals that the Fano asymmetry parameter (q) changes sign when the cyclotron resonance is degenerate with the phonon mode. To the best of our knowledge this is the first example of magnetic field driven q-reversal.

3.
Ann Oncol ; 27(4): 575-90, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26646754

ABSTRACT

BACKGROUND: Preventive therapy is a risk reduction option for women who have an increased risk of breast cancer. The effectiveness of preventive therapy to reduce breast cancer incidence depends on adequate levels of uptake and adherence to therapy. We aimed to systematically review articles reporting uptake and adherence to therapeutic agents to prevent breast cancer among women at increased risk, and identify the psychological, clinical and demographic factors affecting these outcomes. DESIGN: Searches were carried out in PubMed, CINAHL, EMBASE and PsychInfo, yielding 3851 unique articles. Title, abstract and full text screening left 53 articles, and a further 4 studies were identified from reference lists, giving a total of 57. This review was prospectively registered with PROSPERO (CRD42014014957). RESULTS: Twenty-four articles reporting 26 studies of uptake in 21 423 women were included in a meta-analysis. The pooled uptake estimate was 16.3% [95% confidence interval (CI) 13.6-19.0], with high heterogeneity (I(2) = 98.9%, P < 0.001). Uptake was unaffected by study location or agent, but was significantly higher in trials [25.2% (95% CI 18.3-32.2)] than in non-trial settings [8.7% (95% CI 6.8-10.9)] (P < 0.001). Factors associated with higher uptake included having an abnormal biopsy, a physician recommendation, higher objective risk, fewer side-effect or trial concerns, and older age. Adherence (day-to-day use or persistence) over the first year was adequate. However, only one study reported a persistence of ≥ 80% by 5 years. Factors associated with lower adherence included allocation to tamoxifen (versus placebo or raloxifene), depression, smoking and older age. Risk of breast cancer was discussed in all qualitative studies. CONCLUSION: Uptake of therapeutic agents for the prevention of breast cancer is low, and long-term persistence is often insufficient for women to experience the full preventive effect. Uptake is higher in trials, suggesting further work should focus on implementing preventive therapy within routine care.


Subject(s)
Breast Neoplasms/drug therapy , Breast Neoplasms/prevention & control , Chemoprevention/methods , Breast Neoplasms/epidemiology , Chemoprevention/adverse effects , Female , Humans , Raloxifene Hydrochloride/adverse effects , Raloxifene Hydrochloride/therapeutic use , Tamoxifen/adverse effects , Tamoxifen/therapeutic use
4.
J Phys Condens Matter ; 25(7): 075501, 2013 Feb 20.
Article in English | MEDLINE | ID: mdl-23328626

ABSTRACT

We present the results of an infrared spectroscopy study of topological insulators Bi(2)Se(3), Bi(2)Te(3) and Sb(2)Te(3). Reflectance spectra of all three materials look similar, with a well defined plasma edge. However, there are some important differences. Most notably, as temperature decreases the plasma edge shifts to lower frequencies in Bi(2)Se(3), whereas in Bi(2)Te(3) and Sb(2)Te(3) it shifts to higher frequencies. In the loss function spectra we identify asymmetric broadening of the plasmon, and assign it to the presence of charge inhomogeneities. It remains to be seen if charge inhomogeneities are characteristic of all topological insulators, and whether they are of intrinsic or extrinsic nature.


Subject(s)
Antimony/chemistry , Bismuth/chemistry , Selenium/chemistry , Spectrophotometry, Infrared , Tellurium/chemistry , Electric Conductivity , Static Electricity
5.
Eur J Clin Pharmacol ; 68(5): 777-82, 2012 May.
Article in English | MEDLINE | ID: mdl-22127619

ABSTRACT

OBJECTIVE: To assess the efficacy of patient-centered label (PCL) instructions on the knowledge and comprehension of prescription drug use compared to standard instructions. METHODS: A total of 94 participants recruited from an outpatient clinic in Ireland were each randomly assigned to receive: (1) standard prescription instructions written as times per day (usual care), (2) PCL instructions that specify explicit timing with standard intervals (morning, noon, evening, bedtime) or with mealtime anchors (both PCL), or (3) PCL instructions with a graphic aid to visually depict dose and timing of the medication (PCL + Graphic). The outcome was correct interpretation of the instructions. RESULTS: PCL instructions were more likely to be correctly interpreted than the standard instructions [adjusted relative risk (RR) 1.08, 95% confidence interval (CI) 0.98-1.18]. The inclusion of the graphic aid (PCL + Graphic) decreased the rates of correct interpretation compared to PCL instructions alone (RR 0.98, 95% CI 0.91-1.05). There was a significant interaction between instruction type and health literacy (p = 0.01). Those with limited health literacy were more likely to correctly interpret the PCL labels (91%) than the standard labels (66%), and those with adequate health literacy performed equally well. CONCLUSION: The PCL approach may improve patients' understanding and use of their medication regimen.


Subject(s)
Drug Labeling , Patient Education as Topic/methods , Precision Medicine , Prescription Drugs/administration & dosage , Adult , Age Factors , Cross-Sectional Studies , Drug Administration Schedule , Female , Health Literacy , Hospitals, Teaching , Humans , Ireland , Male , Medication Adherence , Outpatient Clinics, Hospital , Urban Health
6.
AIDS Care ; 17(7): 863-73, 2005 Oct.
Article in English | MEDLINE | ID: mdl-16120503

ABSTRACT

Successful management of HIV requires patient understanding and ability to act on treatment information. We examined the relationship between patient literacy and understanding of HIV treatment. Literacy, knowledge of CD4 count and viral load, and correct identification of HIV medications in regimen were evaluated in 204 patients receiving care in Shreveport, Louisiana and Chicago, Illinois. One-third of patients had limited literacy skills. These patients were less able to describe CD4 count (p < 0.001), viral load (p < 0.001) and to correctly identify medications in their regimen (p < 0.001). In the multivariate analysis, limited literacy was an independent predictor of poor understanding of CD4 count (OR 2.9, 95% CI: 1.3-6.3) and viral load (OR 4.1, 95% CI: 1.9-8.8). For correct medication identification, a significant interaction was found between number of HIV medications and literacy level. Among patients taking only 1-2 HIV medications, 100% of higher literate patients were able to identify their medications, compared to none of the lower literate patients prescribed three or more HIV medications. Patients with limited literacy skills may lack essential knowledge related to their HIV treatment. Clinicians may require additional training for improving communication with these patients.


Subject(s)
Antiretroviral Therapy, Highly Active , HIV Infections/drug therapy , Health Knowledge, Attitudes, Practice , Adult , Educational Status , Female , Humans , Male , Physician-Patient Relations , Surveys and Questionnaires , United States
7.
Int J STD AIDS ; 15(11): 747-52, 2004 Nov.
Article in English | MEDLINE | ID: mdl-15537462

ABSTRACT

Pharmaceutical management of HIV infection is complex, and proper adherence to antiretroviral regimens is contingent on active patient involvement in treatment. We examined the relationship between patient understanding of HIV and its treatment and health literacy. Structured interviews were conducted with 157 HIV-infected individuals receiving care at a community-based clinic in Shreveport, Louisiana, USA. In all, 48% of patients were reading below a 9th grade level. One-third of patients could not name their HIV medications and this was significantly related to low literacy (P < 0.01). Two-thirds of those reading below the 9th grade level did not know how to take their medications correctly (P < 0.05), and 75% did not know the meaning of a CD4 count or viral load (P < 0.001). Patients with low literacy skills were more likely to state that their physician was their sole source of HIV information (P < 0.005). Physicians may require training to appropriately convey health information to patients of low literacy.


Subject(s)
HIV Infections/therapy , Health Education/statistics & numerical data , Health Knowledge, Attitudes, Practice , Patient Education as Topic , Adult , Decision Making , Female , HIV Infections/prevention & control , HIV Infections/transmission , Humans , Male , Physician-Patient Relations , United States
8.
J Behav Ther Exp Psychiatry ; 32(1): 1-16, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11729942

ABSTRACT

The present report replicates and extends previous work examining response patterns to repeated presentation of CO2. In previous studies, two distinct response patterns to repeated presentation of 35% CO2 were noted, representing habituation and nonhabituation of anxiety. In this report, 21 participants who had never experienced a panic attack but who reported high levels of anxiety sensitivity were presented with 12 trials of 20% CO2, followed by a trial involving inhalation of room air (to examine dishabituation) and two more trials of 20% CO2. Results indicated that 67% of the sample reported habituation of anxiety. Reductions in anxiety across inhalations were paralleled by changes in tidal volume, perceived panic symptom severity, and feelings of panic. Notable dishabituation was observed in the nonhabituation sample. Results are discussed in the light of basic learning processes underlying the treatment of Panic Disorder (PD).


Subject(s)
Anxiety/diagnosis , Anxiety/metabolism , Carbon Dioxide/analysis , Adult , Fear , Female , Habituation, Psychophysiologic , Humans , Inhalation , Male , Severity of Illness Index , Surveys and Questionnaires
10.
J Contin Educ Nurs ; 27(6): 245-52, 1996.
Article in English | MEDLINE | ID: mdl-9025414

ABSTRACT

This study measured changes in knowledge acquisition and application of the Hersey and Blanchard model of leadership styles and leadership style adaptability among 144 registered nurses who participated in a four-day management institute. A pre- and post-institute administration of the LEAD-Self instrument was conducted. Although the findings demonstrated a significant change in the participants' leadership styles, the data revealed that outcomes were not as positive as had been assumed based on participants' self-reports. The discussion of findings reveals the complexity and the necessity of measuring learning outcomes for continuing education program improvement.


Subject(s)
Education, Nursing, Continuing/standards , Leadership , Nurse Administrators/education , Nursing, Supervisory/organization & administration , Educational Measurement , Humans , Models, Nursing , Organizational Innovation , Program Evaluation
12.
Semin Oncol Nurs ; 5(2): 77-81, 1989 May.
Article in English | MEDLINE | ID: mdl-2727445

ABSTRACT

Even though nurses engage in ethical decision-making on a daily basis, few practical resources are available and little is known about how nurses resolve ethical dilemmas in the clinical setting. A descriptive clinical ethical decision-making model has been presented and factors influencing current ethical decision-making skills have been identified. What is known suggests that some nurses do not consider multiple options during ethical deliberations. This may be due to the fact that there is limited time available for ethical deliberations in the clinical setting. In addition, the nurse may be prevented from implementing the chosen option by a variety of yet unidentified and uncontrolled variables. Recommendations In order to increase the amount of time available for ethical deliberation, a pro-active approach must be developed toward ethical issues. Ethics rounds need to be integrated into traditional medical and nursing rounds as a means for identifying ethical issues. Research is needed to describe (1) the process nurses use to resolve ethical situations, (2) the variables influencing decision-making in the clinical setting, and (3) the problems nurses experience during ethical decision-making. The nurse's ability to identify several options may increase as more time is available for ethical decision-making. Traditionally, nurses have identified ethical dilemmas that imply two options. Nurses need to consider ethical issues, concerns, and situations in order to identify multiple options. Ethics discussions, inservice education, and consultations with ethicists would provide the opportunity to critique previously experienced ethical situations and enhance the nurses's decision-making skills for future situations.


Subject(s)
Decision Making , Ethics, Nursing , Models, Theoretical , Decision Trees , Humans
15.
J Pharm Sci ; 69(1): 92-3, 1980 Jan.
Article in English | MEDLINE | ID: mdl-7354454

ABSTRACT

A simultaneous assay for the detection of clofibrate and its metabolite, clofibric acid [2-(p-chlorophenoxy)-2-methylpropionic acid], is described. This GLC method is rapid and does not require a derivatization step. It is sensitive to 1-microgram/ml levels of either compound in biological samples and can be used to characterize the in vivo conversion of clofibrate ester to the free acid.


Subject(s)
Clofibrate/analogs & derivatives , Clofibrate/blood , Clofibric Acid/blood , Chromatography, Gas , Humans , Hydrolysis
16.
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