Top ten risk factors for morbidity and mortality in patients with chronic systolic heart failure and elevated heart rate: the SHIFT risk model

Aims We identified easily obtained baseline characteristics associated with outcomes in patients with chronic heart failure (HF) and elevated heart rate (HR) receiving contemporary guideline-recommended therapy in the SHIFT trial, and used them to develop a prognostic model. Methods We selected the 10 best predictors for each of four outcomes (cardiovascular death or HF hospitalisation; all-cause mortality; cardiovascular mortality; and HF hospitalisation). All variables with p &#60; 0.05 for association were entered into a forward stepwise Cox regression model. Our initial analysis excluded baseline therapies, though randomisation to ivabradine or placebo was forced into the model for the composite endpoint and HF hospitalisation. Results Increased resting HR, low ejection fraction, raised creatinine, New York Heart Association class III/IV, longer duration of HF, history of left bundle branch block, low systolic blood pressure and, for three models, age were strong predictors of all outcomes. Additional predictors were low body mass index, male gender, ischaemic HF, low total cholesterol, no history of hyperlipidaemia or dyslipidaemia and presence of atrial fibrillation/flutter. The c-statistics for the four outcomes ranged from 67.6% to 69.5%. There was no evidence for lack of fit of the models with the exception of all-cause mortality (p = 0.017). Similar results were found including baseline therapies. Conclusion The SHIFT Risk Model includes simple, readily obtainable clinical characteristics to produce important prognostic information in patients with chronic HF, systolic dysfunction, and elevated HR. This may help better calibrate management to individual patient risk.</p

Effect of visit-to-visit variation of heart rate and systolic blood pressure on outcomes in chronic systolic heart failure: results from the Systolic Heart Failure Treatment With the If Inhibitor Ivabradine Trial (SHIFT) trial

Background: Elevated resting heart rate (HR) and low systolic blood pressure (SBP) are related to poor outcomes in heart failure (HF). The association between visit-to-visit variation in SBP and HR and risk in HF is unknown. Methods and Results: In Systolic Heart Failure Treatment with the If inhibitor ivabradine Trial (SHIFT) patients, we evaluated relationships between mean HR, mean SBP, and visit-to-visit variations (coefficient of variation [CV]=SD/mean×100%) in SBP and HR (SBP-CV and HR-CV, respectively) and primary composite endpoint (cardiovascular mortality or HF hospitalization), its components, all-cause mortality, and all-cause hospitalization. High HR and low SBP were closely associated with risk for primary endpoint, all-cause mortality, and HF hospitalization. The highest number of primary endpoint events occurred in the highest HR tertile (38.8% vs 16.4% lowest tertile; P&lt;0.001). For HR-CV, patients at highest risk were those in the lowest tertile. Patients in the lowest thirds of mean SBP and SBP-CV had the highest risk. The combination of high HR and low HR-CV had an additive deleterious effect on risk, as did that of low SBP and low SBP-CV. Ivabradine reduced mean HR and increased HR-CV, and increased SBP and SBP-CV slightly. Conclusions: Beyond high HR and low SBP, low HR-CV and low SBP-CV are predictors of cardiovascular outcomes with additive effects on risk in HF, but with an unknown effect size. Beyond HR reduction, ivabradine increases HR-CV. Low visit-to-visit variation of HR and SBP might signal risk of cardiovascular outcomes in systolic HF. Clinical Trial Registration: URL: http://www.isrctn.com/. Unique identifier: ISRCTN70429960

Phonon Linewidths and Electron Phonon Coupling in Nanotubes

We prove that Electron-phonon coupling (EPC) is the major source of broadening for the Raman G and G- peaks in graphite and metallic nanotubes. This allows us to directly measure the optical-phonon EPCs from the G and G- linewidths. The experimental EPCs compare extremely well with those from density functional theory. We show that the EPC explains the difference in the Raman spectra of metallic and semiconducting nanotubes and their dependence on tube diameter. We dismiss the common assignment of the G- peak in metallic nanotubes to a Fano resonance between phonons and plasmons. We assign the G+ and G- peaks to TO (tangential) and LO (axial) modes.Comment: 5 pages, 4 figures (correction in label of fig 3

Metacognitive awareness for IL learning and growth: The development and validation of the Information Literacy Reflection Tool (ILRT)

This article describes the development and validation of the Information Literacy Reflection Tool (ILRT), a metacognitive self-assessment for use with undergraduate researchers. It was developed as a teaching and learning tool with the intent to help students recognize and engage the metacognitive domain as a step toward developing personal agency and self-regulation as lifelong, metaliterate learners. Throughout the scale development, three studies were conducted with nine expert reviewers and 44 community college students to consider content and face validity and 542 community college students as part of an item-reduction and construct validation effort. The resulting scale is most appropriately construed through a bifactor model and is made up of 57 items comprising a strong information literacy general factor and six specific factors modestly aligning with each of the threshold concepts outlined in the ACRL Framework for Information Literacy for Higher Education. As a part of the ongoing development of this instrument, work is needed to more fully assess reliability and validity

The Halo Mass Function from Excursion Set Theory. II. The Diffusing Barrier

In excursion set theory the computation of the halo mass function is mapped into a first-passage time process in the presence of a barrier, which in the spherical collapse model is a constant and in the ellipsoidal collapse model is a fixed function of the variance of the smoothed density field. However, N-body simulations show that dark matter halos grow through a mixture of smooth accretion, violent encounters and fragmentations, and modeling halo collapse as spherical, or even as ellipsoidal, is a significant oversimplification. We propose that some of the physical complications inherent to a realistic description of halo formation can be included in the excursion set theory framework, at least at an effective level, by taking into account that the critical value for collapse is not a fixed constant $\delta_c$, as in the spherical collapse model, nor a fixed function of the variance $\sigma$ of the smoothed density field, as in the ellipsoidal collapse model, but rather is itself a stochastic variable, whose scatter reflects a number of complicated aspects of the underlying dynamics. Solving the first-passage time problem in the presence of a diffusing barrier we find that the exponential factor in the Press-Schechter mass function changes from $\exp\{-\delta_c^2/2\sigma^2\}$ to $\exp\{-a\delta_c^2/2\sigma^2\}$, where $a=1/(1+D_B)$ and $D_B$ is the diffusion coefficient of the barrier. The numerical value of $D_B$, and therefore the corresponding value of $a$, depends among other things on the algorithm used for identifying halos. We discuss the physical origin of the stochasticity of the barrier and we compare with the mass function found in N-body simulations, for the same halo definition.[Abridged]Comment: 7 pages, 5 figures. v3: significant conceptual improvements. More detailed comparison with N-body simulations. References adde

Occurrence of lactational mastitis and medical management: a prospective cohort study in Glasgow

This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Background Lactational mastitis is a painful, debilitating condition that if inappropriately managed, may lead women to discontinue breastfeeding prematurely. The aim of this paper is to report the incidence of mastitis in the first six months postpartum in a Scottish population, its impact on breastfeeding duration and to describe the type and appropriateness of the support and management received by affected women from health professionals. Methods A longitudinal study of 420 breastfeeding women was undertaken in Glasgow in 2004/05. Participants were recruited and completed a baseline questionnaire before discharge from hospital. Cases of mastitis were reported either directly to the researchers or were detected during regular follow-up telephone interviews at weeks 3, 8, 18 and 26. Women experiencing mastitis provided further information of their symptoms and the management and advice they received from health professionals. Results In total, 74 women (18%) experienced at least one episode of mastitis. More than one half of initial episodes (53%) occurred within the first four weeks postpartum. One in ten women (6/57) were inappropriately advised to either stop breastfeeding from the affected breast or to discontinue breastfeeding altogether. Conclusion Approximately one in six women is likely to experience one or more episodes of mastitis whilst breastfeeding. A small but clinically important proportion of women continue to receive inappropriate management advice from health professionals which, if followed, could lead them to unnecessarily deprive their infants prematurely of the known nutritional and immunological benefits of breast milk

Reflections Regarding the Social Ecological Model to Address Obesity in Southern California Youth

Childhood overweight and obesity has been a significant public health concern in the United States for decades. School-based obesity prevention programs have been one strategy to address this issue. This article describes the implementation of a knowledge-based, healthy eating intervention delivered to 4th and 5th graders in a southern California school district. Trained graduate students implemented a nutrition education curriculum, consisting of three monthly lessons that would eventually be utilized and sustained by the schools’ Physical Education (PE) teachers in the following school year. As such, the intervention drew upon the Social Ecological Model (SEM) to describe how nutrition education could be implemented in a sustainable way to future generations of youth. Students were assessed on their knowledge and dietary behaviors at pre-test and after the final lesson. Students’ overall nutritional knowledge significantly increased from pre-test to post-test; however their self-reported eating behaviors (e.g., low fruit and vegetable consumption, and high consumption of chips, soda, and sweets) largely remained the same. Although the findings of this study were largely non-significant, we conclude that future interventions, which creatively address different levels of the target population’s environment, may have promise if they are sufficiently dosed